; This is a demo for the PPCASMPK PowerPC-emulator ; It requires at least Kickstart3.0 and AGA(or gfxboard) ; ; ;NOTE: This demo does not use absolute addressings like "ba". ; Yet, this would be possible without relocating the code ; because the emulator simulates the first instruction to ; reside at address 0. So if you jump to the correct offset, ; you can use "ba" or address local data without referring to ; a known "base-address" like is done here. ; ;----------------------------------------------------------------------------- cpu mpc601 ;----------------------------------------------------------------------------- ;AS 1.41r4 assembles code for BigEndian-mode,yet data-declarations ;are done LittleEndian or sometimes completely wrong.So this demo ;uses immediate-value instructions instead ; ;another bug of that assembler: the "spr" field at mtspr/mfspr instructions ;is supposed to be a split field in assemblers,where the value you specify ;in the source is split into 2 5bit-halves and these are swapped...at AS ;they are not swapped! ASBUGS equ 1 ;remove define if bug-free assembler is used ;;;;BO-field at conditional branches BO_true equ 12 ;if bit=1 BO_false equ 4 ;if bit=0 BO_always equ 0b10100 ;unconditional ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;;;;L-Bit at compare-instructions L_32bit equ 0 L_64bit equ 1 ;(64bit-PPCs only) ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;;;;spr-field at mtspr/mfspr ifdef ASBUGS SPR_XER equ 0x20 SPR_LR equ 0x100 SPR_CTR equ 0x120 endif ifndef ASBUGS SPR_XER equ 1 SPR_LR equ 8 SPR_CTR equ 9 endif ;;;;;;;;;;;;;;;;;;;;;;;;;;;; crf_lt equ 0 crf_gt equ 1 crf_eq equ 2 crf_so equ 3 ;;;;condition-register fields;;;; CR0 equ 0 CR1 equ 1 CR2 equ 2 CR3 equ 3 CR4 equ 4 CR5 equ 5 CR6 equ 6 CR7 equ 7 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;----------------------------------------------------------------------------- INCLUDE intui.lvo INCLUDE exec.lvo INCLUDE graphics.lvo INCLUDE input.lvo ;----------------------------------------------------------------------------- MYSCREEN_WIDTH equ 320 MYSCREEN_HEIGHT equ 200 MYSCREEN_DEPTH equ 8 MYSCREEN_BARHEIGHT equ 11 ;----------------------------------------------------------------------------- ;*** (STARTUP:) ;*** stack: r31 ;*** return address: LR ;*** execbase(mapped): r0 ;*** ;*** (INTERNAL:) ;*** base-address: r15 StartAdr: mfspr r1,SPR_LR ;save LR to r1 bl BaseAdr ;get the base-adr to LR BaseAdr: ;local memory is addressed relative to this