Projector.js 19 KB

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  1. THREE.RenderableObject = function () {
  2. this.id = 0;
  3. this.object = null;
  4. this.z = 0;
  5. this.renderOrder = 0;
  6. };
  7. //
  8. THREE.RenderableFace = function () {
  9. this.id = 0;
  10. this.v1 = new THREE.RenderableVertex();
  11. this.v2 = new THREE.RenderableVertex();
  12. this.v3 = new THREE.RenderableVertex();
  13. this.normalModel = new THREE.Vector3();
  14. this.vertexNormalsModel = [ new THREE.Vector3(), new THREE.Vector3(), new THREE.Vector3() ];
  15. this.vertexNormalsLength = 0;
  16. this.color = new THREE.Color();
  17. this.material = null;
  18. this.uvs = [ new THREE.Vector2(), new THREE.Vector2(), new THREE.Vector2() ];
  19. this.z = 0;
  20. this.renderOrder = 0;
  21. };
  22. //
  23. THREE.RenderableVertex = function () {
  24. this.position = new THREE.Vector3();
  25. this.positionWorld = new THREE.Vector3();
  26. this.positionScreen = new THREE.Vector4();
  27. this.visible = true;
  28. };
  29. THREE.RenderableVertex.prototype.copy = function ( vertex ) {
  30. this.positionWorld.copy( vertex.positionWorld );
  31. this.positionScreen.copy( vertex.positionScreen );
  32. };
  33. //
  34. THREE.RenderableLine = function () {
  35. this.id = 0;
  36. this.v1 = new THREE.RenderableVertex();
  37. this.v2 = new THREE.RenderableVertex();
  38. this.vertexColors = [ new THREE.Color(), new THREE.Color() ];
  39. this.material = null;
  40. this.z = 0;
  41. this.renderOrder = 0;
  42. };
  43. //
  44. THREE.RenderableSprite = function () {
  45. this.id = 0;
  46. this.object = null;
  47. this.x = 0;
  48. this.y = 0;
  49. this.z = 0;
  50. this.rotation = 0;
  51. this.scale = new THREE.Vector2();
  52. this.material = null;
  53. this.renderOrder = 0;
  54. };
  55. //
  56. THREE.Projector = function () {
  57. var _object, _objectCount, _objectPool = [], _objectPoolLength = 0,
  58. _vertex, _vertexCount, _vertexPool = [], _vertexPoolLength = 0,
  59. _face, _faceCount, _facePool = [], _facePoolLength = 0,
  60. _line, _lineCount, _linePool = [], _linePoolLength = 0,
  61. _sprite, _spriteCount, _spritePool = [], _spritePoolLength = 0,
  62. _renderData = { objects: [], lights: [], elements: [] },
  63. _vector3 = new THREE.Vector3(),
  64. _vector4 = new THREE.Vector4(),
  65. _clipBox = new THREE.Box3( new THREE.Vector3( - 1, - 1, - 1 ), new THREE.Vector3( 1, 1, 1 ) ),
  66. _boundingBox = new THREE.Box3(),
  67. _points3 = new Array( 3 ),
  68. _viewMatrix = new THREE.Matrix4(),
  69. _viewProjectionMatrix = new THREE.Matrix4(),
  70. _modelMatrix,
  71. _modelViewProjectionMatrix = new THREE.Matrix4(),
  72. _frustum = new THREE.Frustum();
  73. //
  74. this.projectVector = function ( vector, camera ) {
  75. console.warn( 'THREE.Projector: .projectVector() is now vector.project().' );
  76. vector.project( camera );
  77. };
  78. this.unprojectVector = function ( vector, camera ) {
  79. console.warn( 'THREE.Projector: .unprojectVector() is now vector.unproject().' );
  80. vector.unproject( camera );
  81. };
  82. this.pickingRay = function () {
  83. console.error( 'THREE.Projector: .pickingRay() is now raycaster.setFromCamera().' );
  84. };
  85. //
  86. var RenderList = function () {
  87. var normals = [];
  88. var colors = [];
