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 '../../../build/three.module.js';
  12. var RenderableObject = function () {
  13. this.id = 0;
  14. this.object = null;
  15. this.z = 0;
  16. this.renderOrder = 0;
  17. };
  18. //
  19. var RenderableFace = function () {
  20. this.id = 0;
  21. this.v1 = new RenderableVertex();
  22. this.v2 = new RenderableVertex();
  23. this.v3 = new RenderableVertex();
  24. this.normalModel = new Vector3();
  25. this.vertexNormalsModel = [ new Vector3(), new Vector3(), new Vector3() ];
  26. this.vertexNormalsLength = 0;
  27. this.color = new Color();
  28. this.material = null;
  29. this.uvs = [ new Vector2(), new Vector2(), new Vector2() ];
  30. this.z = 0;
  31. this.renderOrder = 0;
  32. };
  33. //
  34. var RenderableVertex = function () {
  35. this.position = new Vector3();
  36. this.positionWorld = new Vector3();
  37. this.positionScreen = new Vector4();
  38. this.visible = true;
  39. };
  40. RenderableVertex.prototype.copy = function ( vertex ) {
  41. this.positionWorld.copy( vertex.positionWorld );
  42. this.positionScreen.copy( vertex.positionScreen );
  43. };
  44. //
  45. var RenderableLine = function () {
  46. this.id = 0;
  47. this.v1 = new RenderableVertex();
  48. this.v2 = new RenderableVertex();
  49. this.vertexColors = [ new Color(), new Color() ];
  50. this.material = null;
  51. this.z = 0;
  52. this.renderOrder = 0;
  53. };
  54. //
  55. var RenderableSprite = function () {
  56. this.id = 0;
  57. this.object = null;
  58. this.x = 0;
  59. this.y = 0;
  60. this.z = 0;
  61. this.rotation = 0;
  62. this.scale = new Vector2();
  63. this.material = null;
  64. this.renderOrder = 0;
  65. };
  66. //
  67. var Projector = function () {
  68. var _object, _objectCount, _objectPool = [], _objectPoolLength = 0,
  69. _vertex, _vertexCount, _vertexPool = [], _vertexPoolLength = 0,
  70. _face, _faceCount, _facePool = [], _facePoolLength = 0,
  71. _line, _lineCount, _linePool = [], _linePoolLength = 0,
  72. _sprite, _spriteCount, _spritePool = [], _spritePoolLength = 0,
  73. _renderData = { objects: [], lights: [], elements: [] },
  74. _vector3 = new Vector3(),
  75. _vector4 = new Vector4(),
  76. _clipBox = new Box3( new Vector3( - 1, - 1, - 1 ), new Vector3( 1, 1, 1 ) ),
  77. _boundingBox = new Box3(),
  78. _points3 = new Array( 3 ),
  79. _viewMatrix = new Matrix4(),
  80. _viewProjectionMatrix = new Matrix4(),
  81. _modelMatrix,
  82. _modelViewProjectionMatrix = new Matrix4(),
  83. _frustum = new Frustum();
  84. //
  85. this.projectVector = function ( vector, camera ) {
  86. console.warn( 'THREE.Projector: .projectVector() is now vector.project().' );
  87. vector.project( camera );
  88. };
  89. this.unprojectVector = function ( vector, camera ) {
  90. console.warn( 'THREE.Projector: .unprojectVector() is now vector.unproject().' );
  91. vector.unproject( camera );
  92. };
  93. this.pickingRay = function () {
  94. console.error( 'THREE.Projector: .pickingRay() is now raycaster.setFromCamera().' );
  95. };
  96. //
  97. var RenderList = function () {
  98. var normals = [];
  99. var colors = [];
  100. var uvs = [];
  101. var object = null;
  102. var normalMatrix = new Matrix3();
  103. function setObject( value ) {
  104. object = value;
  105. normalMatrix.getNormalMatrix( object.matrixWorld );
  106. normals.length = 0;
  107. colors.length = 0;
  108. uvs.length = 0;
  109. }
  110. function projectVertex( vertex ) {
  111. var position = vertex.position;
  112. var positionWorld = vertex.positionWorld;
  113. var positionScreen = vertex.positionScreen;
  114. positionWorld.copy( position ).applyMatrix4( _modelMatrix );
  115. positionScreen.copy( positionWorld ).applyMatrix4( _viewProjectionMatrix );
  116. var invW = 1 / positionScreen.w;
  117. positionScreen.x *= invW;
  118. positionScreen.y *= invW;
  119. positionScreen.z *= invW;
  120. vertex.visible = positionScreen.x >= - 1 && positionScreen.x <= 1 &&