address mfspr r15,SPR_LR ;r15=base-adr stw r1,MainReturnAdr-BaseAdr(r15) ;store the return-adr stw r0,ExecBase-BaseAdr(r15) ;store the execbase ;"intuition.library",0 addi r24,r15,IntuitionName-BaseAdr-1 addi r16,r0,'i' stbu r16,1(r24) addi r16,r0,'n' stbu r16,1(r24) addi r16,r0,'t' stbu r16,1(r24) addi r16,r0,'u' stbu r16,1(r24) addi r16,r0,'i' stbu r16,1(r24) addi r16,r0,'t' stbu r16,1(r24) addi r16,r0,'i' stbu r16,1(r24) addi r16,r0,'o' stbu r16,1(r24) addi r16,r0,'n' stbu r16,1(r24) addi r16,r0,'.' stbu r16,1(r24) addi r16,r0,'l' stbu r16,1(r24) addi r16,r0,'i' stbu r16,1(r24) addi r16,r0,'b' stbu r16,1(r24) addi r16,r0,'r' stbu r16,1(r24) addi r16,r0,'a' stbu r16,1(r24) addi r16,r0,'r' stbu r16,1(r24) addi r16,r0,'y' stbu r16,1(r24) addi r16,r0,0 stbu r16,1(r24) ;library = OpenLibrary(libName, version) ;d0 a1 d0 ;--------------------------------------- addi r16,r0,0 ;r0|0 ;d0 addi r25,r15,IntuitionName-BaseAdr;a1 addi r0,r0,( 1<<(31-25) )|2 ;input-mask: map a1&a6 addi r1,r0,1<<(31-16) ;output-mask: map d0 rlwinm r1,r1,0,16,31 ;clear the upper halveword lwz r30,ExecBase-BaseAdr(r15) lwz r2,_LVOOpenLibrary+2(r30) sc ;call it cmpi CR0,L_32bit,r16,0 bc BO_true,crf_eq,ERROR_NoIntuition stw r16,IntuitionBase-BaseAdr(r15) ;"graphics.library",0 addi r24,r15,GraphicsName-BaseAdr-1 addi r16,r0,'g' stbu r16,1(r24) addi r16,r0,'r' stbu r16,1(r24) addi r16,r0,'a' stbu r16,1(r24) addi r16,r0,'p' stbu r16,1(r24) addi r16,r0,'h' stbu r16,1(r24) addi r16,r0,'i' stbu r16,1(r24) addi r16,r0,'c' stbu r16,1(r24) addi r16,r0,'s' stbu r16,1(r24) addi r16,r0,'.' stbu r16,1(r24) addi r16,r0,'l' stbu r16,1(r24) addi r16,r0,'i' stbu r16,1(r24) addi r16,r0,'b' stbu r16,1(r24) addi r16,r0,'r' stbu r16,1(r24) addi r16,r0,'a' stbu r16,1(r24) addi r16,r0,'r' stbu r16,1(r24) addi r16,r0,'y' stbu r16,1(r24) addi r16,r0,0 stbu r16,1(r24) ;library = OpenLibrary(libName, version) ;d0 a1 d0 ;--------------------------------------- addi r16,r0,0 ;r0 meaning 0 ;d0 addi r25,r15,GraphicsName-BaseAdr ;a1 addi r0,r0,( 1<<(31-25) )|2 ;input-mask: map a1&a6 addi r1,r0,1<<(31-16) ;output-mask: map d0 rlwinm r1,r1,0,16,31 ;clear the upper halveword lwz r30,ExecBase-BaseAdr(r15) lwz r2,_LVOOpenLibrary+2(r30) sc ;call it cmpi CR0,L_32bit,r16,0 bc BO_true,crf_eq,ERROR_NoGraphics stw r16,GraphicsBase-BaseAdr(r15) ;"input.device",0 addi r1,r15,InputName-BaseAdr-1 addi r0,r0,'i' stbu r0,1(r1) addi r0,r0,'n' stbu r0,1(r1) addi r0,r0,'p' stbu r0,1(r1) addi r0,r0,'u' stbu r0,1(r1) addi r0,r0,'t' stbu