Hilo/docs/api-zh/code/renderer/WebGLRenderer.js
2019-01-09 14:37:29 +08:00

572 lines
19 KiB
JavaScript

/**
* Hilo
* Copyright 2015 alibaba.com
* Licensed under the MIT License
*/
/**
* Heavily inspired by PIXI's SpriteRenderer:
* https://github.com/pixijs/pixi.js/blob/v3.0.9/src/core/sprites/webgl/SpriteRenderer.js
*/
var DEG2RAD = Math.PI / 180;
/**
* @class webgl画布渲染器。所有可视对象将渲染在canvas画布上。
* @augments Renderer
* @param {Object} properties 创建对象的属性参数。可包含此类所有可写属性。
* @module hilo/renderer/WebGLRenderer
* @requires hilo/core/Class
* @requires hilo/core/Hilo
* @requires hilo/renderer/Renderer
* @requires hilo/geom/Matrix
* @property {WebGLRenderingContext} gl webgl上下文。只读属性。
*/
var WebGLRenderer = Class.create(/** @lends WebGLRenderer.prototype */{
Extends: Renderer,
Statics:/** @lends WebGLRenderer */{
/**
* 最大批渲染数量。
* @type {Number}
*/
MAX_BATCH_NUM:2000,
/**
* 顶点属性数。只读属性。
* @type {Number}
*/
ATTRIBUTE_NUM:5,
/**
* 是否支持WebGL。只读属性。
* @type {Boolean}
*/
isSupport:function(){
if(this._isSupported == undefined){
var canvas = document.createElement('canvas');
if(canvas.getContext && (canvas.getContext('webgl')||canvas.getContext('experimental-webgl'))){
this._isSupported = true;
}
else{
this._isSupported = false;
}
}
return this._isSupported;
},
/**
* WebGL context Options
* @see https://developer.mozilla.org/en-US/docs/Web/API/WebGLRenderingContext/getContextAttributes
* @type {Object}
*/
contextOptions: null
},
renderType:'webgl',
gl:null,
_isContextLost:false,
_cacheTexture:{},
constructor: function(properties){
WebGLRenderer.superclass.constructor.call(this, properties);
var that = this;
var contextOptions = WebGLRenderer.contextOptions || {};
this.gl = this.canvas.getContext("webgl", contextOptions)||this.canvas.getContext('experimental-webgl', contextOptions);
this.maxBatchNum = WebGLRenderer.MAX_BATCH_NUM;
this.positionStride = WebGLRenderer.ATTRIBUTE_NUM * 4;
var vertexNum = this.maxBatchNum * WebGLRenderer.ATTRIBUTE_NUM * 4;
var indexNum = this.maxBatchNum * 6;
this.arrayBuffer = new ArrayBuffer(vertexNum * 4);
this.float32Array = new Float32Array(this.arrayBuffer);
this.uint32Array = new Uint32Array(this.arrayBuffer);
this.indexs = new Uint16Array(indexNum);
for (var i=0, j=0; i < indexNum; i += 6, j += 4)
{
this.indexs[i + 0] = j + 0;
this.indexs[i + 1] = j + 1;
this.indexs[i + 2] = j + 2;
this.indexs[i + 3] = j + 1;
this.indexs[i + 4] = j + 2;
this.indexs[i + 5] = j + 3;
}
this.batchIndex = 0;
this.sprites = [];
this.canvas.addEventListener('webglcontextlost', function(e){
that._isContextLost = true;
e.preventDefault();
}, false);
this.canvas.addEventListener('webglcontextrestored', function(e){
that._isContextLost = false;
that.setupWebGLStateAndResource();
}, false);
this.setupWebGLStateAndResource();
},
setupWebGLStateAndResource:function(){
var gl = this.gl;
gl.blendFunc(gl.ONE, gl.ONE_MINUS_SRC_ALPHA);
gl.clearColor(0, 0, 0, 0);
gl.disable(gl.DEPTH_TEST);
gl.disable(gl.CULL_FACE);
gl.enable(gl.BLEND);
this._cacheTexture = {};
this._initShaders();
this.defaultShader.active();
this.positionBuffer = gl.createBuffer();
this.indexBuffer = gl.createBuffer();
gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, this.indexBuffer);
gl.bufferData(gl.ELEMENT_ARRAY_BUFFER, this.indexs, gl.STATIC_DRAW);
gl.bindBuffer(gl.ARRAY_BUFFER, this.positionBuffer);
gl.bufferData(gl.ARRAY_BUFFER, this.arrayBuffer, gl.DYNAMIC_DRAW);
gl.vertexAttribPointer(this.a_position, 2, gl.FLOAT, false, this.positionStride, 0);//x, y
gl.vertexAttribPointer(this.a_TexCoord, 2, gl.FLOAT, false, this.positionStride, 2 * 4);//x, y
gl.vertexAttribPointer(this.a_tint, 4, gl.UNSIGNED_BYTE, true, this.positionStride, 4 * 4);//alpha
},
context: null,
/**
* @private
* @see Renderer#startDraw
*/
startDraw: function(target){
if(target.visible && target.alpha > 0){
if(target === this.stage){
this.clear();
}
return true;
}
return false;
},
/**
* @private
* @see Renderer#draw
*/
draw: function(target){
var w = target.width,
h = target.height;
//TODO:draw background
var bg = target.background; // jshint ignore:line
//draw image
var drawable = target.drawable, image = drawable && drawable.image;
if(image){
var rect = drawable.rect, sw = rect[2], sh = rect[3];
if(!w && !h){
//fix width/height TODO: how to get rid of this?