  121. positionScreen.y >= - 1 && positionScreen.y <= 1 &&
  122. positionScreen.z >= - 1 && positionScreen.z <= 1;
  123. }
  124. function pushVertex( x, y, z ) {
  125. _vertex = getNextVertexInPool();
  126. _vertex.position.set( x, y, z );
  127. projectVertex( _vertex );
  128. }
  129. function pushNormal( x, y, z ) {
  130. normals.push( x, y, z );
  131. }
  132. function pushColor( r, g, b ) {
  133. colors.push( r, g, b );
  134. }
  135. function pushUv( x, y ) {
  136. uvs.push( x, y );
  137. }
  138. function checkTriangleVisibility( v1, v2, v3 ) {
  139. if ( v1.visible === true || v2.visible === true || v3.visible === true ) return true;
  140. _points3[ 0 ] = v1.positionScreen;
  141. _points3[ 1 ] = v2.positionScreen;
  142. _points3[ 2 ] = v3.positionScreen;
  143. return _clipBox.intersectsBox( _boundingBox.setFromPoints( _points3 ) );
  144. }
  145. function checkBackfaceCulling( v1, v2, v3 ) {
  146. return ( ( v3.positionScreen.x - v1.positionScreen.x ) *
  147. ( v2.positionScreen.y - v1.positionScreen.y ) -
  148. ( v3.positionScreen.y - v1.positionScreen.y ) *
  149. ( v2.positionScreen.x - v1.positionScreen.x ) ) < 0;
  150. }
  151. function pushLine( a, b ) {
  152. var v1 = _vertexPool[ a ];
  153. var v2 = _vertexPool[ b ];
  154. // Clip
  155. v1.positionScreen.copy( v1.position ).applyMatrix4( _modelViewProjectionMatrix );
  156. v2.positionScreen.copy( v2.position ).applyMatrix4( _modelViewProjectionMatrix );
  157. if ( clipLine( v1.positionScreen, v2.positionScreen ) === true ) {
  158. // Perform the perspective divide
  159. v1.positionScreen.multiplyScalar( 1 / v1.positionScreen.w );
  160. v2.positionScreen.multiplyScalar( 1 / v2.positionScreen.w );
  161. _line = getNextLineInPool();
  162. _line.id = object.id;
  163. _line.v1.copy( v1 );
  164. _line.v2.copy( v2 );
  165. _line.z = Math.max( v1.positionScreen.z, v2.positionScreen.z );
  166. _line.renderOrder = object.renderOrder;
  167. _line.material = object.material;
  168. if ( object.material.vertexColors ) {
  169. _line.vertexColors[ 0 ].fromArray( colors, a * 3 );
  170. _line.vertexColors[ 1 ].fromArray( colors, b * 3 );
  171. }
  172. _renderData.elements.push( _line );
  173. }
  174. }
  175. function pushTriangle( a, b, c, material ) {
  176. var v1 = _vertexPool[ a ];
  177. var v2 = _vertexPool[ b ];
  178. var v3 = _vertexPool[ c ];
  179. if ( checkTriangleVisibility( v1, v2, v3 ) === false ) return;
  180. if ( material.side === DoubleSide || checkBackfaceCulling( v1, v2, v3 ) === true ) {
  181. _face = getNextFaceInPool();
  182. _face.id = object.id;
  183. _face.v1.copy( v1 );
  184. _face.v2.copy( v2 );
  185. _face.v3.copy( v3 );
  186. _face.z = ( v1.positionScreen.z + v2.positionScreen.z + v3.positionScreen.z ) / 3;
  187. _face.renderOrder = object.renderOrder;
  188. // face normal
  189. _vector3.subVectors( v3.position, v2.position );
  190. _vector4.subVectors( v1.position, v2.position );
  191. _vector3.cross( _vector4 );
  192. _face.normalModel.copy( _vector3 );
  193. _face.normalModel.applyMatrix3( normalMatrix ).normalize();
  194. for ( var i = 0; i < 3; i ++ ) {
  195. var normal = _face.vertexNormalsModel[ i ];
  196. normal.fromArray( normals, arguments[ i ] * 3 );
  197. normal.applyMatrix3( normalMatrix ).normalize();
  198. var uv = _face.uvs[ i ];
  199. uv.fromArray( uvs, arguments[ i ] * 2 );
  200. }
  201. _face.vertexNormalsLength = 3;
  202. _face.material = material;
  203. if ( material.vertexColors ) {
  204. _face.color.fromArray( colors, a * 3 );
  205. }
  206. _renderData.elements.push( _face );
  207. }
  208. }
  209. return {
  210. setObject: setObject,
  211. projectVertex: projectVertex,
  212. checkTriangleVisibility: checkTriangleVisibility,
  213. checkBackfaceCulling: checkBackfaceCulling,
  214. pushVertex: pushVertex,
  215. pushNormal: pushNormal,
  216. pushColor: pushColor,
  217. pushUv: pushUv,
  218. pushLine: pushLine,