r0,1(r1) addi r0,r0,'.' stbu r0,1(r1) addi r0,r0,'d' stbu r0,1(r1) addi r0,r0,'e' stbu r0,1(r1) addi r0,r0,'v' stbu r0,1(r1) addi r0,r0,'i' stbu r0,1(r1) addi r0,r0,'c' stbu r0,1(r1) addi r0,r0,'e' stbu r0,1(r1) addi r0,r0,0 stbu r0,1(r1) ;error = OpenDevice(devName, unitNumber, iORequest, flags) ;d0 a0 d0 a1 d1 ;--------------------------------------------------------- addi r24,r15,InputName-BaseAdr ;a0 addi r16,r0,0 ;d0 addi r25,r15,InputIOReq-BaseAdr ;a1 addi r17,r0,0 ;d1 addi r0,r0,( 1<<(31-24) )|( 1<<(31-25) )|2 ;input-mask: map a0/a1/a6 addi r1,r0,0 ;no output-mappings lwz r30,ExecBase-BaseAdr(r15) lwz r2,_LVOOpenDevice+2(r30) sc cmpi CR0,L_32bit,r16,0 ;OpenDevice returns 0 for success bc BO_false,crf_eq,ERROR_NoInput ;get the Input-Base mapped lwz r17,InputIOReq-BaseAdr+MN_SIZE(r15) addi r0,r0,0 addi r1,r0,1<<(31-17) ;map from Amiga to PPC-address space addi r2,r0,0 ;just do the mapping sc stw r17,InputBase-BaseAdr(r15) ;prepare the Screen-Title addi r1,r15,MyScreenTitle-BaseAdr-1 addi r0,r0,'P' stbu r0,1(r1) addi r0,r0,'P' stbu r0,1(r1) addi r0,r0,'C' stbu r0,1(r1) addi r0,r0,'-' stbu r0,1(r1) addi r0,r0,'E' stbu r0,1(r1) addi r0,r0,'m' stbu r0,1(r1) addi r0,r0,'u' stbu r0,1(r1) addi r0,r0,'l' stbu r0,1(r1) addi r0,r0,'a' stbu r0,1(r1) addi r0,r0,'t' stbu r0,1(r1) addi r0,r0,'o' stbu r0,1(r1) addi r0,r0,'r' stbu r0,1(r1) addi r0,r0,' ' stbu r0,1(r1) addi r0,r0,'D' stbu r0,1(r1) addi r0,r0,'e' stbu r0,1(r1) addi r0,r0,'m' stbu r0,1(r1) addi r0,r0,'o' stbu r0,1(r1) addi r0,r0,'(' stbu r0,1(r1) addi r0,r0,'L' stbu r0,1(r1) addi r0,r0,'M' stbu r0,1(r1) addi r0,r0,'B' stbu r0,1(r1) addi r0,r0,' ' stbu r0,1(r1) addi r0,r0,'t' stbu r0,1(r1) addi r0,r0,'o' stbu r0,1(r1) addi r0,r0,' ' stbu r0,1(r1) addi r0,r0,'q' stbu r0,1(r1) addi r0,r0,'u' stbu r0,1(r1) addi r0,r0,'i' stbu r0,1(r1) addi r0,r0,'t' stbu r0,1(r1) addi r0,r0,')' stbu r0,1(r1) addi r0,r0,0 stbu r0,1(r1) ;map the Title-address addi r16,r15,MyScreenTitle-BaseAdr addi r2,r0,0 ;no call addi r0,r0,1<<(31-16) ;map r16 rlwinm r0,r0,0,16,31 ;clear the upper halveword addi r1,r0,0 ;no address mapping to PPC-address space sc ;setup the NewScreen-structure addi r1,r15,MY_NewScreen-BaseAdr addi r0,r0,0 sth r0,MY_ns_LeftEdge-MY_NewScreen(r1) addi r0,r0,0 sth r0,MY_ns_TopEdge-MY_NewScreen(r1) addi r0,r0,MYSCREEN_WIDTH sth r0,MY_ns_Width-MY_NewScreen(r1) addi r0,r0,MYSCREEN_HEIGHT+MYSCREEN_BARHEIGHT sth r0,MY_ns_Height-MY_NewScreen(r1) addi r0,r0,MYSCREEN_DEPTH sth r0,MY_ns_Depth-MY_NewScreen(r1) addi r0,r0,1 