mirror of
https://github.com/irmen/prog8.git
synced 2024-12-25 23:29:55 +00:00
466 lines
14 KiB
Lua
466 lines
14 KiB
Lua
; Monochrome Bitmap pixel graphics routines for the Virtual Machine
|
|
; Using the full-screen 640x480 and 320x240 screen modes, but just black/white.
|
|
;
|
|
; NOTE: For sake of speed, NO BOUNDS CHECKING is performed in most routines!
|
|
; You'll have to make sure yourself that you're not writing outside of bitmap boundaries!
|
|
|
|
|
|
monogfx {
|
|
|
|
%option ignore_unused
|
|
|
|
; read-only control variables:
|
|
uword width = 0
|
|
uword height = 0
|
|
bool dont_stipple_flag = true ; set to false to enable stippling mode
|
|
|
|
sub lores() {
|
|
; enable 320*240 bitmap mode
|
|
sys.gfx_enable(0)
|
|
width = 320
|
|
height = 240
|
|
clear_screen(0)
|
|
}
|
|
|
|
sub hires() {
|
|
; enable 640*480 bitmap mode
|
|
sys.gfx_enable(1)
|
|
width = 640
|
|
height = 480
|
|
clear_screen(0)
|
|
}
|
|
|
|
sub textmode() {
|
|
; back to normal text mode
|
|
}
|
|
|
|
sub clear_screen(ubyte color) {
|
|
stipple(false)
|
|
if color
|
|
color=255
|
|
sys.gfx_clear(color)
|
|
}
|
|
|
|
sub stipple(bool enable) {
|
|
dont_stipple_flag = not enable
|
|
}
|
|
|
|
sub rect(uword xx, uword yy, uword rwidth, uword rheight, bool draw) {
|
|
if rwidth==0 or rheight==0
|
|
return
|
|
horizontal_line(xx, yy, rwidth, draw)
|
|
if rheight==1
|
|
return
|
|
horizontal_line(xx, yy+rheight-1, rwidth, draw)
|
|
vertical_line(xx, yy+1, rheight-2, draw)
|
|
if rwidth==1
|
|
return
|
|
vertical_line(xx+rwidth-1, yy+1, rheight-2, draw)
|
|
}
|
|
|
|
sub fillrect(uword xx, uword yy, uword rwidth, uword rheight, bool draw) {
|
|
; Draw a filled rectangle of the given size and color.
|
|
; To fill the whole screen, use clear_screen(color) instead - it is much faster.
|
|
if rwidth==0
|
|
return
|
|
repeat rheight {
|
|
horizontal_line(xx, yy, rwidth, draw)
|
|
yy++
|
|
}
|
|
}
|
|
|
|
sub horizontal_line(uword xx, uword yy, uword length, bool draw) {
|
|
uword xpos
|
|
for xpos in xx to xx+length-1
|
|
plot(xpos, yy, draw)
|
|
}
|
|
|
|
sub safe_horizontal_line(uword xx, uword yy, uword length, bool draw) {
|
|
; does bounds checking and clipping
|
|
if msb(yy)&$80!=0 or yy>=height
|
|
return
|
|
if msb(xx)&$80!=0 {
|
|
length += xx
|
|
xx = 0
|
|
}
|
|
if xx>=width
|
|
return
|
|
if xx+length>width
|
|
length = width-xx
|
|
if length>width
|
|
return
|
|
|
|
horizontal_line(xx, yy, length, draw)
|
|
}
|
|
|
|
sub vertical_line(uword xx, uword yy, uword lheight, bool draw) {
|
|
uword ypos
|
|
for ypos in yy to yy+lheight-1
|
|
plot(xx, ypos, draw)
|
|
}
|
|
|
|
sub line(uword @zp x1, uword @zp y1, uword @zp x2, uword @zp y2, bool draw) {
|
|
; Bresenham algorithm.
|
|
; This code special-cases various quadrant loops to allow simple ++ and -- operations.
