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sangdrea/canvas-renderer.js

Last active November 17, 2016 02:47
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canvas-renderer.js
/**
* @author mrdoob / http://mrdoob.com/
*/
THREE.SpriteCanvasMaterial = function ( parameters ) {
THREE.Material.call( this );
this.type = 'SpriteCanvasMaterial';
this.color = new THREE.Color( 0xffffff );
this.program = function ( context, color ) {};
this.setValues( parameters );
};
THREE.SpriteCanvasMaterial.prototype = Object.create( THREE.Material.prototype );
THREE.SpriteCanvasMaterial.prototype.constructor = THREE.SpriteCanvasMaterial;
THREE.SpriteCanvasMaterial.prototype.clone = function () {
var material = new THREE.SpriteCanvasMaterial();
THREE.Material.prototype.clone.call( this, material );
material.color.copy( this.color );
material.program = this.program;
return material;
};
//
THREE.CanvasRenderer = function ( parameters ) {
console.log( 'THREE.CanvasRenderer', THREE.REVISION );
var smoothstep = THREE.Math.smoothstep;
parameters = parameters || {};
var _this = this,
_renderData, _elements, _lights,
_projector = new THREE.Projector(),
_canvas = parameters.canvas !== undefined
? parameters.canvas
: document.createElement( 'canvas' ),
_canvasWidth = _canvas.width,
_canvasHeight = _canvas.height,
_canvasWidthHalf = Math.floor( _canvasWidth / 2 ),
_canvasHeightHalf = Math.floor( _canvasHeight / 2 ),
_viewportX = 0,
_viewportY = 0,
_viewportWidth = _canvasWidth,
_viewportHeight = _canvasHeight,
pixelRatio = 1,
_context = _canvas.getContext( '2d', {
alpha: parameters.alpha === true
} ),
_clearColor = new THREE.Color( 0x000000 ),
_clearAlpha = parameters.alpha === true ? 0 : 1,
_contextGlobalAlpha = 1,
_contextGlobalCompositeOperation = 0,
_contextStrokeStyle = null,
_contextFillStyle = null,
_contextLineWidth = null,
_contextLineCap = null,
_contextLineJoin = null,
_contextLineDash = [],
_camera,
_v1, _v2, _v3, _v4,
_v5 = new THREE.RenderableVertex(),
_v6 = new THREE.RenderableVertex(),
_v1x, _v1y, _v2x, _v2y, _v3x, _v3y,
_v4x, _v4y, _v5x, _v5y, _v6x, _v6y,
_color = new THREE.Color(),
_color1 = new THREE.Color(),
_color2 = new THREE.Color(),
_color3 = new THREE.Color(),
_color4 = new THREE.Color(),
_diffuseColor = new THREE.Color(),
_emissiveColor = new THREE.Color(),
_lightColor = new THREE.Color(),
_patterns = {},
_image, _uvs,
_uv1x, _uv1y, _uv2x, _uv2y, _uv3x, _uv3y,
_clipBox = new THREE.Box2(),
_clearBox = new THREE.Box2(),
_elemBox = new THREE.Box2(),
_ambientLight = new THREE.Color(),
_directionalLights = new THREE.Color(),
_pointLights = new THREE.Color(),
_vector3 = new THREE.Vector3(), // Needed for PointLight
_centroid = new THREE.Vector3(),
_normal = new THREE.Vector3(),
_normalViewMatrix = new THREE.Matrix3();
// dash+gap fallbacks for Firefox and everything else
if ( _context.setLineDash === undefined ) {
_context.setLineDash = function () {}
}
this.domElement = _canvas;
this.autoClear = true;
this.sortObjects = true;
this.sortElements = true;
this.info = {
render: {
vertices: 0,
faces: 0
}
}
// WebGLRenderer compatibility
this.supportsVertexTextures = function () {};
this.setFaceCulling = function () {};
//
this.getPixelRatio = function () {
return pixelRatio;
};
this.setPixelRatio = function ( value ) {
pixelRatio = value;
};