  219. pushTriangle: pushTriangle
  220. };
  221. };
  222. var renderList = new RenderList();
  223. function projectObject( object ) {
  224. if ( object.visible === false ) return;
  225. if ( object.isLight ) {
  226. _renderData.lights.push( object );
  227. } else if ( object.isMesh || object.isLine || object.isPoints ) {
  228. if ( object.material.visible === false ) return;
  229. if ( object.frustumCulled === true && _frustum.intersectsObject( object ) === false ) return;
  230. addObject( object );
  231. } else if ( object.isSprite ) {
  232. if ( object.material.visible === false ) return;
  233. if ( object.frustumCulled === true && _frustum.intersectsSprite( object ) === false ) return;
  234. addObject( object );
  235. }
  236. var children = object.children;
  237. for ( var i = 0, l = children.length; i < l; i ++ ) {
  238. projectObject( children[ i ] );
  239. }
  240. }
  241. function addObject( object ) {
  242. _object = getNextObjectInPool();
  243. _object.id = object.id;
  244. _object.object = object;
  245. _vector3.setFromMatrixPosition( object.matrixWorld );
  246. _vector3.applyMatrix4( _viewProjectionMatrix );
  247. _object.z = _vector3.z;
  248. _object.renderOrder = object.renderOrder;
  249. _renderData.objects.push( _object );
  250. }
  251. this.projectScene = function ( scene, camera, sortObjects, sortElements ) {
  252. _faceCount = 0;
  253. _lineCount = 0;
  254. _spriteCount = 0;
  255. _renderData.elements.length = 0;
  256. if ( scene.autoUpdate === true ) scene.updateMatrixWorld();
  257. if ( camera.parent === null ) camera.updateMatrixWorld();
  258. _viewMatrix.copy( camera.matrixWorldInverse );
  259. _viewProjectionMatrix.multiplyMatrices( camera.projectionMatrix, _viewMatrix );
  260. _frustum.setFromProjectionMatrix( _viewProjectionMatrix );
  261. //
  262. _objectCount = 0;
  263. _renderData.objects.length = 0;
  264. _renderData.lights.length = 0;
  265. projectObject( scene );
  266. if ( sortObjects === true ) {
  267. _renderData.objects.sort( painterSort );
  268. }
  269. //
  270. var objects = _renderData.objects;
  271. for ( var o = 0, ol = objects.length; o < ol; o ++ ) {
  272. var object = objects[ o ].object;
  273. var geometry = object.geometry;
  274. renderList.setObject( object );
  275. _modelMatrix = object.matrixWorld;
  276. _vertexCount = 0;
  277. if ( object.isMesh ) {
  278. if ( geometry.isBufferGeometry ) {
  279. var material = object.material;
  280. var isMultiMaterial = Array.isArray( material );
  281. var attributes = geometry.attributes;
  282. var groups = geometry.groups;
  283. if ( attributes.position === undefined ) continue;
  284. var positions = attributes.position.array;
  285. for ( var i = 0, l = positions.length; i < l; i += 3 ) {
  286. var x = positions[ i ];
  287. var y = positions[ i + 1 ];
  288. var z = positions[ i + 2 ];
  289. if ( material.morphTargets === true ) {
  290. var morphTargets = geometry.morphAttributes.position;
  291. var morphTargetsRelative = geometry.morphTargetsRelative;
  292. var morphInfluences = object.morphTargetInfluences;
  293. for ( var t = 0, tl = morphTargets.length; t < tl; t ++ ) {
  294. var influence = morphInfluences[ t ];
  295. if ( influence === 0 ) continue;
  296. var 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. var normals = attributes.normal.array;
  312. for ( var 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. var colors = attributes.color.array;
  318. for ( var 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. var uvs = attributes.uv.array;
  324. for ( var 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. var indices = geometry.index.array;
  330. if ( groups.length > 0 ) {
  331. for ( var g = 0; g < groups.length; g ++ ) {
  332. var group = groups[ g ];
  333. material = isMultiMaterial === true
  334. ? object.material[ group.materialIndex ]
  335. : object.material;
  336. if ( material === undefined ) continue;
