From 1981af0bbdc75d89c84ed08d6b5554bd200fb9ae Mon Sep 17 00:00:00 2001 From: Scott Hutter Date: Mon, 23 Jul 2018 15:54:15 -0500 Subject: [PATCH] tgi driver for c128 VIC-II --- libsrc/c128/tgi/c128-hi.s | 884 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 884 insertions(+) create mode 100644 libsrc/c128/tgi/c128-hi.s diff --git a/libsrc/c128/tgi/c128-hi.s b/libsrc/c128/tgi/c128-hi.s new file mode 100644 index 000000000..2286ee210 --- /dev/null +++ b/libsrc/c128/tgi/c128-hi.s @@ -0,0 +1,884 @@ +; +; Graphics driver for the 320x200x2 mode on the C128. +; +; Based on Stephen L. Judd's GRLIB code. +; +; 2017-01-13, Greg King +; 2018-03-13, Sven Klose +; 2018-07-22, Scott Hutter +; + + .include "zeropage.inc" + + .include "tgi-kernel.inc" + .include "tgi-error.inc" + + .macpack generic + .macpack module + + +; ------------------------------------------------------------------------ +; Header. Includes jump table and constants. + + module_header _c128_hi_tgi + +; First part of the header is a structure that has a magic and defines the +; capabilities of the driver + + .byte $74, $67, $69 ; "tgi" + .byte TGI_API_VERSION ; TGI API version number + .addr $0000 ; Library reference + .word 320 ; X resolution + .word 200 ; Y resolution + .byte 2 ; Number of drawing colors + .byte 1 ; Number of screens available + .byte 8 ; System font X size + .byte 8 ; System font Y size + .word $00D4 ; Aspect ratio (based on 4/3 display) + .byte 0 ; TGI driver flags + +; Next comes the jump table. With the exception of IRQ, all entries must be +; valid and may point to an RTS for test versions (function not implemented). + + .addr INSTALL + .addr UNINSTALL + .addr INIT + .addr DONE + .addr GETERROR + .addr CONTROL + .addr CLEAR + .addr SETVIEWPAGE + .addr SETDRAWPAGE + .addr SETCOLOR + .addr SETPALETTE + .addr GETPALETTE + .addr GETDEFPALETTE + .addr SETPIXEL + .addr GETPIXEL + .addr LINE + .addr BAR + .addr TEXTSTYLE + .addr OUTTEXT + +; ------------------------------------------------------------------------ +; Data. + +; Variables mapped to the zero page segment variables. Some of these are +; used for passing parameters to the driver. + +X1 := ptr1 +Y1 := ptr2 +X2 := ptr3 +Y2 := ptr4 +TEXT := ptr3 + +TEMP := tmp4 +TEMP2 := sreg +POINT := regsave + +CHUNK := X2 ; Used in the line routine +OLDCHUNK := X2+1 ; Dito + +; Absolute variables used in the code + +.bss + +ERROR: .res 1 ; Error code +PALETTE: .res 2 ; The current palette + +BITMASK: .res 1 ; $00 = clear, $FF = set pixels + +; INIT/DONE +OLDD018: .res 1 ; Old register value + +; Line routine stuff +DX: .res 2 +DY: .res 2 + +; BAR variables +X1SAVE: .res 2 +Y1SAVE: .res 2 +X2SAVE: .res 2 +Y2SAVE: .res 2 + +; Text output stuff +TEXTMAGX: .res 1 +TEXTMAGY: .res 1 +TEXTDIR: .res 1 + +; Constants and tables + +.rodata + +DEFPALETTE: .byte $00, $01 ; White on black +PALETTESIZE = * - DEFPALETTE + +BITTAB: .byte $80,$40,$20,$10,$08,$04,$02,$01 +BITCHUNK: .byte $FF,$7F,$3F,$1F,$0F,$07,$03,$01 + +CHARROM := $D000 ; Character rom base address +CBASE := $5C00 ; Color memory base address +VBASE := $6000 ; Video memory base address + ; BASE + $4000 for each bank above VIC bank 0 + ; $2000 = VIC bank 0 (base) + ; $6000 = VIC bank 1 + ; $A000 = VIC bank 2 + ; $E000 = VIC bank 3 + + +.code + +; ------------------------------------------------------------------------ +; INSTALL routine. Is called after the driver is loaded into memory. May +; initialize anything that has to be done just