mirror of
https://github.com/irmen/prog8.git
synced 2024-07-10 23:29:02 +00:00
ee81da14d6
programs will now be a lot smaller than before if they use gfx2 (or monogfx if they were only using monochrome drawing) monogfx also fixes some drawing errors with small horizontal lines, and stippled vertical lines.
899 lines
30 KiB
Lua
899 lines
30 KiB
Lua
; Bitmap pixel graphics routines for the CommanderX16
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; Custom routines to use the full-screen 640x480 and 320x240 screen modes.
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; (These modes are not supported by the documented GRAPH_xxxx kernal routines)
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;
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; No text layer is currently shown, text can be drawn as part of the bitmap itself.
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; Note: for similar graphics routines that also work on the C-64, use the "graphics" module instead.
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; Note: for identical routines for a monochrome 1 bpp screen, use the "monogfx" module instead.
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; Note: for color palette manipulation, use the "palette" module or write Vera registers yourself.
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; Note: this library implements code for various resolutions and color depths. This takes up memory.
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; If you're memory constrained you should probably not use this built-in library,
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; but make a copy in your project only containing the code for the required resolution.
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;
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;
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; SCREEN MODE LIST:
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; mode 0 = reset back to default text mode
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; mode 1 = bitmap 320 x 240 x 256c (8 bpp)
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; mode 2 = bitmap 640 x 480 x 4c (2 bpp. there's not enough vram for more colors in hires mode.)
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; mode 3 = bitmap 320 x 240 x 16c (not yet implemented: just use 256c, there's enough vram for that)
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; mode 4 = bitmap 320 x 240 x 4c (not yet implemented: just use 256c, there's enough vram for that)
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; higher color dephts in highres are not supported due to lack of VRAM
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gfx2 {
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%option no_symbol_prefixing
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; read-only control variables:
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ubyte active_mode = 0
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uword width = 0
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uword height = 0
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ubyte bpp = 0
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sub screen_mode(ubyte mode) {
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cx16.VERA_CTRL=0
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when mode {
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1 -> {
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; lores 256c
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cx16.VERA_DC_VIDEO = (cx16.VERA_DC_VIDEO & %11001111) | %00100000 ; enable only layer 1
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cx16.VERA_DC_HSCALE = 64
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cx16.VERA_DC_VSCALE = 64
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cx16.VERA_L1_CONFIG = %00000111
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cx16.VERA_L1_MAPBASE = 0
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cx16.VERA_L1_TILEBASE = 0
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width = 320
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height = 240
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bpp = 8
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}
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2 -> {
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; highres 4c
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cx16.VERA_DC_VIDEO = (cx16.VERA_DC_VIDEO & %11001111) | %00100000 ; enable only layer 1
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cx16.VERA_DC_HSCALE = 128
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cx16.VERA_DC_VSCALE = 128
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cx16.VERA_L1_CONFIG = %00000101
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cx16.VERA_L1_MAPBASE = 0
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cx16.VERA_L1_TILEBASE = %00000001
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width = 640
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height = 480
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bpp = 2
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}
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else -> {
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; back to default text mode
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cx16.r15L = cx16.VERA_DC_VIDEO & %00000111 ; retain chroma + output mode
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cbm.CINT()
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cx16.VERA_DC_VIDEO = (cx16.VERA_DC_VIDEO & %11111000) | cx16.r15L
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width = 0
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height = 0
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bpp = 0
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mode = 0
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}
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}
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active_mode = mode
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if bpp
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clear_screen()
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}
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sub clear_screen() {
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position(0, 0)
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when active_mode {
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1 -> {
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; lores 256c
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repeat 240/2
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cs_innerloop640()
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}
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2 -> {
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; highres 4c
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repeat 480/4
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cs_innerloop640()
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}
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}
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position(0, 0)
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}
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sub rect(uword xx, uword yy, uword rwidth, uword rheight, ubyte color) {
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if rwidth==0 or rheight==0
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return
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horizontal_line(xx, yy, rwidth, color)
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if rheight==1
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return
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horizontal_line(xx, yy+rheight-1, rwidth, color)
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vertical_line(xx, yy+1, rheight-2, color)
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if rwidth==1
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return
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vertical_line(xx+rwidth-1, yy+1, rheight-2, color)
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}
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sub fillrect(uword xx, uword yy, uword rwidth, uword rheight, ubyte color) {
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if rwidth==0
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return
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repeat rheight {
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horizontal_line(xx, yy, rwidth, color)
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yy++
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}
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}
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sub horizontal_line(uword xx, uword yy, uword length, ubyte color) {
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if length==0
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return
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when active_mode {
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1 -> {
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; lores 256c
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position(xx, yy)
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%asm {{
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lda color
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ldx length+1
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beq +
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ldy #0
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- sta cx16.VERA_DATA0
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iny
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bne -
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dex
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bne -
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+ ldy length ; remaining
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beq +
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- sta cx16.VERA_DATA0
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dey
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bne -
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+
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}}
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}
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2 -> {
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; highres 4c ....also mostly usable for lores 4c?
