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Projector.js
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Projector.js
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/**
* @author mrdoob / http://mrdoob.com/
* @author supereggbert / http://www.paulbrunt.co.uk/
* @author julianwa / https://github.com/julianwa
*/
THREE.RenderableObject = function () {
this.id = 0;
this.object = null;
this.z = 0;
this.renderOrder = 0;
};
//
THREE.RenderableFace = function () {
this.id = 0;
this.v1 = new THREE.RenderableVertex();
this.v2 = new THREE.RenderableVertex();
this.v3 = new THREE.RenderableVertex();
this.normalModel = new THREE.Vector3();
this.vertexNormalsModel = [ new THREE.Vector3(), new THREE.Vector3(), new THREE.Vector3() ];
this.vertexNormalsLength = 0;
this.color = new THREE.Color();
this.material = null;
this.uvs = [ new THREE.Vector2(), new THREE.Vector2(), new THREE.Vector2() ];
this.z = 0;
this.renderOrder = 0;
};
//
THREE.RenderableVertex = function () {
this.position = new THREE.Vector3();
this.positionWorld = new THREE.Vector3();
this.positionScreen = new THREE.Vector4();
this.visible = true;
};
THREE.RenderableVertex.prototype.copy = function ( vertex ) {
this.positionWorld.copy( vertex.positionWorld );
this.positionScreen.copy( vertex.positionScreen );
};
//
THREE.RenderableLine = function () {
this.id = 0;
this.v1 = new THREE.RenderableVertex();
this.v2 = new THREE.RenderableVertex();
this.vertexColors = [ new THREE.Color(), new THREE.Color() ];
this.material = null;
this.z = 0;
this.renderOrder = 0;
};
//
THREE.RenderableSprite = function () {
this.id = 0;
this.object = null;
this.x = 0;
this.y = 0;
this.z = 0;
this.rotation = 0;
this.scale = new THREE.Vector2();
this.material = null;
this.renderOrder = 0;
};
//
THREE.Projector = function () {
var _object, _objectCount, _objectPool = [], _objectPoolLength = 0,
_vertex, _vertexCount, _vertexPool = [], _vertexPoolLength = 0,
_face, _faceCount, _facePool = [], _facePoolLength = 0,
_line, _lineCount, _linePool = [], _linePoolLength = 0,
_sprite, _spriteCount, _spritePool = [], _spritePoolLength = 0,
_renderData = { objects: [], lights: [], elements: [] },
_vector3 = new THREE.Vector3(),
_vector4 = new THREE.Vector4(),
_clipBox = new THREE.Box3( new THREE.Vector3( - 1, - 1, - 1 ), new THREE.Vector3( 1, 1, 1 ) ),
_boundingBox = new THREE.Box3(),
_points3 = new Array( 3 ),
_points4 = new Array( 4 ),
_viewMatrix = new THREE.Matrix4(),
_viewProjectionMatrix = new THREE.Matrix4(),
_modelMatrix,
_modelViewProjectionMatrix = new THREE.Matrix4(),
_normalMatrix = new THREE.Matrix3(),
_frustum = new THREE.Frustum(),
_clippedVertex1PositionScreen = new THREE.Vector4(),
_clippedVertex2PositionScreen = new THREE.Vector4();
//
this.projectVector = function ( vector, camera ) {
console.warn( 'THREE.Projector: .projectVector() is now vector.project().' );
vector.project( camera );
};
this.unprojectVector = function ( vector, camera ) {
console.warn( 'THREE.Projector: .unprojectVector() is now vector.unproject().' );
vector.unproject( camera );
};
this.pickingRay = function ( vector, camera ) {
console.error( 'THREE.Projector: .pickingRay() is now raycaster.setFromCamera().' );
};
//
var RenderList = function () {
var normals = [];
var uvs = [];
var object = null;
var material = null;
var normalMatrix = new THREE.Matrix3();
var setObject = function ( value ) {
object = value;
material = object.material;
normalMatrix.getNormalMatrix( object.matrixWorld );
normals.length = 0;
uvs.length = 0;
};
var projectVertex = function ( vertex ) {
var position = vertex.position;
var positionWorld = vertex.positionWorld;
var positionScreen = vertex.positionScreen;
positionWorld.copy( position ).applyMatrix4( _modelMatrix );