once. Is probably empty +; most of the time. +; +; Must set an error code: NO +; + +INSTALL: +; rts ; fall through + + +; ------------------------------------------------------------------------ +; UNINSTALL routine. Is called before the driver is removed from memory. May +; clean up anything done by INSTALL but is probably empty most of the time. +; +; Must set an error code: NO +; + +UNINSTALL: + rts + + +; ------------------------------------------------------------------------ +; INIT: Changes an already installed device from text mode to graphics +; mode. +; Note that INIT/DONE may be called multiple times while the driver +; is loaded, while INSTALL is only called once, so any code that is needed +; to initializes variables and so on must go here. Setting palette and +; clearing the screen is not needed because this is called by the graphics +; kernel later. +; The graphics kernel will never call INIT when a graphics mode is already +; active, so there is no need to protect against that. +; +; Must set an error code: YES +; + +INIT: +; Initialize variables + ldx #$FF + stx BITMASK + +; Switch into graphics mode + + ; select video bank + ; bank 0=3 ($0-$3FFF) (default) + ; bank 1=2 ($4000-$7FFF) * + ; bank 2=1 ($8000-$BFFF) + ; bank 3=0 ($C000-$FFFF) + lda $DD00 + and #$FC + ora #$02 ; bank number 1 ($4000) + sta $DD00 + + ; Switch to bitmap mode + lda $D8 + ora #$20 + sta $D8 + +DONE1: lda #TGI_ERR_OK + sta ERROR + rts + +; ------------------------------------------------------------------------ +; DONE: Will be called to switch the graphics device back into text mode. +; The graphics kernel will never call DONE when no graphics mode is active, +; so there is no need to protect against that. +; +; Must set an error code: NO +; + +DONE: ; select video bank + lda $DD00 + and #$FC + ora #$03 ; bank 0=3 ($0-$3FFF), 1=2 ($4000-$7FFF), 2=1 ($8000-$BFFF), 3=0 ($C000-$FFFF) + sta $DD00 + + lda $0A2D ; change screen ram location + AND #$0F + ORA #$10 ; $0400 + STA $0A2D + + LDA #$00 ; switch back to text mode + STA $D8 + rts + +; ------------------------------------------------------------------------ +; GETERROR: Return the error code in A and clear it. + +GETERROR: + ldx #TGI_ERR_OK + lda ERROR + stx ERROR + rts + +; ------------------------------------------------------------------------ +; CONTROL: Platform/driver specific entry point. +; +; Must set an error code: YES +; + +CONTROL: + lda #TGI_ERR_INV_FUNC + sta ERROR + rts + +; ------------------------------------------------------------------------ +; CLEAR: Clears the screen. +; +; Must set an error code: NO +; + +CLEAR: + ldy #$00 + tya +@L1: sta VBASE+$0000,y + sta VBASE+$0100,y + sta VBASE+$0200,y + sta VBASE+$0300,y + sta VBASE+$0400,y + sta VBASE+$0500,y + sta VBASE+$0600,y + sta VBASE+$0700,y + sta VBASE+$0800,y + sta VBASE+$0900,y + sta VBASE+$0A00,y + sta VBASE+$0B00,y + sta VBASE+$0C00,y + sta VBASE+$0D00,y + sta VBASE+$0E00,y + sta VBASE+$0F00,y + sta VBASE+$1000,y + sta VBASE+$1100,y + sta VBASE+$1200,y + sta VBASE+$1300,y + sta VBASE+$1400,y + sta VBASE+$1500,y + sta VBASE+$1600,y + sta VBASE+$1700,y + sta VBASE+$1800,y + sta VBASE+$1900,y + sta VBASE+$1A00,y + sta VBASE+$1B00,y + sta VBASE+$1C00,y + sta VBASE+$1D00,y + sta VBASE+$1E00,y + sta VBASE+$1E40,y ; preserve vectors + iny + bne @L1 + rts + +; ------------------------------------------------------------------------ +; SETVIEWPAGE: Set the visible page. Called with the new page in A (0..n). +; The