  337. for ( var 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 ( var 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 ( var g = 0; g < groups.length; g ++ ) {
  349. var group = groups[ g ];
  350. material = isMultiMaterial === true
  351. ? object.material[ group.materialIndex ]
  352. : object.material;
  353. if ( material === undefined ) continue;
  354. for ( var 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 ( var 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 ( geometry.isGeometry ) {
  365. console.error( 'THREE.Projector no longer supports Geometry. Use THREE.BufferGeometry instead.' );
  366. return;
  367. }
  368. } else if ( object.isLine ) {
  369. _modelViewProjectionMatrix.multiplyMatrices( _viewProjectionMatrix, _modelMatrix );
  370. if ( geometry.isBufferGeometry ) {
  371. var attributes = geometry.attributes;
  372. if ( attributes.position !== undefined ) {
  373. var positions = attributes.position.array;
  374. for ( var i = 0, l = positions.length; i < l; i += 3 ) {
  375. renderList.pushVertex( positions[ i ], positions[ i + 1 ], positions[ i + 2 ] );
  376. }
  377. if ( attributes.color !== undefined ) {
  378. var colors = attributes.color.array;
  379. for ( var i = 0, l = colors.length; i < l; i += 3 ) {
  380. renderList.pushColor( colors[ i ], colors[ i + 1 ], colors[ i + 2 ] );
  381. }
  382. }
  383. if ( geometry.index !== null ) {
  384. var indices = geometry.index.array;
  385. for ( var i = 0, l = indices.length; i < l; i += 2 ) {
  386. renderList.pushLine( indices[ i ], indices[ i + 1 ] );
  387. }
  388. } else {
  389. var step = object.isLineSegments ? 2 : 1;
  390. for ( var i = 0, l = ( positions.length / 3 ) - 1; i < l; i += step ) {
  391. renderList.pushLine( i, i + 1 );
  392. }
  393. }
  394. }
  395. } else if ( geometry.isGeometry ) {
  396. console.error( 'THREE.Projector no longer supports Geometry. Use THREE.BufferGeometry instead.' );
  397. return;
  398. }
  399. } else if ( object.isPoints ) {
  400. _modelViewProjectionMatrix.multiplyMatrices( _viewProjectionMatrix, _modelMatrix );
  401. if ( geometry.isGeometry ) {
  402. console.error( 'THREE.Projector no longer supports Geometry. Use THREE.BufferGeometry instead.' );
  403. return;
  404. } else if ( geometry.isBufferGeometry ) {
  405. var attributes = geometry.attributes;
  406. if ( attributes.position !== undefined ) {
  407. var positions = attributes.position.array;
  408. for ( var i = 0, l = positions.length; i < l; i += 3 ) {
  409. _vector4.set( positions[ i ], positions[ i + 1 ], positions[ i + 2 ], 1 );
  410. _vector4.applyMatrix4( _modelViewProjectionMatrix );
  411. pushPoint( _vector4, object, camera );
  412. }
  413. }
  414. }
  415. } else if ( object.isSprite ) {
  416. object.modelViewMatrix.multiplyMatrices( camera.matrixWorldInverse, object.matrixWorld );
  417. _vector4.set( _modelMatrix.elements[ 12 ], _modelMatrix.elements[ 13 ], _modelMatrix.elements[ 14 ], 1 );
  418. _vector4.applyMatrix4( _viewProjectionMatrix );
  419. pushPoint( _vector4, object, camera );
  420. }
  421. }
  422. if ( sortElements === true ) {
  423. _renderData.elements.sort( painterSort );
  424. }
  425. return _renderData;
  426. };
  427. function pushPoint( _vector4, object, camera ) {
  428. var invW = 1 / _vector4.w;
  429. _vector4.z *= invW;
  430. if ( _vector4.z >= - 1 && _vector4.z <= 1 ) {
  431. _sprite = getNextSpriteInPool();
  432. _sprite.id = object.id;
  433. _sprite.x = _vector4.x * invW;
  434. _sprite.y = _vector4.y * invW;
  435. _sprite.z = _vector4.z;
  436. _sprite.renderOrder = object.renderOrder;
  437. _sprite.object = object;
  438. _sprite.rotation = object.rotation;
  439. _sprite.scale.x = object.scale.x * Math.abs( _sprite.x - ( _vector4.x + camera.projectionMatrix.elements[ 0 ] ) / ( _vector4.w + camera.projectionMatrix.elements[ 12 ] ) );
  440. _sprite.scale.y = object.scale.y * Math.abs( _sprite.y - ( _vector4.y + camera.projectionMatrix.elements[ 5 ] ) / ( _vector4.w + camera.projectionMatrix.elements[ 13 ] ) );