stb r0,MY_ns_DetailPen-MY_NewScreen(r1) addi r0,r0,1 stb r0,MY_ns_BlockPen-MY_NewScreen(r1) addi r0,r0,V_SPRITES sth r0,MY_ns_ViewModes-MY_NewScreen(r1) addi r0,r0,CUSTOMSCREEN sth r0,MY_ns_Type-MY_NewScreen(r1) addi r0,r0,0 stw r0,MY_ns_Font-MY_NewScreen(r1) addi r0,r0,0 stw r16,MY_ns_DefaultTitle-MY_NewScreen(r1) ;use the mapped adr stw r0,MY_ns_Gadgets-MY_NewScreen(r1) addi r0,r0,0 stw r0,MY_ns_CustomBitmap-MY_NewScreen(r1) ;Screen = OpenScreen( NewScreen ) ;d0 a0 ;-------------------------------- addi r24,r15,MY_NewScreen-BaseAdr ;a1 addi r0,r0,( 1<<(31-24) )|2 ;input:map a1+a6 addi r1,r0,1<<(31-16) ;output:map d0 rlwinm r1,r1,0,16,31 ;clear the upper halveword lwz r30,IntuitionBase-BaseAdr(r15) lwz r2,_LVOOpenScreen+2(r30) sc cmpi CR0,L_32bit,r16,0 bc BO_true,crf_eq,ERROR_NoScreen stw r16,MyScreen-BaseAdr(r15) ;store our screen ;** allocates temporary rastport for WritePixelArray8 ;** input: r17=original Rastport ;** r15=Base-Address ;** return: r16=0 if success/r16=1 if out of ChipMem ;** (in BOTH cases call FreePlanes to free allocated chipmem) ;** altered: r0-r2/r16-r30 lwz r17,MyScreen-BaseAdr(r15) addi r17,r17,sc_RastPort bl SetupTempRastport cmpi CR0,L_32bit,r16,0 bc BO_false,crf_eq,ERROR_NoTmpRP ;alloc the chunky buffer ;memoryblock = AllocMem(byteSize, attributes) ;d0 d0 d1 ;-------------------------------------------- addi r0,r0,2 ;input:map a6 addi r1,r0,1<<(31-16) ;output:map d0 rlwinm r1,r1,0,16,31 ;clear the upper 16 bits addi r16,r0,0xffff&(MYSCREEN_WIDTH*(MYSCREEN_HEIGHT+2)) rlwinm r16,r16,0,16,31 ;clear the upper 16 bits addis r16,r16,0xffff&((MYSCREEN_WIDTH*(MYSCREEN_HEIGHT+2))>>16) stw r16,ChunkyBufSize-BaseAdr(r15) addi r17,r0,0 ;d1 addis r17,r17,1 ;clear it lwz r30,ExecBase-BaseAdr(r15) lwz r2,_LVOAllocMem+2(r30) sc cmpi CR0,L_32bit,r16,0 bc BO_true,crf_eq,ERROR_NoChunkyBuf stw r16,ChunkyBufAdr-BaseAdr(r15) ;store adr of chunky buffer ;;;wait for left mousebutton to be pressed;;; WaitForMouse: ;***work with the chunky-buffer*** bl DoChunky ;***display the chunky-buffer*** ;count = WritePixelArray8(rp,xstart,ystart,xstop,ystop,array,temprp) ;d0 a0 d0 d1 d2 d3 a2 a1 ;------------------------------------------------------------------- lwz r24,MyScreen-BaseAdr(r15) addi r24,r24,sc_RastPort ;a0 addi r25,r15,TmpRastport-BaseAdr ;a1 lwz r26,ChunkyBufAdr-BaseAdr(r15) ;a2 addi r16,r0,0 ;d0 addi r17,r0,0+MYSCREEN_BARHEIGHT ;d1 addi r18,r0,MYSCREEN_WIDTH-1 ;d2 addi r19,r0,MYSCREEN_HEIGHT-1+MYSCREEN_BARHEIGHT ;d3 addi