positionScreen.copy( positionWorld ).applyMatrix4( _viewProjectionMatrix );
var invW = 1 / positionScreen.w;
positionScreen.x *= invW;
positionScreen.y *= invW;
positionScreen.z *= invW;
vertex.visible = positionScreen.x >= - 1 && positionScreen.x <= 1 &&
positionScreen.y >= - 1 && positionScreen.y <= 1 &&
positionScreen.z >= - 1 && positionScreen.z <= 1;
};
var pushVertex = function ( x, y, z ) {
_vertex = getNextVertexInPool();
_vertex.position.set( x, y, z );
projectVertex( _vertex );
};
var pushNormal = function ( x, y, z ) {
normals.push( x, y, z );
};
var pushUv = function ( x, y ) {
uvs.push( x, y );
};
var checkTriangleVisibility = function ( v1, v2, v3 ) {
if ( v1.visible === true || v2.visible === true || v3.visible === true ) return true;
_points3[ 0 ] = v1.positionScreen;
_points3[ 1 ] = v2.positionScreen;
_points3[ 2 ] = v3.positionScreen;
return _clipBox.isIntersectionBox( _boundingBox.setFromPoints( _points3 ) );
};
var checkBackfaceCulling = function ( v1, v2, v3 ) {
return ( ( v3.positionScreen.x - v1.positionScreen.x ) *
( v2.positionScreen.y - v1.positionScreen.y ) -
( v3.positionScreen.y - v1.positionScreen.y ) *
( v2.positionScreen.x - v1.positionScreen.x ) ) < 0;
};
var pushLine = function ( a, b ) {
var v1 = _vertexPool[ a ];
var v2 = _vertexPool[ b ];
_line = getNextLineInPool();
_line.id = object.id;
_line.v1.copy( v1 );
_line.v2.copy( v2 );
_line.z = ( v1.positionScreen.z + v2.positionScreen.z ) / 2;
_line.renderOrder = object.renderOrder;
_line.material = object.material;
_renderData.elements.push( _line );
};
var pushTriangle = function ( a, b, c ) {
var v1 = _vertexPool[ a ];
var v2 = _vertexPool[ b ];
var v3 = _vertexPool[ c ];
if ( checkTriangleVisibility( v1, v2, v3 ) === false ) return;
if ( material.side === THREE.DoubleSide || checkBackfaceCulling( v1, v2, v3 ) === true ) {
_face = getNextFaceInPool();
_face.id = object.id;
_face.v1.copy( v1 );
_face.v2.copy( v2 );
_face.v3.copy( v3 );
_face.z = ( v1.positionScreen.z + v2.positionScreen.z + v3.positionScreen.z ) / 3;
_face.renderOrder = object.renderOrder;
// use first vertex normal as face normal
_face.normalModel.fromArray( normals, a * 3 );
_face.normalModel.applyMatrix3( normalMatrix ).normalize();
for ( var i = 0; i < 3; i ++ ) {
var normal = _face.vertexNormalsModel[ i ];
normal.fromArray( normals, arguments[ i ] * 3 );
normal.applyMatrix3( normalMatrix ).normalize();
var uv = _face.uvs[ i ];
uv.fromArray( uvs, arguments[ i ] * 2 );
}
_face.vertexNormalsLength = 3;
_face.material = object.material;
_renderData.elements.push( _face );
}
};
return {
setObject: setObject,
projectVertex: projectVertex,
checkTriangleVisibility: checkTriangleVisibility,
checkBackfaceCulling: checkBackfaceCulling,
pushVertex: pushVertex,
pushNormal: pushNormal,
pushUv: pushUv,
pushLine: pushLine,
pushTriangle: pushTriangle
}
};
var renderList = new RenderList();
this.projectScene = function ( scene, camera, sortObjects, sortElements ) {
_faceCount = 0;
_lineCount = 0;
_spriteCount = 0;
_renderData.elements.length = 0;
if ( scene.autoUpdate === true ) scene.updateMatrixWorld();
if ( camera.parent === undefined ) camera.updateMatrixWorld();
_viewMatrix.copy( camera.matrixWorldInverse.getInverse( camera.matrixWorld ) );
_viewProjectionMatrix.multiplyMatrices( camera.projectionMatrix, _viewMatrix );
_frustum.setFromMatrix( _viewProjectionMatrix );
//
_objectCount = 0;
_renderData.objects.length = 0;
_renderData.lights.length = 0;
scene.traverseVisible( function ( object ) {
if ( object instanceof THREE.Light ) {
_renderData.lights.push( object );
} else if ( object instanceof THREE.Mesh || object instanceof THREE.Line || object instanceof THREE.Sprite ) {
if ( object.material.visible === false ) return;
if ( object.frustumCulled === false || _frustum.intersectsObject( object ) === true ) {