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color &= 3
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ubyte[4] colorbits
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ubyte ii
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for ii in 3 downto 0 {
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colorbits[ii] = color
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color <<= 2
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}
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void addr_mul_24_for_highres_4c(yy, xx) ; 24 bits result is in r0 and r1L (highest byte)
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%asm {{
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lda cx16.VERA_ADDR_H
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and #%00000111 ; no auto advance
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sta cx16.VERA_ADDR_H
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stz cx16.VERA_CTRL ; setup vera addr 0
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lda cx16.r1
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and #1
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sta cx16.VERA_ADDR_H
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lda cx16.r0
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sta cx16.VERA_ADDR_L
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lda cx16.r0+1
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sta cx16.VERA_ADDR_M
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ldx xx
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}}
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repeat length {
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%asm {{
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txa
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and #3
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tay
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lda cx16.VERA_DATA0
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and gfx2.plot.mask4c,y
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ora colorbits,y
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sta cx16.VERA_DATA0
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cpy #%00000011 ; next vera byte?
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bne ++
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inc cx16.VERA_ADDR_L
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bne ++
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inc cx16.VERA_ADDR_M
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+ bne +
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inc cx16.VERA_ADDR_H
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+ inx ; next pixel
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}}
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}
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}
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}
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}
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sub vertical_line(uword xx, uword yy, uword lheight, ubyte color) {
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when active_mode {
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1 -> {
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; lores 256c
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; set vera auto-increment to 320 pixel increment (=next line)
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position(xx,yy)
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cx16.VERA_ADDR_H = cx16.VERA_ADDR_H & %00000111 | (14<<4)
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%asm {{
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ldy lheight
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beq +
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lda color
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- sta cx16.VERA_DATA0
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dey
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bne -
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+
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}}
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}
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2 -> {
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; highres 4c
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; use TWO vera adress pointers simultaneously one for reading, one for writing, so auto-increment is possible
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if lheight==0
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return
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position2(xx,yy,true)
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set_both_strides(13) ; 160 increment = 1 line in 640 px 4c mode
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;; color &= 3
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;; color <<= gfx2.plot.shift4c[lsb(xx) & 3]
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cx16.r2L = lsb(xx) & 3
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when color & 3 {
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1 -> color = gfx2.plot.shiftedleft_4c_1[cx16.r2L]
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2 -> color = gfx2.plot.shiftedleft_4c_2[cx16.r2L]
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3 -> color = gfx2.plot.shiftedleft_4c_3[cx16.r2L]
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}
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ubyte @shared mask = gfx2.plot.mask4c[lsb(xx) & 3]
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repeat lheight {
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%asm {{
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lda cx16.VERA_DATA0
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and mask
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ora color
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sta cx16.VERA_DATA1
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}}
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}
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}
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}
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sub set_both_strides(ubyte stride) {
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stride <<= 4
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cx16.VERA_CTRL = 0
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cx16.VERA_ADDR_H = cx16.VERA_ADDR_H & %00000111 | stride
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cx16.VERA_CTRL = 1
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cx16.VERA_ADDR_H = cx16.VERA_ADDR_H & %00000111 | stride
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}
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}
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sub line(uword @zp x1, uword @zp y1, uword @zp x2, uword @zp y2, ubyte color) {
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; Bresenham algorithm.