r0,r0,(1<<(31-24))|(1<<(31-25))|(1<<(31-26))|2 ;map a0/a1/a2/a6 addi r1,r0,0 lwz r30,GraphicsBase-BaseAdr(r15) lwz r2,_LVOWritePixelArray8+2(r30) sc ;qualifier = PeekQualifier() ;d0 ;--------------------------- addi r0,r0,2 ;map a6 addi r1,r0,0 ;no output-mappings lwz r30,InputBase-BaseAdr(r15) lwz r2,_LVOPeekQualifier+2(r30) sc andi. r16,r16,IEQUALIFIER_LEFTBUTTON bc BO_true,crf_eq,WaitForMouse ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;FreeMem(memoryBlock, byteSize) ; a1 d0 ;------------------------------ lwz r25,ChunkyBufAdr-BaseAdr(r15) ;a1 lwz r16,ChunkyBufSize-BaseAdr(r15) ;d0 addi r0,r0,( 1<<(31-25) )|2 ;map a1/a6 addi r1,r0,0 lwz r30,ExecBase-BaseAdr(r15) lwz r2,_LVOFreeMem+2(r30) sc ERROR_NoChunkyBuf: ERROR_NoTmpRP: ;** frees the (partially) allocated bitplanes for the temporary rastport ;** input: r15=base-address ;** altered: r0-r2/r16-r30 bl FreePlanes ;CloseScreen( Screen ) ; a0 ;--------------------- lwz r24,MyScreen-BaseAdr(r15) addi r0,r0,(1<<(31-24))|2 ;map a0&a6 addi r1,r0,0 ;output:map nothing lwz r30,IntuitionBase-BaseAdr(r15) ;execbase in a6 lwz r2,_LVOCloseScreen+2(r30) ;the address to jump to sc ERROR_NoScreen: ;CloseDevice(iORequest) ; a1 ;---------------------- addi r25,r15,InputIOReq-BaseAdr ;a1 addi r0,r0,( 1<<(31-25) )|2 ;map a1&a6 addi r1,r0,0 ;no output-mappings lwz r30,ExecBase-BaseAdr(r15) lwz r2,_LVOCloseDevice+2(r30) sc ERROR_NoInput: ;CloseLibrary(library) ; a1 ;--------------------- lwz r25,GraphicsBase-BaseAdr(r15) addi r0,r0,(1<<(31-25))|2 ;map a1&a6 addi r1,r0,0 ;no output-mappings lwz r30,ExecBase-BaseAdr(r15) ;execbase in A6 lwz r2,_LVOCloseLibrary+2(r30) sc ERROR_NoGraphics: ;CloseLibrary(library) ; a1 ;--------------------- lwz r25,IntuitionBase-BaseAdr(r15) addi r0,r0,(1<<(31-25))|2 ;map a1&a6 addi r1,r0,0 ;no output-mappings lwz r30,ExecBase-BaseAdr(r15) ;execbase in A6 lwz r2,_LVOCloseLibrary+2(r30) sc ERROR_NoIntuition: lwz r0,MainReturnAdr-BaseAdr(r15) ;restore the return-adr mtspr SPR_LR,r0 bclr BO_always,0 ;RETURN ;# # # # # # # # # # # # # # # # # # # # # # # ;;;;;Routines;;;;;; ;** r16....target ;** r17....source ;** r18....size ;**altered: r16,r17,r18,r19 ByteCopy: addi r16,r16,-1 addi r17,r17,-1 ByteCopy_loop: cmpi CR0,L_32bit,r18,0 ;copied all bytes? bclr BO_true,crf_eq ;then return addi r18,r18,-1 lbzu r19,1(r17) stbu r19,1(r16) b ByteCopy_loop ; ; ; ; ; ; ; ; ; ; ;** allocates temporary rastport for WritePixelArray8 ;** input: r17=original Rastport ;** r15=Base-Address ;** return: r16=0 if success/r16=1 