w = target.width = sw;
h = target.height = sh;
}
if(this.batchIndex >= this.maxBatchNum){
this._renderBatches();
}
var vertexs = this._createVertexs(image, rect[0], rect[1], sw, sh, 0, 0, w, h);
var index = this.batchIndex * this.positionStride;
var float32Array = this.float32Array;
var uint32Array = this.uint32Array;
var tint = (target.tint >> 16) + (target.tint & 0xff00) + ((target.tint & 0xff) << 16) + (target.__webglRenderAlpha * 255 << 24);
float32Array[index + 0] = vertexs[0];//x
float32Array[index + 1] = vertexs[1];//y
float32Array[index + 2] = vertexs[2];//uvx
float32Array[index + 3] = vertexs[3];//uvy
uint32Array[index + 4] = tint;//tint
float32Array[index + 5] = vertexs[4];
float32Array[index + 6] = vertexs[5];
float32Array[index + 7] = vertexs[6];
float32Array[index + 8] = vertexs[7];
uint32Array[index + 9] = tint;
float32Array[index + 10] = vertexs[8];
float32Array[index + 11] = vertexs[9];
float32Array[index + 12] = vertexs[10];
float32Array[index + 13] = vertexs[11];
uint32Array[index + 14] = tint;
float32Array[index + 15] = vertexs[12];
float32Array[index + 16] = vertexs[13];
float32Array[index + 17] = vertexs[14];
float32Array[index + 18] = vertexs[15];
uint32Array[index + 19] = tint;
var matrix = target.__webglWorldMatrix;
for(var i = 0;i < 4;i ++){
var x = float32Array[index + i*5];
var y = float32Array[index + i*5 + 1];
float32Array[index + i*5] = matrix.a*x + matrix.c*y + matrix.tx;
float32Array[index + i*5 + 1] = matrix.b*x + matrix.d*y + matrix.ty;
}
target.__textureImage = image;
this.sprites[this.batchIndex++] = target;
}
},
/**
* @private
* @see Renderer#endDraw
*/
endDraw: function(target){
if(target === this.stage){
this._renderBatches();
}
},
/**
* @private
* @see Renderer#transform
*/
transform: function(target){
var drawable = target.drawable;
if(drawable && drawable.domElement){
Hilo.setElementStyleByView(target);
return;
}
var scaleX = target.scaleX,
scaleY = target.scaleY;
if(target === this.stage){
var style = this.canvas.style,
oldScaleX = target._scaleX,
oldScaleY = target._scaleY,
isStyleChange = false;
if((!oldScaleX && scaleX != 1) || (oldScaleX && oldScaleX != scaleX)){
target._scaleX = scaleX;
style.width = scaleX * target.width + "px";
isStyleChange = true;
}
if((!oldScaleY && scaleY != 1) || (oldScaleY && oldScaleY != scaleY)){
target._scaleY = scaleY;
style.height = scaleY * target.height + "px";
isStyleChange = true;
}
if(isStyleChange){
target.updateViewport();
}
target.__webglWorldMatrix = target.__webglWorldMatrix||new Matrix(1, 0, 0, 1, 0, 0);
}
else if(target.parent){
target.__webglWorldMatrix = target.__webglWorldMatrix||new Matrix(1, 0, 0, 1, 0, 0);
this._setConcatenatedMatrix(target, target.parent);
}
if(target.alpha > 0) {
if(target.parent && target.parent.__webglRenderAlpha){
target.__webglRenderAlpha = target.alpha * target.parent.__webglRenderAlpha;
}
else{
target.__webglRenderAlpha = target.alpha;
}
}
},
/**
* @private
* @see Renderer#remove
*/
remove: function(target){
var drawable = target.drawable;
var elem = drawable && drawable.domElement;
if(elem){
var parentElem = elem.parentNode;
if(parentElem){
parentElem.removeChild(elem);
}
}
},
/**
* @private
* @see Renderer#clear
*/
clear: function(x, y, width, height){
this.gl.clear(this.gl.COLOR_BUFFER_BIT);
},
/**
* @private
* @see Renderer#resize
*/
resize: function(width, height){
if(this.width !== width || this.height !== height){
