Projector.js 19 KB

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  1. import {
  2. Box3,
  3. Color,
  4. DoubleSide,
  5. Frustum,
  6. Matrix3,
  7. Matrix4,
  8. Vector2,
  9. Vector3,
  10. Vector4
  11. } from 'three';
  12. class RenderableObject {
  13. constructor() {
  14. this.id = 0;
  15. this.object = null;
  16. this.z = 0;
  17. this.renderOrder = 0;
  18. }
  19. }
  20. //
  21. class RenderableFace {
  22. constructor() {
  23. this.id = 0;
  24. this.v1 = new RenderableVertex();
  25. this.v2 = new RenderableVertex();
  26. this.v3 = new RenderableVertex();
  27. this.normalModel = new Vector3();
  28. this.vertexNormalsModel = [ new Vector3(), new Vector3(), new Vector3() ];
  29. this.vertexNormalsLength = 0;
  30. this.color = new Color();
  31. this.material = null;
  32. this.uvs = [ new Vector2(), new Vector2(), new Vector2() ];
  33. this.z = 0;
  34. this.renderOrder = 0;
  35. }
  36. }
  37. //
  38. class RenderableVertex {
  39. constructor() {
  40. this.position = new Vector3();
  41. this.positionWorld = new Vector3();
  42. this.positionScreen = new Vector4();
  43. this.visible = true;
  44. }
  45. copy( vertex ) {
  46. this.positionWorld.copy( vertex.positionWorld );
  47. this.positionScreen.copy( vertex.positionScreen );
  48. }
  49. }
  50. //
  51. class RenderableLine {
  52. constructor() {
  53. this.id = 0;
  54. this.v1 = new RenderableVertex();
  55. this.v2 = new RenderableVertex();
  56. this.vertexColors = [ new Color(), new Color() ];
  57. this.material = null;
  58. this.z = 0;
  59. this.renderOrder = 0;
  60. }
  61. }
  62. //
  63. class RenderableSprite {
  64. constructor() {
  65. this.id = 0;
  66. this.object = null;
  67. this.x = 0;
  68. this.y = 0;
  69. this.z = 0;
  70. this.rotation = 0;
  71. this.scale = new Vector2();
  72. this.material = null;
  73. this.renderOrder = 0;
  74. }
  75. }
  76. //
  77. class Projector {
  78. constructor() {
  79. let _object, _objectCount, _objectPoolLength = 0,
  80. _vertex, _vertexCount, _vertexPoolLength = 0,
  81. _face, _faceCount, _facePoolLength = 0,
  82. _line, _lineCount, _linePoolLength = 0,
  83. _sprite, _spriteCount, _spritePoolLength = 0,
  84. _modelMatrix;
  85. const
  86. _renderData = { objects: [], lights: [], elements: [] },
  87. _vector3 = new Vector3(),
  88. _vector4 = new Vector4(),
  89. _clipBox = new Box3( new Vector3( - 1, - 1, - 1 ), new Vector3( 1, 1, 1 ) ),
  90. _boundingBox = new Box3(),
  91. _points3 = new Array( 3 ),
  92. _viewMatrix = new Matrix4(),
  93. _viewProjectionMatrix = new Matrix4(),
  94. _modelViewProjectionMatrix = new Matrix4(),
  95. _frustum = new Frustum(),
  96. _objectPool = [], _vertexPool = [], _facePool = [], _linePool = [], _spritePool = [];
  97. //
  98. function RenderList() {
  99. const normals = [];
  100. const colors = [];
  101. const uvs = [];
  102. let object = null;
  103. const normalMatrix = new Matrix3();
  104. function setObject( value ) {
  105. object = value;
  106. normalMatrix.getNormalMatrix( object.matrixWorld );
  107. normals.length = 0;
  108. colors.length = 0;
  109. uvs.length = 0;
  110. }
  111. function projectVertex( vertex ) {
  112. const position = vertex.position;
  113. const positionWorld = vertex.positionWorld;
  114. const positionScreen = vertex.positionScreen;
  115. positionWorld.copy( position ).applyMatrix4( _modelMatrix );