this.setSize = function ( width, height, updateStyle ) {
_canvasWidth = width * pixelRatio;
_canvasHeight = height * pixelRatio;
_canvas.width = _canvasWidth;
_canvas.height = _canvasHeight;
_canvasWidthHalf = Math.floor( _canvasWidth / 2 );
_canvasHeightHalf = Math.floor( _canvasHeight / 2 );
if ( updateStyle !== false ) {
_canvas.style.width = width + 'px';
_canvas.style.height = height + 'px';
}
_clipBox.min.set( -_canvasWidthHalf, -_canvasHeightHalf ),
_clipBox.max.set( _canvasWidthHalf, _canvasHeightHalf );
_clearBox.min.set( - _canvasWidthHalf, - _canvasHeightHalf );
_clearBox.max.set( _canvasWidthHalf, _canvasHeightHalf );
_contextGlobalAlpha = 1;
_contextGlobalCompositeOperation = 0;
_contextStrokeStyle = null;
_contextFillStyle = null;
_contextLineWidth = null;
_contextLineCap = null;
_contextLineJoin = null;
this.setViewport( 0, 0, width, height );
};
this.setViewport = function ( x, y, width, height ) {
_viewportX = x * pixelRatio;
_viewportY = y * pixelRatio;
_viewportWidth = width * pixelRatio;
_viewportHeight = height * pixelRatio;
};
this.setScissor = function () {};
this.enableScissorTest = function () {};
this.setClearColor = function ( color, alpha ) {
_clearColor.set( color );
_clearAlpha = alpha !== undefined ? alpha : 1;
_clearBox.min.set( - _canvasWidthHalf, - _canvasHeightHalf );
_clearBox.max.set( _canvasWidthHalf, _canvasHeightHalf );
};
this.setClearColorHex = function ( hex, alpha ) {
console.warn( 'THREE.CanvasRenderer: .setClearColorHex() is being removed. Use .setClearColor() instead.' );
this.setClearColor( hex, alpha );
};
this.getClearColor = function () {
return _clearColor;
};
this.getClearAlpha = function () {
return _clearAlpha;
};
this.getMaxAnisotropy = function () {
return 0;
};
this.clear = function () {
if ( _clearBox.empty() === false ) {
_clearBox.intersect( _clipBox );
_clearBox.expandByScalar( 2 );
_clearBox.min.x = _clearBox.min.x + _canvasWidthHalf;
_clearBox.min.y = - _clearBox.min.y + _canvasHeightHalf; // higher y value !
_clearBox.max.x = _clearBox.max.x + _canvasWidthHalf;
_clearBox.max.y = - _clearBox.max.y + _canvasHeightHalf; // lower y value !
if ( _clearAlpha < 1 ) {
_context.clearRect(
_clearBox.min.x | 0,
_clearBox.max.y | 0,
( _clearBox.max.x - _clearBox.min.x ) | 0,
( _clearBox.min.y - _clearBox.max.y ) | 0
);
}
if ( _clearAlpha > 0 ) {
setBlending( THREE.NormalBlending );
setOpacity( 1 );
setFillStyle( 'rgba(' + Math.floor( _clearColor.r * 255 ) + ',' + Math.floor( _clearColor.g * 255 ) + ',' + Math.floor( _clearColor.b * 255 ) + ',' + _clearAlpha + ')' );
_context.fillRect(
_clearBox.min.x | 0,
_clearBox.max.y | 0,
( _clearBox.max.x - _clearBox.min.x ) | 0,
( _clearBox.min.y - _clearBox.max.y ) | 0
);
}
_clearBox.makeEmpty();
}
};
// compatibility
this.clearColor = function () {};
this.clearDepth = function () {};
this.clearStencil = function () {};
this.render = function ( scene, camera ) {
if ( camera instanceof THREE.Camera === false ) {
console.error( 'THREE.CanvasRenderer.render: camera is not an instance of THREE.Camera.' );
return;
}
if ( this.autoClear === true ) this.clear();
_this.info.render.vertices = 0;
_this.info.render.faces = 0;
_context.setTransform( _viewportWidth / _canvasWidth, 0, 0, - _viewportHeight / _canvasHeight, _viewportX, _canvasHeight - _viewportY );