var canvas = this.canvas;
var stage = this.stage;
var style = canvas.style;
this.width = canvas.width = width;
this.height = canvas.height = height;
style.width = stage.width * stage.scaleX + 'px';
style.height = stage.height * stage.scaleY + 'px';
this.gl.viewport(0, 0, width, height);
this.canvasHalfWidth = width * .5;
this.canvasHalfHeight = height * .5;
this._uploadProjectionTransform(true);
}
},
_renderBatches:function(){
var gl = this.gl;
gl.bufferSubData(gl.ARRAY_BUFFER, 0, this.uint32Array.subarray(0, this.batchIndex * this.positionStride));
var startIndex = 0;
var batchNum = 0;
var preTextureImage = null;
for(var i = 0;i < this.batchIndex;i ++){
var sprite = this.sprites[i];
if(preTextureImage && preTextureImage !== sprite.__textureImage){
this._renderBatch(startIndex, i);
startIndex = i;
batchNum = 1;
}
preTextureImage = sprite.__textureImage;
}
this._renderBatch(startIndex, this.batchIndex);
this.batchIndex = 0;
},
_renderBatch:function(start, end){
var gl = this.gl;
var num = end - start;
if(num > 0){
gl.bindTexture(gl.TEXTURE_2D, this._getTexture(this.sprites[start]));
gl.drawElements(gl.TRIANGLES, num * 6, gl.UNSIGNED_SHORT, start * 6 * 2);
}
},
_uploadProjectionTransform:function(force){
if(!this._projectionTransformElements||force){
this._projectionTransformElements = new Float32Array([
1/this.canvasHalfWidth, 0, 0,
0, -1/this.canvasHalfHeight, 0,
-1, 1, 1,
]);
}
this.gl.uniformMatrix3fv(this.u_projectionTransform, false, this._projectionTransformElements);
},
_initShaders:function(){
var VSHADER_SOURCE ='\
attribute vec2 a_position;\n\
attribute vec2 a_TexCoord;\n\
attribute vec4 a_tint;\n\
uniform mat3 u_projectionTransform;\n\
varying vec2 v_TexCoord;\n\
varying vec4 v_tint;\n\
void main(){\n\
gl_Position = vec4((u_projectionTransform * vec3(a_position, 1.0)).xy, 1.0, 1.0);\n\
v_TexCoord = a_TexCoord;\n\
v_tint = vec4(a_tint.rgb * a_tint.a, a_tint.a);\n\
}\n\
';
var FSHADER_SOURCE = '\n\
precision mediump float;\n\
uniform sampler2D u_Sampler;\n\
varying vec2 v_TexCoord;\n\
varying vec4 v_tint;\n\
void main(){\n\
gl_FragColor = texture2D(u_Sampler, v_TexCoord) * v_tint;\n\
}\n\
';
this.defaultShader = new Shader(this, {
v:VSHADER_SOURCE,
f:FSHADER_SOURCE
},{
attributes:["a_position", "a_TexCoord", "a_tint"],
uniforms:["u_projectionTransform", "u_Sampler"]
});
},
_createVertexs:function(img, tx, ty, tw, th, x, y, w, h){
var tempVertexs = this.__tempVertexs||[];
var width = img.width;
var height = img.height;
tw = tw/width;
th = th/height;
tx = tx/width;
ty = ty/height;
w = w;
h = h;
x = x;
y = y;
if(tw + tx > 1){
tw = 1 - tx;
}
if(th + ty > 1){
th = 1 - ty;
}
var index = 0;
tempVertexs[index++] = x; tempVertexs[index++] = y; tempVertexs[index++] = tx; tempVertexs[index++] = ty;
tempVertexs[index++] = x+w;tempVertexs[index++] = y; tempVertexs[index++] = tx+tw; tempVertexs[index++] = ty;
tempVertexs[index++] = x; tempVertexs[index++] = y+h; tempVertexs[index++] = tx;tempVertexs[index++] = ty+th;
tempVertexs[index++] = x+w;tempVertexs[index++] = y+h;tempVertexs[index++] = tx+tw;tempVertexs[index++] = ty+th;
return tempVertexs;
},
_setConcatenatedMatrix:function(view, ancestor){
var mtx = view.__webglWorldMatrix;
var cos = 1, sin = 0,
rotation = view.rotation % 360,
pivotX = view.pivotX, pivotY = view.pivotY,
scaleX = view.scaleX, scaleY = view.scaleY,
transform = view.transform;
if (transform) {
mtx.copy(transform);
}
else {
