REM >.Src.Invaders REM Taito Space Invaders (Circa 1978) Clone REM (c) DynaByte Software 2008 REM LibASH Extended heap manager (c)2008 DynaByte Software. REM Derived from ASH by Steve Revill (c)2004 7th Software. REM Keys | Title | In-Game REM ======+===============+============= REM SPACE | Start Game | REM S | Screenshot | Screenshot REM Z | | Left. REM X | | Right. REM Enter | | Fire. REM M | Music On/Off | Music On/Off REM + | Volume Up | Volume Up REM - | Volume Down | Volume Down REM P | | Pause/Resume Game. REM Q | Quit Program | Suicide. REM ************************************************************* REM Initialisation Part 1... (Files & Environment.) REM ************************************************************* REM Setup error trapping and announce ourselves... ON ERROR PROCtrap_error:END MODE28:OFF :REM 800*600 (256 Colours) string$="Acorn Invaders. (c)2008 DynaByte Software" PRINT string$:PRINT STRING$(LEN(string$),"-"):PRINT REM Check we have all our essential files... REM Our Hiscore table is a special case as it can be either REM generated if one doesn't exist, or we can carry on regardless REM if we can't create it. REM Set Directory pointers... app_dir$=".Resources." :REM Root resources. gfx_dir$=app_dir$+"Graphics." :REM Graphics. dat_dir$=app_dir$+"Data." :REM Data, Lookups etc. snd_dir$=app_dir$+"Sound." :REM Sound. REM Locate files... (Mission critical...) bail%=FALSE PRINT"Checking files..." IF NOT FNfind(gfx_dir$+"Gfx0","Sprites") THEN bail%=TRUE IF NOT FNfind(gfx_dir$+"Gfx1","Charset") THEN bail%=TRUE IF NOT FNfind(snd_dir$+"Intro","Music") THEN bail%=TRUE IF NOT FNfind(dat_dir$+"Creds","Credits") THEN bail%=TRUE IF NOT FNfind(dat_dir$+"Msg","Messages") THEN bail%=TRUE IF NOT FNfind(dat_dir$+"ImgLUT","Lookups") THEN bail%=TRUE IF NOT FNfind(dat_dir$+"SWIs","Lookups") THEN bail%=TRUE IF bail% THEN ERROR 255,"File Missing!!" PRINT REM Load strings & Lookup Tables... REM We do these here as they share the same code, except they REM setup different global variables... PRINT"Loading Messages..."; :REM Text strings. string_max%=FNstring_enumprocessed(dat_dir$+"Msg","SGSM") DIM string_num%(string_max%),string_msg$(string_max%) PROCstring_load(dat_dir$+"Msg","SGSM",string_num%(),string_msg$()) PRINTFNstring_get(14) PRINTFNstring_get(9)+" "+FNstring_get(3); :REM Sprite names. ilut_max%=FNstring_enumprocessed(dat_dir$+"ImgLUT","TULI") DIM ilut_num%(ilut_max%),ilut_msg$(ilut_max%) PROCstring_load(dat_dir$+"ImgLUT","TULI",ilut_num%(),ilut_msg$()) PRINTFNstring_get(14) PRINTFNstring_get(9)+" "+FNstring_get(13); :REM SWI names. slut_max%=FNstring_enumprocessed(dat_dir$+"SWIs","TULS") DIM slut_num%(slut_max%),slut_msg$(slut_max%) PROCstring_load(dat_dir$+"SWIs","TULS",slut_num%(),slut_msg$()) PRINTFNstring_get(14) REM Setup our variables. (These are used all over...) REM A lot of misc values like timing stores are now held in the REM gamestate% object. Values held here are listed below. Music REM stuff was previously stored in it's own object, but didn't REM really warrant the extra overhead. A lot of the other values REM were bundled into the player% object, but didn't really REM belong there. This new object pulls all this stuff together REM in one place. We also kick the ASH Heap Manager at this point REM and get it going. REM gamestate% object contents... REM Offs.| Usage Offs.| Usage REM -----+-------------------------+-----+----------------------- REM 0 : Sound Status | 32 : HUD Pause game status. REM 4 : Music Handle (TimPlayer)| 36 : HUD Pause game timer. REM 8 : Volume change delay | 40 : Screenshot counter. REM 12 : Last extra life score | 44 : Media writeable flag. REM 16 : Extra life HUD counter | 48 : Not used... REM 20 : Extra life frame toggle | 52 : Number of inv. missiles REM 24 : Extra life frame timer | 56 : Number of bunkers. REM 28 : Pause Game toggle. | 60 : REM -----+-------------------------+-----+----------------------- REM Number of invader missiles (Offset 52)... REM This value represents the maximum number of missiles currently REM allowed on screen. This increases up to a maximum of 10 as the REM player gets further down the line. For ASH allocation and REM freeing purposes, this number is ALWAYS 10 (The size of the REM array.) Slots higher than the number in this offset are masked REM off when it comes to the operation of the handler. REM Timers (Offsets 8, 24 & 36)... REM All timers are snapshots of OS_ReadMonotonicTime used for REM delay or animation events. PRINT:PRINTFNstring_get(12) PRINTFNstring_get(8)+" "+FNstring_get(2) PROCash_init :REM Kick the Heap Manager. gamestate%=FNash_claimfilled(60,0) :REM Claim for state info. gamestate%!0=1:gamestate%!4=-1 gamestate%!40=FNinit_setdumpcounter(0) :REM Screendump counter. IF gamestate%!40=-1 THEN ERROR255,FNstring_get(109) PRINTFNstring_get(15)+STR$(gamestate%!40) bail%=FALSE :REM TRUE to quit game. gamestate%!44=TRUE :REM TRUE to save HiTable. gamestate%!52=5 :REM Invader missiles. gamestate%!56=5 :REM Number of bunkers. cred_size%=0 :REM Credit screen stuff. DIM scores_name$(10),scores_value%(10) :REM HiScore table. DIM scores_rack%(10) REM Objects... Each object (Base, saucer, missile etc.) is REM given a block of memory up to 68 bytes long to hold all REM relevant data for that object. This, apart from being REM quicker, is far easier to code and saves memory (See REM tutorial). These are tokens to address offsets in each REM of those blocks of memory. (See tutorial for how this REM works...) Contents for offsets 32-64 (flags1% - flags9%) will REM be different, depending on the nature of the object. Not all REM objects will have all 9 option flags available. I'll define REM LOCAL variables with more meaningful names and point them to REM these in the object's handler routines. PRINTFNstring_get(8)+" "+FNstring_get(22) REM Object offsets... xpos%=0:ypos%=4:xsize%=8:ysize%=12 :REM Position & Size. dir%=16:speed%=20 :REM Movement. active%=24:beenhit%=28 :REM Object Status. flags1%=32:flags2%=36:flags3%=40 :REM Misc flags. flags4%=44:flags5%=48:flags6%=52 flags7%=56:flags8%=60:flags9%=64 REM Define offsets for screen and rail objects. x_eig%=16:y_eig%=20:setmode%=24 :REM Offsets in screen obj. xfont%=28:yfont%=32 toprail%=16:baserail%=20 :REM Offsets in rail obj. REM Initialise Sound Sub-system and load music... PRINT:PRINTFNstring_get(8)+" "+FNstring_get(1)+" "; ver%=0:SYS FNswi_get(30) TO ver% PRINTFNstring_get(21)+" "+STR$(ver%/100) gamestate%!4=FNtp_loadsong(snd_dir$+"Intro") REM Initialise Graphics Sub-system... REM The variables we're interested in here will be... REM gfx_spriteop% -> The OS Call we'll use to draw graphics. REM gfx_spritepool% -> Block of RAM where our sprites reside. REM gfx_fontpool% -> Block of RAM where our charset resides. REM gfx_area% -> Pointer to our current graphics pool. PRINT:PRINTFNstring_get(17)+" "+FNstring_get(16) SYS FNswi_get(1),, FNswi_get(2) TO gfx_spriteop% PRINTFNstring_get(9)+" "+FNstring_get(4); gfx_spritepool%=FNgfx_load(gfx_dir$+"Gfx0") PRINTFNstring_get(14) PRINTFNstring_get(9)+" "+FNstring_get(5); gfx_fontpool%=FNgfx_load(gfx_dir$+"Gfx1") PRINTFNstring_get(14) gfx_area%=gfx_spritepool% REM Load Credit screen data... REM This was originally as strings in the listing, but REM implementing this in a loop reading data from an array takes REM less space and tidies up the listing somewhat. PRINT:PRINTFNstring_get(9)+" "+FNstring_get(6); hdl%=OPENIN(dat_dir$+"Creds") INPUT#hdl%,magic$ :REM Read magic and verify. IF magic$<>"DERC" THEN CLOSE#hdl%:ERROR 255,FNstring_get(101):END ENDIF INPUT#hdl%,cred_size% :REM Number of lines... DIM cred_str$(cred_size%),cred_spc%(cred_size%) FOR i%=1 TO cred_size% INPUT#hdl%,cred_spc%(i%),cred_str$(i%) NEXT i% CLOSE#hdl% PRINTFNstring_get(14) REM HiScore Table... REM Here, we look for and load, if it exists, our Hiscores file. REM If we can't find one, we check whether we can write to the REM location before we attempt to create one. If we can't REM do that, then we can still run, but the user's scores will REM not be retained on exit. PRINT:PRINTFNstring_get(7) hifile$=dat_dir$+"HiTable" :REM Location of file. IF FNfs_find(hifile$)<>1 THEN IF NOT FNfs_writeable(0,app_dir$) THEN gamestate%!44=FALSE :REM HiTable save flag. PRINTFNstring_get(19)+" "+FNstring_get(10)+" "+FNstring_get(20) ELSE PRINTFNstring_get(19)+" "+FNstring_get(11)+" "+FNstring_get(20) ENDIF PROChitable_create(gamestate%!44) :REM HiTable save flag. ELSE IF NOT FNfs_writeable(1,hifile$) THEN gamestate%!44=FALSE :REM HiTable save flag. PRINTFNstring_get(18)+" "+FNstring_get(10)+" "+FNstring_get(20) ELSE PRINTFNstring_get(18)+" "+FNstring_get(11)+" "+FNstring_get(20) ENDIF PROChitable_load ENDIF PRINT:PRINTFNstring_get(12):PROCwait(150) REM ************************************************************* REM Initialisation Part 2... (Global objects and variables.) REM ************************************************************* REM Reserve memory for global object blocks... screen%=FNash_claim(36):rail%=FNash_claim(24) :REM Global objects. box%=FNash_claim(16) REM Get the video display into a VGA 256 colour mode. This is REM also the same MODE as our sprites. Call to PROCget_screeninfo REM calls the OS to get some values and sets up our screen object REM for us. CLS:PROCget_screeninfo :REM Setup screen object. screen%!xfont%=FNconv_units(8,1) screen%!yfont%=FNconv_units(8,2)+7 REM Define property values for other global objects. rail%!xsize%=FNconv_units(6,1) :REM Rail properties. rail%!ysize%=FNconv_units(6,2) rail%!toprail%=screen%!ysize%-50 rail%!baserail%=30 REM ************************************************************* REM Main Loop... (Title>Game>Title.) REM ************************************************************* REM Start music playing... REM Offs. | Purpose | Value REM ------+---------+------ REM 0 | Status | 0=Mute, 1=Music & SFX, 2=SFX Only. REM 4 | Handle | TimPlayer reference handle. REM 8 | Delay | n=0 - Do it now, n>0 Wait n counts. SYS FNswi_get(33) ,gamestate%!4 :REM Start playing. SYS FNswi_get(36) ,gamestate%!4,128 :REM Set current volume. REM Cycle attract mode and play game... WHILE NOT FNtitle_loop CLS:PROCmain ENDWHILE REM Enclose our goodbyes in a border... REM Setup our border size and position. Centre this on the screen REM and then drop it down by 3px. (Raising the text by 3px would REM break too many things!) Call PROCdraw_box() to produce our REM border and then display our text. Once we've done all that, we REM start to fade our music and bail back to the desktop. CLS:box%!xsize%=220:box%!ysize%=40 box%=FNcentre_sprite_xy(box%,screen%):box%!ypos%-=3 PROCdraw_box(box%):PROCcentre_text_xy(FNstring_get(31),10) IF gamestate%!0=1 THEN SYSFNswi_get(36),gamestate%!4,-1 TO ,cvol% FOR i%=cvol% TO 0 STEP-2 SYSFNswi_get(36),gamestate%!4,i%:PROCwait(4) NEXT