_context.translate( _canvasWidthHalf, _canvasHeightHalf );
_renderData = _projector.projectScene( scene, camera, this.sortObjects, this.sortElements );
_elements = _renderData.elements;
_lights = _renderData.lights;
_camera = camera;
_normalViewMatrix.getNormalMatrix( camera.matrixWorldInverse );
/* DEBUG
setFillStyle( 'rgba( 0, 255, 255, 0.5 )' );
_context.fillRect( _clipBox.min.x, _clipBox.min.y, _clipBox.max.x - _clipBox.min.x, _clipBox.max.y - _clipBox.min.y );
*/
calculateLights();
for ( var e = 0, el = _elements.length; e < el; e ++ ) {
var element = _elements[ e ];
var material = element.material;
if ( material === undefined || material.opacity === 0 ) continue;
_elemBox.makeEmpty();
if ( element instanceof THREE.RenderableSprite ) {
_v1 = element;
_v1.x *= _canvasWidthHalf; _v1.y *= _canvasHeightHalf;
renderSprite( _v1, element, material );
} else if ( element instanceof THREE.RenderableLine ) {
_v1 = element.v1; _v2 = element.v2;
_v1.positionScreen.x *= _canvasWidthHalf; _v1.positionScreen.y *= _canvasHeightHalf;
_v2.positionScreen.x *= _canvasWidthHalf; _v2.positionScreen.y *= _canvasHeightHalf;
_elemBox.setFromPoints( [
_v1.positionScreen,
_v2.positionScreen
] );
if ( _clipBox.isIntersectionBox( _elemBox ) === true ) {
renderLine( _v1, _v2, element, material );
}
} else if ( element instanceof THREE.RenderableFace ) {
_v1 = element.v1; _v2 = element.v2; _v3 = element.v3;
if ( _v1.positionScreen.z < - 1 || _v1.positionScreen.z > 1 ) continue;
if ( _v2.positionScreen.z < - 1 || _v2.positionScreen.z > 1 ) continue;
if ( _v3.positionScreen.z < - 1 || _v3.positionScreen.z > 1 ) continue;
_v1.positionScreen.x *= _canvasWidthHalf; _v1.positionScreen.y *= _canvasHeightHalf;
_v2.positionScreen.x *= _canvasWidthHalf; _v2.positionScreen.y *= _canvasHeightHalf;
_v3.positionScreen.x *= _canvasWidthHalf; _v3.positionScreen.y *= _canvasHeightHalf;
if ( material.overdraw > 0 ) {
expand( _v1.positionScreen, _v2.positionScreen, material.overdraw );
expand( _v2.positionScreen, _v3.positionScreen, material.overdraw );
expand( _v3.positionScreen, _v1.positionScreen, material.overdraw );
}
_elemBox.setFromPoints( [
_v1.positionScreen,
_v2.positionScreen,
_v3.positionScreen
] );
if ( _clipBox.isIntersectionBox( _elemBox ) === true ) {
renderFace3( _v1, _v2, _v3, 0, 1, 2, element, material );
}
}
/* DEBUG
setLineWidth( 1 );
setStrokeStyle( 'rgba( 0, 255, 0, 0.5 )' );
_context.strokeRect( _elemBox.min.x, _elemBox.min.y, _elemBox.max.x - _elemBox.min.x, _elemBox.max.y - _elemBox.min.y );
*/
_clearBox.union( _elemBox );
}
/* DEBUG
setLineWidth( 1 );
setStrokeStyle( 'rgba( 255, 0, 0, 0.5 )' );
_context.strokeRect( _clearBox.min.x, _clearBox.min.y, _clearBox.max.x - _clearBox.min.x, _clearBox.max.y - _clearBox.min.y );
*/
_context.setTransform( 1, 0, 0, 1, 0, 0 );
};
//
function calculateLights() {
_ambientLight.setRGB( 0, 0, 0 );
_directionalLights.setRGB( 0, 0, 0 );
_pointLights.setRGB( 0, 0, 0 );
for ( var l = 0, ll = _lights.length; l < ll; l ++ ) {
var light = _lights[ l ];
var lightColor = light.color;
if ( light instanceof THREE.AmbientLight ) {
_ambientLight.add( lightColor );
} else if ( light instanceof THREE.DirectionalLight ) {
// for sprites
_directionalLights.add( lightColor );
} else if ( light instanceof THREE.PointLight ) {
// for sprites
_pointLights.add( lightColor );