if(rotation){
var r = rotation * DEG2RAD;
cos = Math.cos(r);
sin = Math.sin(r);
}
var pos = view.getAlignPosition();
mtx.a = cos*scaleX;
mtx.b = sin*scaleX;
mtx.c = -sin*scaleY;
mtx.d = cos*scaleY;
mtx.tx = pos.x - mtx.a * pivotX - mtx.c * pivotY;
mtx.ty = pos.y - mtx.b * pivotX - mtx.d * pivotY;
}
mtx.concat(ancestor.__webglWorldMatrix);
},
_getTexture:function(sprite){
var image = sprite.__textureImage;
var texture = this._cacheTexture[image.src];
if(!texture){
texture = this.activeShader.uploadTexture(image);
}
return texture;
}
});
/**
* shader
* @param {WebGLRenderer} renderer [description]
* @param {Object} source
* @param {String} source.v 顶点shader
* @param {String} source.f 片段shader
* @param {Object} attr
* @param {Array} attr.attributes attribute数组
* @param {Array} attr.uniforms uniform数组
*/
var Shader = function(renderer, source, attr){
this.renderer = renderer;
this.gl = renderer.gl;
this.program = this._createProgram(this.gl, source.v, source.f);
attr = attr||{};
this.attributes = attr.attributes||[];
this.uniforms = attr.uniforms||[];
};
Shader.prototype = {
active:function(){
var that = this;
var renderer = that.renderer;
var gl = that.gl;
var program = that.program;
if(program && gl){
renderer.activeShader = that;
gl.useProgram(program);
that.attributes.forEach(function(attribute){
renderer[attribute] = gl.getAttribLocation(program, attribute);
gl.enableVertexAttribArray(renderer[attribute]);
});
that.uniforms.forEach(function(uniform){
renderer[uniform] = gl.getUniformLocation(program, uniform);
});
if(that.width !== renderer.width || that.height !== renderer.height){
that.width = renderer.width;
that.height = renderer.height;
renderer._uploadProjectionTransform();
}
}
},
uploadTexture:function(image){
var gl = this.gl;
var renderer = this.renderer;
var texture = gl.createTexture();
var u_Sampler = renderer.u_Sampler;
gl.activeTexture(gl.TEXTURE0);
gl.bindTexture(gl.TEXTURE_2D, texture);
// gl.pixelStorei(gl.UNPACK_FLIP_Y_WEBGL, 1);
gl.pixelStorei(gl.UNPACK_PREMULTIPLY_ALPHA_WEBGL, 1);
gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, gl.RGBA, gl.UNSIGNED_BYTE, image);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE);
gl.uniform1i(u_Sampler, 0);
gl.bindTexture(gl.TEXTURE_2D, null);
this.renderer._cacheTexture[image.src] = texture;
return texture;
},
_createProgram:function(gl, vshader, fshader){
var vertexShader = this._createShader(gl, gl.VERTEX_SHADER, vshader);
var fragmentShader = this._createShader(gl, gl.FRAGMENT_SHADER, fshader);
if (!vertexShader || !fragmentShader) {
return null;
}
var program = gl.createProgram();
if (program) {
gl.attachShader(program, vertexShader);
gl.attachShader(program, fragmentShader);
gl.linkProgram(program);
gl.deleteShader(fragmentShader);
gl.deleteShader(vertexShader);
var linked = gl.getProgramParameter(program, gl.LINK_STATUS);
if (!linked) {
var error = gl.getProgramInfoLog(program);
console.log('Failed to link program: ' + error);
gl.deleteProgram(program);
return null;
}
}
return program;
},
_createShader:function(gl, type, source){
var shader = gl.createShader(type);
if(shader){
gl.shaderSource(shader, source);
gl.compileShader(shader);
var compiled = gl.getShaderParameter(shader, gl.COMPILE_STATUS);
if (!compiled) {
var error = gl.getShaderInfoLog(shader);
console.log('Failed to compile shader: ' + error);
gl.deleteShader(shader);
return null;
}
}
return shader;
}
};