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.
785 lines
24 KiB
Lua
785 lines
24 KiB
Lua
; Monochrome Bitmap pixel graphics routines for the CommanderX16
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; Using the full-screen 640x480 and 320x240 screen modes, in 1 bpp mode (black/white).
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;
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; No text layer is currently shown, but text can be drawn as part of the bitmap itself.
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; For color bitmap graphics, see the gfx2 library.
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;
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; NOTE: a lot of the code here is similar or the same to that in gfx2
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monogfx {
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%option no_symbol_prefixing
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; read-only control variables:
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uword width = 0
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uword height = 0
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bool dont_stipple_flag = true ; set to false to enable stippling mode
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sub lores() {
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; enable 320*240 bitmap mode
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cx16.VERA_CTRL=0
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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 = %00000100
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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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clear_screen()
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}
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sub hires() {
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; enable 640*480 bitmap mode
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cx16.VERA_CTRL=0
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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 = %00000100
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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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clear_screen()
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}
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sub textmode() {
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; back to normal 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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}
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sub clear_screen() {
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stipple(false)
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position(0, 0)
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when width {
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320 -> {
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repeat 240/2/8
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cs_innerloop640()
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}
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640 -> {
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repeat 480/8
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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 stipple(bool enable) {
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dont_stipple_flag = not enable
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}
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sub rect(uword xx, uword yy, uword rwidth, uword rheight, bool draw) {
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if rwidth==0 or rheight==0
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return
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horizontal_line(xx, yy, rwidth, draw)
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if rheight==1
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return
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horizontal_line(xx, yy+rheight-1, rwidth, draw)
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vertical_line(xx, yy+1, rheight-2, draw)
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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, draw)
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}
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sub fillrect(uword xx, uword yy, uword rwidth, uword rheight, bool draw) {
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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, draw)
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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, bool draw) {
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ubyte[9] masked_starts = [ 0, %00000001, %00000011, %00000111, %00001111, %00011111, %00111111, %01111111, %11111111]
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ubyte[9] masked_ends = [ 0, %10000000, %11000000, %11100000, %11110000, %11111000, %11111100, %11111110, %11111111]
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if length==0
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return
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if length<=8 {
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; just use 2 byte writes with shifted mask
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position2(xx,yy,true)
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%asm {{
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ldy length
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lda masked_ends,y
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sta cx16.r0L ; save left byte
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stz P8ZP_SCRATCH_B1
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lda xx
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and #7
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beq +
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tay
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lda cx16.r0L
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- lsr a
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ror P8ZP_SCRATCH_B1
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dey
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bne -
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sta cx16.r0L ; new left byte
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+
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lda dont_stipple_flag
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bne _dontstipple
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; determine stipple pattern
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lda yy
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and #1
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beq +
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lda #%10101010
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bne ++
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+ lda #%01010101
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+ sta P8ZP_SCRATCH_REG
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lda cx16.r0L
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and P8ZP_SCRATCH_REG
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sta cx16.r0L
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lda P8ZP_SCRATCH_B1
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and P8ZP_SCRATCH_REG
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sta P8ZP_SCRATCH_B1
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_dontstipple
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lda draw
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beq _clear
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lda cx16.r0L ; left byte
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ora cx16.VERA_DATA1
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sta cx16.VERA_DATA0
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lda P8ZP_SCRATCH_B1 ; right byte
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ora cx16.VERA_DATA1
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sta cx16.VERA_DATA0
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rts
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_clear
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lda cx16.r0L ; left byte
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eor #255
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and cx16.VERA_DATA1
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sta cx16.VERA_DATA0
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lda P8ZP_SCRATCH_B1 ; right byte
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eor #255
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and cx16.VERA_DATA1
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sta cx16.VERA_DATA0
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rts
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}}
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}
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ubyte separate_pixels = (8-lsb(xx)) & 7
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if separate_pixels {
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if dont_stipple_flag {
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position(xx,yy)
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cx16.VERA_ADDR_H &= %00000111 ; vera auto-increment off
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if draw
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cx16.VERA_DATA0 |= masked_starts[separate_pixels]
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else
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cx16.VERA_DATA0 &= ~masked_starts[separate_pixels]
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xx += separate_pixels
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} else {
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repeat separate_pixels {
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plot(xx, yy, draw)
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xx++
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}
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}
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length -= separate_pixels
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}
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if length {
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position(xx, yy)
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separate_pixels = lsb(length) & 7
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xx += length & $fff8
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%asm {{
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lsr length+1
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ror length
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lsr length+1
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ror length
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lsr length+1
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ror length
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lda draw
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bne +
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ldy #0 ; black
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bra _loop
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+ lda dont_stipple_flag
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beq _stipple
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ldy #255 ; don't stipple
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bra _loop
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_stipple lda yy
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and #1 ; determine stipple pattern to use
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bne +
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ldy #%01010101
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bra _loop
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+ ldy #%10101010
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_loop lda length
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ora length+1
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beq _done
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sty cx16.VERA_DATA0
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lda length
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bne +
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dec length+1
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+ dec length
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bra _loop
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_done
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}}
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if dont_stipple_flag {
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cx16.VERA_ADDR_H &= %00000111 ; vera auto-increment off
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if draw
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cx16.VERA_DATA0 |= masked_ends[separate_pixels]
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else
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cx16.VERA_DATA0 &= ~masked_ends[separate_pixels]
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} else {
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repeat separate_pixels {
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plot(xx, yy, draw)
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xx++
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}
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}
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}
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cx16.VERA_ADDR_H &= %00000111 ; vera auto-increment off again
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}
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sub vertical_line(uword xx, uword yy, uword lheight, bool draw) {
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cx16.r15L = monogfx.plot.maskbits[xx as ubyte & 7] ; bitmask
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if draw {
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if dont_stipple_flag {
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; draw continuous line.