i% SYSFNswi_get(35),gamestate%!4 :REM Stop music playing. SYSFNswi_get(32),gamestate%!4 :REM Unload music. gamestate%!4=-1 :REM Clear handle. ENDIF PROCash_destroy :REM Tear down ASH Subsystem... END REM ************************************************************* REM Title Loop... (Display our title sequence.) REM ************************************************************* REM Animate in our initial screen layout and then perform a cycle REM between Credits, Score Advance, Keyboard Controls & HiScore REM Table screens. Do a keyboard scan for each screen and check REM for hotkeys and return from function accordingly... Object REM hwind% points to the area of the screen where where the REM current screen in the sequence gets placed in the attract REM mode. Although not a window in the true sense, in that it has REM no focus, it's easier to think of it that way. This is the REM area below "Invaders" and above "PRESS SPACE TO PLAY" text. REM Objects inv1% - inv3% are identical copies of each other, REM except for values of ypos%. Likewise, the key-% objects are REM copies, apart from the co-ordinates. Our saucer% object here, REM is only large enough to hold screen co-ordinates. It is made REM LOCAL to this function so we can re-define it for the main REM game loop. DEFFNtitle_loop LOCAL i%,space%,invt%,hwind%,str%,saucer%,inv1%,inv2%,inv3% LOCAL base%,keyz%,keyx%,keye%,keyq%,keym%,keys%,keyu%,keyd% LOCAL x%,y%,rc%,scores_save%,s$,string$ scores_save%=44 :REM gamestate% object offsets. REM Allocate & initialise title sequence objects using ASH... REM Space is allocated for keyx%, keye%, keyq%, keym%, keys%, REM keyu%, keyd%, inv2% and inv3% by FNash_blockcopy() all we REM need to do is remember to release it afterwards. space% =FNash_claimfilled(16,0) invt% =FNash_claimfilled(16,0) hwind% =FNash_claimfilled(16,0) saucer% =FNash_claimfilled(16,0) inv1% =FNash_claimfilled(16,0) keyz% =FNash_claimfilled(16,0) base% =FNash_claimfilled(16,0) REM Initialise LOCAL (title sequence) variables. space%!xsize%=FNconv_units(100,1) :REM Space text properties. space%!ysize%=FNconv_units(40,2) space%!xpos%=FNcentre_sprite(space%,screen%) space%!ypos%=800 invt%!xsize%=FNconv_units(150,1) :REM Invaders text properties. invt%!ysize%=FNconv_units(40,2) invt%!xpos%=FNcentre_sprite(invt%,screen%) invt%!ypos%=space%!ypos%-invt%!ysize% hwind%!xsize%=720:hwind%!ysize%=500:REM Window properties. hwind%!xpos%=FNcentre_sprite(hwind%,screen%) hwind%!ypos%=200 saucer%!xsize%=FNconv_units(40,1) :REM Saucer properties. saucer%!ysize%=FNconv_units(20,2) saucer%!xpos%=(hwind%!xpos%+hwind%!xsize%/2)-150 saucer%!ypos%=(hwind%!ypos%+hwind%!ysize%)-125 base%!xsize%=FNconv_units(30,1) :REM Base properties. base%!ysize%=FNconv_units(15,2) inv1%!xsize%=FNconv_units(20,1) :REM Common invader props. inv1%!ysize%=FNconv_units(20,2) inv1%!xpos%=(hwind%!xpos%+hwind%!xsize%/2)-150 inv1%!xpos%+=FNcentre_sprite(inv1%,saucer%) inv2%=FNash_blockcopy(inv1%) :REM Create two copies. inv3%=FNash_blockcopy(inv1%) :REM Unique invader props. inv3%!ypos%=saucer%!ypos%-40-inv3%!ysize% inv2%!ypos%=inv3%!ypos%-40-inv2%!ysize% inv1%!ypos%=inv2%!ypos%-40-inv1%!ysize% keyz%!xsize%=FNconv_units(20,1) :REM KB Controls "keys". keyz%!ysize%=FNconv_units(20,2) keyz%!xpos%=(hwind%!xpos%+hwind%!xsize%/2)-120 keyx%=FNash_blockcopy(keyz%) :REM Clone three. keye%=FNash_blockcopy(keyz%):keyq%=FNash_blockcopy(keyz%) keyq%!xpos%=hwind%!xpos% :REM Tweak & clone three. keyp%=FNash_blockcopy(keyq%):keys%=FNash_blockcopy(keyq%) keym%=FNash_blockcopy(keyz%) keym%!xpos%=hwind%!xpos% :REM Tweak & clone two. keym%!xpos%+=(hwind%!xsize%/2)+10 keyu%=FNash_blockcopy(keym%):keyd%=FNash_blockcopy(keym%) :REM Unique "keys" props. keyz%!ypos%=(hwind%!ypos%+hwind%!ysize%)-120 keyx%!ypos%=keyz%!ypos%-60:keye%!ypos%=keyx%!ypos%-60 keys%!ypos%=keye%!ypos%-90:keyp%!ypos%=keys%!ypos%-60 keyq%!ypos%=keyp%!ypos%-60:keym%!ypos%=keye%!ypos%-90 keyu%!ypos%=keym%!ypos%-60:keyd%!ypos%=keyu%!ypos%-60 REM Animate the initial screen title "Space Invaders" & "PRESS REM SPACE TO PLAY" messages. CLS:PROCdraw_rail(rail%!toprail%):PROCdraw_rail(rail%!baserail%) PROChud_soundstate FOR i%=0-space%!xsize% TO space%!xpos% STEP 5 WAIT:PROCplot(FNsprite_get(100),i%,space%!ypos%) PROCwait(1) NEXT i% FOR i%=screen%!xsize% TO invt%!xpos% STEP -5 WAIT:PROCplot(FNsprite_get(101),i%,invt%!ypos%) PROCwait(1) NEXT i% string$=FNstring_get(32):str%=LEN(string$)*screen%!xfont%:y%=170 PROCprint(FNcentre_text(str%,screen%!xsize%),y%,string$,11) string$=FNstring_get(33) str%=LEN(string$)*screen%!xfont%:y%-=screen%!yfont% PROCprint(FNcentre_text(str%,screen%!xsize%),y%,string$,11) REM Cycle the remainder of the attract mode. WHILE NOT INKEY(-99) AND NOT INKEY(-17) AND NOT INKEY(-82) REM Display Credits Screen... REM Text strings are held in cred_str$() in encrypted form. REM Line spacing info is held in the matching element of REM cred_spc%(). Negative values have special meanings... REM Value | Line spacing is... REM --------+--------------------- REM -1 | 1 * screen%!yfont% (Next line.) REM -2 | 2 * screen%!yfont% (Leave a blank line.) REM <+n> | Leave a gap of OS Units... y%=hwind%!ypos%+hwind%!ysize% FOR i%=1 TO cred_size% string$=FNencode_string(cred_str$(i%)) x%=FNtitle_stringcentre(string$) CASE cred_spc%(i%) OF WHEN -1 : y%-=screen%!yfont% WHEN -2 : y%-=(2*screen%!yfont%) OTHERWISE : y%-=cred_spc%(i%) ENDCASE PROCprint(x%,y%,string$,0) NEXT i% REM Wait for 750 counts or until SPACE or Q pressed... rc%=FNtitle_wait IF rc%=1 THEN =TRUE IF rc%=2 THEN =FALSE PROCwipe_sprite(hwind%) REM Display Score Advance table... string$=FNstring_get(57)+" "+FNstring_get(34) x%=FNtitle_stringcentre(string$) y%=hwind%!ypos%+hwind%!ysize%-20:PROCprint(x%,y%,string$,0) string$=FNstring_get(35):y%-=screen%!yfont% x%=FNtitle_stringcentre(string$):PROCprint(x%,y%,string$,0) x%=saucer%!xpos%+saucer%!xsize%+10 PROCplot(FNsprite_get(11),saucer%!xpos%,saucer%!ypos%) string$=FNstring_get(36)+" "+FNstring_get(40) PROCprint(x%,saucer%!ypos%+10,string$,0) PROCplot(FNsprite_get(24),inv3%!xpos%,inv3%!ypos%) string$=FNstring_get(37)+" "+FNstring_get(40) PROCprint(x%,inv3%!ypos%+12,string$,0) PROCplot(FNsprite_get(22),inv2%!xpos%,inv2%!ypos%) string$=FNstring_get(38)+" "+FNstring_get(40) PROCprint(x%,inv2%!ypos%+12,string$,0) PROCplot(FNsprite_get(20),inv1%!xpos%,inv1%!ypos%) string$=FNstring_get(39)+" "+FNstring_get(40) PROCprint(x%,inv1%!ypos%+12,string$,0) str%=base%!xsize%/screen%!xfont%+2:s$=FNstring_get(66) string$=s$+STRING$(str%," ")+FNstring_get(67) x%=FNtitle_stringcentre(string$) y%=inv1%!ypos%-(3*screen%!yfont%) PROCprint(x%,y%,string$,0) base%!xpos%=x%+7+(LEN(s$)*screen%!xfont%):base%!ypos%=y% PROCplot(FNsprite_get(1),base%!xpos%,base%!ypos%) REM Wait for 750 counts or until SPACE or Q pressed... rc%=FNtitle_wait IF rc%=1 THEN =TRUE IF rc%=2 THEN =FALSE PROCwipe_sprite(hwind%) REM Display Keyboard controls screen... string$=FNstring_get(41):x%=FNtitle_stringcentre(string$) y%=hwind%!ypos%+hwind%!ysize%-20:PROCprint(x%,y%,string$,0) REM Left, Right & Fire... x%=keyz%!xpos%+keyz%!xsize%+10 PROCplot(FNsprite_get(102),keyz%!xpos%,keyz%!ypos%) :REM (Z) string$=FNstring_get(42)+" "+FNstring_get(43) PROCprint(x%,keyz%!ypos%+12,string$,0) PROCplot(FNsprite_get(103),keyx%!xpos%,keyx%!ypos%) :REM (X) string$=FNstring_get(42)+" "+FNstring_get(44) PROCprint(x%,keyx%!ypos%+12,string$,0) PROCplot(FNsprite_get(104),keye%!xpos%,keye%!ypos%) :REM (Enter) PROCprint(x%,keye%!ypos%+12,FNstring_get(45),0) REM Extra control keys (Left column)... x%=keyq%!xpos%+keyq%!xsize%+10 PROCplot(FNsprite_get(105),keyp%!xpos%,keyp%!ypos%) :REM (P) string$=FNstring_get(46)+" "+FNstring_get(49) PROCprint(x%,keyp%!ypos%+12,string$,0) PROCplot(FNsprite_get(117),keys%!xpos%,keys%!ypos%) :REM (S) PROCprint(x%,keys%!ypos%+12,FNstring_get(76),0) PROCplot(FNsprite_get(107),keyq%!xpos%,keyq%!ypos%) :REM (Q) string$=FNstring_get(48)+" "+FNstring_get(49) PROCprint(x%,keyq%!ypos%+12,string$,0) REM Extra control keys (Right column)... x%=keym%!xpos%+keym%!xsize%+10 PROCplot(FNsprite_get(106),keym%!xpos%,keym%!ypos%) :REM (M) string$=FNstring_get(47)+" "+FNstring_get(73) PROCprint(x%,keym%!ypos%+12,string$,0) PROCplot(FNsprite_get(115),keyu%!xpos%,keyu%!ypos%) :REM (+) string$=FNstring_get(47)+" "+FNstring_get(77)+" " string$+=FNstring_get(74) PROCprint(x%,keyu%!ypos%+12,string$,0) PROCplot(FNsprite_get(116),keyd%!xpos%,keyd%!ypos%) :REM (-) string$=FNstring_get(47)+" "+FNstring_get(77)+" " string$+=FNstring_get(75) PROCprint(x%,keyd%!ypos%+12,string$,0) REM Wait for 750 counts or until SPACE or Q pressed... rc%=FNtitle_wait IF rc%=1 THEN =TRUE IF rc%=2 THEN =FALSE PROCwipe_sprite(hwind%) REM Display HiScore table... REM First line... (This is conditional on scores_save%) string$=FNstring_get(50) IF gamestate%!scores_save% THEN string$=FNstring_get(51) x%=FNtitle_stringcentre(string$) y%=hwind%!ypos%+hwind%!ysize%-20 PROCprint(x%,y%,string$,0) REM Second line... string$=FNstring_get(58)+" "+FNstring_get(52) x%=FNtitle_stringcentre(string$):y%-=screen%!yfont% PROCprint(x%,y%,string$,0) REM Table header... y%=(hwind%!ypos%+hwind%!ysize%)-100 string$=" "+FNstring_get(68)+" "+FNstring_get(69) string$+=STRING$(12," ")+FNstring_get(57)+"." string$+=STRING$(3," ")+FNstring_get(60)+"." x%=FNtitle_stringcentre(string$) PROCprint(x%,y%,string$,0) y%-=2*screen%!yfont% REM Loop through the HiScore table arrays displaying names and REM scores... FOR i%=1 TO 10 IF i%<10 THEN string$=" "+STR$(i%)+". " ELSE string$=" "+STR$(i%)+". " ENDIF s$=FNencode_string(scores_name$(i%)) string$+=FNstr_pad(s$,8," ",FALSE):string$+=" .... " string$+=FNstr_rightalign(STR$(scores_value%(i%)),10) string$+=" ... "+FNstr_rightalign(STR$(scores_rack%(i%)),3) x%=FNtitle_stringcentre(string$) PROCprint(x%,y%-(i%*(screen%!yfont%+5)),string$,0) NEXT i% REM Wait for 750 counts or until SPACE or Q pressed... rc%=FNtitle_wait IF rc%=1 THEN =TRUE IF rc%=2 THEN =FALSE PROCwipe_sprite(hwind%) ENDWHILE REM This should never get executed... ERROR 255,FNstring_get(102) =FALSE REM Wait for 750 counts or SPACE or Q to be pressed. Returns one REM of three values in rc% REM 0 -> Timeout period expired... (750 counts up.) REM 1 -> "Q" to Quit... REM 2 -> SPACE to Play... DEFFNtitle_wait LOCAL t%,rc% t%=TIME+750:rc%=FALSE REPEAT IF INKEY(-82) THEN PROCevnt_kb_screendump IF INKEY(-102) THEN PROCevnt_kb_togglemusic IF INKEY(-59) THEN PROCevnt_kb_volume(4) IF INKEY(-60) THEN PROCevnt_kb_volume(-4) UNTIL TIME>=t% OR INKEY(-17) OR INKEY(-99) IF INKEY(-17) THEN rc%=1 :REM Get outta here (Q)... IF INKEY(-99) THEN rc%=2 :REM Play a game... REM If rc% is TRUE (non zero value) then we either start a game REM or quit. Either way, we need to release the memory claimed REM by our objects. IF rc% THEN