  89. var uvs = [];
  90. var object = null;
  91. var normalMatrix = new THREE.Matrix3();
  92. function setObject( value ) {
  93. object = value;
  94. normalMatrix.getNormalMatrix( object.matrixWorld );
  95. normals.length = 0;
  96. colors.length = 0;
  97. uvs.length = 0;
  98. }
  99. function projectVertex( vertex ) {
  100. var position = vertex.position;
  101. var positionWorld = vertex.positionWorld;
  102. var positionScreen = vertex.positionScreen;
  103. positionWorld.copy( position ).applyMatrix4( _modelMatrix );
  104. positionScreen.copy( positionWorld ).applyMatrix4( _viewProjectionMatrix );
  105. var invW = 1 / positionScreen.w;
  106. positionScreen.x *= invW;
  107. positionScreen.y *= invW;
  108. positionScreen.z *= invW;
  109. vertex.visible = positionScreen.x >= - 1 && positionScreen.x <= 1 &&
  110. positionScreen.y >= - 1 && positionScreen.y <= 1 &&
  111. positionScreen.z >= - 1 && positionScreen.z <= 1;
  112. }
  113. function pushVertex( x, y, z ) {
  114. _vertex = getNextVertexInPool();
  115. _vertex.position.set( x, y, z );
  116. projectVertex( _vertex );
  117. }
  118. function pushNormal( x, y, z ) {
  119. normals.push( x, y, z );
  120. }
  121. function pushColor( r, g, b ) {
  122. colors.push( r, g, b );
  123. }
  124. function pushUv( x, y ) {
  125. uvs.push( x, y );
  126. }
  127. function checkTriangleVisibility( v1, v2, v3 ) {
  128. if ( v1.visible === true || v2.visible === true || v3.visible === true ) return true;
  129. _points3[ 0 ] = v1.positionScreen;
  130. _points3[ 1 ] = v2.positionScreen;
  131. _points3[ 2 ] = v3.positionScreen;
  132. return _clipBox.intersectsBox( _boundingBox.setFromPoints( _points3 ) );
  133. }
  134. function checkBackfaceCulling( v1, v2, v3 ) {
  135. return ( ( v3.positionScreen.x - v1.positionScreen.x ) *
  136. ( v2.positionScreen.y - v1.positionScreen.y ) -
  137. ( v3.positionScreen.y - v1.positionScreen.y ) *
  138. ( v2.positionScreen.x - v1.positionScreen.x ) ) < 0;
  139. }
  140. function pushLine( a, b ) {
  141. var v1 = _vertexPool[ a ];
  142. var v2 = _vertexPool[ b ];
  143. // Clip
  144. v1.positionScreen.copy( v1.position ).applyMatrix4( _modelViewProjectionMatrix );
  145. v2.positionScreen.copy( v2.position ).applyMatrix4( _modelViewProjectionMatrix );
  146. if ( clipLine( v1.positionScreen, v2.positionScreen ) === true ) {
  147. // Perform the perspective divide
  148. v1.positionScreen.multiplyScalar( 1 / v1.positionScreen.w );
  149. v2.positionScreen.multiplyScalar( 1 / v2.positionScreen.w );
  150. _line = getNextLineInPool();
  151. _line.id = object.id;
  152. _line.v1.copy( v1 );
  153. _line.v2.copy( v2 );
  154. _line.z = Math.max( v1.positionScreen.z, v2.positionScreen.z );
  155. _line.renderOrder = object.renderOrder;
  156. _line.material = object.material;
  157. if ( object.material.vertexColors ) {
  158. _line.vertexColors[ 0 ].fromArray( colors, a * 3 );
  159. _line.vertexColors[ 1 ].fromArray( colors, b * 3 );
  160. }
  161. _renderData.elements.push( _line );
  162. }
  163. }
  164. function pushTriangle( a, b, c, material ) {
  165. var v1 = _vertexPool[ a ];
  166. var v2 = _vertexPool[ b ];
  167. var v3 = _vertexPool[ c ];
  168. if ( checkTriangleVisibility( v1, v2, v3 ) === false ) return;