_object = getNextObjectInPool();
_object.id = object.id;
_object.object = object;
_vector3.setFromMatrixPosition( object.matrixWorld );
_vector3.applyProjection( _viewProjectionMatrix );
_object.z = _vector3.z;
_object.renderOrder = object.renderOrder;
_renderData.objects.push( _object );
}
}
} );
if ( sortObjects === true ) {
_renderData.objects.sort( painterSort );
}
//
for ( var o = 0, ol = _renderData.objects.length; o < ol; o ++ ) {
var object = _renderData.objects[ o ].object;
var geometry = object.geometry;
renderList.setObject( object );
_modelMatrix = object.matrixWorld;
_vertexCount = 0;
if ( object instanceof THREE.Mesh ) {
if ( geometry instanceof THREE.BufferGeometry ) {
var attributes = geometry.attributes;
var offsets = geometry.drawcalls;
if ( attributes.position === undefined ) continue;
var positions = attributes.position.array;
for ( var i = 0, l = positions.length; i < l; i += 3 ) {
renderList.pushVertex( positions[ i ], positions[ i + 1 ], positions[ i + 2 ] );
}
if ( attributes.normal !== undefined ) {
var normals = attributes.normal.array;
for ( var i = 0, l = normals.length; i < l; i += 3 ) {
renderList.pushNormal( normals[ i ], normals[ i + 1 ], normals[ i + 2 ] );
}
}
if ( attributes.uv !== undefined ) {
var uvs = attributes.uv.array;
for ( var i = 0, l = uvs.length; i < l; i += 2 ) {
renderList.pushUv( uvs[ i ], uvs[ i + 1 ] );
}
}
if ( attributes.index !== undefined ) {
var indices = attributes.index.array;
if ( offsets.length > 0 ) {
for ( var o = 0; o < offsets.length; o ++ ) {
var offset = offsets[ o ];
var index = offset.index;
for ( var i = offset.start, l = offset.start + offset.count; i < l; i += 3 ) {
renderList.pushTriangle( indices[ i ] + index, indices[ i + 1 ] + index, indices[ i + 2 ] + index );
}
}
} else {
for ( var i = 0, l = indices.length; i < l; i += 3 ) {
renderList.pushTriangle( indices[ i ], indices[ i + 1 ], indices[ i + 2 ] );
}
}
} else {
for ( var i = 0, l = positions.length / 3; i < l; i += 3 ) {
renderList.pushTriangle( i, i + 1, i + 2 );
}
}
} else if ( geometry instanceof THREE.Geometry ) {
var vertices = geometry.vertices;
var faces = geometry.faces;
var faceVertexUvs = geometry.faceVertexUvs[ 0 ];
_normalMatrix.getNormalMatrix( _modelMatrix );
var material = object.material;
var isFaceMaterial = material instanceof THREE.MeshFaceMaterial;
var objectMaterials = isFaceMaterial === true ? object.material : null;
for ( var v = 0, vl = vertices.length; v < vl; v ++ ) {
var vertex = vertices[ v ];
_vector3.copy( vertex );
if ( material.morphTargets === true ) {
var morphTargets = geometry.morphTargets;
var morphInfluences = object.morphTargetInfluences;
for ( var t = 0, tl = morphTargets.length; t < tl; t ++ ) {
var influence = morphInfluences[ t ];
if ( influence === 0 ) continue;
var target = morphTargets[ t ];
var targetVertex = target.vertices[ v ];
_vector3.x += ( targetVertex.x - vertex.x ) * influence;
_vector3.y += ( targetVertex.y - vertex.y ) * influence;
_vector3.z += ( targetVertex.z - vertex.z ) * influence;
}
}
renderList.pushVertex( _vector3.x, _vector3.y, _vector3.z );
}
for ( var f = 0, fl = faces.length; f < fl; f ++ ) {
var face = faces[ f ];
material = isFaceMaterial === true
? objectMaterials.materials[ face.materialIndex ]
: object.material;
if ( material === undefined ) continue;
var side = material.side;
var v1 = _vertexPool[ face.a ];
var v2 = _vertexPool[ face.b ];
var v3 = _vertexPool[ face.c ];
if ( renderList.checkTriangleVisibility( v1, v2, v3 ) === false ) continue;
var visible = renderList.checkBackfaceCulling( v1, v2, v3 );
if ( side !== THREE.DoubleSide ) {
if ( side === THREE.FrontSide && visible === false ) continue;
if ( side === THREE.BackSide && visible === true ) continue;