  116. positionScreen.copy( positionWorld ).applyMatrix4( _viewProjectionMatrix );
  117. const invW = 1 / positionScreen.w;
  118. positionScreen.x *= invW;
  119. positionScreen.y *= invW;
  120. positionScreen.z *= invW;
  121. vertex.visible = positionScreen.x >= - 1 && positionScreen.x <= 1 &&
  122. positionScreen.y >= - 1 && positionScreen.y <= 1 &&
  123. positionScreen.z >= - 1 && positionScreen.z <= 1;
  124. }
  125. function pushVertex( x, y, z ) {
  126. _vertex = getNextVertexInPool();
  127. _vertex.position.set( x, y, z );
  128. projectVertex( _vertex );
  129. }
  130. function pushNormal( x, y, z ) {
  131. normals.push( x, y, z );
  132. }
  133. function pushColor( r, g, b ) {
  134. colors.push( r, g, b );
  135. }
  136. function pushUv( x, y ) {
  137. uvs.push( x, y );
  138. }
  139. function checkTriangleVisibility( v1, v2, v3 ) {
  140. if ( v1.visible === true || v2.visible === true || v3.visible === true ) return true;
  141. _points3[ 0 ] = v1.positionScreen;
  142. _points3[ 1 ] = v2.positionScreen;
  143. _points3[ 2 ] = v3.positionScreen;
  144. return _clipBox.intersectsBox( _boundingBox.setFromPoints( _points3 ) );
  145. }
  146. function checkBackfaceCulling( v1, v2, v3 ) {
  147. return ( ( v3.positionScreen.x - v1.positionScreen.x ) *
  148. ( v2.positionScreen.y - v1.positionScreen.y ) -
  149. ( v3.positionScreen.y - v1.positionScreen.y ) *
  150. ( v2.positionScreen.x - v1.positionScreen.x ) ) < 0;
  151. }
  152. function pushLine( a, b ) {
  153. const v1 = _vertexPool[ a ];
  154. const v2 = _vertexPool[ b ];
  155. // Clip
  156. v1.positionScreen.copy( v1.position ).applyMatrix4( _modelViewProjectionMatrix );
  157. v2.positionScreen.copy( v2.position ).applyMatrix4( _modelViewProjectionMatrix );
  158. if ( clipLine( v1.positionScreen, v2.positionScreen ) === true ) {
  159. // Perform the perspective divide
  160. v1.positionScreen.multiplyScalar( 1 / v1.positionScreen.w );
  161. v2.positionScreen.multiplyScalar( 1 / v2.positionScreen.w );
  162. _line = getNextLineInPool();
  163. _line.id = object.id;
  164. _line.v1.copy( v1 );
  165. _line.v2.copy( v2 );
  166. _line.z = Math.max( v1.positionScreen.z, v2.positionScreen.z );
  167. _line.renderOrder = object.renderOrder;
  168. _line.material = object.material;
  169. if ( object.material.vertexColors ) {
  170. _line.vertexColors[ 0 ].fromArray( colors, a * 3 );
  171. _line.vertexColors[ 1 ].fromArray( colors, b * 3 );
  172. }
  173. _renderData.elements.push( _line );
  174. }
  175. }
  176. function pushTriangle( a, b, c, material ) {
  177. const v1 = _vertexPool[ a ];
  178. const v2 = _vertexPool[ b ];
  179. const v3 = _vertexPool[ c ];
  180. if ( checkTriangleVisibility( v1, v2, v3 ) === false ) return;
  181. if ( material.side === DoubleSide || checkBackfaceCulling( v1, v2, v3 ) === true ) {
  182. _face = getNextFaceInPool();
  183. _face.id = object.id;
  184. _face.v1.copy( v1 );
  185. _face.v2.copy( v2 );
  186. _face.v3.copy( v3 );
  187. _face.z = ( v1.positionScreen.z + v2.positionScreen.z + v3.positionScreen.z ) / 3;
  188. _face.renderOrder = object.renderOrder;
  189. // face normal
  190. _vector3.subVectors( v3.position, v2.position );
  191. _vector4.subVectors( v1.position, v2.position );
  192. _vector3.cross( _vector4 );
  193. _face.normalModel.copy( _vector3 );
  194. _face.normalModel.applyMatrix3( normalMatrix ).normalize();
