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// WebGLWorker client code
function assert(x) {
if (!x) throw 'failed assert';
}
function WebGLClient() {
var objects = {};
function fixArgs(command, args) {
switch (command) {
case 'getProgramParameter':
case 'getShaderParameter':
case 'uniform1i':
case 'uniform1f':
case 'uniform4fv':
case 'uniformMatrix4fv':
case 'getUniformLocation':
case 'useProgram':
case 'linkProgram':
case 'bindAttribLocation':
case 'compileShader':
case 'shaderSource': args[0] = objects[args[0]]; break;
case 'attachShader': args[0] = objects[args[0]]; args[1] = objects[args[1]]; break;
case 'bindTexture':
case 'bindBuffer': args[1] = args[1] ? objects[args[1]] : null; break;
}
return args;
}
function renderCommands(buffer) {
var ctx = Module.ctx;
var i = 0;
var len = buffer.length;
//dump('issuing commands, buffer len: ' + len + '\n');
while (i < len) {
var command = buffer[i++];
assert(typeof command === 'string')
var numArgs = buffer[i++];
assert(typeof numArgs === 'number', command);
//dump('issue ' + [command, numArgs, 'peek:' + buffer.slice(i, i+5)] + '\n');
if (numArgs === 0) {
//dump('issue: ' + command + '\n');
if (command === 'getError') {
assert(ctx.getError() === ctx.NO_ERROR, 'we cannot handle errors, we are async proxied WebGL');
} else {
ctx[command]();
}
} else if (numArgs > 0) {
var args = fixArgs(command, buffer.slice(i, i+numArgs));
i += numArgs;
//dump('issue+: ' + command + '(' + args + '), ' + numArgs + '\n');
if (command === 'getShaderParameter' || command === 'getProgramParameter') {
assert(ctx[command](args[0], args[1]), 'we cannot handle errors, we are async proxied WebGL');
} else {
ctx[command].apply(ctx, args);
}
} else {
// negative means a constructor, last argument is the id to save as
numArgs = -numArgs - 1;
var args = fixArgs(command, buffer.slice(i, i+numArgs));
i += numArgs;
var id = buffer[i++];
//dump('issue-: ' + command + '(' + args + '), ' + numArgs + '\n');
objects[id] = ctx[command].apply(ctx, args);
}
assert(i <= len);
}
}
var commandBuffers = [];
function renderAllCommands() {
// TODO: we can avoid running commands from buffers that are not the last, if they
// have no side effects, as each buffer is from a different frame
for (var i = 0; i < commandBuffers.length; i++) {
renderCommands(commandBuffers[i]);
}
commandBuffers.length = 0;
}
this.onmessage = function(msg) {
//dump('client GL got ' + JSON.stringify(msg) + '\n');
switch(msg.op) {
case 'render': {
if (commandBuffers.length === 0) {
// requestion a new frame, we will clear the buffers after rendering them
window.requestAnimationFrame(renderAllCommands);
}
commandBuffers.push(msg.commandBuffer);
break;
}
default: throw 'weird gl onmessage ' + JSON.stringify(msg);
}
};
}
WebGLClient.prefetch = function() {
var canvas = document.createElement('canvas');
var ctx = canvas.getContext('webgl-experimental') || canvas.getContext('webgl');
if (!ctx) return;
var parameters = {};
['MAX_VERTEX_ATTRIBS', 'MAX_TEXTURE_IMAGE_UNITS'].forEach(function(name) {
parameters[ctx[name]] = ctx.getParameter(ctx[name]);
});
worker.postMessage({ target: 'gl', op: 'setPrefetched', parameters: parameters, extensions: ctx.getSupportedExtensions() });
};
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