}
_face = getNextFaceInPool();
_face.id = object.id;
_face.v1.copy( v1 );
_face.v2.copy( v2 );
_face.v3.copy( v3 );
_face.normalModel.copy( face.normal );
if ( visible === false && ( side === THREE.BackSide || side === THREE.DoubleSide ) ) {
_face.normalModel.negate();
}
_face.normalModel.applyMatrix3( _normalMatrix ).normalize();
var faceVertexNormals = face.vertexNormals;
for ( var n = 0, nl = Math.min( faceVertexNormals.length, 3 ); n < nl; n ++ ) {
var normalModel = _face.vertexNormalsModel[ n ];
normalModel.copy( faceVertexNormals[ n ] );
if ( visible === false && ( side === THREE.BackSide || side === THREE.DoubleSide ) ) {
normalModel.negate();
}
normalModel.applyMatrix3( _normalMatrix ).normalize();
}
_face.vertexNormalsLength = faceVertexNormals.length;
var vertexUvs = faceVertexUvs[ f ];
if ( vertexUvs !== undefined ) {
for ( var u = 0; u < 3; u ++ ) {
_face.uvs[ u ].copy( vertexUvs[ u ] );
}
}
_face.color = face.color;
_face.material = material;
_face.z = ( v1.positionScreen.z + v2.positionScreen.z + v3.positionScreen.z ) / 3;
_face.renderOrder = object.renderOrder;
_renderData.elements.push( _face );
}
}
} else if ( object instanceof THREE.Line ) {
if ( geometry instanceof THREE.BufferGeometry ) {
var attributes = geometry.attributes;
if ( attributes.position !== undefined ) {
var positions = attributes.position.array;
for ( var i = 0, l = positions.length; i < l; i += 3 ) {
renderList.pushVertex( positions[ i ], positions[ i + 1 ], positions[ i + 2 ] );
}
if ( attributes.index !== undefined ) {
var indices = attributes.index.array;
for ( var i = 0, l = indices.length; i < l; i += 2 ) {
renderList.pushLine( indices[ i ], indices[ i + 1 ] );
}
} else {
var step = object instanceof THREE.LineSegments ? 2 : 1;
for ( var i = 0, l = ( positions.length / 3 ) - 1; i < l; i += step ) {
renderList.pushLine( i, i + 1 );
}
}
}
} else if ( geometry instanceof THREE.Geometry ) {
_modelViewProjectionMatrix.multiplyMatrices( _viewProjectionMatrix, _modelMatrix );
var vertices = object.geometry.vertices;
if ( vertices.length === 0 ) continue;
v1 = getNextVertexInPool();
v1.positionScreen.copy( vertices[ 0 ] ).applyMatrix4( _modelViewProjectionMatrix );
var step = object instanceof THREE.LineSegments ? 2 : 1;
for ( var v = 1, vl = vertices.length; v < vl; v ++ ) {
v1 = getNextVertexInPool();
v1.positionScreen.copy( vertices[ v ] ).applyMatrix4( _modelViewProjectionMatrix );
if ( ( v + 1 ) % step > 0 ) continue;
v2 = _vertexPool[ _vertexCount - 2 ];
_clippedVertex1PositionScreen.copy( v1.positionScreen );
_clippedVertex2PositionScreen.copy( v2.positionScreen );
if ( clipLine( _clippedVertex1PositionScreen, _clippedVertex2PositionScreen ) === true ) {
// Perform the perspective divide
_clippedVertex1PositionScreen.multiplyScalar( 1 / _clippedVertex1PositionScreen.w );
_clippedVertex2PositionScreen.multiplyScalar( 1 / _clippedVertex2PositionScreen.w );
_line = getNextLineInPool();
_line.id = object.id;
_line.v1.positionScreen.copy( _clippedVertex1PositionScreen );
_line.v2.positionScreen.copy( _clippedVertex2PositionScreen );
_line.z = Math.max( _clippedVertex1PositionScreen.z, _clippedVertex2PositionScreen.z );
_line.renderOrder = object.renderOrder;
_line.material = object.material;
if ( object.material.vertexColors === THREE.VertexColors ) {
_line.vertexColors[ 0 ].copy( object.geometry.colors[ v ] );
_line.vertexColors[ 1 ].copy( object.geometry.colors[ v - 1 ] );
}
_renderData.elements.push( _line );
}
}
}
} else if ( object instanceof THREE.Sprite ) {
_vector4.set( _modelMatrix.elements[ 12 ], _modelMatrix.elements[ 13 ], _modelMatrix.elements[ 14 ], 1 );
_vector4.applyMatrix4( _viewProjectionMatrix );
var invW = 1 / _vector4.w;
_vector4.z *= invW;
if ( _vector4.z >= - 1 && _vector4.z <= 1 ) {