page number is already checked to be valid by the graphics kernel. +; +; Must set an error code: NO (will only be called if page ok) +; + +SETVIEWPAGE: +; rts ; fall through + +; ------------------------------------------------------------------------ +; SETDRAWPAGE: Set the drawable page. Called with the new page in A (0..n). +; The page number is already checked to be valid by the graphics kernel. +; +; Must set an error code: NO (will only be called if page ok) +; + +SETDRAWPAGE: + rts + +; ------------------------------------------------------------------------ +; SETCOLOR: Set the drawing color (in A). The new color is already checked +; to be in a valid range (0..maxcolor-1). +; +; Must set an error code: NO (will only be called if color ok) +; + +SETCOLOR: + tax + beq @L1 + lda #$FF +@L1: sta BITMASK + rts + +; ------------------------------------------------------------------------ +; SETPALETTE: Set the palette (not available with all drivers/hardware). +; A pointer to the palette is passed in ptr1. Must set an error if palettes +; are not supported +; +; Must set an error code: YES +; + +SETPALETTE: + ldy #PALETTESIZE - 1 +@L1: lda (ptr1),y ; Copy the palette + and #$0F ; Make a valid color + sta PALETTE,y + dey + bpl @L1 + +; Get the color entries from the palette + + lda PALETTE+1 ; Foreground color + asl a + asl a + asl a + asl a + ora PALETTE ; Background color + tax + +; Initialize the color map with the new color settings (it is below the +; I/O area) + + ldy #$00 + sei + lda $01 ; Get ROM config + pha ; Save it + and #%11111100 ; Clear bit 0 and 1 + sta $01 + txa ; Load color code +@L2: sta CBASE+$0000,y + sta CBASE+$0100,y + sta CBASE+$0200,y + sta CBASE+$02e8,y + iny + bne @L2 + pla + sta $01 + cli + +; Done, reset the error code + + lda #TGI_ERR_OK + sta ERROR + rts + +; ------------------------------------------------------------------------ +; GETPALETTE: Return the current palette in A/X. Even drivers that cannot +; set the palette should return the default palette here, so there's no +; way for this function to fail. +; +; Must set an error code: NO +; + +GETPALETTE: + lda #PALETTE + rts + +; ------------------------------------------------------------------------ +; GETDEFPALETTE: Return the default palette for the driver in A/X. All +; drivers should return something reasonable here, even drivers that don't +; support palettes, otherwise the caller has no way to determine the colors +; of the (not changeable) palette. +; +; Must set an error code: NO (all drivers must have a default palette) +; + +GETDEFPALETTE: + lda #DEFPALETTE + rts + +; ------------------------------------------------------------------------ +; SETPIXEL: Draw one pixel at X1/Y1 = ptr1/ptr2 with the current drawing +; color. The coordinates passed to this function are never outside the +; visible screen area, so there is no need for clipping inside this function. +; +; Must set an error code: NO +; + +SETPIXEL: + jsr CALC ; Calculate coordinates + + sei ; Get underneath ROM + lda $01 + pha + lda #$34 + sta $01 + + lda (POINT),Y + eor BITMASK + and BITTAB,X + eor (POINT),Y + sta (POINT),Y + + pla + sta $01 + cli + +@L9: rts + +; ------------------------------------------------------------------------ +; GETPIXEL: Read the color value of a pixel and return it in A/X. The +; coordinates passed to this function are never outside the visible screen +; area, so there is no need for clipping inside this function. + + +GETPIXEL: + jsr CALC ; Calculate coordinates + + sei ; Get underneath ROM + lda $01 + pha + lda #$34 + sta $01 + + lda (POINT),Y + ldy #$00 + and BITTAB,X + beq @L1 + iny + +@L1: pla + sta $01 + cli + + tya ; Get color value into A + ldx #$00 ; Clear high byte + rts + +; ------------------------------------------------------------------------ +; LINE: Draw a line from X1/Y1 to X2/Y2, where X1/Y1 = ptr1/ptr2 and +; X2/Y2 = ptr3/ptr4 using the current drawing color. +; +; X1,X2 etc. are set up above (x2=LINNUM in particular) +; Format is LINE x2,y2,x1,y1 +; +; Must set an error code: NO +; + +LINE: + +@CHECK: lda X2 ;Make sure x1=y1? + lda Y1 ;Otherwise dy=y1-y2 + sec + sbc Y2 + tay + ldx #$88 ;DEY + +@DYPOS: sty DY ; 8-bit DY -- FIX ME? + stx YINCDEC + stx XINCDEC + + jsr CALC ; Set up .X, .Y, and POINT + lda BITCHUNK,X + sta OLDCHUNK + sta CHUNK + + sei ; Get underneath ROM + lda #$34 + sta $01 + + ldx DY + cpx DX ;Who's bigger: dy or dx? + bcc STEPINX ;If dx, then... + lda DX+1 + bne STEPINX + +; +; Big steps in Y +; +; To simplify my life, just use PLOT to plot points. +; +; No more! +; Added special plotting routine -- cool! +; +; X is now counter, Y is y-coordinate +; +; On entry, X=DY=number of loop iterations, and Y= +; Y1 AND #$07 +STEPINY: + lda #00 + sta OLDCHUNK ;So plotting routine will work right + lda CHUNK + lsr ;Strip the bit + eor CHUNK + sta CHUNK + txa + beq YCONT2 ;If dy=0, it's just a point +@CONT: lsr ;Init counter to dy/2 +; +; Main loop +; +YLOOP: sta TEMP + + lda (POINT),y + eor BITMASK + and CHUNK + eor (POINT),y + sta (POINT),y +YINCDEC: + iny ;Advance Y coordinate + cpy #8 + bcc @CONT ;No prob if Y=0..7 + jsr FIXY +@CONT: lda TEMP ;Restore A + sec + sbc DX + bcc YFIXX +YCONT: dex ;X is counter + bne YLOOP +YCONT2: lda (POINT),y ;Plot endpoint + eor BITMASK + and CHUNK + eor (POINT),y + sta (POINT),y + lda #$36 + sta $01 + cli + rts + +YFIXX: ;x=x+1 + adc DY + lsr CHUNK + bne YCONT ;If we pass a column boundary... + ror CHUNK ;then reset CHUNK to $80 + sta TEMP2 + lda POINT ;And add 8 to POINT + adc #8 + sta POINT + bcc @CONT + inc POINT+1 +@CONT: lda TEMP2 + dex + bne YLOOP + beq YCONT2 + +; +; Big steps in X direction +; +; On entry, X=DY=number of loop iterations, and Y= +; Y1 AND #$07 + +.bss +COUNTHI: + .byte $00 ;Temporary counter + ;only used once +.code +STEPINX: + ldx DX + lda DX+1 + sta COUNTHI + cmp #$80 + ror ;Need bit for initialization + sta Y1 ;High byte of counter + txa + bne @CONT ;Could be $100 + dec COUNTHI +@CONT: ror +; +; Main loop +; +XLOOP: lsr CHUNK + beq XFIXC ;If we pass a column boundary... +XCONT1: sbc DY + bcc XFIXY ;Time to step in Y? +XCONT2: dex + bne XLOOP + dec COUNTHI ;High bits set? + bpl XLOOP + + lsr CHUNK ;Advance to last point + jsr LINEPLOT ;Plot the last chunk + lda #$36 + sta $01 + cli + rts +; +; CHUNK has passed a column, so plot and increment pointer +; and fix up CHUNK, OLDCHUNK. +; +XFIXC: sta TEMP + jsr LINEPLOT + lda #$FF + sta CHUNK + sta OLDCHUNK + lda POINT + clc + adc #8 + sta POINT + lda TEMP + bcc XCONT1 + inc POINT+1 + jmp XCONT1 +; +; Check to make sure there isn't a high bit, plot chunk, +; and update Y-coordinate. +; +XFIXY: dec Y1 ;Maybe high bit set + bpl XCONT2 + adc DX + sta TEMP + lda DX+1 + adc #$FF ;Hi byte + sta Y1 + + jsr LINEPLOT ;Plot chunk + lda CHUNK + sta OLDCHUNK + + lda TEMP +XINCDEC: + iny ;Y-coord + cpy #8 ;0..7 is ok + bcc XCONT2 + sta TEMP + jsr FIXY + lda TEMP + jmp XCONT2 + +; +; Subroutine to plot