if out of ChipMem ;** (in BOTH cases call FreePlanes to free allocated chipmem) ;** altered: r0-r2/r16-r30 SetupTempRastport: mfspr r16,SPR_LR stwu r16,-4(r31) ;save LR onto the stack ;1.copy the rastport structure ;** r16....target ;** r17....source ;** r18....size ;**altered: r16,r17,r18,r19 addi r16,r15,TmpRastport-BaseAdr addi r18,r18,rp_SIZEOF bl ByteCopy ;2.set Layer=NULL addi r16,r15,TmpRastport-BaseAdr ;r16=new rastport addi r17,r0,0 stw r17,rp_Layer(r16) ;3.setup a new Bitmap addi r17,r15,TmpBitmap-BaseAdr addi r0,r0,1<<(31-17) ;map it first addi r1,r0,0 addi r2,r0,0 ;no call sc stw r17,rp_BitMap(r16) ;InitBitMap( bm, depth, width, height ) ; a0 d0 d1 d2 ;-------------------------------------- addi r24,r15,TmpBitmap-BaseAdr ;a0 addi r16,r0,MYSCREEN_DEPTH ;d0 addi r17,r0,MYSCREEN_WIDTH ;d1 addi r18,r0,MYSCREEN_HEIGHT+MYSCREEN_BARHEIGHT ;d2 addi r0,r0,( 1<<(31-24) )|2 ;map a0&a6 addi r1,r0,0 lwz r30,GraphicsBase-BaseAdr(r15) lwz r2,_LVOInitBitMap+2(r30) sc addi r16,r15,TmpBitmap-BaseAdr ;r16=new bitmap ;__set rows=1 addi r17,r0,1 sth r17,bm_Rows(r16) ;__set BytesPerRow addi r17,r0,(MYSCREEN_WIDTH>>3) sth r17,bm_BytesPerRow(r16) ;4.allocate the bitplanes addi r16,r15,TmpBitmap-BaseAdr+bm_Planes-4 ;point to planes-4 addi r17,r0,MYSCREEN_DEPTH SetupTempRastport_allocplanes: cmpi CR0,L_32bit,r17,0 ;all planes done? bc BO_true,crf_eq,SetupTempRastport_success addi r17,r17,-1 stwu r16,-4(r31) ;save r16 to the stack stwu r17,-4(r31) ;save r17 to the stack ;planeptr = AllocRaster( width, height ) ;d0 d0 d1 ;--------------------------------------- addi r16,r0,MYSCREEN_WIDTH ;d0 addi r17,r0,MYSCREEN_HEIGHT+MYSCREEN_BARHEIGHT+2 ;d1 addi r0,r0,2 ;map a6 addi r1,r0,0 ;no output-adrs lwz r30,GraphicsBase-BaseAdr(r15) lwz r2,_LVOAllocRaster+2(r30) sc ori r18,r16,0 ;move the adr to r18 lwz r17,(r31) ;restore r17 from the stack lwzu r16,4(r31) ;restore r16 from the stack addi r31,r31,4 stwu r18,4(r16) cmpi CR0,L_32bit,r18,0 ;out of ChipMem? bc BO_false,crf_eq,SetupTempRastport_allocplanes ;;failed! caller should free allocated planes with FreePlanes addi r16,r0,1 ;indicate failure b SetupTempRastport_quit SetupTempRastport_success: addi r16,r0,0 ;indicate success SetupTempRastport_quit: lwz r17,(r31) ;restore LR from the stack addi r31,r31,4 mtspr SPR_LR,r17 bclr BO_always,0 ;return ; ; ; ; ; ; ; ; ; ; ;** frees the (partially) allocated bitplanes for the temporary rastport ;** input: r15=base-address ;** altered: r0-r2/r16-r30 FreePlanes: addi