  195. for ( let i = 0; i < 3; i ++ ) {
  196. const normal = _face.vertexNormalsModel[ i ];
  197. normal.fromArray( normals, arguments[ i ] * 3 );
  198. normal.applyMatrix3( normalMatrix ).normalize();
  199. const uv = _face.uvs[ i ];
  200. uv.fromArray( uvs, arguments[ i ] * 2 );
  201. }
  202. _face.vertexNormalsLength = 3;
  203. _face.material = material;
  204. if ( material.vertexColors ) {
  205. _face.color.fromArray( colors, a * 3 );
  206. }
  207. _renderData.elements.push( _face );
  208. }
  209. }
  210. return {
  211. setObject: setObject,
  212. projectVertex: projectVertex,
  213. checkTriangleVisibility: checkTriangleVisibility,
  214. checkBackfaceCulling: checkBackfaceCulling,
  215. pushVertex: pushVertex,
  216. pushNormal: pushNormal,
  217. pushColor: pushColor,
  218. pushUv: pushUv,
  219. pushLine: pushLine,
  220. pushTriangle: pushTriangle
  221. };
  222. }
  223. const renderList = new RenderList();
  224. function projectObject( object ) {
  225. if ( object.visible === false ) return;
  226. if ( object.isLight ) {
  227. _renderData.lights.push( object );
  228. } else if ( object.isMesh || object.isLine || object.isPoints ) {
  229. if ( object.material.visible === false ) return;
  230. if ( object.frustumCulled === true && _frustum.intersectsObject( object ) === false ) return;
  231. addObject( object );
  232. } else if ( object.isSprite ) {
  233. if ( object.material.visible === false ) return;
  234. if ( object.frustumCulled === true && _frustum.intersectsSprite( object ) === false ) return;
  235. addObject( object );
  236. }
  237. const children = object.children;
  238. for ( let i = 0, l = children.length; i < l; i ++ ) {
  239. projectObject( children[ i ] );
  240. }
  241. }
  242. function addObject( object ) {
  243. _object = getNextObjectInPool();
  244. _object.id = object.id;
  245. _object.object = object;
  246. _vector3.setFromMatrixPosition( object.matrixWorld );
  247. _vector3.applyMatrix4( _viewProjectionMatrix );
  248. _object.z = _vector3.z;
  249. _object.renderOrder = object.renderOrder;
  250. _renderData.objects.push( _object );
  251. }
  252. this.projectScene = function ( scene, camera, sortObjects, sortElements ) {
  253. _faceCount = 0;
  254. _lineCount = 0;
  255. _spriteCount = 0;
  256. _renderData.elements.length = 0;
  257. if ( scene.matrixWorldAutoUpdate === true ) scene.updateMatrixWorld();
  258. if ( camera.parent === null && camera.matrixWorldAutoUpdate === true ) camera.updateMatrixWorld();
  259. _viewMatrix.copy( camera.matrixWorldInverse );
  260. _viewProjectionMatrix.multiplyMatrices( camera.projectionMatrix, _viewMatrix );
  261. _frustum.setFromProjectionMatrix( _viewProjectionMatrix );
  262. //
  263. _objectCount = 0;
  264. _renderData.objects.length = 0;
  265. _renderData.lights.length = 0;
  266. projectObject( scene );
  267. if ( sortObjects === true ) {
  268. _renderData.objects.sort( painterSort );
  269. }
  270. //
  271. const objects = _renderData.objects;
  272. for ( let o = 0, ol = objects.length; o < ol; o ++ ) {
  273. const object = objects[ o ].object;
  274. const geometry = object.geometry;
  275. renderList.setObject( object );
  276. _modelMatrix = object.matrixWorld;
  277. _vertexCount = 0;
  278. if ( object.isMesh ) {
  279. let material = object.material;
  280. const isMultiMaterial = Array.isArray( material );
  281. const attributes = geometry.attributes;