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; This code special-cases various quadrant loops to allow simple ++ and -- operations.
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if y1>y2 {
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; make sure dy is always positive to have only 4 instead of 8 special cases
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cx16.r0 = x1
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x1 = x2
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x2 = cx16.r0
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cx16.r0 = y1
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y1 = y2
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y2 = cx16.r0
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}
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word @zp dx = (x2 as word)-x1
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word @zp dy = (y2 as word)-y1
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if dx==0 {
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vertical_line(x1, y1, abs(dy) as uword +1, color)
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return
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}
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if dy==0 {
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if x1>x2
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x1=x2
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horizontal_line(x1, y1, abs(dx) as uword +1, color)
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return
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}
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word @zp d = 0
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cx16.r1L = true ; 'positive_ix'
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if dx < 0 {
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dx = -dx
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cx16.r1L = false
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}
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word @zp dx2 = dx*2
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word @zp dy2 = dy*2
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cx16.r14 = x1 ; internal plot X
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if dx >= dy {
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if cx16.r1L {
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repeat {
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plot(cx16.r14, y1, color)
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if cx16.r14==x2
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return
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cx16.r14++
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d += dy2
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if d > dx {
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y1++
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d -= dx2
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}
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}
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} else {
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repeat {
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plot(cx16.r14, y1, color)
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if cx16.r14==x2
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return
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cx16.r14--
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d += dy2
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if d > dx {
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y1++
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d -= dx2
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}
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}
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}
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}
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else {
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if cx16.r1L {
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repeat {
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plot(cx16.r14, y1, color)
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if y1 == y2
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return
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y1++
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d += dx2
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if d > dy {
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cx16.r14++
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d -= dy2
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}
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}
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} else {
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repeat {
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plot(cx16.r14, y1, color)
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if y1 == y2
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return
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y1++
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d += dx2
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if d > dy {
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cx16.r14--
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d -= dy2
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}
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}
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}
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}
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}
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sub circle(uword @zp xcenter, uword @zp ycenter, ubyte radius, ubyte color) {
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; Midpoint algorithm.
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if radius==0
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return
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ubyte @zp xx = radius
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ubyte @zp yy = 0
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word @zp decisionOver2 = (1 as word)-xx
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; R14 = internal plot X
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; R15 = internal plot Y
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while xx>=yy {
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cx16.r14 = xcenter + xx
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cx16.r15 = ycenter + yy
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plot(cx16.r14, cx16.r15, color)
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cx16.r14 = xcenter - xx
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plot(cx16.r14, cx16.r15, color)
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cx16.r14 = xcenter + xx
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cx16.r15 = ycenter - yy
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plot(cx16.r14, cx16.r15, color)
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cx16.r14 = xcenter - xx
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plot(cx16.r14, cx16.r15, color)
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cx16.r14 = xcenter + yy
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cx16.r15 = ycenter + xx
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plot(cx16.r14, cx16.r15, color)
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cx16.r14 = xcenter - yy
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plot(cx16.r14, cx16.r15, color)
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cx16.r14 = xcenter + yy
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cx16.r15 = ycenter - xx
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plot(cx16.r14, cx16.r15, color)
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cx16.r14 = xcenter - yy
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plot(cx16.r14, cx16.r15, color)
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yy++
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if decisionOver2<=0
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decisionOver2 += (yy as word)*2+1
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else {
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xx--
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decisionOver2 += (yy as word -xx)*2+1
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}