r16,r15,TmpBitmap-BaseAdr+bm_Planes-4 ;point to planes-4 addi r17,r0,MYSCREEN_DEPTH FreePlanes_loop: cmpi CR0,L_32bit,r17,0 ;freed all? bc BO_true,crf_eq,FreePlanes_done addi r17,r17,-1 lwzu r24,4(r16) cmpi CR0,L_32bit,r24,0 ;no more allocated planes? bc BO_true,crf_eq,FreePlanes_done stwu r16,-4(r31) ;push to stack stwu r17,-4(r31) ;push to stack ;FreeRaster( p, width, height ) ; a0 d0 d1 addi r16,r0,MYSCREEN_WIDTH ;d0 addi r17,r0,MYSCREEN_HEIGHT+MYSCREEN_BARHEIGHT+2 ;d1 addi r0,r0,2 ;map a6 ;no mapping of a0 needed addi r1,r0,0 lwz r30,GraphicsBase-BaseAdr(r15) lwz r2,_LVOFreeRaster+2(r30) sc lwz r17,(r31) ;pop from stack lwzu r16,4(r31) ;pop from stack addi r31,r31,4 b FreePlanes_loop FreePlanes_done: bclr BO_always,0 ;return TmpBitmap:db bm_SIZEOF dup (0) ;bitplanes here remain in Amiga-address space align 4 TmpRastport:db rp_SIZEOF dup (0) align 4 ; ; ; ; ; ; ; ; ; ; ;** does the chunky graphic DoChunky: mfspr r0,SPR_LR stwu r0,-4(r31) ;save the return-address onto the stack ;;clear the buffer ;WritePixelArray8 clears the buffer itself ; lwz r1,ChunkyBufSize-BaseAdr(r15) ; addi r2,r0,0 ; lwz r3,ChunkyBufAdr-BaseAdr(r15) ; addi r3,r3,-4 ; DoChunky_clear: ; stwu r2,4(r3) ; addi r1,r1,-4 ; cmpi CR0,L_32bit,r1,0 ; bc BO_false,crf_eq,DoChunky_clear ;;do some moving graphics lwz r1,DoChunky_counter-BaseAdr(r15) addi r1,r1,2 lwz r2,DoChunky_xy-BaseAdr(r15) cmpi CR0,L_32bit,r2,0 bc BO_true,crf_eq,DoChunky_xmode addi r17,r0,0 ;x1 subfic r18,r1,MYSCREEN_HEIGHT-1 ;y1 addi r19,r0,MYSCREEN_WIDTH-1 ;x2 or r20,r1,r1 ;y2 cmpi CR0,L_32bit,r1,MYSCREEN_HEIGHT-1 bc BO_true,crf_lt,DoChunky_ymode_notyet xori r2,r2,1 stw r2,DoChunky_xy-BaseAdr(r15) addi r1,r0,0 ;counter to zero DoChunky_ymode_notyet: b DoChunky_set DoChunky_xmode: or r17,r1,r1 ;x1 addi r18,r0,0 ;y1 subfic r19,r1,MYSCREEN_WIDTH-1 ;x2 addi r20,r0,MYSCREEN_HEIGHT-1 ;y2 cmpi CR0,L_32bit,r1,MYSCREEN_WIDTH-1 bc BO_true,crf_lt,DoChunky_xmode_notyet xori r2,r2,1 stw r2,DoChunky_xy-BaseAdr(r15) addi r1,r0,0 ;counter to zero DoChunky_xmode_notyet: DoChunky_set: stw r1,DoChunky_counter-BaseAdr(r15) lwz r16,ChunkyBufAdr-BaseAdr(r15) ;buffer addi r21,r0,10 ;color addi r22,r0,MYSCREEN_WIDTH ;buffer width bl DrawChunkyLine lwz r0,0(r31) ;restore LR from the stack addi r31,r31,4 mtspr SPR_LR,r0 bclr BO_always,0 ;return DoChunky_xy:dd 0 ;0/1 DoChunky_counter:dd 0 ; ; ; ; ; ; ; ; ; ;** r16....Chunky-Buffer ;** r17....x-start ;** r18....y-start ;** r19....x-stop ;** r20....y-stop ;** r21....color(in lower 8 bits) ;** r22....buffer