--- /dev/null
+
+let wasm_instance;
+let canvasElem;
+let canvasCtx;
+
+const MAGIC_CANVAS_NUMBER = 0x5052455A;
+
+let canvas_import_obj = {
+
+ init(canvas_name, length) {
+ const data = new Uint8Array(wasm_instance.exports.memory.buffer, canvas_name, length);
+ const str = new TextDecoder().decode(data);
+
+ canvasElem = document.getElementById(str);
+ if (canvasElem == null) return -1;
+
+ canvasElem.width = window.innerWidth;
+ canvasElem.height = window.innerHeight;
+
+ canvasCtx = canvasElem.getContext('2d');
+
+ return MAGIC_CANVAS_NUMBER;
+ },
+
+ clear(canvas, r, g, b, a) {
+ canvasCtx.fillStyle = `rgba(${r * 255}, ${g * 255}, ${b * 255}, ${a})`;
+ canvasCtx.fillRect(0, 0, canvasElem.width, canvasElem.height);
+ },
+
+ get_width(canvas) { return canvasElem.width; },
+ get_height(canvas) { return canvasElem.height; },
+
+ fillRect(canvas, x, y, w, h, r, g, b, a) {
+ canvasCtx.fillStyle = `rgba(${r * 255}, ${g * 255}, ${b * 255}, ${a})`;
+ canvasCtx.fillRect(x, y, w, h);
+ }
+}
+
+let import_obj = {
+ host: {
+ print_str(ptr, len) {
+ const data = new Uint8Array(wasm_instance.exports.memory.buffer, ptr, len);
+ const str = new TextDecoder().decode(data);
+ console.log(str);
+ },
+
+ exit(status) { console.warn("Attempted to call host.exit()."); }
+ },
+
+ canvas: canvas_import_obj
+}
+
+function main() {
+
+ fetch("prez.wasm")
+ .then(res => res.arrayBuffer())
+ .then(res => WebAssembly.instantiate(res, import_obj))
+ .then(({ instance }) => {
+ wasm_instance = instance;
+
+ instance.exports._start();
+ });
+
+}
+
+window.onload = main;
-
use package core
+Canvas :: struct {
+ Handle :: #type u32;
+
+ init :: (id: str) -> Handle #foreign "canvas" "init" ---
+ clear :: (handle: Handle, r: f32, g: f32, b: f32, a := 1.0f) -> Handle #foreign "canvas" "clear" ---
+ get_width :: (handle: Handle) -> u32 #foreign "canvas" "get_width" ---
+ get_height :: (handle: Handle) -> u32 #foreign "canvas" "get_height" ---
+ fill_rect :: (handle: Handle,
+ x: f32, y: f32, w: f32, h: f32,
+ r: f32, g: f32, b: f32, a := 1.0f) -> void #foreign "canvas" "fillRect" ---
+}
+
+setup_canvas :: () {
+ use Canvas;
+
+ canvas := init("prez_canvas");
+ if canvas == -1 {
+ println("Failed to set up canvas.");
+ return;
+ }
+
+ clear(canvas, 0.1, 0.1, 0.1);
+
+ width, height := cast(f32) get_width(canvas), cast(f32) get_height(canvas);
+ fill_rect(canvas, width / 2, height / 2, width / 2, height / 2, 1, 0, 0);
+}
+
main :: (args: [] cstr) {
- println("Got to main!");
+ setup_canvas();
}
projects / onyx-prez.git / commitdiff