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}
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}
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sub disc(uword @zp xcenter, uword @zp ycenter, ubyte @zp radius, ubyte color) {
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; Midpoint algorithm, filled
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if radius==0
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return
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ubyte @zp yy = 0
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word @zp decisionOver2 = (1 as word)-radius
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while radius>=yy {
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horizontal_line(xcenter-radius, ycenter+yy, radius*$0002+1, color)
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horizontal_line(xcenter-radius, ycenter-yy, radius*$0002+1, color)
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horizontal_line(xcenter-yy, ycenter+radius, yy*$0002+1, color)
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horizontal_line(xcenter-yy, ycenter-radius, yy*$0002+1, color)
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yy++
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if decisionOver2<=0
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decisionOver2 += (yy as word)*2+1
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else {
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radius--
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decisionOver2 += (yy as word -radius)*2+1
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}
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}
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}
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sub plot(uword @zp xx, uword @zp yy, ubyte @zp color) {
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ubyte[4] @shared mask4c = [%00111111, %11001111, %11110011, %11111100]
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ubyte[4] @shared shift4c = [6,4,2,0]
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ubyte[4] shiftedleft_4c_1 = [1<<6, 1<<4, 1<<2, 1<<0]
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ubyte[4] shiftedleft_4c_2 = [2<<6, 2<<4, 2<<2, 2<<0]
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ubyte[4] shiftedleft_4c_3 = [3<<6, 3<<4, 3<<2, 3<<0]
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when active_mode {
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1 -> {
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; lores 256c
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void addr_mul_24_for_lores_256c(yy, xx) ; 24 bits result is in r0 and r1L (highest byte)
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%asm {{
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stz cx16.VERA_CTRL
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lda cx16.r1
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ora #%00010000 ; enable auto-increment so next_pixel() can be used after this
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sta cx16.VERA_ADDR_H
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lda cx16.r0+1
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sta cx16.VERA_ADDR_M
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lda cx16.r0
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sta cx16.VERA_ADDR_L
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lda color
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sta cx16.VERA_DATA0
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}}
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}
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2 -> {
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; highres 4c ....also mostly usable for lores 4c?
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void addr_mul_24_for_highres_4c(yy, xx) ; 24 bits result is in r0 and r1L (highest byte)
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cx16.r2L = lsb(xx) & 3 ; xbits
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; color &= 3
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; color <<= shift4c[cx16.r2L]
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when color & 3 {
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1 -> color = shiftedleft_4c_1[cx16.r2L]
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2 -> color = shiftedleft_4c_2[cx16.r2L]
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3 -> color = shiftedleft_4c_3[cx16.r2L]
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}
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%asm {{
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stz cx16.VERA_CTRL
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lda cx16.r1L
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sta cx16.VERA_ADDR_H
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lda cx16.r0H
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sta cx16.VERA_ADDR_M
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lda cx16.r0L
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sta cx16.VERA_ADDR_L
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ldy cx16.r2L ; xbits
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lda mask4c,y
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and cx16.VERA_DATA0
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ora color
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sta cx16.VERA_DATA0
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}}
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}
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}
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}
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sub pget(uword @zp xx, uword yy) -> ubyte {
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when active_mode {
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1 -> {
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; lores 256c
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void addr_mul_24_for_lores_256c(yy, xx) ; 24 bits result is in r0 and r1L (highest byte)
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%asm {{
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stz cx16.VERA_CTRL
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lda cx16.r1
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sta cx16.VERA_ADDR_H
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lda cx16.r0+1
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sta cx16.VERA_ADDR_M
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lda cx16.r0
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sta cx16.VERA_ADDR_L
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lda cx16.VERA_DATA0
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}}
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}
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2 -> {
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; hires 4c
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void addr_mul_24_for_highres_4c(yy, xx) ; 24 bits result is in r0 and r1L (highest byte)
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%asm {{
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stz cx16.VERA_CTRL
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lda cx16.r1L
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sta cx16.VERA_ADDR_H
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lda cx16.r0H
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sta cx16.VERA_ADDR_M
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lda cx16.r0L
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sta cx16.VERA_ADDR_L
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lda cx16.VERA_DATA0
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sta cx16.r0L
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}}
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cx16.r1L = lsb(xx) & 3
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cx16.r0L >>= gfx2.plot.shift4c[cx16.r1L]
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return cx16.r0L & 3
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}
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else -> return 0
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}
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}
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sub fill(word @zp xx, word @zp yy, ubyte new_color) {
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; Non-recursive scanline flood fill.