  441. _sprite.material = object.material;
  442. _renderData.elements.push( _sprite );
  443. }
  444. }
  445. // Pools
  446. function getNextObjectInPool() {
  447. if ( _objectCount === _objectPoolLength ) {
  448. var object = new RenderableObject();
  449. _objectPool.push( object );
  450. _objectPoolLength ++;
  451. _objectCount ++;
  452. return object;
  453. }
  454. return _objectPool[ _objectCount ++ ];
  455. }
  456. function getNextVertexInPool() {
  457. if ( _vertexCount === _vertexPoolLength ) {
  458. var vertex = new RenderableVertex();
  459. _vertexPool.push( vertex );
  460. _vertexPoolLength ++;
  461. _vertexCount ++;
  462. return vertex;
  463. }
  464. return _vertexPool[ _vertexCount ++ ];
  465. }
  466. function getNextFaceInPool() {
  467. if ( _faceCount === _facePoolLength ) {
  468. var face = new RenderableFace();
  469. _facePool.push( face );
  470. _facePoolLength ++;
  471. _faceCount ++;
  472. return face;
  473. }
  474. return _facePool[ _faceCount ++ ];
  475. }
  476. function getNextLineInPool() {
  477. if ( _lineCount === _linePoolLength ) {
  478. var line = new RenderableLine();
  479. _linePool.push( line );
  480. _linePoolLength ++;
  481. _lineCount ++;
  482. return line;
  483. }
  484. return _linePool[ _lineCount ++ ];
  485. }
  486. function getNextSpriteInPool() {
  487. if ( _spriteCount === _spritePoolLength ) {
  488. var sprite = new RenderableSprite();
  489. _spritePool.push( sprite );
  490. _spritePoolLength ++;
  491. _spriteCount ++;
  492. return sprite;
  493. }
  494. return _spritePool[ _spriteCount ++ ];
  495. }
  496. //
  497. function painterSort( a, b ) {
  498. if ( a.renderOrder !== b.renderOrder ) {
  499. return a.renderOrder - b.renderOrder;
  500. } else if ( a.z !== b.z ) {
  501. return b.z - a.z;
  502. } else if ( a.id !== b.id ) {
  503. return a.id - b.id;
  504. } else {
  505. return 0;
  506. }
  507. }
  508. function clipLine( s1, s2 ) {
  509. var alpha1 = 0, alpha2 = 1,
  510. // Calculate the boundary coordinate of each vertex for the near and far clip planes,
  511. // Z = -1 and Z = +1, respectively.
  512. bc1near = s1.z + s1.w,
  513. bc2near = s2.z + s2.w,
  514. bc1far = - s1.z + s1.w,
  515. bc2far = - s2.z + s2.w;
  516. if ( bc1near >= 0 && bc2near >= 0 && bc1far >= 0 && bc2far >= 0 ) {
  517. // Both vertices lie entirely within all clip planes.
  518. return true;
  519. } else if ( ( bc1near < 0 && bc2near < 0 ) || ( bc1far < 0 && bc2far < 0 ) ) {
  520. // Both vertices lie entirely outside one of the clip planes.
  521. return false;
  522. } else {
  523. // The line segment spans at least one clip plane.
  524. if ( bc1near < 0 ) {
  525. // v1 lies outside the near plane, v2 inside
  526. alpha1 = Math.max( alpha1, bc1near / ( bc1near - bc2near ) );
  527. } else if ( bc2near < 0 ) {
  528. // v2 lies outside the near plane, v1 inside
  529. alpha2 = Math.min( alpha2, bc1near / ( bc1near - bc2near ) );
  530. }
  531. if ( bc1far < 0 ) {
  532. // v1 lies outside the far plane, v2 inside
  533. alpha1 = Math.max( alpha1, bc1far / ( bc1far - bc2far ) );
  534. } else if ( bc2far < 0 ) {
  535. // v2 lies outside the far plane, v2 inside
  536. alpha2 = Math.min( alpha2, bc1far / ( bc1far - bc2far ) );
  537. }
  538. if ( alpha2 < alpha1 ) {
  539. // The line segment spans two boundaries, but is outside both of them.
  540. // (This can't happen when we're only clipping against just near/far but good
  541. // to leave the check here for future usage if other clip planes are added.)
  542. return false;
  543. } else {
  544. // Update the s1 and s2 vertices to match the clipped line segment.
  545. s1.lerp( s2, alpha1 );
  546. s2.lerp( s1, 1 - alpha2 );
  547. return true;
  548. }
  549. }
  550. }
  551. };
  552. export { RenderableObject, RenderableFace, RenderableVertex, RenderableLine, RenderableSprite, Projector };