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mirror of https://github.com/kkapsner/CanvasBlocker synced 2024-12-24 13:50:50 +01:00
CanvasBlocker/lib/webgl.js
2022-02-15 19:53:58 +01:00

261 lines
10 KiB
JavaScript

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
(function(){
"use strict";
const logging = require("./logging");
let scope;
if ((typeof exports) !== "undefined"){
scope = exports;
}
else {
scope = require.register("./webgl", {});
}
scope.copyCanvasToWebgl = function copyCanvasToWebgl(window, canvas, webGLVersion = "webgl"){
const webGlCanvas = canvas.cloneNode(true);
const context =
window.HTMLCanvasElement.prototype.getContext.call(webGlCanvas, webGLVersion) ||
window.HTMLCanvasElement.prototype.getContext.call(webGlCanvas, "experimental-" + webGLVersion);
if (!context){
// unable to get a context...
logging.warning("unable to create webgl context.");
return {canvas: false, context: false};
}
context.viewport(0, 0, webGlCanvas.width, webGlCanvas.height);
const program = context.createProgram();
const vertexShader = context.createShader(context.VERTEX_SHADER);
const vertex = "attribute vec4 a_position;\nattribute vec2 a_texCoord;\nvarying vec2 v_texCoord;\n" +
"void main(){\n\tgl_Position = a_position;\n\tv_texCoord = a_texCoord;\n}";
context.shaderSource(vertexShader, vertex);
context.compileShader(vertexShader);
if (!context.getShaderParameter(vertexShader, context.COMPILE_STATUS)){
context.deleteShader(vertexShader);
logging.warning("webgl: failed to compile vertex shader.");
return {canvas: false, context: false};
}
context.attachShader(program, vertexShader);
const fragmentShader = context.createShader(context.FRAGMENT_SHADER);
const fragmenter = "precision mediump float;\nuniform sampler2D u_image;\nvarying vec2 v_texCoord;\n" +
"void main(){\n\tgl_FragColor = texture2D(u_image, v_texCoord);\n}";
context.shaderSource(fragmentShader, fragmenter);
context.compileShader(fragmentShader);
if (!context.getShaderParameter(fragmentShader, context.COMPILE_STATUS)){
context.deleteShader(fragmentShader);
logging.warning("webgl: failed to compile fragmenter shader.");
return {canvas: false, context: false};
}
context.attachShader(program, fragmentShader);
context.linkProgram(program);
if (!context.getProgramParameter(program, context.LINK_STATUS)){
context.deleteProgram(program);
logging.warning("webgl: failed to link program.");
return {canvas: false, context: false};
}
context.useProgram(program);
const positionBuffer = context.createBuffer();
context.bindBuffer(context.ARRAY_BUFFER, positionBuffer);
context.bufferData(context.ARRAY_BUFFER, new Float32Array([
-1, -1,
-1, 1,
1, -1,
1, 1,
-1, 1,
1, -1
]), context.STATIC_DRAW);
const positionAttributeLocation = context.getAttribLocation(program, "a_position");
context.enableVertexAttribArray(positionAttributeLocation);
const size = 2; // 2 components per iteration
const type = context.FLOAT; // the data is 32bit floats
const normalize = false; // don't normalize the data
const stride = 0; // 0 = move forward size * sizeof(type) each iteration to get the next position
const offset = 0; // start at the beginning of the buffer
context.vertexAttribPointer(positionAttributeLocation, size, type, normalize, stride, offset);
const texCoordLocation = context.getAttribLocation(program, "a_texCoord");
// provide texture coordinates for the rectangle.