chunks/points (to save a little +; room, gray hair, etc.) +; +LINEPLOT: ; Plot the line chunk + lda (POINT),Y + eor BITMASK + ora CHUNK + and OLDCHUNK + eor CHUNK + eor (POINT),Y + sta (POINT),Y + rts + +; +; Subroutine to fix up pointer when Y decreases through +; zero or increases through 7. +; +FIXY: cpy #255 ;Y=255 or Y=8 + beq @DECPTR + +@INCPTR: ;Add 320 to pointer + ldy #0 ;Y increased through 7 + lda POINT + adc #<320 + sta POINT + lda POINT+1 + adc #>320 + sta POINT+1 + rts + +@DECPTR: ;Okay, subtract 320 then + ldy #7 ;Y decreased through 0 + lda POINT + sec + sbc #<320 + sta POINT + lda POINT+1 + sbc #>320 + sta POINT+1 + rts + +; ------------------------------------------------------------------------ +; BAR: Draw a filled rectangle with the corners X1/Y1, X2/Y2, where +; X1/Y1 = ptr1/ptr2 and X2/Y2 = ptr3/ptr4 using the current drawing color. +; Contrary to most other functions, the graphics kernel will sort and clip +; the coordinates before calling the driver, so on entry the following +; conditions are valid: +; X1 <= X2 +; Y1 <= Y2 +; (X1 >= 0) && (X1 < XRES) +; (X2 >= 0) && (X2 < XRES) +; (Y1 >= 0) && (Y1 < YRES) +; (Y2 >= 0) && (Y2 < YRES) +; +; Must set an error code: NO +; + +; Note: This function needs optimization. It's just a cheap translation of +; the original C wrapper and could be written much smaller (besides that, +; calling LINE is not a good idea either). + +BAR: lda Y2 + sta Y2SAVE + lda Y2+1 + sta Y2SAVE+1 + + lda X2 + sta X2SAVE + lda X2+1 + sta X2SAVE+1 + + lda Y1 + sta Y1SAVE + lda Y1+1 + sta Y1SAVE+1 + + lda X1 + sta X1SAVE + lda X1+1 + sta X1SAVE+1 + +@L1: lda Y1 + sta Y2 + lda Y1+1 + sta Y2+1 + jsr LINE + + lda Y1SAVE + cmp Y2SAVE + bne @L2 + lda Y1SAVE + cmp Y2SAVE + beq @L4 + +@L2: inc Y1SAVE + bne @L3 + inc Y1SAVE+1 + +@L3: lda Y1SAVE + sta Y1 + lda Y1SAVE+1 + sta Y1+1 + + lda X1SAVE + sta X1 + lda X1SAVE+1 + sta X1+1 + + lda X2SAVE + sta X2 + lda X2SAVE+1 + sta X2+1 + jmp @L1 + +@L4: rts + + +; ------------------------------------------------------------------------ +; TEXTSTYLE: Set the style used when calling OUTTEXT. Text scaling in X and Y +; direction is passend in X/Y, the text direction is passed in A. +; +; Must set an error code: NO +; + +TEXTSTYLE: + stx TEXTMAGX + sty TEXTMAGY + sta TEXTDIR + rts + + +; ------------------------------------------------------------------------ +; OUTTEXT: Output text at X/Y = ptr1/ptr2 using the current color and the +; current text style. The text to output is given as a zero terminated +; string with address in ptr3. +; +; Must set an error code: NO +; + +OUTTEXT: + +; Calculate a pointer to the representation of the character in the +; character ROM + + ldx #((>(CHARROM + $0800)) >> 3) + ldy #0 + lda (TEXT),y + bmi @L1 + ldx #((>(CHARROM + $0000)) >> 3) +@L1: stx ptr4+1 + asl a + rol ptr4+1 + asl a + rol ptr4+1 + asl a + rol ptr4+1 + sta ptr4 + + + + + + rts + +; ------------------------------------------------------------------------ +; Calculate all variables to plot the pixel at X1/Y1. + +CALC: lda Y1 + sta TEMP2 + and #7 + tay + lda Y1+1 + lsr ; Neg is possible + ror TEMP2 + lsr + ror TEMP2 + lsr + ror TEMP2 + + lda #00 + sta POINT + lda TEMP2 + cmp #$80 + ror + ror POINT + cmp #$80 + ror + ror POINT ; row*64 + adc TEMP2 ; +row*256 + clc + adc #>VBASE ; +bitmap base + sta POINT+1 + + lda X1 + tax + and #$F8 + clc + adc POINT ; +(X AND #$F8) + sta POINT + lda X1+1 + adc POINT+1 + sta POINT+1 + txa + and #7 + tax + rts -- 2.39.5