|
|
if y1>y2 {
|
|
; make sure dy is always positive to have only 4 instead of 8 special cases
|
|
cx16.r0 = x1
|
|
x1 = x2
|
|
x2 = cx16.r0
|
|
cx16.r0 = y1
|
|
y1 = y2
|
|
y2 = cx16.r0
|
|
}
|
|
word @zp dx = (x2 as word)-x1
|
|
word @zp dy = (y2 as word)-y1
|
|
|
|
if dx==0 {
|
|
vertical_line(x1, y1, abs(dy) as uword +1, draw)
|
|
return
|
|
}
|
|
if dy==0 {
|
|
if x1>x2
|
|
x1=x2
|
|
horizontal_line(x1, y1, abs(dx) as uword +1, draw)
|
|
return
|
|
}
|
|
|
|
word @zp d = 0
|
|
cx16.r1L = true ; 'positive_ix'
|
|
if dx < 0 {
|
|
dx = -dx
|
|
cx16.r1L = false
|
|
}
|
|
word @zp dx2 = dx*2
|
|
word @zp dy2 = dy*2
|
|
cx16.r14 = x1 ; internal plot X
|
|
|
|
if dx >= dy {
|
|
if cx16.r1L {
|
|
repeat {
|
|
plot(cx16.r14, y1, draw)
|
|
if cx16.r14==x2
|
|
return
|
|
cx16.r14++
|
|
d += dy2
|
|
if d > dx {
|
|
y1++
|
|
d -= dx2
|
|
}
|
|
}
|
|
} else {
|
|
repeat {
|
|
plot(cx16.r14, y1, draw)
|
|
if cx16.r14==x2
|
|
return
|
|
cx16.r14--
|
|
d += dy2
|
|
if d > dx {
|
|
y1++
|
|
d -= dx2
|
|
}
|
|
}
|
|
}
|
|
}
|
|
else {
|
|
if cx16.r1L {
|
|
repeat {
|
|
plot(cx16.r14, y1, draw)
|
|
if y1 == y2
|
|
return
|
|
y1++
|
|
d += dx2
|
|
if d > dy {
|
|
cx16.r14++
|
|
d -= dy2
|
|
}
|
|
}
|
|
} else {
|
|
repeat {
|
|
plot(cx16.r14, y1, draw)
|
|
if y1 == y2
|
|
return
|
|
y1++
|
|
d += dx2
|
|
if d > dy {
|
|
cx16.r14--
|
|
d -= dy2
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
sub circle(uword @zp xcenter, uword @zp ycenter, ubyte radius, bool draw) {
|
|
; Warning: NO BOUNDS CHECKS. Make sure circle fits in the screen.
|
|
; Midpoint algorithm.
|
|
if radius==0
|
|
return
|
|
|
|
ubyte @zp xx = radius
|
|
ubyte @zp yy = 0
|
|
word @zp decisionOver2 = (1 as word)-xx
|
|
; R14 = internal plot X
|
|
; R15 = internal plot Y
|
|
|
|
while xx>=yy {
|
|
cx16.r14 = xcenter + xx
|
|
cx16.r15 = ycenter + yy
|
|
plotq()
|
|
cx16.r14 = xcenter - xx
|
|
plotq()
|
|
cx16.r14 = xcenter + xx
|
|
cx16.r15 = ycenter - yy
|
|
plotq()
|
|
cx16.r14 = xcenter - xx
|
|
plotq()
|
|
cx16.r14 = xcenter + yy
|
|
cx16.r15 = ycenter + xx
|
|
plotq()
|
|
cx16.r14 = xcenter - yy
|
|
plotq()
|
|
cx16.r14 = xcenter + yy
|
|
cx16.r15 = ycenter - xx
|
|
plotq()
|
|
cx16.r14 = xcenter - yy
|
|
plotq()
|
|
|
|
yy++
|
|
if decisionOver2>=0 {
|
|
xx--
|
|
decisionOver2 -= xx*$0002
|
|
}
|
|
decisionOver2 += yy*$0002
|
|
decisionOver2++
|
|
}
|
|
|
|
sub plotq() {
|
|
; cx16.r14 = x, cx16.r15 = y, draw=draw
|
|
plot(cx16.r14, cx16.r15, draw)
|
|
}
|
|
}
|
|
|
|
sub safe_circle(uword @zp xcenter, uword @zp ycenter, ubyte radius, bool draw) {
|
|
; Does bounds checking and clipping.