const texCoordBuffer = context.createBuffer();
context.bindBuffer(context.ARRAY_BUFFER, texCoordBuffer);
context.bufferData(context.ARRAY_BUFFER, new Float32Array([
0, 1,
0, 0,
1, 1,
1, 0,
0, 0,
1, 1
]), context.STATIC_DRAW);
context.enableVertexAttribArray(texCoordLocation);
context.vertexAttribPointer(texCoordLocation, 2, context.FLOAT, false, 0, 0);
context.bindTexture(context.TEXTURE_2D, context.createTexture());
context.texParameteri(context.TEXTURE_2D, context.TEXTURE_WRAP_S, context.CLAMP_TO_EDGE);
context.texParameteri(context.TEXTURE_2D, context.TEXTURE_WRAP_T, context.CLAMP_TO_EDGE);
context.texParameteri(context.TEXTURE_2D, context.TEXTURE_MIN_FILTER, context.NEAREST);
context.texParameteri(context.TEXTURE_2D, context.TEXTURE_MAG_FILTER, context.NEAREST);
context.texImage2D(context.TEXTURE_2D, 0, context.RGBA, context.RGBA, context.UNSIGNED_BYTE, canvas);
context.drawArrays(context.TRIANGLES /*primitiveType*/, 0 /*triangleOffset*/, 6 /*count*/);
return {webGlCanvas, context};
};
const webglRandom = require("./webglRandom");
let randomSupply = null;
scope.setRandomSupply = function(supply){
randomSupply = supply;
webglRandom.setRandomSupply(supply);
};
function getNumber({originalValue, max, index, window}){
const bitLength = Math.floor(Math.log2(max) + 1);
const rng = randomSupply.getBitRng(bitLength, window);
let value = 0;
for (let i = 0; i < bitLength; i += 1){
value <<= 1;
value ^= rng(originalValue, index + i);
}
return value;
}
const parameterFakeTypes = {
preference: function(originalValue, definition, window, prefs){
const settingValue = prefs(definition.preferenceName) || originalValue;
switch (settingValue){
case "{undefined}":
return undefined;
case "{false}":
return false;
case "{empty}":
return "";
case "{disabled}":
return null;
case "{random vendor}":
return webglRandom.getRandomVendor(window);
case "{random renderer}":
return webglRandom.getRandomRenderer(window);
}
if (settingValue.startsWith("<") && settingValue.endsWith(">")){
return webglRandom.pickOneFromTree(settingValue, window);
}
return settingValue;
},
decimal: function(originalValue, definition, window){
const int = Math.floor(originalValue);
if (int !== originalValue){
const decimal = originalValue - int;
const rng = randomSupply.getRng(1, window);
const newDecimal = decimal * (rng(definition.pname) / 0xFFFFFFFF);
return int + newDecimal;
}
else {
return originalValue;
}
},
shift: function(originalValue, definition, window){
const value = getNumber({originalValue, max: definition.max, index: definition.pname, window});
return originalValue >>> value;
},
"-": function(originalValue, definition, window){
const value = getNumber({originalValue, max: definition.max, index: definition.pname, window}) *
(definition.factor || 1);
if (value > originalValue){
return 0;
}
return originalValue - value;
}
};
const parameterChangeDefinition = {
2928: {name: "DEPTH_RANGE", type: "decimal", isArray: true},
3379: {name: "MAX_TEXTURE_SIZE", type: "shift", max: 1},
3386: {name: "MAX_VIEWPORT_DIMS", type: "shift", max: 1, isArray: true},
32883: {name: "MAX_3D_TEXTURE_SIZE", type: "shift", max: 1},
33000: {name: "MAX_ELEMENTS_VERTICES", type: "-", max: 3, factor: 50},
33001: {name: "MAX_ELEMENTS_INDICES", type: "-", max: 3, factor: 50},
33901: {name: "ALIASED_POINT_SIZE_RANGE", type: "decimal", isArray: true},
33902: {name: "ALIASED_LINE_WIDTH_RANGE", type: "decimal", isArray: true},