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position2(xx,yy,true)
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if width==320
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set_both_strides(11) ; 40 increment = 1 line in 320 px monochrome
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else
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set_both_strides(12) ; 80 increment = 1 line in 640 px monochrome
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repeat lheight {
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%asm {{
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lda cx16.VERA_DATA0
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ora cx16.r15L
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sta cx16.VERA_DATA1
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}}
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}
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} else {
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; draw stippled line.
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if (xx ^ yy)&1==0 {
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yy++
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lheight--
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}
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lheight++ ; because it is divided by 2 later, don't round off the last pixel
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position2(xx,yy,true)
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if width==320
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set_both_strides(12) ; 80 increment = 2 line in 320 px monochrome
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else
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set_both_strides(13) ; 160 increment = 2 line in 640 px monochrome
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repeat lheight/2 {
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%asm {{
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lda cx16.VERA_DATA0
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ora cx16.r15L
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sta cx16.VERA_DATA1
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}}
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}
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}
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} else {
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position2(xx,yy,true)
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cx16.r15 = ~cx16.r15 ; erase pixels
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if width==320
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set_both_strides(11) ; 40 increment = 1 line in 320 px monochrome
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else
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set_both_strides(12) ; 80 increment = 1 line in 640 px monochrome
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repeat lheight {
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%asm {{
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lda cx16.VERA_DATA0
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and cx16.r15L
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sta cx16.VERA_DATA1
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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, bool draw) {
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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, draw)
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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, draw)
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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, draw)
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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, draw)
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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, draw)
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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, draw)
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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, bool draw) {
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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, draw)
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cx16.r14 = xcenter - xx
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plot(cx16.r14, cx16.r15, draw)
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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, draw)
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cx16.r14 = xcenter - xx
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plot(cx16.r14, cx16.r15, draw)
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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, draw)
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cx16.r14 = xcenter - yy
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plot(cx16.r14, cx16.r15, draw)
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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, draw)
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cx16.r14 = xcenter - yy
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plot(cx16.r14, cx16.r15, draw)
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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, bool draw) {
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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, draw)
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horizontal_line(xcenter-radius, ycenter-yy, radius*$0002+1, draw)
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horizontal_line(xcenter-yy, ycenter+radius, yy*$0002+1, draw)
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horizontal_line(xcenter-yy, ycenter-radius, yy*$0002+1, draw)
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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, bool @zp draw) {
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ubyte[8] @shared maskbits = [128, 64, 32, 16, 8, 4, 2, 1]
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if draw {
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; solid color or perhaps stipple
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%asm {{
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lda xx
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eor yy
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ora dont_stipple_flag
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and #1