width ;** altered: r16-r30 DrawChunkyLine: mullw r30,r18,r22 ;y-offset add r30,r30,r17 ;x-offset add r16,r30,r16 ;r16:address of start-pixel addi r25,r0,1 ;r25:y-stepping addi r26,r0,1 ;r26:x-stepping subf. r30,r17,r19 ;x2-x1 or r28,r30,r30 ;r28:dx bc BO_false,crf_lt,DrawChunkyLine_dxpositive neg r30,r30 neg r26,r26 DrawChunkyLine_dxpositive: subf. r29,r18,r20 ;y2-y1 or r27,r29,r29 ;r27:dy bc BO_true,crf_gt,DrawChunkyLine_dypositive bc BO_false,crf_eq,DrawChunkyLine_dynegative cmpi CR0,L_32bit,r30,0 ;startpixel=endpixel? bc BO_true,crf_eq,DrawChunkyLine_onepixel DrawChunkyLine_dynegative: neg r29,r29 neg r25,r25 DrawChunkyLine_dypositive: cmp CR0,L_32bit,r29,r30 ;abs(dy) > abs(dx) ? bc BO_true,crf_gt,DrawChunkyLine_ymode rlwinm r27,r27,8,0,31-8 ;r27:dy*256 divw r27,r27,r30 ;r27:(dy*256)/abs(dx) addi r25,r0,0 ;r25:y-offset add r28,r26,r28 ;abs(r28):number of pixels DrawChunkyLine_xloop: srawi r29,r25,8 addze r29,r29 ;/256 mullw r29,r29,r22 ;*bufferwidth stbx r21,r29,r16 ;set one pixel add r25,r25,r27 ;add to y-offset add r16,r16,r26 ;step in x-direction subf. r28,r26,r28 ;count the pixels bc BO_false,crf_eq,DrawChunkyLine_xloop bclr BO_always,0 ;return DrawChunkyLine_onepixel: stb r21,0(r16) bclr BO_always,0 ;return DrawChunkyLine_ymode: rlwinm r28,r28,8,0,31-8 ;r28:dx*256 divw r28,r28,r29 ;r28:(dx*256)/abs(dy) addi r26,r0,0 ;r26:x-offset mullw r29,r25,r22 ;r29:y-stepping*bufferwidth add r27,r25,r27 ;abs(r27):number of pixels DrawChunkyLine_yloop: srawi r30,r26,8 addze r30,r30 ;/256 stbx r21,r30,r16 add r26,r28,r26 ;add to x-offset add r16,r16,r29 ;step in y-direction subf. r27,r25,r27 bc BO_false,crf_eq,DrawChunkyLine_yloop bclr BO_always,0 ;return ;# # # # # # # # # # # # # # # # # # # # # # # MainReturnAdr:dd 0 ExecBase:dd 0 IntuitionBase:dd 0 GraphicsBase:dd 0 InputBase:dd 0 MyScreen:dd 0 ChunkyBufAdr:dd 0 ChunkyBufSize:dd 0 align 4 MY_NewScreen: MY_ns_LeftEdge: dw 0 MY_ns_TopEdge: dw 0 MY_ns_Width: dw 0 MY_ns_Height: dw 0 MY_ns_Depth: dw 0 MY_ns_DetailPen:db 0 MY_ns_BlockPen: db 0 MY_ns_ViewModes:dw 0 MY_ns_Type: dw 0 MY_ns_Font: dd 0 MY_ns_DefaultTitle:dd 0 MY_ns_Gadgets: dd 0 MY_ns_CustomBitmap:dd 0 align 4 InputIOReq:db 400 dup (0) align 4 ;"intuition.library",0 IntuitionName:db "xxxxxxxxxxxxxxxxxxXXXX" ;"graphics.library",0 GraphicsName:db "xxxxxxxxxxxxxxxxxXXXX" ;"input.device",0 InputName:db "xxxxxxxxxxxxxXXXX" MyScreenTitle:db "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" align 4 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