  282. const groups = geometry.groups;
  283. if ( attributes.position === undefined ) continue;
  284. const positions = attributes.position.array;
  285. for ( let i = 0, l = positions.length; i < l; i += 3 ) {
  286. let x = positions[ i ];
  287. let y = positions[ i + 1 ];
  288. let z = positions[ i + 2 ];
  289. const morphTargets = geometry.morphAttributes.position;
  290. if ( morphTargets !== undefined ) {
  291. const morphTargetsRelative = geometry.morphTargetsRelative;
  292. const morphInfluences = object.morphTargetInfluences;
  293. for ( let t = 0, tl = morphTargets.length; t < tl; t ++ ) {
  294. const influence = morphInfluences[ t ];
  295. if ( influence === 0 ) continue;
  296. const target = morphTargets[ t ];
  297. if ( morphTargetsRelative ) {
  298. x += target.getX( i / 3 ) * influence;
  299. y += target.getY( i / 3 ) * influence;
  300. z += target.getZ( i / 3 ) * influence;
  301. } else {
  302. x += ( target.getX( i / 3 ) - positions[ i ] ) * influence;
  303. y += ( target.getY( i / 3 ) - positions[ i + 1 ] ) * influence;
  304. z += ( target.getZ( i / 3 ) - positions[ i + 2 ] ) * influence;
  305. }
  306. }
  307. }
  308. renderList.pushVertex( x, y, z );
  309. }
  310. if ( attributes.normal !== undefined ) {
  311. const normals = attributes.normal.array;
  312. for ( let i = 0, l = normals.length; i < l; i += 3 ) {
  313. renderList.pushNormal( normals[ i ], normals[ i + 1 ], normals[ i + 2 ] );
  314. }
  315. }
  316. if ( attributes.color !== undefined ) {
  317. const colors = attributes.color.array;
  318. for ( let i = 0, l = colors.length; i < l; i += 3 ) {
  319. renderList.pushColor( colors[ i ], colors[ i + 1 ], colors[ i + 2 ] );
  320. }
  321. }
  322. if ( attributes.uv !== undefined ) {
  323. const uvs = attributes.uv.array;
  324. for ( let i = 0, l = uvs.length; i < l; i += 2 ) {
  325. renderList.pushUv( uvs[ i ], uvs[ i + 1 ] );
  326. }
  327. }
  328. if ( geometry.index !== null ) {
  329. const indices = geometry.index.array;
  330. if ( groups.length > 0 ) {
  331. for ( let g = 0; g < groups.length; g ++ ) {
  332. const group = groups[ g ];
  333. material = isMultiMaterial === true
  334. ? object.material[ group.materialIndex ]
  335. : object.material;
  336. if ( material === undefined ) continue;
  337. for ( let i = group.start, l = group.start + group.count; i < l; i += 3 ) {
  338. renderList.pushTriangle( indices[ i ], indices[ i + 1 ], indices[ i + 2 ], material );
  339. }
  340. }
  341. } else {
  342. for ( let i = 0, l = indices.length; i < l; i += 3 ) {
  343. renderList.pushTriangle( indices[ i ], indices[ i + 1 ], indices[ i + 2 ], material );
  344. }
  345. }
  346. } else {
  347. if ( groups.length > 0 ) {
  348. for ( let g = 0; g < groups.length; g ++ ) {
  349. const group = groups[ g ];
  350. material = isMultiMaterial === true
  351. ? object.material[ group.materialIndex ]
  352. : object.material;
  353. if ( material === undefined ) continue;
  354. for ( let i = group.start, l = group.start + group.count; i < l; i += 3 ) {
  355. renderList.pushTriangle( i, i + 1, i + 2, material );
  356. }
  357. }
  358. } else {
  359. for ( let i = 0, l = positions.length / 3; i < l; i += 3 ) {
  360. renderList.pushTriangle( i, i + 1, i + 2, material );
  361. }
  362. }
  363. }
  364. } else if ( object.isLine ) {
  365. _modelViewProjectionMatrix.multiplyMatrices( _viewProjectionMatrix, _modelMatrix );
