We ball

client/renderer/core.ts

@@ -299,6 +299,35 @@ export function push_quad(
 	push_vertex(dx, y2, 0, u0, v1, r, g, b, a);
 }
 
+export function push_quad_vertices(
+	x0: number,
+	y0: number,
+	x1: number,
+	y1: number,
+	x2: number,
+	y2: number,
+	x3: number,
+	y3: number,
+	u0: number,
+	v0: number,
+	u1: number,
+	v1: number,
+	r = 1,
+	g = 1,
+	b = 1,
+	a = 1,
+) {
+	// triangle 1
+	push_vertex(x0, y0, 0, u0, v0, r, g, b, a);
+	push_vertex(x1, y1, 0, u1, v0, r, g, b, a);
+	push_vertex(x2, y2, 0, u1, v1, r, g, b, a);
+
+	// triangle 2
+	push_vertex(x0, y0, 0, u0, v0, r, g, b, a);
+	push_vertex(x2, y2, 0, u1, v1, r, g, b, a);
+	push_vertex(x3, y3, 0, u0, v1, r, g, b, a);
+}
+
 // internal
 
 function update_camera() {

client/renderer/textures.ts

@@ -1,4 +1,4 @@
-import { flush_batch, get_current_texture, gl, push_quad, set_current_texture } from "./core.ts";
+import { flush_batch, get_current_texture, gl, push_quad, push_quad_vertices, set_current_texture } from "./core.ts";
 import { Texture } from "./types.ts";
 
 export function load_texture(image: HTMLImageElement): Texture {
@@ -93,3 +93,64 @@ export function draw_texture_region(
 
 	push_quad(dx, dy, dw, dh, u0, v0, u1, v1, r, g, b, a);
 }
+
+export function draw_texture_region_skewed(
+	texture: Texture,
+	sx: number,
+	sy: number,
+	sw: number,
+	sh: number,
+	points: [
+		{ x: number; y: number }, // top-left
+		{ x: number; y: number }, // top-right
+		{ x: number; y: number }, // bottom-right
+		{ x: number; y: number }, // bottom-left
+	],
+	r = 1,
+	g = 1,
+	b = 1,
+	a = 1,
+	flip_x = false,
+	flip_y = false,
+) {
+	if (get_current_texture() !== texture.tex) {
+		flush_batch();
+		set_current_texture(texture.tex);
+	}
+
+	let u0 = sx / texture.width;
+	let v0 = sy / texture.height;
+	let u1 = (sx + sw) / texture.width;
+	let v1 = (sy + sh) / texture.height;
+
+	if (flip_x) {
+		[u0, u1] = [u1, u0];
+	}
+	if (flip_y) {
+		[v0, v1] = [v1, v0];
+	}
+
+	const p0 = points[0];
+	const p1 = points[1];
+	const p2 = points[2];
+	const p3 = points[3];
+
+	push_quad_vertices(
+		p0.x,
+		p0.y,
+		p1.x,
+		p1.y,
+		p2.x,
+		p2.y,
+		p3.x,
+		p3.y,
+		u0,
+		v0,
+		u1,
+		v1,
+		r,
+		g,
+		b,
+		a,
+	);
+}