PROCash_free(space%):PROCash_free(invt%):PROCash_free(hwind%) PROCash_free(saucer%):PROCash_free(inv1%):PROCash_free(inv2%) PROCash_free(inv3%):PROCash_free(keyz%):PROCash_free(keyx%) PROCash_free(keye%):PROCash_free(keyq%):PROCash_free(keym%) PROCash_free(keyp%):PROCash_free(keys%):PROCash_free(keyu%) PROCash_free(keyd%):PROCash_free(base%) ENDIF =rc% REM Prepare a string for display... REM Centering a string requires a number of parameters to be setup REM before calling PROCprint(). The process is largely repetative REM All we do is change a few values. DEFFNtitle_stringcentre(string$) LOCAL str% str%=LEN(string$)*screen%!xfont% =hwind%!xpos%+FNcentre_text(str%,hwind%!xsize%) REM ************************************************************* REM Game Loop... (Play one instance of the game.) REM ************************************************************* REM Loop through one instance of the game. This basically means... REM Setup in-game stuff. -> Play until out of bases. -> Manage REM hiscore entry. -> Return. DEFPROCmain LOCAL base%,shell%,saucer%,rack%,player% :REM Objects. LOCAL inv% LOCAL invstat%(),invfire%() :REM Invader status. LOCAL bunker%(),bunknum% :REM Bunker status. LOCAL lives%,score%,racknum%,suicide% :REM Player properties. LOCAL paused%,pstatus%,ptime% :REM Game state (Paused) LOCAL elcount% :REM Game state (Extra) LOCAL colgap%,xnum%,ynum%,rownum%,frcap% :REM Rack properties. LOCAL evnt_kb%,str%,string$,x%,y%,i%,j% :REM Misc. REM Claim memory for local objects using ASH... base%=FNash_claim(32):shell%=FNash_claim(28) saucer%=FNash_claim(48):rack%=FNash_claim(68) inv%=FNash_claim(16):player%=FNash_claimfilled(16,0) REM Setup arrays and object pointers... lives%=0:score%=4:racknum%=8:suicide%=12 :REM Player offsets. elcount%=16:paused%=28:bunknum%=56 :REM Game state offs. colgap%=flags2%:xnum%=flags3%:ynum%=flags4% :REM Rack offsets. rownum%=flags7%:frcap%=flags8% DIM invstat%(10,6),invfire%(10),bunker%(gamestate%!bunknum%) REM Initialise LOCAL (in-game) variables. base%!xsize%=FNconv_units(30,1) :REM Base properties. base%!ysize%=FNconv_units(15,2) base%!xpos%=FNcentre_sprite(base%,screen%) base%!ypos%=50:base%!speed%=6:base%!dir%=base%!speed% inv%!xsize%=FNconv_units(20,1) :REM Invader properties. inv%!ysize%=FNconv_units(20,2) saucer%!xsize%=FNconv_units(40,1) :REM Saucer properties. saucer%!ysize%=FNconv_units(20,2) saucer%!ypos%=rail%!toprail%-(10+saucer%!ysize%) saucer%!speed%=5:saucer%!active%=FALSE saucer%!flags3%=1 shell%!xsize%=FNconv_units(5,1) :REM Shell properties. shell%!ysize%=FNconv_units(20,2) shell%!active%=FALSE:shell%!speed%=10 player%!racknum%=1:player%!lives%=3 :REM Player properties. player%!suicide%=FALSE gamestate%!elcount%=-1 :REM Initial game state. rack%!colgap%=FNconv_units(20,1) :REM Rack properties. rack%!xnum%=10:rack%!ynum%=6 rack%!active%=TRUE:rack%!frcap%=4 SYS FNswi_get(6) TO rack%!flags9% PROCinvfire_init:PROCbunk_init :REM Object arrays. REM Initialise game screen... REM Draw the top and bottom rails, prepare and display the HUD & REM sort out the first rack of invaders. Finally... Display the REM player's base. PROCdraw_rail(rail%!toprail%):PROCdraw_rail(rail%!baserail%) PROChud_init(0,scores_value%(1),player%!lives%,player%!racknum%) PROCrack_gameinit :REM Invaders. PROCbunk_redraw :REM Bunkers. PROCplot(FNsprite_get(1),base%!xpos%,base%!ypos%) :REM Base. REM Our event generator... REM This is the main polling loop. The program sits tight in this REM loop firing off events until the player runs out of lives. WHILE player%!lives%>0 REM Keyboard poll... REM We only check the top four if we haven't paused the game. REM The rest we always need to check. evnt_kb%=FALSE IF gamestate%!paused%=0 THEN IF INKEY(-74) THENPROCevnt_kb_basefire(base%!xpos%,base%!ypos%) IF INKEY(-98) THENPROCevnt_kb_baseleft:evnt_kb%=TRUE IF INKEY(-67) THENPROCevnt_kb_baseright:evnt_kb%=TRUE IF INKEY(-17) THENPROCevnt_kb_suicide :REM(Q)Suicide... REMIF INKEY(-36) THENPROCevnt_kb_saucertest :REM(T)Test only... REMIF INKEY(-87) THENPROCevnt_kb_eltest :REM(L)Test only... REMIF INKEY(-35) THENPROCrack_endgame :REM(E)Test only... ENDIF IF INKEY(-102)THENPROCevnt_kb_togglemusic :REM(M)Music On/Off IF INKEY(-82) THENPROCevnt_kb_screendump :REM(S)Screenshot... IF INKEY(-56) THENPROCevnt_kb_togglepause :REM(P)Pause Game... IF INKEY(-59) THENPROCevnt_kb_volume(4) :REM(+)Volume Up... IF INKEY(-60) THENPROCevnt_kb_volume(-4) :REM(-)Volume Down... REM Update screen... REM This is our equivalent of an arcade game's VBlank interrupt. REM We've polled the input device (our keyboard) and we're REM idling whilst processing events (evnt_kb%=FALSE). Either REM way, something's going on, usually AI/Collision detection REM related. REM Post-process evnt_kb event updates. (Keyboard.) REM The only two that require action here are left & right as REM we need to display the base at the new position. IF gamestate%!paused%=0 THEN IF evnt_kb% THEN base%!xpos%+=base%!dir% PROCplot(FNsprite_get(1),base%!xpos%,base%!ypos%) ENDIF ENDIF REM Process evnt_fr events. (Frame Refresh.) IF gamestate%!paused%=0 THEN PROCevnt_fr_basefire :REM Animate player's shots. PROCevnt_fr_saucer :REM Saucer handling & AI. PROCevnt_fr_rackmove :REM Move rack & Collision detect. PROCevnt_fr_rackfire :REM Rack missile fire control. PROCevnt_fr_bunkers :REM Defense bunker collision stuff. PROCevnt_fr_extralife :REM "Extra Life" text control. ELSE PROCevnt_fr_pausegame :REM "Game Paused" text control. ENDIF REM Wait for next VBlank WAIT ENDWHILE REM Display GAME OVER!!! in a bordered rectangle in the middle REM of the screen. box%!xsize%=240:box%!ysize%=40 box%=FNcentre_sprite_xy(box%,screen%):box%!ypos%-=3 PROCwipe_sprite(box%):PROCdraw_box(box%) string$=FNstring_get(49)+" "+FNstring_get(53) PROCcentre_text_xy(string$,11):PROCwait(750) REM Check & Handle HiTable entry... IF NOT player%!suicide% THEN IF player%!score%>=scores_value%(10) THEN PROChitable_entry(player%) ENDIF ENDIF REM Free memory used for objects... PROCash_free(base%):PROCash_free(rack%):PROCash_free(saucer%) PROCash_free(shell%):PROCash_free(player%):PROCash_free(inv%) FOR i%=1 TO 10:PROCash_free(invfire%(i%)):NEXT i% FOR i%=1 TO gamestate%!bunknum%:PROCash_free(bunker%(i%)):NEXT i% ENDPROC REM ************************************************************* REM Proceedures (Keyboard events.) REM ************************************************************* REM Move base left. If we're already at left edge then bail... DEFPROCevnt_kb_baseleft REM Collision detection. (Base & Playfield.) IF base%!xpos%<=0 THEN base%!xpos%=0 :REM Don't move. ELSE base%!dir%=0-base%!speed% :REM Change direction. ENDIF ENDPROC REM Move base right. If we're already at the right edge, bail... DEFPROCevnt_kb_baseright REM Collision detection. (Base & Playfield.) IF base%!xpos%>=screen%!xsize%-base%!xsize% THEN base%!xpos%=screen%!xsize%-base%!xsize% :REM Don't move. ELSE base%!dir%=0+base%!speed% :REM Change direction. ENDIF ENDPROC REM Fire a shell. If we're already firing a shell bail. (We can REM only fire one shell at a time or else the animation gets REM confused.) shell%!active% is a property of the shell% object REM that is set boolean TRUE when player fires a shell and is REM cleared when either the shell scrolls off the top of the REM screen or hits something. DEFPROCevnt_kb_basefire(x%,y%) REM Bail if shell already active. IF NOT shell%!active% THEN shell%!active%=TRUE :REM Set active. shell%!xpos%=x%+(base%!xsize%/2) :REM Initial position. shell%!ypos%=y%+base%!ysize% PROCsfx_play(4) ENDIF ENDPROC REM Dump a screen to disc as ".Screens.Dump" REM Where is a number from 0 to 999. FNinit_setdumpcounter() REM when given the current value, returns the next free slot. REM When the "Screens" directory is empty, we start from 0. DEFPROCevnt_kb_screendump LOCAL num%,mflag%,name$ num%=40:mflag%=44 :REM Object offsets. IF gamestate%!mflag% THEN REPEAT:UNTIL NOT INKEY(-82) :REM De-bounce key. gamestate%!num%=FNinit_setdumpcounter(gamestate%!num%) IF gamestate%!num%=-1 THEN ERROR255,FNstring_get(109) name$=".Screens.Dump"+STR$(gamestate%!num%) OSCLI"ScreenSave "+name$ ENDIF ENDPROC REM Player has chickened out. (Committed suicide. 'Q' in-game.) REM Set lives to zero and flag it up as a suicide event in the REM player object. (Skip Hiscore entry if suicide set.) DEFPROCevnt_kb_suicide LOCAL i% FOR i%=1 TO 7:invfire%(i%)!active%=FALSE:NEXT i% player%!lives%=0:player%!suicide%=TRUE ENDPROC REM Toggle Music on & off... REM Added music% object data to new gamestate% object, which now REM also includes some of the values we used to store with the REM player% object that were never really specific to the player, REM but didn't belong anywhere else either. (04/07/08) REM Offs. | Purpose | Value REM -------+----------+------ REM 0 | Status | 0=Mute, 1=Music & SFX, 2=SFX Only. REM 4 | Handle | TimPlayer internal handle. REM 8 | Delay | Snapshot of OS_ReadMonotonicTime last done DEFPROCevnt_kb_togglemusic LOCAL mstatus%,mhandle% mstatus%=0:mhandle%=4 REPEAT:UNTIL NOT INKEY(-102) :REM De-bounce key. gamestate%!mstatus%+=1 IF gamestate%!mstatus%>2 THEN gamestate%!mstatus%=0 IF gamestate%!mstatus%=1 THEN SYSFNswi_get(33),gamestate%!mhandle% ELSE SYSFNswi_get(34),gamestate%!mhandle% ENDIF PROChud_soundstate ENDPROC REM Turn Music volume up/down... REM We only need to do this if music is actually playing... Don't REM change anything otherwise. We don't de-bounce the keys here REM as we don't exactly want a one-shot event. We do however, need REM to introduce a delay, otherwise we would get an on/off switch REM situation on fast hardware. DEFPROCevnt_kb_volume(vol%) LOCAL mstatus%,mhandle%,mdelay%,mt%,cvol%,nvol% mstatus%=0:mhandle%=4:mdelay%=8 :REM Object offsets. IF gamestate%!mstatus%=1 THEN SYSFNswi_get(6) TO mt% :REM OS_ReadMonotonicTime IF mt%-gamestate%!mdelay%>=10 THEN SYSFNswi_get(36),gamestate%!mhandle%,-1 TO ,cvol% nvol%=cvol%+vol% IF nvol%>=0 AND nvol%<=128 THEN SYSFNswi_get(36),gamestate%!mhandle%,nvol% gamestate%!mdelay%=mt% ENDIF ENDIF ENDIF ENDPROC REM Pause & Resume game... REM Toggle between pause and resume. The actual logic is done REM elsewhere. DEFPROCevnt_kb_togglepause LOCAL paused%,pstatus%,string$ paused%=28:pstatus%=32 REPEAT UNTIL NOT INKEY(-56) :REM De-bounce. string$=FNstring_get(49)+" "+FNstring_get(61) gamestate%!paused%=FNtoggle(gamestate%!paused%) :REM Toggle. gamestate%!pstatus%=gamestate%!paused% :REM Set visible. IF gamestate%!paused%=0 THEN string$=STRING$(LEN(string$)," ") PROChud_bannertext(string$) ENDIF ENDPROC REM ************************************************************* REM Proceedures (VBlank/Frame Events) REM ************************************************************* REM Continue animation of a player's shell... If one hasn't been REM created then we bail back to event loop. DEFPROCevnt_fr_basefire IF shell%!active% THEN REM Have we hit the top?? IF shell%!ypos%>=rail%!toprail%-shell%!ysize% THEN