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; based loosely on code found here https://www.codeproject.com/Articles/6017/QuickFill-An-efficient-flood-fill-algorithm
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; with the fixes applied to the seedfill_4 routine as mentioned in the comments.
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const ubyte MAXDEPTH = 48
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word[MAXDEPTH] @split @shared stack_xl
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word[MAXDEPTH] @split @shared stack_xr
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word[MAXDEPTH] @split @shared stack_y
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byte[MAXDEPTH] @shared stack_dy
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cx16.r12L = 0 ; stack pointer
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word x1
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word x2
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byte dy
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cx16.r10L = new_color
|
|
sub push_stack(word sxl, word sxr, word sy, byte sdy) {
|
|
if cx16.r12L==MAXDEPTH
|
|
return
|
|
cx16.r0s = sy+sdy
|
|
if cx16.r0s>=0 and cx16.r0s<=height-1 {
|
|
;; stack_xl[cx16.r12L] = sxl
|
|
;; stack_xr[cx16.r12L] = sxr
|
|
;; stack_y[cx16.r12L] = sy
|
|
;; stack_dy[cx16.r12L] = sdy
|
|
;; cx16.r12L++
|
|
%asm {{
|
|
ldy cx16.r12L
|
|
lda sxl
|
|
sta stack_xl_lsb,y
|
|
lda sxl+1
|
|
sta stack_xl_msb,y
|
|
lda sxr
|
|
sta stack_xr_lsb,y
|
|
lda sxr+1
|
|
sta stack_xr_msb,y
|
|
lda sy
|
|
sta stack_y_lsb,y
|
|
lda sy+1
|
|
sta stack_y_msb,y
|
|
ldy cx16.r12L
|
|
lda sdy
|
|
sta stack_dy,y
|
|
inc cx16.r12L
|
|
}}
|
|
}
|
|
}
|
|
sub pop_stack() {
|
|
;; cx16.r12L--
|
|
;; x1 = stack_xl[cx16.r12L]
|
|
;; x2 = stack_xr[cx16.r12L]
|
|
;; y = stack_y[cx16.r12L]
|
|
;; dy = stack_dy[cx16.r12L]
|
|
%asm {{
|
|
dec cx16.r12L
|
|
ldy cx16.r12L
|
|
lda stack_xl_lsb,y
|
|
sta x1
|
|
lda stack_xl_msb,y
|
|
sta x1+1
|
|
lda stack_xr_lsb,y
|
|
sta x2
|
|
lda stack_xr_msb,y
|
|
sta x2+1
|
|
lda stack_y_lsb,y
|
|
sta yy
|
|
lda stack_y_msb,y
|
|
sta yy+1
|
|
ldy cx16.r12L
|
|
lda stack_dy,y
|
|
sta dy
|
|
}}
|
|
yy+=dy
|
|
}
|
|
cx16.r11L = pget(xx as uword, yy as uword) ; old_color
|
|
if cx16.r11L == cx16.r10L
|
|
return
|
|
if xx<0 or xx>width-1 or yy<0 or yy>height-1
|
|
return
|
|
push_stack(xx, xx, yy, 1)
|
|
push_stack(xx, xx, yy + 1, -1)
|
|
word left = 0
|
|
while cx16.r12L {
|
|
pop_stack()
|
|
xx = x1
|
|
while xx >= 0 and pget(xx as uword, yy as uword) == cx16.r11L {
|
|
plot(xx as uword, yy as uword, cx16.r10L)
|
|
xx--
|
|
}
|
|
if xx >= x1
|
|
goto skip
|
|
|
|
left = xx + 1
|
|
if left < x1
|
|
push_stack(left, x1 - 1, yy, -dy)
|
|
xx = x1 + 1
|
|
|
|
do {
|
|