  366. const attributes = geometry.attributes;
  367. if ( attributes.position !== undefined ) {
  368. const positions = attributes.position.array;
  369. for ( let i = 0, l = positions.length; i < l; i += 3 ) {
  370. renderList.pushVertex( positions[ i ], positions[ i + 1 ], positions[ i + 2 ] );
  371. }
  372. if ( attributes.color !== undefined ) {
  373. const colors = attributes.color.array;
  374. for ( let i = 0, l = colors.length; i < l; i += 3 ) {
  375. renderList.pushColor( colors[ i ], colors[ i + 1 ], colors[ i + 2 ] );
  376. }
  377. }
  378. if ( geometry.index !== null ) {
  379. const indices = geometry.index.array;
  380. for ( let i = 0, l = indices.length; i < l; i += 2 ) {
  381. renderList.pushLine( indices[ i ], indices[ i + 1 ] );
  382. }
  383. } else {
  384. const step = object.isLineSegments ? 2 : 1;
  385. for ( let i = 0, l = ( positions.length / 3 ) - 1; i < l; i += step ) {
  386. renderList.pushLine( i, i + 1 );
  387. }
  388. }
  389. }
  390. } else if ( object.isPoints ) {
  391. _modelViewProjectionMatrix.multiplyMatrices( _viewProjectionMatrix, _modelMatrix );
  392. const attributes = geometry.attributes;
  393. if ( attributes.position !== undefined ) {
  394. const positions = attributes.position.array;
  395. for ( let i = 0, l = positions.length; i < l; i += 3 ) {
  396. _vector4.set( positions[ i ], positions[ i + 1 ], positions[ i + 2 ], 1 );
  397. _vector4.applyMatrix4( _modelViewProjectionMatrix );
  398. pushPoint( _vector4, object, camera );
  399. }
  400. }
  401. } else if ( object.isSprite ) {
  402. object.modelViewMatrix.multiplyMatrices( camera.matrixWorldInverse, object.matrixWorld );
  403. _vector4.set( _modelMatrix.elements[ 12 ], _modelMatrix.elements[ 13 ], _modelMatrix.elements[ 14 ], 1 );
  404. _vector4.applyMatrix4( _viewProjectionMatrix );
  405. pushPoint( _vector4, object, camera );
  406. }
  407. }
  408. if ( sortElements === true ) {
  409. _renderData.elements.sort( painterSort );
  410. }
  411. return _renderData;
  412. };
  413. function pushPoint( _vector4, object, camera ) {
  414. const invW = 1 / _vector4.w;
  415. _vector4.z *= invW;
  416. if ( _vector4.z >= - 1 && _vector4.z <= 1 ) {
  417. _sprite = getNextSpriteInPool();
  418. _sprite.id = object.id;
  419. _sprite.x = _vector4.x * invW;
  420. _sprite.y = _vector4.y * invW;
  421. _sprite.z = _vector4.z;
  422. _sprite.renderOrder = object.renderOrder;
  423. _sprite.object = object;
  424. _sprite.rotation = object.rotation;
  425. _sprite.scale.x = object.scale.x * Math.abs( _sprite.x - ( _vector4.x + camera.projectionMatrix.elements[ 0 ] ) / ( _vector4.w + camera.projectionMatrix.elements[ 12 ] ) );
  426. _sprite.scale.y = object.scale.y * Math.abs( _sprite.y - ( _vector4.y + camera.projectionMatrix.elements[ 5 ] ) / ( _vector4.w + camera.projectionMatrix.elements[ 13 ] ) );
  427. _sprite.material = object.material;
  428. _renderData.elements.push( _sprite );
  429. }
  430. }
  431. // Pools
  432. function getNextObjectInPool() {
  433. if ( _objectCount === _objectPoolLength ) {
  434. const object = new RenderableObject();
  435. _objectPool.push( object );
  436. _objectPoolLength ++;
  437. _objectCount ++;
  438. return object;
  439. }
  440. return _objectPool[ _objectCount ++ ];
  441. }
  442. function getNextVertexInPool() {
  443. if ( _vertexCount === _vertexPoolLength ) {
