-const memory = new WebAssembly.Memory( { initial: 2, maximum: 8 })
+const canvas = document.querySelector('canvas')
+
+// hidpi
+const width = canvas.width, height = canvas.height
+canvas.style.width = width + 'px'
+canvas.style.height = height + 'px'
+canvas.width = width * window.devicePixelRatio
+canvas.height = height * window.devicePixelRatio
+
+const gl = canvas.getContext('webgl')
+
+const shaderMap = new Map()
+var currentShaderId = 0
+function createShaderId() {
+ const id = currentShaderId
+ currentShaderId += 1
+ return id
+}
+
+var memory
+var decoder = new TextDecoder('utf-8')
+
+function readUint32(buffer, addr) {
+ const view = new DataView(buffer)
+ return view.getUint32(addr, true)
+}
+
const imports = {
env: {
- __syscall1: (n, a) => console.log(n),
- __syscall3: (n, a, b, c) => console.log(n),
- __syscall5: (n, a, b, c, d, e) => console.log(n)
+ glCreateShader: shaderType => {
+ const id = createShaderId()
+ const shader = gl.createShader(shaderType)
+ shaderMap.set(id, shader)
+ return id
+ },
+ glShaderSource: (id, numSrcs, srcs, lens) => {
+ const shader = shaderMap.get(id)
+ var totalSource = ''
+ for (let i = 0; i < numSrcs; i++) {
+ const addr = srcs + i * 4
+ const src = readUint32(memory.buffer, addr)
+ const len = readUint32(memory.buffer, lens + i * 4)
+ totalSource += decoder.decode(memory.buffer.slice(src, src + len))
+ }
+ gl.shaderSource(shader, totalSource)
+ },
+ glCompileShader: a => gl.compileShader(shaderMap.get(a))
}
}
function instantiate(bytes) {
return WebAssembly.compile(bytes).
- then(m => new WebAssembly.Instance(m, imports));
+ then(m => {
+ const inst = new WebAssembly.Instance(m, imports)
+ memory = inst.exports.memory
+ return inst
+ });
}
fetch('test.wasm')