while xx <= width-1 and pget(xx as uword, yy as uword) == cx16.r11L {
|
|
plot(xx as uword, yy as uword, cx16.r10L)
|
|
xx++
|
|
}
|
|
push_stack(left, xx - 1, yy, dy)
|
|
if xx > x2 + 1
|
|
push_stack(x2 + 1, xx - 1, yy, -dy)
|
|
skip:
|
|
xx++
|
|
while xx <= x2 and pget(xx as uword, yy as uword) != cx16.r11L
|
|
xx++
|
|
left = xx
|
|
} until xx>x2
|
|
}
|
|
}
|
|
|
|
sub position(uword @zp xx, uword yy) {
|
|
when active_mode {
|
|
1 -> {
|
|
; lores 256c
|
|
void addr_mul_24_for_lores_256c(yy, xx) ; 24 bits result is in r0 and r1L (highest byte)
|
|
}
|
|
2 -> {
|
|
; highres 4c
|
|
void addr_mul_24_for_highres_4c(yy, xx) ; 24 bits result is in r0 and r1L (highest byte)
|
|
}
|
|
}
|
|
cx16.r2L = cx16.r1L
|
|
cx16.vaddr(cx16.r2L, cx16.r0, 0, 1)
|
|
}
|
|
|
|
sub position2(uword @zp xx, uword yy, bool also_port_1) {
|
|
position(xx, yy)
|
|
if also_port_1
|
|
cx16.vaddr_clone(0)
|
|
}
|
|
|
|
inline asmsub next_pixel(ubyte color @A) {
|
|
; -- sets the next pixel byte to the graphics chip.
|
|
; for 8 bpp screens this will plot 1 pixel.
|
|
; for 2 bpp screens it will plot 4 pixels at once (color = bit pattern).
|
|
%asm {{
|
|
sta cx16.VERA_DATA0
|
|
}}
|
|
}
|
|
|
|
asmsub next_pixels(uword pixels @AY, uword amount @R0) clobbers(A, X, Y) {
|
|
; -- sets the next bunch of pixels from a prepared array of bytes.
|
|
; for 8 bpp screens this will plot 1 pixel per byte.
|
|
; for 2 bpp screens it will plot 4 pixels at once (colors are the bit patterns per byte).
|
|
%asm {{
|
|
sta P8ZP_SCRATCH_W1
|
|
sty P8ZP_SCRATCH_W1+1
|
|
ldx cx16.r0+1
|
|
beq +
|
|
ldy #0
|
|
- lda (P8ZP_SCRATCH_W1),y
|
|
sta cx16.VERA_DATA0
|
|
iny
|
|
bne -
|
|
inc P8ZP_SCRATCH_W1+1 ; next page of 256 pixels
|
|
dex
|
|
bne -
|
|
|
|
+ ldx cx16.r0 ; remaining pixels
|
|
beq +
|
|
ldy #0
|
|
- lda (P8ZP_SCRATCH_W1),y
|
|
sta cx16.VERA_DATA0
|
|
iny
|
|
dex
|
|
bne -
|
|
+ rts
|
|
}}
|
|
}
|
|
|
|
asmsub set_8_pixels_from_bits(ubyte bits @R0, ubyte oncolor @A, ubyte offcolor @Y) clobbers(X) {
|
|
; this is only useful in 256 color mode where one pixel equals one byte value.
|
|
%asm {{
|
|
ldx #8
|
|
- asl cx16.r0
|
|
bcc +
|
|
sta cx16.VERA_DATA0
|
|
bra ++
|
|
+ sty cx16.VERA_DATA0
|
|
+ dex
|
|
bne -
|
|
rts
|
|
}}
|
|
}
|
|
|
|
const ubyte charset_bank = $1
|
|
const uword charset_addr = $f000 ; in bank 1, so $1f000
|
|
|
|
sub text_charset(ubyte charset) {
|
|
; -- select the text charset to use with the text() routine
|
|
; the charset number is the same as for the cx16.screen_set_charset() ROM function.
|
|
; 1 = ISO charset, 2 = PETSCII uppercase+graphs, 3= PETSCII uppercase+lowercase.
|
|
cx16.screen_set_charset(charset, 0)
|
|
}
|
|
|
|
sub text(uword @zp xx, uword yy, ubyte color, uword sctextptr) {
|
|
; -- Write some text at the given pixel position. The text string must be in screencode encoding (not petscii!).