|
|
; Midpoint algorithm.
|
|
if radius==0
|
|
return
|
|
|
|
ubyte @zp xx = radius
|
|
ubyte @zp yy = 0
|
|
word @zp decisionOver2 = (1 as word)-xx
|
|
; R14 = internal plot X
|
|
; R15 = internal plot Y
|
|
|
|
while xx>=yy {
|
|
cx16.r14 = xcenter + xx
|
|
cx16.r15 = ycenter + yy
|
|
plotq()
|
|
cx16.r14 = xcenter - xx
|
|
plotq()
|
|
cx16.r14 = xcenter + xx
|
|
cx16.r15 = ycenter - yy
|
|
plotq()
|
|
cx16.r14 = xcenter - xx
|
|
plotq()
|
|
cx16.r14 = xcenter + yy
|
|
cx16.r15 = ycenter + xx
|
|
plotq()
|
|
cx16.r14 = xcenter - yy
|
|
plotq()
|
|
cx16.r14 = xcenter + yy
|
|
cx16.r15 = ycenter - xx
|
|
plotq()
|
|
cx16.r14 = xcenter - yy
|
|
plotq()
|
|
|
|
yy++
|
|
if decisionOver2>=0 {
|
|
xx--
|
|
decisionOver2 -= xx*$0002
|
|
}
|
|
decisionOver2 += yy*$0002
|
|
decisionOver2++
|
|
}
|
|
|
|
sub plotq() {
|
|
; cx16.r14 = x, cx16.r15 = y, draw=draw
|
|
safe_plot(cx16.r14, cx16.r15, draw)
|
|
}
|
|
}
|
|
|
|
sub disc(uword @zp xcenter, uword @zp ycenter, ubyte @zp radius, bool draw) {
|
|
; Warning: NO BOUNDS CHECKS. Make sure circle fits in the screen.
|
|
; Midpoint algorithm, filled
|
|
if radius==0
|
|
return
|
|
ubyte @zp yy = 0
|
|
word @zp decisionOver2 = (1 as word)-radius
|
|
|
|
while radius>=yy {
|
|
horizontal_line(xcenter-radius, ycenter+yy, radius*$0002+1, draw)
|
|
horizontal_line(xcenter-radius, ycenter-yy, radius*$0002+1, draw)
|
|
horizontal_line(xcenter-yy, ycenter+radius, yy*$0002+1, draw)
|
|
horizontal_line(xcenter-yy, ycenter-radius, yy*$0002+1, draw)
|
|
yy++
|
|
if decisionOver2>=0 {
|
|
radius--
|
|
decisionOver2 -= radius*$0002
|
|
}
|
|
decisionOver2 += yy*$0002
|
|
decisionOver2++
|
|
}
|
|
}
|
|
|
|
sub safe_disc(uword @zp xcenter, uword @zp ycenter, ubyte @zp radius, bool draw) {
|
|
; Warning: NO BOUNDS CHECKS. Make sure circle fits in the screen.