}
}
}
function calculateLight( position, normal, color ) {
for ( var l = 0, ll = _lights.length; l < ll; l ++ ) {
var light = _lights[ l ];
_lightColor.copy( light.color );
if ( light instanceof THREE.DirectionalLight ) {
var lightPosition = _vector3.setFromMatrixPosition( light.matrixWorld ).normalize();
var amount = normal.dot( lightPosition );
if ( amount <= 0 ) continue;
amount *= light.intensity;
color.add( _lightColor.multiplyScalar( amount ) );
} else if ( light instanceof THREE.PointLight ) {
var lightPosition = _vector3.setFromMatrixPosition( light.matrixWorld );
var amount = normal.dot( _vector3.subVectors( lightPosition, position ).normalize() );
if ( amount <= 0 ) continue;
amount *= light.distance == 0 ? 1 : 1 - Math.min( position.distanceTo( lightPosition ) / light.distance, 1 );
if ( amount == 0 ) continue;
amount *= light.intensity;
color.add( _lightColor.multiplyScalar( amount ) );
}
}
}
function renderSprite( v1, element, material ) {
setOpacity( material.opacity );
setBlending( material.blending );
var scaleX = element.scale.x * _canvasWidthHalf;
var scaleY = element.scale.y * _canvasHeightHalf;
var dist = 0.5 * Math.sqrt( scaleX * scaleX + scaleY * scaleY ); // allow for rotated sprite
_elemBox.min.set( v1.x - dist, v1.y - dist );
_elemBox.max.set( v1.x + dist, v1.y + dist );
if ( material instanceof THREE.SpriteMaterial ) {
var texture = material.map;
if ( texture !== null && texture.image !== undefined ) {
if ( texture.hasEventListener( 'update', onTextureUpdate ) === false ) {
if ( texture.image.width > 0 ) {
textureToPattern( texture );
}
texture.addEventListener( 'update', onTextureUpdate );
}
var pattern = _patterns[ texture.id ];
if ( pattern !== undefined ) {
setFillStyle( pattern );
} else {
setFillStyle( 'rgba( 0, 0, 0, 1 )' );
}
//
var bitmap = texture.image;
var ox = bitmap.width * texture.offset.x;
var oy = bitmap.height * texture.offset.y;
var sx = bitmap.width * texture.repeat.x;
var sy = bitmap.height * texture.repeat.y;
var cx = scaleX / sx;
var cy = scaleY / sy;
_context.save();
_context.translate( v1.x, v1.y );
if ( material.rotation !== 0 ) _context.rotate( material.rotation );
_context.translate( - scaleX / 2, - scaleY / 2 );
_context.scale( cx, cy );
_context.translate( - ox, - oy );
_context.fillRect( ox, oy, sx, sy );
_context.restore();
} else {
// no texture
setFillStyle( material.color.getStyle() );
_context.save();
_context.translate( v1.x, v1.y );
if ( material.rotation !== 0 ) _context.rotate( material.rotation );
_context.scale( scaleX, - scaleY );
_context.fillRect( - 0.5, - 0.5, 1, 1 );
_context.restore();
}
} else if ( material instanceof THREE.SpriteCanvasMaterial ) {
setStrokeStyle( material.color.getStyle() );
setFillStyle( material.color.getStyle() );
_context.save();
_context.translate( v1.x, v1.y );
if ( material.rotation !== 0 ) _context.rotate( material.rotation );
_context.scale( scaleX, scaleY );
material.program( _context );
_context.restore();
}
/* DEBUG
setStrokeStyle( 'rgb(255,255,0)' );
_context.beginPath();
_context.moveTo( v1.x - 10, v1.y );
_context.lineTo( v1.x + 10, v1.y );
_context.moveTo( v1.x, v1.y - 10 );
_context.lineTo( v1.x, v1.y + 10 );
_context.stroke();
*/
}
function renderLine( v1, v2, element, material ) {
setOpacity( material.opacity );
setBlending( material.blending );