|
|
; You must also have called text_charset() first to select and prepare the character set to use.
|
|
uword chardataptr
|
|
ubyte[8] @shared char_bitmap_bytes_left
|
|
ubyte[8] @shared char_bitmap_bytes_right
|
|
|
|
when active_mode {
|
|
1 -> {
|
|
; lores 256c
|
|
while @(sctextptr) {
|
|
chardataptr = charset_addr + (@(sctextptr) as uword)*8
|
|
cx16.vaddr(charset_bank, chardataptr, 1, 1)
|
|
repeat 8 {
|
|
position(xx,yy)
|
|
yy++
|
|
%asm {{
|
|
ldx color
|
|
lda cx16.VERA_DATA1
|
|
sta P8ZP_SCRATCH_B1
|
|
ldy #8
|
|
- asl P8ZP_SCRATCH_B1
|
|
bcc +
|
|
stx cx16.VERA_DATA0 ; write a pixel
|
|
bra ++
|
|
+ lda cx16.VERA_DATA0 ; don't write a pixel, but do advance to the next address
|
|
+ dey
|
|
bne -
|
|
}}
|
|
}
|
|
xx+=8
|
|
yy-=8
|
|
sctextptr++
|
|
}
|
|
}
|
|
2 -> {
|
|
; hires 4c
|
|
; we're going to use a few cx16 registers to make sure every variable is in zeropage in the inner loop.
|
|
cx16.r11L = color
|
|
while @(sctextptr) {
|
|
chardataptr = charset_addr + (@(sctextptr) as uword)*8
|
|
cx16.vaddr(charset_bank, chardataptr, 1, true) ; for reading the chardata from Vera data channel 1
|
|
position(xx, yy) ; only calculated once, we update vera address in the loop instead
|
|
cx16.VERA_ADDR_H &= $0f ; no auto increment
|
|
repeat 8 {
|
|
cx16.r10L = cx16.VERA_DATA1 ; get the next 8 horizontal character bits
|
|
cx16.r7 = xx
|
|
repeat 8 {
|
|
cx16.r10L <<= 1
|
|
if_cs {
|
|
cx16.r2L = cx16.r7L & 3 ; xbits
|
|
when cx16.r11L & 3 {
|
|
1 -> cx16.r12L = gfx2.plot.shiftedleft_4c_1[cx16.r2L]
|
|
2 -> cx16.r12L = gfx2.plot.shiftedleft_4c_2[cx16.r2L]
|
|
3 -> cx16.r12L = gfx2.plot.shiftedleft_4c_3[cx16.r2L]
|
|
else -> cx16.r12L = 0
|
|
}
|
|
cx16.VERA_DATA0 = cx16.VERA_DATA0 & gfx2.plot.mask4c[cx16.r2L] | cx16.r12L
|
|
}
|
|
cx16.r7++
|
|
if (cx16.r7 & 3) == 0 {
|
|
; increment the pixel address by one
|
|
%asm {{
|
|
stz cx16.VERA_CTRL
|
|
clc
|
|
lda cx16.VERA_ADDR_L
|
|
adc #1
|
|
sta cx16.VERA_ADDR_L
|
|
lda cx16.VERA_ADDR_M
|
|
adc #0
|
|
sta cx16.VERA_ADDR_M
|
|
lda cx16.VERA_ADDR_H
|
|
adc #0
|
|
sta cx16.VERA_ADDR_H
|
|
}}
|
|
}
|
|
}
|
|
|
|
; increment pixel address to the next line
|
|
%asm {{
|
|
stz cx16.VERA_CTRL
|
|
clc
|
|
lda cx16.VERA_ADDR_L
|
|
adc #(640-8)/4
|
|
sta cx16.VERA_ADDR_L
|
|
lda cx16.VERA_ADDR_M