shell%!active%=FALSE :REM Clear event. shell%!ypos%-=2:PROCwipe_sprite(shell%) :REM Remove shell. ELSE REM Display shell at current position. PROCplot(FNsprite_get(5),shell%!xpos%,shell%!ypos%) ENDIF shell%!ypos%+=shell%!speed% :REM Advance frame. ENDIF ENDPROC REM Process saucer animation & generation events. A saucer can be REM randomely activated n% of the time, but not if one is REM currently on the screen. When activated, there is a 50% chance REM of it starting on the left hand side of the screen, likewise REM we have a 50% chance of it starting on the right. DEFPROCevnt_fr_saucer LOCAL hit%,toggle%,spr%,mt%,hittime%,fr$ hit%=flags1%:toggle%=flags2%:spr%=flags3% :REM Object tokens. IF NOT saucer%!active% THEN IF FNpct(4) AND FNpct(5) THEN saucer%!active%=TRUE:saucer%!beenhit%=FALSE saucer%!toggle%=0 REM Decide which side of the screen to start from. IF FNpct(50) THEN saucer%!dir%=0-saucer%!speed% :REM Right edge. (50%) saucer%!xpos%=screen%!xsize% ELSE saucer%!dir%=0+saucer%!speed% :REM Left edge. (50%) saucer%!xpos%=0-saucer%!xsize% ENDIF ENDIF ELSE REM Has saucer gone off screen?? IF saucer%!xpos%<=0-saucer%!xsize%ANDSGN(saucer%!dir%)=-1 THEN saucer%!hit%=FALSE:saucer%!active%=FALSE ENDPROC ENDIF IF saucer%!xpos%>screen%!xsize%ANDSGN(saucer%!dir%)=1 THEN saucer%!hit%=FALSE:saucer%!active%=FALSE ENDPROC ENDIF REM Has saucer been hit by player shot?? IF NOT saucer%!beenhit% THEN IF FNhit(shell%,saucer%) THEN PROCwipe_sprite(shell%) PROCplot(FNsprite_get(12),saucer%!xpos%,saucer%!ypos%) SYS FNswi_get(6) TO saucer%!hit%:saucer%!beenhit%=TRUE shell%!active%=FALSE:PROChud_scorehit(500) ENDIF ELSE IF FNhit(shell%,saucer%) THEN PROCwipe_sprite(shell%):shell%!active%=FALSE ENDIF ENDIF REM Animate saucer... IF NOT saucer%!beenhit% THEN REM Change image every 40 centi-seconds. SYS FNswi_get(6) TO mt% :REM OS_ReadMonotonicTime IF mt%-saucer%!spr%>=40 THEN saucer%!spr%=mt% saucer%!toggle%=FNtoggle(saucer%!toggle%) ENDIF REM Display one of two images. fr$=FNsprite_get(10)+STR$(saucer%!toggle%) PROCplot(fr$,saucer%!xpos%,saucer%!ypos%) saucer%!xpos%+=saucer%!dir% ELSE REM Animate/Remove explosion... SYS FNswi_get(6) TO mt% hittime%=mt%-saucer%!hit% IF hittime%>=300 THEN saucer%!active%=FALSE:saucer%!toggle%=1 PROCwipe_sprite(saucer%) ELSE IF hittime%>=250 THEN PROCplot(FNsprite_get(15),saucer%!xpos%,saucer%!ypos%) ELSE IF hittime%>=200 THEN PROCplot(FNsprite_get(14),saucer%!xpos%,saucer%!ypos%) ELSE IF hittime%>=100 THEN PROCplot(FNsprite_get(13),saucer%!xpos%,saucer%!ypos%) ENDIF ENDIF ENDIF ENDIF ENDIF ENDIF ENDPROC REM Check out the rack of invaders. Move left, right & down. Deal REM with collision detection between player missiles and invaders. DEFPROCevnt_fr_rackmove LOCAL rack_ext%,z%,col%,row%,eclr%,sclr%,rclr%,offset% LOCAL frame%,scol%,ecol%,mt%,timer%,pcsinv%,pcsbnk% REM Setup meaningful pointers to our object flags... REM Vars colgap%, xnum%, ynum%, rownum% & frcap% have already REM been tied to flags2%, flags3%, flags4%, flags7% & flags8% REM respectively. frame%=flags1%:scol%=flags5%:ecol%=flags6%:timer%=flags9% pcsinv%=52:pcsbnk%=56 REM Alternate our animation frame... SYS FNswi_get(6) TO mt% :REM OS_ReadMonotonicTime IF mt%-rack%!timer%>=50 THEN rack%!timer%=mt%:rack%!frame%=FNtoggle(rack%!frame%) ENDIF REM Deal with rack movement... REM Move rack left, right & down. Check each time we move down REM to make sure that the rack hasn't invaded the base. If it has REM then end the game. rack_ext%=rack%!xpos%+rack%!xsize% offset%=0-((rack%!scol%-1)*(inv%!xsize%+rack%!colgap%)) IF rack_ext%>=screen%!xsize% THEN rack%!dir%=0-rack%!speed%:PROCrack_advance ENDIF IF rack%!xpos%<=offset% THEN rack%!dir%=0+rack%!speed%:PROCrack_advance ENDIF REM Have we reached the base? offset%=rack%!ypos%+((rack%!rownum%-1)*inv%!ysize%) IF offset%<=base%!ypos%+base%!ysize% THEN PROCrack_endgame:ENDPROC ENDIF REM Deal with collision detection... REM Firstly we check to see if the player's shell lays somewhere REM inside the rack of invaders. If this is not the case then we REM bail and take no further action this time. However, if we REM are inside the rack (FNhit(shell%,rack%)=TRUE) then we need REM to see what, if anything, we've actually hit. IF FNhit(shell%,rack%) THEN z%=inv%!xsize%+rack%!colgap% IF (shell%!xpos%-rack%!xpos%) MOD z% <= inv%!xsize% THEN REM We've hit something... Find out what. col%=((shell%!ypos%-rack%!ypos%) DIV inv%!ysize%)+1 row%=((shell%!xpos%-rack%!xpos%) DIV z%)+1 REM Act on it... REM Vars col% & row% now contain the index of the invader that REM the player hit. We now check the status of that invader REM and act accordingly. A value of zero indicates that it's REM already dead and buried, whilst a negative value is used REM as a countdown timer for the explosion sprite. We are only REM interested in positive non-zero values. Anything else, we REM take no action. IF SGN(invstat%(row%,col%))=1 THEN invstat%(row%,col%)=-5 :REM Set explosion timer. PROCwipe_sprite(shell%) :REM Remove shell. shell%!active%=FALSE :REM De-activate shell. rack%!beenhit%+=1 :REM Another one down. PROCsfx_play(1) REM Scoring... CASE col% OF WHEN 1,2 : PROChud_scorehit(50) :REM Bottom two rows. WHEN 3,4 : PROChud_scorehit(75) :REM Middle two rows. WHEN 5,6 : PROChud_scorehit(100) :REM Top two rows. ENDCASE ENDIF ENDIF ENDIF REM Have we destroyed the last invader in the current rack? REM If so, clear the play area and create and display the next REM wave. In the process of clearing the play area, we seem to REM wipe part of the HUD too. This happens when the cleared rows REM drop below the position of the rail marking the bottom of the REM play area. For the moment, I am just re-drawing this as and REM when it happens, but really it needs fixing. IF rack%!beenhit%>=rack%!xnum%*rack%!ynum% THEN player%!racknum%+=1 :REM Advance rack counter. PROCwipe_sprite(rack%) :REM Clear the last invader. PROCdraw_rail(rail%!baserail%) :REM Re-draw bottom rail. PROChud_lives(player%!lives%) :REM Update HUD. PROChud_rack(player%!racknum%) PROChud_soundstate PROCplot(FNsprite_get(1),base%!xpos%,base%!ypos%) PROCbunk_reset:PROCbunk_redraw :REM Reset & redraw bunkers. PROCrack_init :REM Create new rack. REM Increase difficulty by allowing more invader missiles as REM number of racks destroyed increases. IF player%!racknum%>5 THEN gamestate%!pcsinv%=7 IF player%!racknum%>10 THEN gamestate%!pcsinv%=10 ENDIF REM Do we need to resize the rack? The rack is defined as a block REM of a fixed size. We display the invaders in this block. Each REM time we clear the left or rightmost column or the bottom row, REM we need to update the size of this block to keep the display REM accurate. eclr%=TRUE:sclr%=TRUE FOR col%=1 TO rack%!ynum% IF invstat%(rack%!ecol%,col%)<>0 THEN eclr%=FALSE IF invstat%(rack%!scol%,col%)<>0 THEN sclr%=FALSE NEXT col% rclr%=TRUE FOR row%=1 TO rack%!xnum% IF invstat%(row%,rack%!rownum%)<>0 THEN rclr%=FALSE NEXT row% IF sclr% THEN rack%!scol%+=1 IF eclr% THEN rack%!xsize%-=(inv%!xsize%+rack%!colgap%):rack%!ecol%-=1 ENDIF IF rclr% THEN rack%!rownum%+=1 REM Finally... Redraw the rack... rack%!xpos%+=rack%!dir%:PROCrack_redraw ENDPROC REM Invader missile fire logic... REM This... Like all the rest of these animation routines is REM timer based. We call this event handler once every REM repetition of the game loop. All invader missile information REM is held in our invfire%() array. This array is just an array REM of object pointers. Data can be accessed using offsets just REM like all the others. Every call to this event advances the REM animation by one frame and then handles display & collision REM detection for that frame before returning. DEFPROCevnt_fr_rackfire LOCAL i%,j%,mt%,pcsinv%,pcsbnk% REM Assign meaningful names to object specific flags. pcsinv%=52:pcsbnk%=56 REM Loop through all invader missile slots... FOR i%=1 TO gamestate%!pcsinv% IF NOT invfire%(i%)!active% THEN PROCinvfire_create(i%) :REM Create a missile. ELSE PROCinvfire_animate(i%) :REM Animate and move down. REM Collision Detection... REM One of three events can happen here. Either we hit the REM bottom of the playfield, the player's base, or a shell REM hits us on the way up. REM Have we reached the bottom?? IF invfire%(i%)!ypos%<=rail%!baserail%+(rail%!ysize%+5) THEN invfire%(i%)!active%=FALSE:PROCwipe_sprite(invfire%(i%)) ENDIF REM Have we hit the player's base?? IF FNhit(invfire%(i%),base%) AND invfire%(i%)!active% THEN PROCinvfire_hitbase(i%) ENDIF REM Have we hit a bunker?? REM Currently just remove the missile. Replace this bit when REM we've worked out how to do a proper collision detection on REM it. FOR j%=1 TO gamestate%!pcsbnk% IF FNhit(invfire%(i%),bunker%(j%)) THEN PROCbunk_beenhit(j%,FALSE) PROCwipe_sprite(invfire%(i%)):invfire%(i%)!active%=FALSE ENDIF NEXT j% REM Has a shell hit us?? IF FNhit(shell%,invfire%(i%)) THEN PROCinvfire_beenhit(i%) ENDIF REM Explosion frame... IF invfire%(i%)!beenhit% THEN PROCinvfire_explode(i%) ENDIF ENDIF NEXT i% ENDPROC REM Handle the pause status and update the HUD... REM Text display is carried out by a HUD routine. We need to check REM and fire it here only... DEFPROCevnt_fr_pausegame LOCAL paused%,pstatus%,ptime%,mt%,string$ paused%=28:pstatus%=32:ptime%=36 :REM Object offsets. SYS FNswi_get(6) TO mt% IF mt%-gamestate%!ptime%>=50 THEN gamestate%!pstatus%=FNtoggle(gamestate%!pstatus%) gamestate%!ptime%=mt% ENDIF string$=FNstring_get(49)+" "+FNstring_get(61) :REM "GAME PAUSED" IF gamestate%!pstatus%=0 OR gamestate%!paused%=0 THEN string$=STRING$(LEN(string$)," ") ENDIF PROChud_bannertext(string$) ENDPROC REM Handle the extra life text status and update the HUD... REM This routine is fired if player%!elcount% is zero or greater. REM When our count (player%!elcount%) gets above 5, we set it to REM -1... It is then triggered in the scoring routine when an REM extra life condition occurs by setting our count to 0. Our REM current state (either blink on, or blink off) is held as 1 or REM 0 in player%!elframe%. DEFPROCevnt_fr_extralife LOCAL elcount%,elframe%,eltime%,mt%,string$ elcount%=16:elframe%=20:eltime%=24 :REM Object offsets. IF gamestate%!elcount%>=0 THEN SYS FNswi_get(6) TO mt% string$=FNstring_get(66)+" "+FNstring_get(72) :REM "EXTRA LIFE" IF mt%-gamestate%!eltime%>=50 THEN gamestate%!eltime%=mt% gamestate%!elframe%=FNtoggle(gamestate%!elframe%) IF gamestate%!elframe%=1 THEN gamestate%!elcount%+=1 ENDIF REM Are we in blink off state?? IF gamestate%!elframe%=0 THEN string$=STRING$(LEN(string$)," ") :REM Clear the line... ENDIF REM Have we blinked 5 times?? IF gamestate%!elcount%>5 THEN string$=STRING$(LEN(string$)," ") :REM Clear the line... gamestate%!elcount%=-1 :REM Disable event... ENDIF PROChud_bannertext(string$) :REM Update the HUD... ENDIF ENDPROC REM Deal with the bunkers... REM Currently we destroy the bunker after a