_context.beginPath();
_context.moveTo( v1.positionScreen.x, v1.positionScreen.y );
_context.lineTo( v2.positionScreen.x, v2.positionScreen.y );
if ( material instanceof THREE.LineBasicMaterial ) {
setLineWidth( material.linewidth );
setLineCap( material.linecap );
setLineJoin( material.linejoin );
if ( material.vertexColors !== THREE.VertexColors ) {
setStrokeStyle( material.color.getStyle() );
} else {
var colorStyle1 = element.vertexColors[ 0 ].getStyle();
var colorStyle2 = element.vertexColors[ 1 ].getStyle();
if ( colorStyle1 === colorStyle2 ) {
setStrokeStyle( colorStyle1 );
} else {
try {
var grad = _context.createLinearGradient(
v1.positionScreen.x,
v1.positionScreen.y,
v2.positionScreen.x,
v2.positionScreen.y
);
grad.addColorStop( 0, colorStyle1 );
grad.addColorStop( 1, colorStyle2 );
} catch ( exception ) {
grad = colorStyle1;
}
setStrokeStyle( grad );
}
}
_context.stroke();
_elemBox.expandByScalar( material.linewidth * 2 );
} else if ( material instanceof THREE.LineDashedMaterial ) {
setLineWidth( material.linewidth );
setLineCap( material.linecap );
setLineJoin( material.linejoin );
setStrokeStyle( material.color.getStyle() );
setLineDash( [ material.dashSize, material.gapSize ] );
_context.stroke();
_elemBox.expandByScalar( material.linewidth * 2 );
setLineDash( [] );
}
}
function renderFace3( v1, v2, v3, uv1, uv2, uv3, element, material ) {
_this.info.render.vertices += 3;
_this.info.render.faces ++;
setOpacity( material.opacity );
setBlending( material.blending );
_v1x = v1.positionScreen.x; _v1y = v1.positionScreen.y;
_v2x = v2.positionScreen.x; _v2y = v2.positionScreen.y;
_v3x = v3.positionScreen.x; _v3y = v3.positionScreen.y;
drawTriangle( _v1x, _v1y, _v2x, _v2y, _v3x, _v3y );
if ( ( material instanceof THREE.MeshLambertMaterial || material instanceof THREE.MeshPhongMaterial ) && material.map === null ) {
_diffuseColor.copy( material.color );
_emissiveColor.copy( material.emissive );
if ( material.vertexColors === THREE.FaceColors ) {
_diffuseColor.multiply( element.color );
}
_color.copy( _ambientLight );
_centroid.copy( v1.positionWorld ).add( v2.positionWorld ).add( v3.positionWorld ).divideScalar( 3 );
calculateLight( _centroid, element.normalModel, _color );
_color.multiply( _diffuseColor ).add( _emissiveColor );
material.wireframe === true
? strokePath( _color, material.wireframeLinewidth, material.wireframeLinecap, material.wireframeLinejoin )
: fillPath( _color );
} else if ( material instanceof THREE.MeshBasicMaterial ||
material instanceof THREE.MeshLambertMaterial ||
material instanceof THREE.MeshPhongMaterial ) {
if ( material.map !== null ) {
var mapping = material.map.mapping;
if ( mapping === THREE.UVMapping ) {
_uvs = element.uvs;
patternPath( _v1x, _v1y, _v2x, _v2y, _v3x, _v3y, _uvs[ uv1 ].x, _uvs[ uv1 ].y, _uvs[ uv2 ].x, _uvs[ uv2 ].y, _uvs[ uv3 ].x, _uvs[ uv3 ].y, material.map );
}
} else if ( material.envMap !== null ) {
if ( material.envMap.mapping === THREE.SphericalReflectionMapping ) {
_normal.copy( element.vertexNormalsModel[ uv1 ] ).applyMatrix3( _normalViewMatrix );
_uv1x = 0.5 * _normal.x + 0.5;
_uv1y = 0.5 * _normal.y + 0.5;
_normal.copy( element.vertexNormalsModel[ uv2 ] ).applyMatrix3( _normalViewMatrix );
_uv2x = 0.5 * _normal.x + 0.5;
_uv2y = 0.5 * _normal.y + 0.5;
