first working prototype of sprite drawing

src/ugui_sprite.c3

@@ -0,0 +1,130 @@
+module ugui;
+
+import std::collections::map;
+import std::io;
+import mqoi;
+
+const usz SRITES_PER_ATLAS = 64;
+
+struct Sprite {
+	Id id;
+	ushort u, v;
+	ushort w, h;
+}
+
+def SpriteMap = map::HashMap(<Id, Sprite>);
+
+struct SpriteAtlas {
+	Id id;
+	Atlas atlas;
+	SpriteMap sprites;
+	bool should_update;
+}
+
+
+// name: some examples are "icons" or "images"
+fn void! SpriteAtlas.init(&this, String name, AtlasType type, ushort width, ushort height)
+{
+	// FIXME: for now only RGBA32 format is supported
+	if (type != ATLAS_RGBA32) {
+		return UgAtlasError.INVALID_TYPE?;
+	}
+
+	this.id = name.hash();
+	this.atlas.new(this.id, AtlasType.ATLAS_RGBA32, width, height)!;
+	this.sprites.new_init(capacity: SRITES_PER_ATLAS);
+	this.should_update = false;
+}
+
+fn void! SpriteAtlas.free(&this)
+{
+	this.atlas.free();
+	this.sprites.free();
+}
+
+// FIXME: this should throw an error when a different pixel format than the atlas' is used
+fn Sprite*! SpriteAtlas.insert(&this, String name, char[] pixels, ushort w, ushort h, ushort stride)
+{
+	Sprite s;
+	s.id = name.hash();
+	Point uv = this.atlas.place(pixels, w, h, stride)!;
+	s.w = w;
+	s.h = h;
+	s.u = uv.x;
+	s.v = uv.y;
+	this.sprites.set(s.id, s);
+	this.should_update = true;
+	return this.sprites.get_ref(s.id);
+}
+
+fn Sprite*! SpriteAtlas.get(&this, String name)
+{
+	Id id = name.hash();
+	return this.sprites.get_ref(id);
+}
+
+fn Sprite*! SpriteAtlas.get_by_id(&this, Id id)
+{
+	return this.sprites.get_ref(id);
+}
+
+fn void! Ctx.sprite_atlas_create(&ctx, String name, AtlasType type, ushort w, ushort h)
+{
+	ctx.sprite_atlas.init(name, type, w, h)!;
+}
+
+fn Id Ctx.get_sprite_atlas_id(&ctx, String name)
+{
+	return name.hash();
+}
+
+fn void! Ctx.import_sprite_memory(&ctx, String name, char[] pixels, ushort w, ushort h, ushort stride)
+{
+	ctx.sprite_atlas.insert(name, pixels, w, h, stride)!;
+}
+
+fn void! Ctx.import_sprite_file_qoi(&ctx, String name, String path)
+{
+	mqoi::Desc image_desc;
+	uint w, h;
+
+	File file = file::open(path, "rb")!;
+	defer (void) file.close();
+
+	while (!mqoi::desc_done(&image_desc)) {
+		mqoi::desc_push(&image_desc, file.read_byte()!);
+	}
+	if (mqoi::desc_verify(&image_desc, &w, &h) != 0) {
+		return IoError.FILE_NOT_VALID?;
+	}
+
+	mqoi::Dec dec;
+	mqoi::Rgba* px;
+
+	usz idx;
+	char[] pixels = mem::new_array(char, (usz)w*h*4);
+	defer mem::free(pixels);
+
+	mqoi::dec_init(&dec, w*h);
+	while (!mqoi::dec_done(&dec)) {
+		mqoi::dec_push(&dec, file.read_byte()!);
+
+		while ((px = mqoi::dec_pop(&dec)) != null) {
+			pixels[idx..idx+3] = px.value;
+			idx += 4;
+		}
+	}
+
+	ctx.sprite_atlas.insert(name, pixels, (ushort)w, (ushort)h, (ushort)w)!;
+}
+
+// FIXME: test function, very different from every other function here
+fn void! Ctx.draw_sprite(&ctx, String name)
+{
+	Sprite* sprite = ctx.sprite_atlas.get(name)!;
+	Rect bounds = { 100, 100, sprite.w, sprite.h };
+	Rect uv = { sprite.u, sprite.v, sprite.w, sprite.h };
+	Id tex_id = ctx.sprite_atlas.id;
+
+	return ctx.push_sprite(bounds, uv, tex_id)!;
+}