_sprite = getNextSpriteInPool();
_sprite.id = object.id;
_sprite.x = _vector4.x * invW;
_sprite.y = _vector4.y * invW;
_sprite.z = _vector4.z;
_sprite.renderOrder = object.renderOrder;
_sprite.object = object;
_sprite.rotation = object.rotation;
_sprite.scale.x = object.scale.x * Math.abs( _sprite.x - ( _vector4.x + camera.projectionMatrix.elements[ 0 ] ) / ( _vector4.w + camera.projectionMatrix.elements[ 12 ] ) );
_sprite.scale.y = object.scale.y * Math.abs( _sprite.y - ( _vector4.y + camera.projectionMatrix.elements[ 5 ] ) / ( _vector4.w + camera.projectionMatrix.elements[ 13 ] ) );
_sprite.material = object.material;
_renderData.elements.push( _sprite );
}
}
}
if ( sortElements === true ) {
_renderData.elements.sort( painterSort );
}
return _renderData;
};
// Pools
function getNextObjectInPool() {
if ( _objectCount === _objectPoolLength ) {
var object = new THREE.RenderableObject();
_objectPool.push( object );
_objectPoolLength ++;
_objectCount ++;
return object;
}
return _objectPool[ _objectCount ++ ];
}
function getNextVertexInPool() {
if ( _vertexCount === _vertexPoolLength ) {
var vertex = new THREE.RenderableVertex();
_vertexPool.push( vertex );
_vertexPoolLength ++;
_vertexCount ++;
return vertex;
}
return _vertexPool[ _vertexCount ++ ];
}
function getNextFaceInPool() {
if ( _faceCount === _facePoolLength ) {
var face = new THREE.RenderableFace();
_facePool.push( face );
_facePoolLength ++;
_faceCount ++;
return face;
}
return _facePool[ _faceCount ++ ];
}
function getNextLineInPool() {
if ( _lineCount === _linePoolLength ) {
var line = new THREE.RenderableLine();
_linePool.push( line );
_linePoolLength ++;
_lineCount ++;
return line;
}
return _linePool[ _lineCount ++ ];
}
function getNextSpriteInPool() {
if ( _spriteCount === _spritePoolLength ) {
var sprite = new THREE.RenderableSprite();
_spritePool.push( sprite );
_spritePoolLength ++;
_spriteCount ++;
return sprite;
}
return _spritePool[ _spriteCount ++ ];
}
//
function painterSort( a, b ) {
if ( a.renderOrder !== b.renderOrder ) {
return a.renderOrder - b.renderOrder;
} else if ( a.z !== b.z ) {
return b.z - a.z;
} else if ( a.id !== b.id ) {
return a.id - b.id;
} else {
return 0;
}
}
function clipLine( s1, s2 ) {
var alpha1 = 0, alpha2 = 1,
// Calculate the boundary coordinate of each vertex for the near and far clip planes,
// Z = -1 and Z = +1, respectively.
bc1near = s1.z + s1.w,
bc2near = s2.z + s2.w,
bc1far = - s1.z + s1.w,
bc2far = - s2.z + s2.w;
if ( bc1near >= 0 && bc2near >= 0 && bc1far >= 0 && bc2far >= 0 ) {
// Both vertices lie entirely within all clip planes.
return true;
} else if ( ( bc1near < 0 && bc2near < 0 ) || ( bc1far < 0 && bc2far < 0 ) ) {
// Both vertices lie entirely outside one of the clip planes.
return false;
} else {
// The line segment spans at least one clip plane.
if ( bc1near < 0 ) {
// v1 lies outside the near plane, v2 inside
alpha1 = Math.max( alpha1, bc1near / ( bc1near - bc2near ) );
} else if ( bc2near < 0 ) {
// v2 lies outside the near plane, v1 inside
alpha2 = Math.min( alpha2, bc1near / ( bc1near - bc2near ) );
}
if ( bc1far < 0 ) {
// v1 lies outside the far plane, v2 inside
alpha1 = Math.max( alpha1, bc1far / ( bc1far - bc2far ) );
} else if ( bc2far < 0 ) {
// v2 lies outside the far plane, v2 inside
alpha2 = Math.min( alpha2, bc1far / ( bc1far - bc2far ) );
}
if ( alpha2 < alpha1 ) {
// The line segment spans two boundaries, but is outside both of them.
// (This can't happen when we're only clipping against just near/far but good
// to leave the check here for future usage if other clip planes are added.)
return false;
} else {
// Update the s1 and s2 vertices to match the clipped line segment.
s1.lerp( s2, alpha1 );
s2.lerp( s1, 1 - alpha2 );
return true;
}
}
}
};