combination of 10 REM hits by either the player or the invaders. Each time a bunker REM is hit, we bump it up or down by an offset of 5px accordingly. REM this is a temporary nudge like effect which returns the REM bunker to it's rightful place shortly afterwards. DEFPROCevnt_fr_bunkers LOCAL i%,mt%,pcs%,timer%,blk% pcs%=56:timer%=flags2% :REM Object offsets. blk%=FNash_claim(16) :REM Temp bunker object. FOR i%=1 TO gamestate%!pcs% :REM Loop through each bunker. IF FNhit(shell%,bunker%(i%)) THEN PROCwipe_sprite(shell%):shell%!active%=FALSE PROCbunk_beenhit(i%,TRUE) ENDIF IF bunker%(i%)!beenhit% THEN SYSFNswi_get(6) TO mt% IF mt%-bunker%(i%)!timer%>=5 THEN blk%!xpos%=bunker%(i%)!xpos%:blk%!xsize%=bunker%(i%)!xsize% blk%!ypos%=bunker%(i%)!ypos%-5 blk%!ysize%=bunker%(i%)!ysize%+10:PROCwipe_sprite(blk%) PROCplot(FNsprite_get(16),bunker%(i%)!xpos%,bunker%(i%)!ypos%) bunker%(i%)!beenhit%=FALSE ENDIF ENDIF NEXT i% PROCash_free(blk%) ENDPROC REM ************************************************************* REM Functions & Proceedures. (HiScore Table/HiScore Entry.) REM ************************************************************* REM Create a clean HiScore table. The value passed to us in save% REM determines whether we can save the table to disc or not. If REM we can (save%=TRUE) then we call PROChitable_save to write the REM file back. DEFPROChitable_create(save%) LOCAL i%,n$ FOR i%=1 TO 10 IF i% MOD 2=0 THEN n$=FNstring_get(71) ELSE n$=FNstring_get(70) scores_name$(i%)=FNencode_string(n$) scores_value%(i%)=(11-i%)*1000:scores_rack%(i%)=0 NEXT i% IF save% THEN PROChitable_save ENDPROC REM Load our HiTable from disc. The names are stored in RAM in REM encoded form and are only decoded for display. DEFPROChitable_load LOCAL i%,hdl% hdl%=OPENIN(dat_dir$+"HiTable") FOR i%=1 TO 10 INPUT#hdl%,scores_name$(i%),scores_value%(i%),scores_rack%(i%) NEXT i% CLOSE#hdl% ENDPROC REM Save our HiTable back to disc. The names are stored in RAM in REM encoded form and are only decoded for display. DEFPROChitable_save LOCAL i%,hdl% hdl%=OPENOUT(dat_dir$+"HiTable") FOR i%=1 TO 10 PRINT#hdl%,scores_name$(i%),scores_value%(i%),scores_rack%(i%) NEXT i% CLOSE#hdl% ENDPROC REM HiScore name entry... REM Sort through our hiscore array and find out where the player REM is. (We already know he is worthy.) Allow to enter their name REM and save the HiTable back to disk (Only if scores_save%=TRUE). REM then return... DEFPROChitable_entry(player%) LOCAL invt%,space%,done%,g%,i%,pos%,str%,x%,y%,string$ LOCAL scores_save% space%=FNash_claim(16) :REM Space for objects. invt%=FNash_claim(16) scores_save%=44 :REM gamestate% object offs. REM Setup graphical objects for later on... space%!xsize%=FNconv_units(100,1) :REM Space text properties. space%!ysize%=FNconv_units(40,2) space%!xpos%=FNcentre_sprite(space%,screen%) space%!ypos%=800 invt%!xsize%=FNconv_units(150,1) :REM Invaders text properties. invt%!ysize%=FNconv_units(40,2) invt%!xpos%=FNcentre_sprite(invt%,screen%) invt%!ypos%=space%!ypos%-invt%!ysize% REM Find out where we are and stick it in pos% pos%=0 FOR i%=10 TO 1 STEP -1 IF player%!score%>=scores_value%(i%) THEN pos%=i% NEXT i% REM Insert a new entry into the table and drop everything below REM us by one place... (We are 5th, so old 5th becomes 6th... 9th REM becomes 10th and 10th gets dropped.) We need to do this to REM all three arrays... FOR i%=9 TO pos% STEP -1 scores_name$(i%+1)=scores_name$(i%) scores_value%(i%+1)=scores_value%(i%) scores_rack%(i%+1)=scores_rack%(i%) NEXT i% REM Insert Player's achieved score & rack into the table... scores_value%(pos%)=player%!score% scores_rack%(pos%)=player%!racknum% REM Now deal with the graphics... REM Produce our basic Space Invaders layout a la title sequence. CLS:PROCdraw_rail(rail%!toprail%):PROCdraw_rail(rail%!baserail%) PROCplot(FNsprite_get(100),space%!xpos%,space%!ypos%) PROCplot(FNsprite_get(101),invt%!xpos%,invt%!ypos%) REM Build and display the text. string$=FNstring_get(54)+" "+STR$(player%!score%) string$+=" "+FNstring_get(55)+" "+STR$(pos%)+FNsuffix(pos%) str%=LEN(string$)*screen%!xfont% x%=FNcentre_text(str%,screen%!xsize%):y%=invt%!ypos%-170 PROCprint(x%,y%,string$,0) REM Free memory used by objects. PROCash_free(space%):PROCash_free(invt%) REM Create and display a box... box%!xsize%=165:box%!ysize%=40 box%=FNcentre_sprite_xy(box%,screen%):PROCdraw_box(box%) REM Handle player input... REM Code 13 is Return/Enter. Code 8 is BackSpace. All other codes REM are filtered with FNvalid() before being added to string$ REM to prevent the program breaking when we can't find a graphic. x%=box%!xpos%+20:y%=box%!ypos%+12:string$="":i%=1:done%=FALSE OSCLI"FX 21,0" :REM Flush Keyboard buffer... REPEAT g%=GET :REM Get a char from Keyboard. REM Validate input... REM Only allow character input if our string length is less REM than 8 characters. Only accept Enter or Backspace for the REM 9th character. CASE g% OF WHEN 13 :done%=TRUE WHEN 8 :i%-=1:string$=LEFT$(string$,i%-1) OTHERWISE :IF i%<9 AND FNvalid(g%) THEN i%+=1:string$+=CHR$(g%) ENDCASE REM Update Display... REM Var i% will be less than 1 if the first character pressed REM was backspace. We need to trap that and make it 1. We also REM clear the input field before we re-display string$... This REM is so that when Backspace is pressed, the character is REM actually removed from the screen as well as from the input. REM (string$) REM We also need to check if we are trying to display an empty REM string, as our PROCprint() will fall over. This occurs if REM the first key typed was BackSpace or a character we can't REM display. (In the case of the latter, it is not added to REM string$, but we still come down here to update the display.) IF i%<1 THEN i%=1 PROCprint(x%,y%,STRING$(8," "),0) IF string$<>"" THEN PROCprint(x%,y%,string$,0) UNTIL done% REM Add player's name to entry already prepared earlier and save REM if we can... (scores_save%=TRUE) IF string$="" OR string$=" " THEN string$=FNstring_get(56) scores_name$(pos%)=FNencode_string(string$) IF gamestate%!scores_save% THEN PROChitable_save ENDPROC REM Have we got the ability to display this character? REM Return TRUE if we can or FALSE if we can't DEFFNvalid(chr%) LOCAL out% out%=FALSE IF chr%>=32 AND chr%<=126 THEN out%=TRUE =out% REM ************************************************************* REM Functions & Proceedures (HUD & Scoring) REM ************************************************************* REM Initialise the HUD display... DEFPROChud_init(sc%,hi%,l%,r%) LOCAL x%,string$ string$=FNstring_get(57)+" "+FNstring_get(59) string$+=FNstr_pad(STR$(sc%),10," ",TRUE) PROCprint(0,screen%!ysize%-screen%!yfont%,string$,0) string$=FNstring_get(58)+" "+FNstring_get(57) string$+=" "+FNstring_get(59)+FNstr_pad(STR$(hi%),10," ",TRUE) x%=screen%!xsize%-LEN(string$)*screen%!xfont% PROCprint(x%,screen%!ysize%-screen%!yfont%,string$,0) PROChud_lives(l%):PROChud_rack(r%):PROChud_soundstate ENDPROC REM Update HUD lives display... DEFPROChud_lives(num%) LOCAL string$ PROCplot(FNsprite_get(1),0,0):string$=" = "+STR$(num%) PROCprint(base%!xsize%,0,string$,0) ENDPROC REM Update HUD rack display... DEFPROChud_rack(num%) LOCAL x%,string$ string$=FNstring_get(60)+" "+FNstring_get(59) string$+=FNstr_pad(STR$(num%),3,"0",TRUE) x%=screen%!xsize%-LEN(string$)*screen%!xfont% PROCprint(x%,0,string$,0) ENDPROC REM HUD banner text display routine... REM This is called by the Pause Game & Extra Life event refresh REM handlers at the moment and possibly others in the future. DEFPROChud_bannertext(string$) LOCAL x%,y%,str% str%=LEN(string$)*screen%!xfont% x%=FNcentre_text(str%,screen%!xsize%) y%=screen%!ysize%-screen%!yfont% PROCprint(x%,y%,string$,0) ENDPROC REM Score a hit... REM The first part updates the score display on the top left REM corner of the HUD. If the player's current score is greater REM than that of the top spot, this value is also reflected in the REM Hi Score display in the top right. For every 5k points the REM player scores, he/she gains an extra base. We check this and REM increment here too. DEFPROChud_scorehit(value%) LOCAL elscore%,elcount%,x%,string$ elscore%=12:elcount%=16 :REM Object offsets. player%!score%+=value% string$=FNstring_get(57)+" "+FNstring_get(59) string$+=FNstr_pad(STR$(player%!score%),10," ",TRUE) PROCprint(0,screen%!ysize%-screen%!yfont%,string$,0) IF player%!score%-gamestate%!elscore%>=5000 THEN player%!lives%+=1:PROChud_lives(player%!lives%) gamestate%!elscore%=player%!score%:gamestate%!elcount%=0 ENDIF IF player%!score%>scores_value%(1) THEN string$=FNstring_get(58)+" "+FNstring_get(57)+" " string$+=FNstring_get(59) string$+=FNstr_pad(STR$(player%!score%),10," ",TRUE) x%=screen%!xsize%-LEN(string$)*screen%!xfont% PROCprint(x%,screen%!ysize%-screen%!yfont%,string$,0) ENDIF ENDPROC REM Display sound status... REM Displays one of three icons in the HUD area depending on the REM current sound status. The placement of this needs to make REM sense during both game and attract modes. DEFPROChud_soundstate LOCAL status%,snd%,fr$ snd%=FNash_claim(16) :REM Claim space for image block. status%=0 :REM Object offsets. (gamestate%) snd%!xsize%=FNconv_units(20,1):snd%!ysize%=FNconv_units(10,2) snd%!xpos%=FNcentre_sprite(snd%,screen%):snd%!ypos%=0 REM Trap invalid sound state. REM by the time this is called, our status flag should be setup REM to something meaningful. Just in case it isn't, we sanity REM check it here. IF gamestate%!status%<0 OR gamestate%!status%>2 THEN ERROR255,FNstring_get(111)+" "+STR$(gamestate%!status%) ENDIF REM Update display and free ASH block. fr$=FNsprite_get(120+gamestate%!status%) PROCplot(fr$,snd%!xpos%,snd%!ypos%):PROCash_free(snd%) ENDPROC REM ************************************************************* REM Functions & Proceedures (Rack & Invaders) REM ************************************************************* REM Cold initialisation... REM Called directly by PROCmain once at the beginning of each REM game to initialise the first wave... DEFPROCrack_gameinit LOCAL frame%,scol%,ecol%,rownum% frame%=flags1%:scol%=flags5%:ecol%=flags6%:rownum%=flags7% PROCrack_init:PROCrack_redraw ENDPROC REM Initialise a rack of invaders... REM This is called at the beginning of the game and whenever REM rack%!beenhit%=rack%!xnum%*rack%!ynum% (All invaders hit.) REM to produce the next wave of the invasion force... We hold the REM status of each invader in the invstat%() array... REM Value Significance REM ======================== REM -n Just been hit. REM 0 Dead and buried. REM >0 Current graphic. DEFPROCrack_init LOCAL col%,row%,s% REM Rack properties... REM These are set here as they have to be reset at the beginning REM of each wave. rack%!xpos%=50:rack%!ypos%=550:rack%!frame%=0:rack%!beenhit%=0 rack%!speed%=3:rack%!dir%=rack%!speed%:rack%!scol%=1 rack%!ecol%=rack%!xnum%:rack%!rownum%=1 REM