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// paintui handles turning sdl input things
// into drawing instructions
// it might have some kind of state machine
// for doing smooth lines between discrete mouse positions
// all mouse pos stuff in this module is in world coordinates
// someone else is responsible for doing the transform from
// screen to world coords.
use drawing;
use drawing::{pos};
export const sizes: [_]u8 = [
1, 2, 4, 8, 16, 32, 48, 64, 80, 96, 112, 128
];
const colors: [_]u32 = [
0xffffff, // white
0xff4040, // red
0xff8000, // orange
0xc0c040, // yellow
0x00c000, // green
0x00c0c0, // teal
0x4040ff, // blue
0xc000c0, // purple
0x808080, // grey
0x000000, // black
];
export type state = struct {
// last known mouse position, in world coordinates
last_mouse_pos: pos,
// last known mouse pressed-ness
last_mouse_pressed: bool,
size_idx: size,
color: u32
};
fn abs(x: i32) i32 = if(x < 0) -x else x;
export fn tick(
pstate: *state,
mouse_pos: pos, mouse_pressed: bool
) (void | drawing::op) = {
// always update last_mouse_pos and last_mouse_pressed
defer {
pstate.last_mouse_pos = mouse_pos;
pstate.last_mouse_pressed = mouse_pressed;
};
const radius = sizes[pstate.size_idx];
const newly_pressed = mouse_pressed && !pstate.last_mouse_pressed;
const position_moved = (mouse_pos.0 != pstate.last_mouse_pos.0
|| mouse_pos.1 != pstate.last_mouse_pos.1);
if (!mouse_pressed) return void;
return if (newly_pressed) drawing::op_circle {
pos = mouse_pos,
radius = radius,
color = pstate.color,
} else if (position_moved) drawing::op_stroke {
pos0 = pstate.last_mouse_pos,
pos1 = mouse_pos,
radius = radius,
color = pstate.color,
} else void;
};
export fn mousewheel(pstate: *state, amt: i32) void = {
if (amt < 0 && pstate.size_idx > 0)
pstate.size_idx -= 1
else if (amt > 0 && pstate.size_idx < len(sizes) - 1)
pstate.size_idx += 1;
};
export fn key(pstate: *state, key: uint) void = {
assert(key <= 9, "what what what what what");
pstate.color = colors[key];
};
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