  444. const vertex = new RenderableVertex();
  445. _vertexPool.push( vertex );
  446. _vertexPoolLength ++;
  447. _vertexCount ++;
  448. return vertex;
  449. }
  450. return _vertexPool[ _vertexCount ++ ];
  451. }
  452. function getNextFaceInPool() {
  453. if ( _faceCount === _facePoolLength ) {
  454. const face = new RenderableFace();
  455. _facePool.push( face );
  456. _facePoolLength ++;
  457. _faceCount ++;
  458. return face;
  459. }
  460. return _facePool[ _faceCount ++ ];
  461. }
  462. function getNextLineInPool() {
  463. if ( _lineCount === _linePoolLength ) {
  464. const line = new RenderableLine();
  465. _linePool.push( line );
  466. _linePoolLength ++;
  467. _lineCount ++;
  468. return line;
  469. }
  470. return _linePool[ _lineCount ++ ];
  471. }
  472. function getNextSpriteInPool() {
  473. if ( _spriteCount === _spritePoolLength ) {
  474. const sprite = new RenderableSprite();
  475. _spritePool.push( sprite );
  476. _spritePoolLength ++;
  477. _spriteCount ++;
  478. return sprite;
  479. }
  480. return _spritePool[ _spriteCount ++ ];
  481. }
  482. //
  483. function painterSort( a, b ) {
  484. if ( a.renderOrder !== b.renderOrder ) {
  485. return a.renderOrder - b.renderOrder;
  486. } else if ( a.z !== b.z ) {
  487. return b.z - a.z;
  488. } else if ( a.id !== b.id ) {
  489. return a.id - b.id;
  490. } else {
  491. return 0;
  492. }
  493. }
  494. function clipLine( s1, s2 ) {
  495. let alpha1 = 0, alpha2 = 1;
  496. // Calculate the boundary coordinate of each vertex for the near and far clip planes,
  497. // Z = -1 and Z = +1, respectively.
  498. const bc1near = s1.z + s1.w,
  499. bc2near = s2.z + s2.w,
  500. bc1far = - s1.z + s1.w,
  501. bc2far = - s2.z + s2.w;
  502. if ( bc1near >= 0 && bc2near >= 0 && bc1far >= 0 && bc2far >= 0 ) {
  503. // Both vertices lie entirely within all clip planes.
  504. return true;
  505. } else if ( ( bc1near < 0 && bc2near < 0 ) || ( bc1far < 0 && bc2far < 0 ) ) {
  506. // Both vertices lie entirely outside one of the clip planes.
  507. return false;
  508. } else {
  509. // The line segment spans at least one clip plane.
  510. if ( bc1near < 0 ) {
  511. // v1 lies outside the near plane, v2 inside
  512. alpha1 = Math.max( alpha1, bc1near / ( bc1near - bc2near ) );
  513. } else if ( bc2near < 0 ) {
  514. // v2 lies outside the near plane, v1 inside
  515. alpha2 = Math.min( alpha2, bc1near / ( bc1near - bc2near ) );
  516. }
  517. if ( bc1far < 0 ) {
  518. // v1 lies outside the far plane, v2 inside
  519. alpha1 = Math.max( alpha1, bc1far / ( bc1far - bc2far ) );
  520. } else if ( bc2far < 0 ) {
  521. // v2 lies outside the far plane, v2 inside
  522. alpha2 = Math.min( alpha2, bc1far / ( bc1far - bc2far ) );
  523. }
  524. if ( alpha2 < alpha1 ) {
  525. // The line segment spans two boundaries, but is outside both of them.
  526. // (This can't happen when we're only clipping against just near/far but good
  527. // to leave the check here for future usage if other clip planes are added.)
  528. return false;
  529. } else {
  530. // Update the s1 and s2 vertices to match the clipped line segment.
  531. s1.lerp( s2, alpha1 );
  532. s2.lerp( s1, 1 - alpha2 );
  533. return true;
  534. }
  535. }
  536. }
  537. }
  538. }
  539. export { RenderableObject, RenderableFace, RenderableVertex, RenderableLine, RenderableSprite, Projector };