Use s% as a temporary to avoid problems with line length in REM !Zap edit window. s%=(rack%!xnum%*inv%!xsize%)+((rack%!xnum%-1)*rack%!colgap%) rack%!xsize%=s%:rack%!ysize%=rack%!ynum%*inv%!ysize% REM Initialise invaders status. FOR row%=1 TO rack%!xnum% FOR col%=1 TO rack%!ynum% invstat%(row%,col%)=((col%+1)/2)+(rack%!frame%*10) NEXT col% NEXT row% ENDPROC REM Redraw the whole rack of invaders at once. DEFPROCrack_redraw LOCAL col%,row%,x%,y%,blk%:blk%=FNash_claim(16) FOR row%=rack%!scol% TO rack%!ecol% x%=rack%!xpos%+((row%-1)*(inv%!xsize%+rack%!colgap%)) FOR col%=rack%!rownum% TO rack%!ynum% y%=rack%!ypos%+((col%-1)*inv%!ysize%) IF invstat%(row%,col%)>0 THEN invstat%(row%,col%)=((col%+1)/2)+(rack%!frame%*10) ENDIF IF invstat%(row%,col%)<>0 THEN CASE SGN(invstat%(row%,col%)) OF WHEN -1 : PROCrack_checkinv(x%,y%,row%,col%) WHEN 1 : PROCplot(FNsprite_get(27)+STR$(invstat%(row%,col%)),x%,y%) ENDCASE ELSE blk%!xpos%=x%:blk%!ypos%=y%:blk%!xsize%=inv%!xsize% blk%!ysize%=inv%!ysize%:PROCwipe_sprite(blk%) ENDIF NEXT col% NEXT row% PROCash_free(blk%) ENDPROC REM We start our explosion at -5. Every time we redraw an invader REM we add to the count until zero is reached. When this happens REM we wipe the sprite by creating a temporary object and passing REM it to PROCwipe_sprite() in the normal way. REM +----+--------------------------+ REM | x% | Physical X co-ordinate. | REM | y% | Physical Y co-ordinate. | REM | r% | Row index into array. | REM | c% | Column index into array. | REM +----+--------------------------+ DEFPROCrack_checkinv(x%,y%,r%,c%) LOCAL blk% invstat%(r%,c%)+=1:PROCplot(FNsprite_get(26),x%,y%) IF invstat%(r%,c%)=0 THEN blk%=FNash_claim(16):blk%!xpos%=x%:blk%!ypos%=y% blk%!xsize%=inv%!xsize%:blk%!ysize%=inv%!ysize% PROCwipe_sprite(blk%):PROCash_free(blk%) ENDIF ENDPROC REM Advance rack down by one row... REM Object blk% hovers above the top row of invaders to allow me a REM quick use of PROCwipe_sprite() to remove the old top row. We REM drop a row by dropping 1/3 of a row three times to lessen the REM "jump". The original used to do something like this, but I'm REM guessing this was down to the lack of CPU power rather than by REM design. DEFPROCrack_advance LOCAL blk%,i%:blk%=FNash_claim(16) FOR i%=1 TO 3 rack%!ypos%-=inv%!ysize%/3:PROCrack_redraw NEXT i% blk%!xpos%=rack%!xpos% blk%!ypos%=rack%!ypos%+rack%!ysize% blk%!xsize%=rack%!xsize%:blk%!ysize%=inv%!ysize% PROCwipe_sprite(blk%):PROCash_free(blk%) ENDPROC REM End game... REM We are called when the rack of invaders has reached the REM player's base. Do a little animation before we return to the REM Hiscore entry etc... DEFPROCrack_endgame LOCAL inv_left%,inv_right%,mt%,frtime%,alt%,speed%,i%,img$ speed%=1:inv_ext%=24 REM Reserve space... inv_left%=FNash_claim(28):inv_right%=FNash_claim(28) REM Clear any in-game debris from the screen. (Invaders, saucers REM and other junk.) PROCwipe_sprite(rack%):PROCwipe_sprite(base%) IF shell%!active% THEN PROCwipe_sprite(shell%):shell%!active%=FALSE ENDIF IF saucer%!active% THEN PROCwipe_sprite(saucer%):saucer%!active%=FALSE ENDIF PROCinvfire_clearall:PROCbunk_clearall REM Setup initial values. base%!xpos%=FNcentre_sprite(base%,screen%) inv_left%!xpos%=0-inv%!xsize% :REM Left invader properties. inv_left%!ypos%=base%!ypos% inv_left%!dir%=speed% inv_right%!xpos%=screen%!xsize% :REM Right invader properties. inv_right%!ypos%=base%!ypos% inv_right%!dir%=0-speed% REM Zero any remaining lives & update bottom of HUD... player%!lives%=0:PROCdraw_rail(rail%!baserail%) PROChud_lives(player%!lives%):PROChud_rack(player%!racknum%) REM Hit it!! REM Two invaders, one from each side, approach the base and blow REM it up... PROCplot(FNsprite_get(1),base%!xpos%,base%!ypos%) REM The approach... frame%=0:alt%=FALSE REPEAT inv_left%!xpos%+=inv_left%!dir% inv_left%!inv_ext%=inv_left%!xpos%+inv%!xsize% inv_right%!xpos%+=inv_right%!dir% SYS FNswi_get(6) TO mt% :REM OS_ReadMonotonicTime IF mt%-frtime%>=50 THEN alt%=FNtoggle(alt%):frtime%=mt% IF alt% THEN img$=FNsprite_get(21) ELSE img$=FNsprite_get(20) PROCplot(img$,inv_left%!xpos%,inv_left%!ypos%) PROCplot(img$,inv_right%!xpos%,inv_right%!ypos%) PROCwait(2):WAIT UNTIL inv_left%!inv_ext%>=base%!xpos% REM The cheer... FOR i%=1 TO 10 PROCplot(FNsprite_get(20),inv_left%!xpos%,inv_left%!ypos%) PROCplot(FNsprite_get(20),inv_right%!xpos%,inv_right%!ypos%) PROCwait(20) PROCplot(FNsprite_get(21),inv_left%!xpos%,inv_left%!ypos%) PROCplot(FNsprite_get(21),inv_right%!xpos%,inv_right%!ypos%) PROCwait(20):WAIT NEXT i% REM The end... PROCsfx_play(2) FOR i%=1 TO 3 PROCplot(FNsprite_get(2)+STR$(i%),base%!xpos%,base%!ypos%) PROCwait(20):WAIT NEXT i% PROCwait(20):PROCwipe_sprite(base%) PROCash_free(inv_left%):PROCash_free(inv_right%) ENDPROC REM ************************************************************* REM Functions & Proceedures (Invader Fire) REM ************************************************************* REM Setup our array of invader missile objects... REM Like everything else, sizes are supplied in pixels. These are REM passed to FNconv_units() which converts them to OS Units. All REM system calls expect these values as OS Units. DEFPROCinvfire_init LOCAL i%,hittime%,frtime% hittime%=flags3%:frtime%=flags4% :REM Offsets. FOR i%=1 TO 10 invfire%(i%)=FNash_claimfilled(48,0) :REM Claim memory. invfire%(i%)!xsize%=FNconv_units(5,1) :REM Width (In px.) invfire%(i%)!ysize%=FNconv_units(20,2) :REM Height (In px.) SYS FNswi_get(6) TO invfire%(i%)!hittime% :REM Timer stores. SYS FNswi_get(6) TO invfire%(i%)!frtime% invfire%(i%)!active%=FALSE :REM Set inactive. NEXT i% ENDPROC REM If we haven't already got an active missile in this slot REM then we create one. The likelyhood of this happening is REM a percentage chance based on the player's current level +5. REM This is capped by a second call to FNpct(), the value of REM which is initially 4. This value is incremented by 1 for REM every 10 racks the player destroys. REM Prop.. | Value | Comments. REM -------+---------+-------------- REM type% | 1 or 2 | Missile type. (Type 1 can be hit.) REM frame% | 0,1,2,3 | Current frame. (2 & 3 For type 2 only.) REM Missile types are defined 75/25. Having a 75% chance of REM being type 1. Speed for type 1 is 4 OS Units per frame, for REM type 2, we half that. DEFPROCinvfire_create(slot%) LOCAL fpos%,firepos%,frate%,spd%,x%,y% LOCAL frame%,type% frame%=flags1%:type%=flags2% :REM Object properties. fpos%=RND(10):frate%=player%!racknum%+5 :REM Other constants. IF frate%>100 THEN frate%=100 IF player%!racknum% MOD 10=0 THEN rack%!frcap%+=1 ENDIF IF FNpct(frate%) AND FNpct(rack%!frcap%) THEN IF invstat%(fpos%,rack%!rownum%)>0 THEN x%=rack%!xpos%+(fpos%-1)*(inv%!xsize%+rack%!colgap%) y%=rack%!ypos%+((rack%!rownum%-1)*inv%!ysize%)-inv%!ysize% firepos%=(inv%!xsize%/2)-(invfire%(slot%)!xsize%/2) invfire%(slot%)!xpos%=x%+firepos% invfire%(slot%)!ypos%=y% invfire%(slot%)!active%=TRUE:invfire%(slot%)!beenhit%=FALSE invfire%(slot%)!type%=1:invfire%(slot%)!frame%=0:spd%=4 IF FNpct(25) THEN invfire%(slot%)!type%=2:spd%=spd%/2 invfire%(slot%)!speed%=spd% invfire%(slot%)!dir%=invfire%(slot%)!speed% PROCsfx_play(3) ENDIF ENDIF ENDPROC REM Continue animating down the screen... REM Handle the image swapping (for the animation) and the REM position of the currently selected invader missile. DEFPROCinvfire_animate(slot%) LOCAL mt%,frame%,frtime%,type%,fr$,fr2$ REM Assign meaningful names to object specific flags. frame%=flags1%:type%=flags2%:frtime%=flags4% SYS FNswi_get(6) TO mt% :REM Handle the timer... IF mt%-invfire%(slot%)!frtime%>=40 THEN invfire%(slot%)!frtime%=mt% invfire%(slot%)!frame%+=1 ENDIF :REM Limit frame counter... IF invfire%(slot%)!type%=1 AND invfire%(slot%)!frame%>1 THEN invfire%(i%)!frame%=0 ENDIF IF invfire%(slot%)!type%=2 AND invfire%(slot%)!frame%>3 THEN invfire%(slot%)!frame%=0 ENDIF fr2$=STR$(invfire%(slot%)!frame%) :REM Prepare frame... IF invfire%(slot%)!type%=2 AND invfire%(slot%)!frame%=3 THEN fr2$="1" ENDIF fr$=FNsprite_get(30)+STR$(invfire%(slot%)!type%)+fr2$ REM Display frame... REM Only advance and display prepared frame if we haven't REM already been hit, otherwise we just display the explosion. IF NOT invfire%(slot%)!beenhit% THEN invfire%(slot%)!ypos%-=invfire%(slot%)!dir% PROCplot(fr$,invfire%(slot%)!xpos%,invfire%(slot%)!ypos%) ELSE fr$=FNsprite_get(30)+"3" PROCplot(fr$,invfire%(slot%)!xpos%,invfire%(slot%)!ypos%) ENDIF ENDPROC REM Missile has hit the player's base... DEFPROCinvfire_hitbase(slot%) LOCAL i% PROCsfx_play(2) FOR i%=1 TO 3 PROCplot(FNsprite_get(2)+STR$(i%),base%!xpos%,base%!ypos%) PROCwait(20):WAIT NEXT i% PROCwipe_sprite(base%) IF shell%!active% THEN PROCwipe_sprite(shell%):shell%!active%=FALSE ENDIF base%!xpos%=FNcentre_sprite(base%,screen%) player%!lives%-=1:PROChud_lives(player%!lives%) PROCwipe_sprite(invfire%(slot%)):invfire%(slot%)!active%=FALSE PROCplot(FNsprite_get(1),base%!xpos%,base%!ypos%) ENDPROC REM We've been hit by a player's shell... DEFPROCinvfire_beenhit(slot%) LOCAL type%,hittime% type%=flags2%:hittime%=flags3% :REM Object offsets. IF invfire%(slot%)!type%=1 THEN IF NOT invfire%(slot%)!beenhit% THEN invfire%(slot%)!beenhit%=TRUE:PROChud_scorehit(5) fr$=FNsprite_get(30)+"3" PROCplot(fr$,invfire%(slot%)!xpos%,invfire%(slot%)!ypos%) SYS FNswi_get(6) TO invfire%(slot%)!hittime% ENDIF ENDIF PROCwipe_sprite(shell%):shell%!active%=FALSE ENDPROC REM We have been destroyed... DEFPROCinvfire_explode(slot%) LOCAL hittime%,mt% hittime%=flags3% :REM Object offsets. SYS FNswi_get(6) TO mt% IF mt%-invfire%(slot%)!hittime%>=40 THEN PROCwipe_sprite(invfire%(slot%)) invfire%(slot%)!active%=FALSE ENDIF ENDPROC REM Clear all invader missiles off the screen... REM Used by PROCrack_endgame in preparation for the animation. DEFPROCinvfire_clearall LOCAL i%,items%:items%=52 FOR i%=1 TO gamestate%!items% IF invfire%(i%)!active% THEN PROCwipe_sprite(invfire%(i%)):invfire%(i%)!active%=FALSE ENDIF NEXT i% ENDPROC REM ************************************************************* REM Functions & Proceedures (Bunkers) REM ************************************************************* REM Setup an arbitary number of bunkers... REM This allocates memory and performs the calculations required REM to convert from pixels to OS Units to give us the correct REM sizes for all further display & collision detection etc... REM Bunker positions are calculated using the following formula... REM x=(s/n)+((c-1)*(s/n)) -> Gives us the position of the current REM bunker. Where x = X Co-ordinate. REM s = Screen width. REM n = Number of bunkers. REM c = Current bunker. DEFPROCbunk_init LOCAL i%,x%,gap%,hitcount%,num% num%=gamestate%!56 :REM Number of bunkers. hitcount%=flags1% :REM Object offsets. gap%=screen%!xsize%/num% :REM Gap between bunkers. x%=gap%-150 :REM Left bunker pos. FOR i%=1 TO num% bunker%(i%)=FNash_claimfilled(48,0) :REM