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}}
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if_nz {
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prepare()
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%asm {{
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tsb cx16.VERA_DATA0
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}}
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}
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} else {
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; only erase
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prepare()
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%asm {{
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trb cx16.VERA_DATA0
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}}
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}
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sub prepare() {
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%asm {{
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lda xx
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and #7
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pha ; xbits
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}}
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xx /= 8
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if width==320
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xx += yy*(320/8)
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else
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xx += yy*(640/8)
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%asm {{
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stz cx16.VERA_CTRL
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stz cx16.VERA_ADDR_H
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lda xx+1
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sta cx16.VERA_ADDR_M
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lda xx
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sta cx16.VERA_ADDR_L
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ply ; xbits
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lda maskbits,y
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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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%asm {{
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lda xx
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and #7
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pha ; xbits
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}}
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xx /= 8
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if width==320
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xx += yy*(320/8)
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else
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xx += yy*(640/8)
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%asm {{
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stz cx16.VERA_CTRL
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stz cx16.VERA_ADDR_H
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lda xx+1
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sta cx16.VERA_ADDR_M
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lda xx
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sta cx16.VERA_ADDR_L
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ply ; xbits
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lda plot.maskbits,y
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and cx16.VERA_DATA0
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beq +
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lda #1
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+ rts
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}}
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}
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sub fill(word @zp xx, word @zp yy, bool draw) {
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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
|
|
byte dy
|
|
cx16.r10L = draw as ubyte
|
|
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) {
|
|
if width==320
|
|
cx16.r0 = yy*(320/8)
|
|
else
|
|
cx16.r0 = yy*(640/8)
|
|
cx16.vaddr(0, cx16.r0+(xx/8), 0, 1)
|
|
}
|
|
|
|
sub position2(uword @zp xx, uword yy, bool also_port_1) {
|
|
position(xx, yy)
|
|
if also_port_1
|
|
cx16.vaddr_clone(0)
|
|
}
|
|
|
|
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, bool draw, 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
|
|
|
|
cx16.r3 = sctextptr
|
|
while @(cx16.r3) {
|
|
chardataptr = charset_addr + @(cx16.r3) * $0008
|
|
; copy the character bitmap into RAM
|
|
cx16.vaddr_autoincr(charset_bank, chardataptr, 0, 1)
|
|
%asm {{
|
|
; pre-shift the bits
|
|
lda text.xx
|
|
and #7
|
|
sta P8ZP_SCRATCH_B1
|
|
ldy #0
|
|
- lda cx16.VERA_DATA0
|
|
stz P8ZP_SCRATCH_REG
|
|
ldx P8ZP_SCRATCH_B1
|
|
cpx #0
|
|
beq +
|
|
- lsr a
|
|
ror P8ZP_SCRATCH_REG
|
|
dex
|
|
bne -
|
|
+ sta char_bitmap_bytes_left,y
|
|
lda P8ZP_SCRATCH_REG
|
|
sta char_bitmap_bytes_right,y
|
|
iny
|
|
cpy #8
|
|
bne --
|
|
}}
|
|
; left part of shifted char
|
|
position2(xx, yy, true)
|
|
set_autoincrs()
|
|
if draw {
|
|
%asm {{
|
|
ldy #0
|
|
- lda char_bitmap_bytes_left,y
|
|
ora cx16.VERA_DATA1
|
|
sta cx16.VERA_DATA0
|
|
iny
|
|
cpy #8
|
|
bne -
|
|
}}
|
|
} else {
|
|
%asm {{
|
|
ldy #0
|
|
- lda char_bitmap_bytes_left,y
|
|
eor #255
|
|
and cx16.VERA_DATA1
|
|
sta cx16.VERA_DATA0
|
|
iny
|
|
cpy #8
|
|
bne -
|
|
}}
|
|
}
|
|
; right part of shifted char
|
|
if lsb(xx) & 7 {
|
|
position2(xx+8, yy, true)
|
|
set_autoincrs()
|
|
if draw {
|
|
%asm {{
|
|
ldy #0
|
|
- lda char_bitmap_bytes_right,y
|
|
ora cx16.VERA_DATA1
|
|
sta cx16.VERA_DATA0
|
|
iny
|
|
cpy #8
|
|
bne -
|
|
}}
|
|
} else {
|
|
%asm {{
|
|
ldy #0
|
|
- lda char_bitmap_bytes_right,y
|
|
eor #255
|
|
and cx16.VERA_DATA1
|
|
sta cx16.VERA_DATA0
|
|
iny
|
|
cpy #8
|
|
bne -
|
|
}}
|
|
}
|
|
}
|
|
cx16.r3++
|
|
xx += 8
|
|
}
|
|
|
|
sub set_autoincrs() {
|
|
; set autoincrements to go to next pixel row (40 or 80 increment)
|
|
if width==320 {
|
|
cx16.VERA_CTRL = 0
|
|
cx16.VERA_ADDR_H = cx16.VERA_ADDR_H & $0f | (11<<4)
|
|
cx16.VERA_CTRL = 1
|
|
cx16.VERA_ADDR_H = cx16.VERA_ADDR_H & $0f | (11<<4)
|
|
} else {
|
|
cx16.VERA_CTRL = 0
|
|
cx16.VERA_ADDR_H = cx16.VERA_ADDR_H & $0f | (12<<4)
|
|
cx16.VERA_CTRL = 1
|
|
cx16.VERA_ADDR_H = cx16.VERA_ADDR_H & $0f | (12<<4)
|
|
}
|
|
}
|
|
}
|
|
|
|
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
|
|
}}
|
|
}
|
|
}
|