34024: {name: "MAX_RENDERBUFFER_SIZE", type: "shift", max: 1},
34045: {name: "MAX_TEXTURE_LOD_BIAS", type: "-", max: 1, factor: 1},
34076: {name: "MAX_CUBE_MAP_TEXTURE_SIZE", type: "shift", max: 1},
34921: {name: "MAX_VERTEX_ATTRIBS", type: "shift", max: 1},
34930: {name: "MAX_TEXTURE_IMAGE_UNITS", type: "shift", max: 1},
35071: {name: "MAX_ARRAY_TEXTURE_LAYERS", type: "shift", max: 1},
35371: {name: "MAX_VERTEX_UNIFORM_BLOCKS", type: "-", max: 1, factor: 1},
35373: {name: "MAX_FRAGMENT_UNIFORM_BLOCKS", type: "-", max: 1, factor: 1},
35374: {name: "MAX_COMBINED_UNIFORM_BLOCKS", type: "-", max: 3, factor: 1},
35375: {name: "MAX_UNIFORM_BUFFER_BINDINGS", type: "-", max: 3, factor: 1},
35376: {name: "MAX_UNIFORM_BLOCK_SIZE", type: "shift", max: 1},
35377: {name: "MAX_COMBINED_VERTEX_UNIFORM_COMPONENTS", type: "-", max: 7, factor: 10},
35379: {name: "MAX_COMBINED_FRAGMENT_UNIFORM_COMPONENTS", type: "-", max: 7, factor: 10},
35657: {name: "MAX_FRAGMENT_UNIFORM_COMPONENTS", type: "shift", max: 1},
35658: {name: "MAX_VERTEX_UNIFORM_COMPONENTS", type: "shift", max: 1},
35659: {name: "MAX_VARYING_COMPONENTS", type: "shift", max: 1},
35660: {name: "MAX_VERTEX_TEXTURE_IMAGE_UNITS", type: "shift", max: 1},
35661: {name: "MAX_COMBINED_TEXTURE_IMAGE_UNITS", type: "-", max: 1, factor: 2},
35968: {name: "MAX_TRANSFORM_FEEDBACK_SEPARATE_COMPONENTS", type: "shift", max: 1},
35978: {name: "MAX_TRANSFORM_FEEDBACK_INTERLEAVED_COMPONENTS", type: "shift", max: 1},
36203: {name: "MAX_ELEMENT_INDEX", type: "-", max: 15, factor: 1},
36347: {name: "MAX_VERTEX_UNIFORM_VECTORS", type: "shift", max: 1},
36348: {name: "MAX_VARYING_VECTORS", type: "shift", max: 1},
36349: {name: "MAX_FRAGMENT_UNIFORM_VECTORS", type: "shift", max: 1},
37154: {name: "MAX_VERTEX_OUTPUT_COMPONENTS", type: "shift", max: 1},
37157: {name: "MAX_FRAGMENT_INPUT_COMPONENTS", type: "shift", max: 1},
7936: {name: "VENDOR", type: "preference", preferenceName: "webGLVendor"},
7937: {name: "RENDERER", type: "preference", preferenceName: "webGLRenderer"},
37445: {name: "UNMASKED_VENDOR_WEBGL", type: "preference", preferenceName: "webGLUnmaskedVendor"},
37446: {name: "UNMASKED_RENDERER_WEBGL", type: "preference", preferenceName: "webGLUnmaskedRenderer"}
};
scope.initializeParameterDefinitions = function(){
function singleFake(originalValue, window, prefs){
const value = parameterFakeTypes[this.type](originalValue, this, window, prefs);
const faked = value !== originalValue;
this.fake = function(){
return {value, faked};
};
return {value, faked};
}
function arrayFake(originalValue, window, prefs){
let faked = false;
let fakedValue = [];
for (let i = 0; i < originalValue.length; i += 1){
fakedValue[i] = parameterFakeTypes[this.type](originalValue[i], this, window, prefs);
faked = faked || originalValue[i] !== fakedValue[i];
originalValue[i] = fakedValue[i];
}
this.fake = function(originalValue){
if (faked){
for (let i = 0; i < originalValue.length; i += 1){
originalValue[i] = fakedValue[i];
}
}
return {
value: originalValue,
faked
};
};
return {
value: originalValue,
faked
};
}
Object.keys(parameterChangeDefinition).forEach(function(parameterName){
const definition = parameterChangeDefinition[parameterName];
definition.pname = parameterName;
if (!definition.fake){
definition.fake = definition.isArray? arrayFake: singleFake;
}
});
};
scope.parameterChangeDefinition = parameterChangeDefinition;
}());