Claim memory. bunker%(i%)!xsize%=FNconv_units(30,1) :REM Width (In px.) bunker%(i%)!ysize%=FNconv_units(15,2) :REM Height (In px.) bunker%(i%)!xpos%=x%+((i%-1)*gap%) :REM Position (X) bunker%(i%)!ypos%=base%!ypos%+100 :REM Position (Y) bunker%(i%)!active%=TRUE :REM Set active. bunker%(i%)!hitcount%=0 :REM Hit counter. NEXT i% ENDPROC REM Reset all bunkers to active state... REM Perform a quick init. We already know where everything goes, REM we just need to get them all in a known condition. DEFPROCbunk_reset LOCAL i%,hitcount%,num% num%=gamestate%!56 :REM Number of bunkers. hitcount%=flags1% :REM Object offsets. FOR i%=1 TO num% bunker%(i%)!active%=TRUE :REM Set active. bunker%(i%)!hitcount%=0 :REM Reset hit counter. NEXT i% ENDPROC REM Redraw all active bunkers... REM Does much the same as PROCbunk_init, but without all the setup REM as we already know where everything is. DEFPROCbunk_redraw LOCAL i%,num% num%=gamestate%!56 :REM Number of bunkers. FOR i%=1 TO num% IF bunker%(i%)!active% THEN PROCplot(FNsprite_get(16),bunker%(i%)!xpos%,bunker%(i%)!ypos%) ENDIF NEXT i% ENDPROC REM Bunker collision detection... REM Both invader fire and player fire handlers call this routine REM if they detect a collision with a bunker. Bunkers can be hit REM 10 times by either invader fire or player's shots before they REM disappear until the beginning of the next rack. Var by% is REM TRUE if hit by player or FALSE otherwise. DEFPROCbunk_beenhit(slot%,by%) LOCAL y%,hitcount% hitcount%=flags1%:timer%=flags2% :REM Object offsets. bunker%(slot%)!hitcount%+=1 :REM Increment hit counter. IF bunker%(slot%)!hitcount%>=10 THEN PROCwipe_sprite(bunker%(slot%)):bunker%(slot%)!active%=FALSE ELSE y%=bunker%(slot%)!ypos% IF by% THEN y%+=5 ELSE y%-=5 :REM Move up or down on hit. PROCwipe_sprite(bunker%(slot%)) PROCplot(FNsprite_get(16),bunker%(slot%)!xpos%,y%) bunker%(slot%)!beenhit%=TRUE SYSFNswi_get(6) TO bunker%(slot%)!timer% ENDIF ENDPROC REM Clear all bunkers off the screen... REM Used by PROCrack_endgame in preparation for the animation. DEFPROCbunk_clearall LOCAL i%,blk%,num% num%=gamestate%!56 FOR i%=1 TO num%:bunker%(i%)!active%=FALSE:NEXT i% blk%=FNash_claim(16):blk%!xpos%=0:blk%!ypos%=bunker%(1)!xpos% blk%!xsize%=screen%!xsize%:blk%!ysize%=bunker%(1)!ysize% PROCwipe_sprite(blk%):PROCash_free(blk%) ENDPROC REM ************************************************************* REM Functions & Proceedures (Core Graphics Routines) REM ************************************************************* REM Load a gfx file... REM Doing it this way allows us to use two different buffers, one REM for the sprites and the other for the charset. DEFFNgfx_load(filespec$) LOCAL area%,size% size%=FNfs_filesize(filespec$)+256 :REM Find filesize. area%=FNash_claim(size%) :REM Reserve space. !area%=size%:area%!4=0:area%!8=16:area%!12=16 :REM Set pointers. REM Load Graphics into our reserved space... SYS gfx_spriteop%, 256+10, area%, filespec$ :REM Load file. SYS gfx_spriteop%, 256+17, area% :REM Verify data. =area% REM Display a string character by character with a delay between REM each one. Each character is indexed to the 8*8 character set REM sprites using ASCII codes. DEFPROCprint(x%,y%,string$,char_delay%) LOCAL i%,chsize% gfx_area%=gfx_fontpool% :REM Switch to our charset. chsize%=screen%!xfont% FOR i%=1 TO LEN(string$) PROCplot(STR$(ASC(MID$(string$,i%,1))),x%+((i%-1)*chsize%),y%) IF char_delay%>0 THEN PROCwait(char_delay%) NEXT i% gfx_area%=gfx_spritepool% :REM Switch back... ENDPROC REM Display a given image. Modified to use a local sprite area & REM system calls to speed things up dramatically. (02/01/08) REM sprite$ = Name of image to display. REM x% = X Co-ordinate. REM y% = Y Co-ordinate. DEFPROCplot(sprite$,x%,y%) LOCAL address% SYS gfx_spriteop%, 256+24, gfx_area%, sprite$ TO ,, address% SYS gfx_spriteop%, 512+34, gfx_area%, address%, x%, y%, 0 ENDPROC REM Clear a sprite from the screen. (New method.) REM Before we created an identical bitmap in the sprite file REM and displayed this over our image. This should be faster, and REM result in a smaller sprite file. DEFPROCwipe_sprite(obj%) GCOL0,0 TINT0 RECTANGLE FILLobj%!xpos%,obj%!ypos%,obj%!xsize%,obj%!ysize% ENDPROC REM ************************************************************* REM Functions & Proceedures (Text & Graphics Alignment.) REM ************************************************************* REM Centre text horizontally... REM Where string_length% is the length of the string in multiples REM of OS Units, where each multiple is the width of a character. REM Var screen% is the screen width. REM width... DEFFNcentre_text(string_length%,screen%) =(screen%/2)-(string_length%/2) REM Centre text horizontally & vertically. DEFPROCcentre_text_xy(string$,delay%) LOCAL str%,y% str%=LEN(string$)*screen%!xfont% y%=(screen%!ysize%/2)-(screen%!yfont%/2) PROCprint(FNcentre_text(str%,screen%!xsize%),y%,string$,delay%) ENDPROC REM Centre sprite horizontally... REM Takes the two "object" blocks as parameters and extracts the REM required values from them. Then returns the centre position. DEFFNcentre_sprite(object%,relative%) =(relative%!xsize%/2)-(object%!xsize%/2) REM Centre sprite horizontally & vertically. REM Returns the new position at offsets xpos% & ypos% in object%. DEFFNcentre_sprite_xy(object%,relative%) LOCAL x%,y% object%!xpos%=(relative%!xsize%/2)-(object%!xsize%/2) object%!ypos%=(relative%!ysize%/2)-(object%!ysize%/2) =object% REM ************************************************************* REM Functions & Proceedures (Graphical Boxes & Lines.) REM ************************************************************* REM Repeat a 6*6 image across the screen to produce a "rail" like REM effect at position y%. DEFPROCdraw_rail(ypos%) LOCAL i%,reps% reps%=screen%!xsize%/rail%!xsize% FOR i%=1 TO reps%+1 PROCplot(FNsprite_get(108),(i%-1)*rail%!xsize%,ypos%) NEXT i% ENDPROC REM Produce a box to surround text in GAME OVER!!! & GOODBYE!!! REM texts. (Among others.) DEFPROCdraw_box(obj%) LOCAL x%,y%,cxsize%,cysize%,rxsize%,rysize%,i% REM Setup... cxsize%=FNconv_units(3,1):cysize%=FNconv_units(3,2) rxsize%=1:rysize%=3 REM The top & bottom... FOR i%=1 TO obj%!xsize% x%=obj%!xpos%+((i%-1)*rxsize%) PROCplot(FNsprite_get(113),x%,obj%!ypos%) PROCplot(FNsprite_get(113),x%,obj%!ypos%+(obj%!ysize%-(2*rysize%))) NEXT i% REM The two sides... x%=obj%!xpos%+(obj%!xsize%-cxsize%) FOR i%=1 TO obj%!ysize%-1 PROCplot(FNsprite_get(114),obj%!xpos%,obj%!ypos%+((i%-1)*rxsize%)) PROCplot(FNsprite_get(114),x%,obj%!ypos%+((i%-1)*rxsize%)) NEXT i% REM The four corners... PROCplot(FNsprite_get(111),obj%!xpos%,obj%!ypos%) PROCplot(FNsprite_get(109),obj%!xpos%,(obj%!ypos%+obj%!ysize%)-cysize%) PROCplot(FNsprite_get(112),obj%!xpos%+(obj%!xsize%-cxsize%),obj%!ypos%) x%=(obj%!xpos%+obj%!xsize%)-cxsize% y%=(obj%!ypos%+obj%!ysize%)-cysize% PROCplot(FNsprite_get(110),x%,y%) ENDPROC REM ************************************************************* REM Functions & Proceedures (String & Text De-coding) REM ************************************************************* REM These routines deal with our garbled strings. This is done REM this way for a couple of reasons... REM # BasCrunch output is smaller. REM # BasCrunch ouptut is harder to reverse engineer. REM Get number of messages in a processed file... DEFFNstring_enumprocessed(filespec$,magic$) LOCAL in_hdl%,count%,maggot$ in_hdl%=OPENIN(filespec$) INPUT#in_hdl%,maggot$ IF maggot$<>magic$ THEN CLOSE#in_hdl%:ERROR 255,"Bad Magic!" INPUT#in_hdl%,count% CLOSE#in_hdl% =count% REM Load a file off disc and return messages setup in arrays. DEFPROCstring_load(filespec$,magic$,RETURN nums%(),RETURN strs$()) LOCAL in_hdl%,i%,count%,maggot$ in_hdl%=OPENIN(filespec$) INPUT#in_hdl%,maggot$ IF maggot$<>magic$ THEN CLOSE#in_hdl%:ERROR 255,"Bad Magic!" INPUT#in_hdl%,count% FOR i%=1 TO count% INPUT#in_hdl%,nums%(i%),strs$(i%) NEXT i% CLOSE#in_hdl% ENDPROC REM The following functions are all identical, other than what is REM actually searched. (The arrays are different.) So... To avoid REM duplicating code, I've written a generic search routine with REM three wrappers passing the correct values to the generic code. REM Retrieve an encoded message for display... (Wrapper...) DEFFNstring_get(msg%) =FNcore_get(msg%,string_max%,string_num%(),string_msg$(),106) REM Retrieve an encoded Sprite name... (Wrapper...) DEFFNsprite_get(msg%) =FNcore_get(msg%,ilut_max%,ilut_num%(),ilut_msg$(),107) REM Retrieve an encoded SWI name... (Wrapper...) DEFFNswi_get(msg%) =FNcore_get(msg%,slut_max%,slut_num%(),slut_msg$(),108) REM Generic core code for above get functions... DEFFNcore_get(msg%,max%,num%(),str$(),msg_err%) LOCAL i%,found%:found%=0 FOR i%=1 TO max% IF num%(i%)=msg% THEN found%=i%:i%=max% NEXT i% IF found%=0 THEN IF msg%>=106 AND msg%<=108 THEN ERROR 255,"Missing message!!!" ELSE ERROR 255,FNstring_get(msg_err%)+" "+STR$(msg%) ENDIF ENDIF =FNencode_string(str$(found%)) REM ************************************************************* REM Functions & Proceedures (Sound Sub-system OS call wrappers.) REM ************************************************************* REM Load a song into memory and return a handle... DEFFNtp_loadsong(filespec$) LOCAL hdl%:hdl%=0 SYSFNswi_get(31),,filespec$ TO hdl% =hdl% REM Trigger one of a number of loaded sound effects... REM The number passed in what% is the number of the sample to REM play. We currently only have 4 sound effects numbered 1-4. DEFPROCsfx_play(what%) LOCAL status%,err$ status%=0:err$=FNstring_get(110)+" "+STR$(what%) IF gamestate%!status%>0 THEN IF what%<1 AND what%>4 THEN ERROR255,err$ OSCLI"SPlay_fire0"+STR$(what%)+"mhh" ENDIF ENDPROC REM ************************************************************* REM Functions & Proceedures (Misc. Game Specific.) REM ************************************************************* REM Get various information about screen resolution. This includes REM viewing area and conversion factors. We cannot rely on fixed REM values because they change from mode to mode. So grab the REM current values from the OS and bung 'em into some variables. DEFPROCget_screeninfo LOCAL blk% blk%=FNash_claim(20) :REM Reserve space for parameter block. REM Setup parameter block... blk%!0=4 :REM XEigFactor (Convert.) blk%!4=5 :REM YEigFactor (Convert.) blk%!8=11 :REM XWindLimit (Width.) blk%!12=12 :REM YWindLimit (Height.) blk%!16=-1 :REM Termination byte. SYS FNswi_get(5), blk%, blk%:REM Call OS. REM Setup our screen% object... screen%!x_eig%=blk%!0 :REM X & Y EigFactor. screen%!y_eig%=blk%!4 screen%!xsize%=(blk%!8)+1< OS Units) REM 2 = Height (Pixels > OS Units) REM 3 = Width (OS Units > Pixels) REM 4 = Height (OS Units > Pixels) REM Returns REM conv% = Converted value. DEFFNconv_units(size%,op%) LOCAL conv%,mode% REM Check to see if the screen mode has changed. If