|
|
; Midpoint algorithm, filled
|
|
if radius==0
|
|
return
|
|
ubyte @zp yy = 0
|
|
word @zp decisionOver2 = (1 as word)-radius
|
|
|
|
while radius>=yy {
|
|
safe_horizontal_line(xcenter-radius, ycenter+yy, radius*$0002+1, draw)
|
|
safe_horizontal_line(xcenter-radius, ycenter-yy, radius*$0002+1, draw)
|
|
safe_horizontal_line(xcenter-yy, ycenter+radius, yy*$0002+1, draw)
|
|
safe_horizontal_line(xcenter-yy, ycenter-radius, yy*$0002+1, draw)
|
|
yy++
|
|
if decisionOver2>=0 {
|
|
radius--
|
|
decisionOver2 -= radius*$0002
|
|
}
|
|
decisionOver2 += yy*$0002
|
|
decisionOver2++
|
|
}
|
|
}
|
|
|
|
sub plot(uword @zp xx, uword @zp yy, bool @zp draw) {
|
|
if draw {
|
|
if dont_stipple_flag
|
|
sys.gfx_plot(xx, yy, 255)
|
|
else {
|
|
if (xx ^ yy)&1
|
|
sys.gfx_plot(xx, yy, 255)
|
|
else
|
|
sys.gfx_plot(xx, yy, 0)
|
|
}
|
|
}
|
|
else
|
|
sys.gfx_plot(xx, yy, 0)
|
|
}
|
|
|
|
sub safe_plot(uword xx, uword yy, bool draw) {
|
|
; A plot that does bounds checks to see if the pixel is inside the screen.
|
|
if msb(xx)&$80!=0 or msb(yy)&$80!=0
|
|
return
|
|
if xx >= width or yy >= height
|
|
return
|
|
plot(xx, yy, draw)
|
|
}
|
|
|
|
sub pget(uword @zp xx, uword yy) -> ubyte {
|
|
return sys.gfx_getpixel(xx, yy)
|
|
}
|
|
|
|
sub fill(uword x, uword y, bool draw) {
|
|
; Non-recursive scanline flood fill.
|
|
; based loosely on code found here https://www.codeproject.com/Articles/6017/QuickFill-An-efficient-flood-fill-algorithm
|
|
; with the fixes applied to the seedfill_4 routine as mentioned in the comments.
|
|
const ubyte MAXDEPTH = 64
|
|
word @zp xx = x as word
|
|
word @zp yy = y as word
|
|
word[MAXDEPTH] @split @shared stack_xl
|
|
word[MAXDEPTH] @split @shared stack_xr
|
|
word[MAXDEPTH] @split @shared stack_y
|
|
byte[MAXDEPTH] @shared stack_dy
|
|
cx16.r12L = 0 ; stack pointer
|
|
word x1
|
|
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++
|
|
}
|
|
}
|
|
sub pop_stack() {
|
|
cx16.r12L--
|
|
x1 = stack_xl[cx16.r12L]
|
|
x2 = stack_xr[cx16.r12L]
|
|
yy = stack_y[cx16.r12L]
|
|
dy = stack_dy[cx16.r12L]
|
|
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 {
|
|
if pget(xx as uword, yy as uword) != cx16.r11L
|
|
break
|
|
xx--
|
|
}
|
|
if x1!=xx
|
|
horizontal_line(xx as uword+1, yy as uword, x1-xx as uword, cx16.r10L)
|
|
else
|
|
goto skip
|
|
|
|
left = xx + 1
|
|
if left < x1
|
|
push_stack(left, x1 - 1, yy, -dy)
|
|
xx = x1 + 1
|
|
|
|
do {
|
|
cx16.r9 = xx
|
|
while xx <= width-1 {
|
|
if pget(xx as uword, yy as uword) != cx16.r11L
|
|
break
|
|
xx++
|
|
}
|
|
if cx16.r9!=xx
|
|
horizontal_line(cx16.r9, yy as uword, (xx as uword)-cx16.r9, cx16.r10L)
|
|
|
|
push_stack(left, xx - 1, yy, dy)
|
|
if xx > x2 + 1
|
|
push_stack(x2 + 1, xx - 1, yy, -dy)
|
|
skip:
|
|
xx++
|
|
while xx <= x2 {
|
|
if pget(xx as uword, yy as uword) == cx16.r11L
|
|
break
|
|
xx++
|
|
}
|
|
left = xx
|
|
} until xx>x2
|
|
}
|
|
}
|
|
|
|
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.
|
|
; TODO vm bitmap charset
|
|
}
|
|
|
|
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.
|
|
; TODO vm bitmap charset
|
|
}
|
|
}
|