diff options
| -rw-r--r-- | drawing.ha | 65 | ||||
| -rw-r--r-- | main.ha | 71 |
2 files changed, 84 insertions, 52 deletions
diff --git a/drawing.ha b/drawing.ha new file mode 100644 index 0000000..ff2aa71 --- /dev/null +++ b/drawing.ha @@ -0,0 +1,65 @@ +use sdl2; + + +// 2d position, x and y +type pos = (int, int); + +type drawing_state = struct { + // is the mouse button held down? + drawing: bool, + pos: pos, + picture: picture, +}; + +type picture = struct { + d: *[*]u32, + w: size, + h: size, +}; +// Returns array index of the pixel at position pos. +// Bounds check happens in here instead of using a slice type, so +// that it's easier to remove later. +fn pidx(pic: *picture, pos: pos) size = { + const (x,y) = pos; + const (xs,ys) = (x:size, y:size); + assert(0 <= x, "x position must not be less than 0"); + assert(0 <= y, "y position must not be less than 0"); + assert(xs < pic.w, "x position must be less than picture width"); + assert(ys < pic.h, "y position must be less than picture height"); + + return xs + pic.w*ys; +}; +fn pic_set(pic: *picture, pos: pos, val: u32) void = pic.d[pidx(pic,pos)] = val; +fn picture_from_surface(surf: *sdl2::SDL_Surface) picture = picture { + w = surf.w: size, + h = surf.h: size, + d = (surf.pixels as *opaque: *[*]u32), +}; + +fn min(a: int, b: int) int = if (a<b) a else b; +fn max(a: int, b: int) int = if (a<b) b else a; + +fn circle(dstate: *drawing_state, c: pos, r: int, color: u32) void = { + const (cx,cy) = c; + const ymin = max(0, cy-r); + const ymax = min(dstate.picture.h:int-1, cy+r); + const xmin = max(0, cx-r); + const xmax = min(dstate.picture.w:int-1, cx+r); + + const r2 = r*r + r; + + for (let y = ymin; y<=ymax; y+=1) { + const yd = y-cy; + for (let x = xmin; x<=xmax; x+=1) { + const xd = x-cx; + if (yd*yd + xd*xd <= r2) { + pic_set(&dstate.picture, (x,y), color); + }; + }; + }; + +}; + +fn do_drawing(dstate: *drawing_state) void = { + if (dstate.drawing) circle(dstate, dstate.pos, 20, 0xff0088); +}; @@ -5,6 +5,8 @@ export fn main() void = { sdl2::SDL_Init(sdl2::SDL_INIT_VIDEO)!; defer sdl2::SDL_Quit(); + fmt::println(size(i32), size(i64), size(int), size(size))!; + const win = sdl2::SDL_CreateWindow("hi", sdl2::SDL_WINDOWPOS_UNDEFINED, sdl2::SDL_WINDOWPOS_UNDEFINED, 640, 480, sdl2::SDL_WindowFlags::NONE)!; defer sdl2::SDL_DestroyWindow(win); @@ -21,14 +23,16 @@ export fn main() void = { fmt::println(wsurf.w * wsurf.h)!; fmt::println(sdl2::SDL_GetPixelFormatName(format.format))!; - const pic = picture_from_surface(wsurf); + let dstate = drawing_state { + drawing = false, + pos = (0,0), + picture = picture_from_surface(wsurf) + }; + let quit = false; let n = 0z; let lasttime = sdl2::SDL_GetTicks(); - let drawing = false; - let mousex = 0; - let mousey = 0; for (!quit) { let ev = sdl2::event { ... }; for (sdl2::SDL_PollEvent(&ev)! == 1) switch (ev.event_type) { @@ -38,20 +42,22 @@ export fn main() void = { if (keysym == sdl2::SDL_Keycode::ESCAPE) quit = true; case sdl2::SDL_EventType::MOUSEBUTTONDOWN, sdl2::SDL_EventType::MOUSEBUTTONUP => - const d = ev.button; - mousex = d.x; - mousey = d.y; - if (d.button == 1) - drawing = (d.state == 1); + const edata = ev.button; + dstate.pos = (edata.x, edata.y); + if (edata.button == 1) + dstate.drawing = (edata.state == 1); case sdl2::SDL_EventType::MOUSEMOTION => - const d = ev.motion; - mousex = d.x; - mousey = d.y; + const edata = ev.motion; + dstate.pos = (edata.x, edata.y); case => void; }; + do_drawing(&dstate); - if (drawing) circle(pic, mousex, mousey, 25, 0x00ffff); + + // if (drawing) { + // circle(pic, mousex, mousey, 5, 0x00ffff); + // }; // circle(pic, 100, 100, n:int, 0xff0000); @@ -70,43 +76,4 @@ export fn main() void = { }; }; -def WHITE = 0x556602; -def BLACK = 0x0; - -type picture = struct { - d: []u32, - w: size, - h: size, -}; -fn pidx(pic: picture, x: size, y: size) size = (pic.w*y)+x; -fn pic_set(pic: picture, x: size, y: size, val: u32) void = pic.d[pidx(pic,x,y)] = val; -fn picture_from_surface(surf: *sdl2::SDL_Surface) picture = picture { - w = surf.w: size, - h = surf.h: size, - d = (surf.pixels as *opaque: *[*]u32)[..surf.w*surf.h], -}; - -fn min(a: int, b: int) int = if (a<b) a else b; -fn max(a: int, b: int) int = if (a<b) b else a; - -fn circle(pic: picture, cx: int, cy: int, r: int, color: u32) void = { - const ymin = max(0, cy-r); - const ymax = min(pic.h:int-1, cy+r); - const xmin = max(0, cx-r); - const xmax = min(pic.w:int-1, cx+r); - - const r2 = r*r + r; - - for (let y = ymin; y<=ymax; y+=1) { - const yd = y-cy; - for (let x = xmin; x<=xmax; x+=1) { - const xd = x-cx; - if (yd*yd + xd*xd <= r2) { - // we already made sure x and y are both greater than 0 - pic_set(pic, x:size, y:size, color); - }; - }; - }; - -}; |