so, then REM call PROCget_screeninfo to update the values. This is REM probably overkill and can be omitted, but still good practice REM for debugging. mode%=MODE IF mode%<>screen%!setmode% THEN PROCget_screeninfo REM Do the conversion. CASE op% OF WHEN 1 : conv%=size%<>screen%!x_eig% WHEN 4 : conv%=size%>>screen%!y_eig% OTHERWISE ERROR 255,FNstring_get(103)+" "+STR$(op%) ENDCASE =conv% REM Collision detection. Takes two objects and returns TRUE if REM one is inside or has hit the other, else returns FALSE. Vars REM tx_ext% & ty_ext% hold the two far edges of the sprite. We REM calculate these by adding the target object's size to it's REM position each time we're called. We then use these values to REM perform a bounds check, one for x (ix% is TRUE if in.) and REM one for y (iy% is TRUE if in.). Finally... We return an REM evaluation of ix% AND iy%. DEFFNhit(obj%,targ%) LOCAL tx_ext%,ty_ext%,ix%,iy% ix%=FALSE:iy%=FALSE IF obj%!active% AND targ%!active% THEN tx_ext%=targ%!xpos%+targ%!xsize% :REM Right hand edge. ty_ext%=targ%!ypos%+targ%!ysize% :REM Top edge. IF obj%!xpos%>=targ%!xpos% AND obj%!xpos%=targ%!ypos% AND obj%!ypos%-1 THEN SYS"TimPlayer_SongStop",gamestate%!4 SYS"TimPlayer_SongUnload",gamestate%!4 ENDIF REM Tear down ASH Sub-system. PROCash_destroy ENDPROC REM Display file info as we go... (Initialisation.) DEFFNfind(fspec$,msg$) LOCAL disp$,rc%,found%:found%=FALSE disp$=STRING$(10," "):RIGHT$(disp$,3)=" : " LEFT$(disp$,LEN(msg$))=msg$:rc%=FNfs_find(fspec$) IF rc%=1 THEN disp$+="OK.":found%=TRUE ELSE disp$+="Missing!!" ENDIF PRINTdisp$ =found% REM Run through a counter checking names of files in the "Screens" REM directory inside the application until we have a file not REM found condition. Set the counter to this. This routine starts REM from count% and stops at the first gap in a chain. REM Because we fire it from PROCevnt_kb_screendump we effectively REM handle any possible breakage in a chain of existing numbers REM because it'll always find the next free slot. We continue to REM count up until "Dump" and the number of digits in our count REM exceed the ADFS file name limit (10 Chars.), at that point we REM flag up an error by returning -1. This gives us a max count REM of 999999. Chances are we'd exceed the max number of files REM allowed in a directory before we'd ever hit this limit!! DEFFNinit_setdumpcounter(count%) LOCAL dump_name$,loc$ loc$=".Screens.":dump_name$="Dump"+STR$(count%) IF FNfs_find(loc$+dump_name$)<>0 THEN REPEAT count%+=1 dump_name$="Dump"+STR$(count%) UNTIL FNfs_find(loc$+dump_name$)=0 OR LEN(dump_name$)>10 IF LEN(dump_name$)>10 THEN count%=-1 ENDIF =count% REM ************************************************************* REM Functions & Proceedures (Generic & Portable Code) REM ************************************************************* REM Returns TRUE n% percent of the time... REM This is used all over the place, usually dictating the chances REM of a particular event occuring, or as a bias for properties. DEFFNpct(n%) LOCAL rnd% rnd%=RND(100) =rnd%<=n% REM Encode or decode a string using a simple XOR algo... This REM prevents hackers from peeking at and modifying strings in REM files. Strings are in reverse order in BASIC datafiles, but REM are still in plaintext format. REM string$ = String to mash up. REM Returns REM mashed$ = Mashed up string. DEFFNencode_string(string$) LOCAL i%,mashed$ FOR i%=1 TO LEN(string$) mashed$+=CHR$(ASC(MID$(string$,i%,1)) EOR 131) NEXT i% =mashed$ REM Introduce a delay of n% hundredths of a second. DEFPROCwait(n%) LOCAL t% t%=TIME+n% REPEAT:UNTIL TIME>=t% ENDPROC REM Toggle a flag between 0 & 1. DEFFNtoggle(n%) =n% EOR 1 REM Returns a suffix (st, nd, rd etc...) when given a number. This REM number can be any number of digits long, we just deal with the REM last digit. DEFFNsuffix(n%) LOCAL out$,u% u%=VAL(RIGHT$(STR$(n%),1)) out$=FNstring_get(65) IF u%>=1 AND u%<=3 THEN out$=FNstring_get(u%+61) =out$ REM ************************************************************ REM Functions & Proceedures (LibSTR) REM ************************************************************ REM I've imported the following two routines from my string utils REM library. Normally I'd just include them using the LIBRARY REM command, but that would kill the cruncher, so I've dumped them REM here... REM Pad a string to len% characters by adding multiple copies of REM char$ to it. If start% is set TRUE then we will add padding to REM the start of the string, else we add it at the end. If longer REM than len% characters, then chop it to len% characters. DEFFNstr_pad(string$,len%,char$,start%) LOCAL diff%,out$ diff%=len%-LEN(string$) :REM How many to add. IF diff%<=0 THEN out$=LEFT$(string$,len%) ELSE IF start% THEN out$=STRING$(len%,char$):RIGHT$(out$,LEN(string$))=string$ ELSE out$=string$+STRING$(diff%,char$) ENDIF ENDIF =out$ REM Fix a string's length to len% characters and return it right REM aligned... DEFFNstr_rightalign(string$,len%) LOCAL out$ out$=STRING$(len%," ") RIGHT$(out$,LEN(string$))=string$ =out$ REM ************************************************************ REM Functions & Proceedures (LibFS) REM ************************************************************ REM I've imported the following two routines from my fs utils REM library. Normally I'd just include them using the LIBRARY REM command, but that would kill the cruncher, so I've dumped them REM here... REM Check for the prescence of a filing system object at a given REM location. I say object, as this can check for the existance of REM directories as well as files. REM Parameter block... REM file$ = Filespec to check for in current directory. REM ...On Exit. REM found% = 0 Object not found. REM = 1 Object is a file. REM = 2 Object is a directory. DEFFNfs_find(file$) LOCAL found% SYS"XOS_File",17,file$ TO found% =found% REM Return the size of a file. (In bytes.) DEFFNfs_filesize(file$) LOCAL size% SYS FNswi_get(3),5,file$ TO ,,,,size% =size% REM Can we write to this file? Return TRUE or FALSE... REM I really need to find a better way of doing this. The logic is REM screwy and doesn't pick up on a write protected floppy. I'm REM not sure if this is down to this part of the check, or the REM logic further up which deals with the result from this code. REM op%=0 -> File doesn't exist. Var file$ contains location. REM op%=1 -> File exists. Can we write/replace it? DEFFNfs_writeable(op%,file$) LOCAL hdl%,flg%,flags%,result% result%=FALSE REM Attempt to open or create a file depending on our opcode. CASE op% OF WHEN 0 : hdl%=OPENUP(file$+"chkfile") WHEN 1 : hdl%=OPENUP(file$) OTHERWISE : ERROR 255,FNstring_get(104)+" "+STR$(op%) ENDCASE REM If we get this far and we still haven't got a valid file REM handle then it's fairly safe to say that we're never gonna REM get one, so skip the next bit and return FALSE. IF hdl%<>0 THEN SYS FNswi_get(4),254,hdl% TO flags%;flg% IF (flg% AND 1) THEN CLOSE#hdl%:ERROR 255,FNstring_get(105) IF ((flags% AND (1<<7))<>0) THEN result%=TRUE CLOSE#hdl% ENDIF =result% REM ************************************************************ REM Functions & Proceedures (Ash Heap manager for BASIC) REM Copyright (c)2004 7th Software. REM ************************************************************ REM Initialise ASH Subsystem... DEFPROCash_init LOCAL err% ash_heap%=0:ash_total%=0 SYS FNswi_get(10), -1, -1 TO ash_slot% SYS FNswi_get(11) TO ash_page% ; err% IF err% AND 1 THEN ash_page%=16384 PROCash_create(ash_page%) ENDPROC REM Release the memory used for our heap DEFPROCash_destroy IF ash_heap% THEN SYS FNswi_get(10), ash_heap%-&8000,-1 TO ash_slot% ash_heap%=0:ash_total%=0 ENDIF ENDPROC REM Claim a block from the heap - generate an error if claim fails REM Our block's size is now the requested size + 3 extra locations REM @ 4 bytes per location + 3 extra bytes. REM Offs | Significance. REM --------+--------------- REM 0 | Low guard-word. REM 4 | Block user area size in bytes. REM 8 | User area base address. (This is what is returned.) REM | High guard-word. DEFFNash_claim(bytes%) LOCAL block%,size% size%=(bytes%+15) AND &FFFFFFFC block%=FNash_alloc(size%) IF block% ELSE ERROR 254,FNstring_get(211) block%!0=&DEADDEAD :REM Store low guard-word... block%!4=bytes% :REM Store user area size... !(block%-8+(block%!-4))=&DEADDEAD :REM Store high guard-word... =block%+8 REM Claim a block of memory, as above, but fill it with a REM specified value before returning. DEFFNash_claimfilled(bytes%,value%) LOCAL block% block%=FNash_claim(bytes%) :REM Claim requested space... PROCash_blockfill(block%,value%) :REM Fill with spec'd value... =block% REM Free a block into the heap DEFPROCash_free(RETURN block%) IF FNash_blockchecklow(block%) THEN ERROR 254,FNstring_get(212) IF FNash_blockcheckhigh(block%) THEN ERROR 254,FNstring_get(213) block%-=8:ash_total%-=block%!-4 SYS FNswi_get(12), 3, ash_heap%, block% block% = 0 ENDPROC REM Return the size (in bytes) of a specified block. DEFFNash_blocksize(block%) LOCAL blk% blk%=block%-4 =blk%!0 REM Fill a block of memory with a specified value... DEFPROCash_blockfill(block%,value%) LOCAL offset%,size% size%=FNash_blocksize(block%) FOR offset%=0 TO size%-4 STEP 4 block%!offset%=value% NEXT offset% ENDPROC REM Create a block with identical contents to the original. DEFFNash_blockcopy(block%) LOCAL copy%,offset%,size% size%=FNash_blocksize(block%) copy%=FNash_claim(size%) FOR offset%=0 TO size%-4 STEP 4 copy%!offset%=block%!offset% NEXT offset% =copy% REM Returns TRUE if the low guardword has been garbaged. DEFFNash_blockchecklow(block%) block%-=8 IF block%!0<>&DEADDEAD THEN =TRUE =FALSE REM Returns TRUE if the high guardword has been garbaged. DEFFNash_blockcheckhigh(block%) block%-=8 IF !(block%-8+(block%!-4))<>&DEADDEAD THEN =TRUE =FALSE REM *** LibASH Internals *** REM Create a heap in the memory above HIMEM DEFPROCash_create(size%) IF ash_heap% THEN ERROR 254,FNstring_get(215) size%=(size%+ash_page%-1) AND NOT (ash_page%-1) ash_heap%=HIMEM SYS FNswi_get(10), ash_slot% + size%, -1 TO ash_slot% size%=ash_slot%+&8000-ash_heap% IF size%<1 THEN ash_heap%=0 ERROR 254,FNstring_get(216) ELSE SYS FNswi_get(12), 0, ash_heap%,, size% ENDIF ash_total%=0 ENDPROC REM Attempt to add some more memory into the end of our heap DEFPROCash_grow(bytes%) LOCAL prev% prev%=ash_slot% SYS FNswi_get(10), ash_slot%+bytes%, -1 TO ash_slot% bytes%=ash_slot%-prev% IF bytes% THEN SYS FNswi_get(12),5,ash_heap%,,bytes% TO ,,,bytes% ENDPROC REM Claim a block from the heap (grow it if need be) - return REM zero if claim fails. DEFFNash_alloc(bytes%) LOCAL block%, err% SYS FNswi_get(13), 2, ash_heap%,, bytes% TO ,, block% ; err% IF err% AND 1 THEN PROCash_grow((bytes%+ash_page%) AND NOT (ash_page%-1)) SYS FNswi_get(13), 2, ash_heap%,, bytes% TO ,, block% ; err% IF err% AND 1 THEN =0 ENDIF ash_total% += block%!-4 =block%