_normal.copy( element.vertexNormalsModel[ uv3 ] ).applyMatrix3( _normalViewMatrix );
_uv3x = 0.5 * _normal.x + 0.5;
_uv3y = 0.5 * _normal.y + 0.5;
patternPath( _v1x, _v1y, _v2x, _v2y, _v3x, _v3y, _uv1x, _uv1y, _uv2x, _uv2y, _uv3x, _uv3y, material.envMap );
}
} else {
_color.copy( material.color );
if ( material.vertexColors === THREE.FaceColors ) {
_color.multiply( element.color );
}
material.wireframe === true
? strokePath( _color, material.wireframeLinewidth, material.wireframeLinecap, material.wireframeLinejoin )
: fillPath( _color );
}
} else if ( material instanceof THREE.MeshDepthMaterial ) {
_color.r = _color.g = _color.b = 1 - smoothstep( v1.positionScreen.z * v1.positionScreen.w, _camera.near, _camera.far );
material.wireframe === true
? strokePath( _color, material.wireframeLinewidth, material.wireframeLinecap, material.wireframeLinejoin )
: fillPath( _color );
} else if ( material instanceof THREE.MeshNormalMaterial ) {
_normal.copy( element.normalModel ).applyMatrix3( _normalViewMatrix );
_color.setRGB( _normal.x, _normal.y, _normal.z ).multiplyScalar( 0.5 ).addScalar( 0.5 );
material.wireframe === true
? strokePath( _color, material.wireframeLinewidth, material.wireframeLinecap, material.wireframeLinejoin )
: fillPath( _color );
} else {
_color.setRGB( 1, 1, 1 );
material.wireframe === true
? strokePath( _color, material.wireframeLinewidth, material.wireframeLinecap, material.wireframeLinejoin )
: fillPath( _color );
}
}
//
function drawTriangle( x0, y0, x1, y1, x2, y2 ) {
_context.beginPath();
_context.moveTo( x0, y0 );
_context.lineTo( x1, y1 );
_context.lineTo( x2, y2 );
_context.closePath();
}
function strokePath( color, linewidth, linecap, linejoin ) {
setLineWidth( linewidth );
setLineCap( linecap );
setLineJoin( linejoin );
setStrokeStyle( color.getStyle() );
_context.stroke();
_elemBox.expandByScalar( linewidth * 2 );
}
function fillPath( color ) {
setFillStyle( color.getStyle() );
_context.fill();
}
function onTextureUpdate ( event ) {
textureToPattern( event.target );
}
function textureToPattern( texture ) {
if ( texture instanceof THREE.CompressedTexture ) return;
var repeatX = texture.wrapS === THREE.RepeatWrapping;
var repeatY = texture.wrapT === THREE.RepeatWrapping;
var image = texture.image;
var canvas = document.createElement( 'canvas' );
canvas.width = image.width;
canvas.height = image.height;
var context = canvas.getContext( '2d' );
context.setTransform( 1, 0, 0, - 1, 0, image.height );
context.drawImage( image, 0, 0 );
_patterns[ texture.id ] = _context.createPattern(
canvas, repeatX === true && repeatY === true
? 'repeat'
: repeatX === true && repeatY === false
? 'repeat-x'
: repeatX === false && repeatY === true
? 'repeat-y'
: 'no-repeat'
);
}
function patternPath( x0, y0, x1, y1, x2, y2, u0, v0, u1, v1, u2, v2, texture ) {
if ( texture instanceof THREE.DataTexture ) return;
if ( texture.hasEventListener( 'update', onTextureUpdate ) === false ) {
if ( texture.image !== undefined && texture.image.width > 0 ) {
textureToPattern( texture );
}
texture.addEventListener( 'update', onTextureUpdate );
}
var pattern = _patterns[ texture.id ];
if ( pattern !== undefined ) {
setFillStyle( pattern );
} else {
setFillStyle( 'rgba(0,0,0,1)' );
_context.fill();
return;
}
// http://extremelysatisfactorytotalitarianism.com/blog/?p=2120