|
|
adc #0
|
|
sta cx16.VERA_ADDR_M
|
|
lda cx16.VERA_ADDR_H
|
|
adc #0
|
|
sta cx16.VERA_ADDR_H
|
|
}}
|
|
}
|
|
xx+=8
|
|
sctextptr++
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
asmsub cs_innerloop640() clobbers(Y) {
|
|
%asm {{
|
|
ldy #80
|
|
- stz cx16.VERA_DATA0
|
|
stz cx16.VERA_DATA0
|
|
stz cx16.VERA_DATA0
|
|
stz cx16.VERA_DATA0
|
|
stz cx16.VERA_DATA0
|
|
stz cx16.VERA_DATA0
|
|
stz cx16.VERA_DATA0
|
|
stz cx16.VERA_DATA0
|
|
dey
|
|
bne -
|
|
rts
|
|
}}
|
|
}
|
|
|
|
asmsub addr_mul_24_for_highres_4c(uword yy @R2, uword xx @R3) clobbers(A, Y) -> uword @R0, uword @R1 {
|
|
; yy * 160 + xx/4 (24 bits calculation)
|
|
; 24 bits result is in r0 and r1L (highest byte)
|
|
%asm {{
|
|
ldy #5
|
|
- asl cx16.r2
|
|
rol cx16.r2+1
|
|
dey
|
|
bne -
|
|
lda cx16.r2
|
|
sta cx16.r0
|
|
lda cx16.r2+1
|
|
sta cx16.r0+1
|
|
asl cx16.r0
|
|
rol cx16.r0+1
|
|
asl cx16.r0
|
|
rol cx16.r0+1
|
|
|
|
; xx >>= 2 (xx=R3)
|
|
lsr cx16.r3+1
|
|
ror cx16.r3
|
|
lsr cx16.r3+1
|
|
ror cx16.r3
|
|
|
|
; add r2 and xx (r3) to r0 (24-bits)
|
|
stz cx16.r1
|
|
clc
|
|
lda cx16.r0
|
|
adc cx16.r2
|
|
sta cx16.r0
|
|
lda cx16.r0+1
|
|
adc cx16.r2+1
|
|
sta cx16.r0+1
|
|
bcc +
|
|
inc cx16.r1
|
|
+ clc
|
|
lda cx16.r0
|
|
adc cx16.r3
|
|
sta cx16.r0
|
|
lda cx16.r0+1
|
|
adc cx16.r3+1
|
|
sta cx16.r0+1
|
|
bcc +
|
|
inc cx16.r1
|
|
+
|
|
rts
|
|
}}
|
|
}
|
|
|
|
asmsub addr_mul_24_for_lores_256c(uword yy @R0, uword xx @AY) clobbers(A) -> uword @R0, ubyte @R1 {
|
|
; yy * 320 + xx (24 bits calculation)
|
|
%asm {{
|
|
sta P8ZP_SCRATCH_W1
|
|
sty P8ZP_SCRATCH_W1+1
|
|
lda cx16.r0
|
|
sta P8ZP_SCRATCH_B1
|
|
lda cx16.r0+1
|
|
sta cx16.r1
|
|
sta P8ZP_SCRATCH_REG
|
|
lda cx16.r0
|
|
asl a
|
|
rol P8ZP_SCRATCH_REG
|
|
asl a
|
|
rol P8ZP_SCRATCH_REG
|
|
asl a
|
|
rol P8ZP_SCRATCH_REG
|
|
asl a
|
|
rol P8ZP_SCRATCH_REG
|
|
asl a
|
|
rol P8ZP_SCRATCH_REG
|
|
asl a
|
|
rol P8ZP_SCRATCH_REG
|
|
sta cx16.r0
|
|
lda P8ZP_SCRATCH_B1
|
|
clc
|
|
adc P8ZP_SCRATCH_REG
|
|
sta cx16.r0+1
|
|
bcc +
|
|
inc cx16.r1
|
|
+ ; now add the value to this 24-bits number
|
|
lda cx16.r0
|
|
clc
|
|
adc P8ZP_SCRATCH_W1
|
|
sta cx16.r0
|
|
lda cx16.r0+1
|
|
adc P8ZP_SCRATCH_W1+1
|
|
sta cx16.r0+1
|
|
bcc +
|
|
inc cx16.r1
|
|
+ lda cx16.r1
|
|
rts
|
|
}}
|
|
}
|
|
|
|
}
|