var a, b, c, d, e, f, det, idet,
offsetX = texture.offset.x / texture.repeat.x,
offsetY = texture.offset.y / texture.repeat.y,
width = texture.image.width * texture.repeat.x,
height = texture.image.height * texture.repeat.y;
u0 = ( u0 + offsetX ) * width;
v0 = ( v0 + offsetY ) * height;
u1 = ( u1 + offsetX ) * width;
v1 = ( v1 + offsetY ) * height;
u2 = ( u2 + offsetX ) * width;
v2 = ( v2 + offsetY ) * height;
x1 -= x0; y1 -= y0;
x2 -= x0; y2 -= y0;
u1 -= u0; v1 -= v0;
u2 -= u0; v2 -= v0;
det = u1 * v2 - u2 * v1;
if ( det === 0 ) return;
idet = 1 / det;
a = ( v2 * x1 - v1 * x2 ) * idet;
b = ( v2 * y1 - v1 * y2 ) * idet;
c = ( u1 * x2 - u2 * x1 ) * idet;
d = ( u1 * y2 - u2 * y1 ) * idet;
e = x0 - a * u0 - c * v0;
f = y0 - b * u0 - d * v0;
_context.save();
_context.transform( a, b, c, d, e, f );
_context.fill();
_context.restore();
}
function clipImage( x0, y0, x1, y1, x2, y2, u0, v0, u1, v1, u2, v2, image ) {
// http://extremelysatisfactorytotalitarianism.com/blog/?p=2120
var a, b, c, d, e, f, det, idet,
width = image.width - 1,
height = image.height - 1;
u0 *= width; v0 *= height;
u1 *= width; v1 *= height;
u2 *= width; v2 *= height;
x1 -= x0; y1 -= y0;
x2 -= x0; y2 -= y0;
u1 -= u0; v1 -= v0;
u2 -= u0; v2 -= v0;
det = u1 * v2 - u2 * v1;
idet = 1 / det;
a = ( v2 * x1 - v1 * x2 ) * idet;
b = ( v2 * y1 - v1 * y2 ) * idet;
c = ( u1 * x2 - u2 * x1 ) * idet;
d = ( u1 * y2 - u2 * y1 ) * idet;
e = x0 - a * u0 - c * v0;
f = y0 - b * u0 - d * v0;
_context.save();
_context.transform( a, b, c, d, e, f );
_context.clip();
_context.drawImage( image, 0, 0 );
_context.restore();
}
// Hide anti-alias gaps
function expand( v1, v2, pixels ) {
var x = v2.x - v1.x, y = v2.y - v1.y,
det = x * x + y * y, idet;
if ( det === 0 ) return;
idet = pixels / Math.sqrt( det );
x *= idet; y *= idet;
v2.x += x; v2.y += y;
v1.x -= x; v1.y -= y;
}
// Context cached methods.
function setOpacity( value ) {
if ( _contextGlobalAlpha !== value ) {
_context.globalAlpha = value;
_contextGlobalAlpha = value;
}
}
function setBlending( value ) {
if ( _contextGlobalCompositeOperation !== value ) {
if ( value === THREE.NormalBlending ) {
_context.globalCompositeOperation = 'source-over';
} else if ( value === THREE.AdditiveBlending ) {
_context.globalCompositeOperation = 'lighter';
} else if ( value === THREE.SubtractiveBlending ) {
_context.globalCompositeOperation = 'darker';
}
_contextGlobalCompositeOperation = value;
}
}
function setLineWidth( value ) {
if ( _contextLineWidth !== value ) {
_context.lineWidth = value;
_contextLineWidth = value;
}
}
function setLineCap( value ) {
// "butt", "round", "square"
if ( _contextLineCap !== value ) {
_context.lineCap = value;
_contextLineCap = value;
}
}
function setLineJoin( value ) {
// "round", "bevel", "miter"
if ( _contextLineJoin !== value ) {
_context.lineJoin = value;
_contextLineJoin = value;
}
}
function setStrokeStyle( value ) {
if ( _contextStrokeStyle !== value ) {
_context.strokeStyle = value;
_contextStrokeStyle = value;
}
}
function setFillStyle( value ) {
if ( _contextFillStyle !== value ) {
_context.fillStyle = value;
_contextFillStyle = value;
}
}
function setLineDash( value ) {
if ( _contextLineDash.length !== value.length ) {
_context.setLineDash( value );
_contextLineDash = value;
}
}
};
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