  169. if ( material.side === THREE.DoubleSide || checkBackfaceCulling( v1, v2, v3 ) === true ) {
  170. _face = getNextFaceInPool();
  171. _face.id = object.id;
  172. _face.v1.copy( v1 );
  173. _face.v2.copy( v2 );
  174. _face.v3.copy( v3 );
  175. _face.z = ( v1.positionScreen.z + v2.positionScreen.z + v3.positionScreen.z ) / 3;
  176. _face.renderOrder = object.renderOrder;
  177. // face normal
  178. _vector3.subVectors( v3.position, v2.position );
  179. _vector4.subVectors( v1.position, v2.position );
  180. _vector3.cross( _vector4 );
  181. _face.normalModel.copy( _vector3 );
  182. _face.normalModel.applyMatrix3( normalMatrix ).normalize();
  183. for ( var i = 0; i < 3; i ++ ) {
  184. var normal = _face.vertexNormalsModel[ i ];
  185. normal.fromArray( normals, arguments[ i ] * 3 );
  186. normal.applyMatrix3( normalMatrix ).normalize();
  187. var uv = _face.uvs[ i ];
  188. uv.fromArray( uvs, arguments[ i ] * 2 );
  189. }
  190. _face.vertexNormalsLength = 3;
  191. _face.material = material;
  192. if ( material.vertexColors ) {
  193. _face.color.fromArray( colors, a * 3 );
  194. }
  195. _renderData.elements.push( _face );
  196. }
  197. }
  198. return {
  199. setObject: setObject,
  200. projectVertex: projectVertex,
  201. checkTriangleVisibility: checkTriangleVisibility,
  202. checkBackfaceCulling: checkBackfaceCulling,
  203. pushVertex: pushVertex,
  204. pushNormal: pushNormal,
  205. pushColor: pushColor,
  206. pushUv: pushUv,
  207. pushLine: pushLine,
  208. pushTriangle: pushTriangle
  209. };
  210. };
  211. var renderList = new RenderList();
  212. function projectObject( object ) {
  213. if ( object.visible === false ) return;
  214. if ( object.isLight ) {
  215. _renderData.lights.push( object );
  216. } else if ( object.isMesh || object.isLine || object.isPoints ) {
  217. if ( object.material.visible === false ) return;
  218. if ( object.frustumCulled === true && _frustum.intersectsObject( object ) === false ) return;
  219. addObject( object );
  220. } else if ( object.isSprite ) {
  221. if ( object.material.visible === false ) return;
  222. if ( object.frustumCulled === true && _frustum.intersectsSprite( object ) === false ) return;
  223. addObject( object );
  224. }
  225. var children = object.children;
  226. for ( var i = 0, l = children.length; i < l; i ++ ) {
  227. projectObject( children[ i ] );
  228. }
  229. }
  230. function addObject( object ) {
  231. _object = getNextObjectInPool();
  232. _object.id = object.id;
  233. _object.object = object;
  234. _vector3.setFromMatrixPosition( object.matrixWorld );
  235. _vector3.applyMatrix4( _viewProjectionMatrix );
  236. _object.z = _vector3.z;
  237. _object.renderOrder = object.renderOrder;
  238. _renderData.objects.push( _object );
  239. }
  240. this.projectScene = function ( scene, camera, sortObjects, sortElements ) {
  241. _faceCount = 0;
  242. _lineCount = 0;
  243. _spriteCount = 0;
  244. _renderData.elements.length = 0;
  245. if ( scene.autoUpdate === true ) scene.updateMatrixWorld();
  246. if ( camera.parent === null ) camera.updateMatrixWorld();
  247. _viewMatrix.copy( camera.matrixWorldInverse );
  248. _viewProjectionMatrix.multiplyMatrices( camera.projectionMatrix, _viewMatrix );
  249. _frustum.setFromProjectionMatrix( _viewProjectionMatrix );
  250. //
  251. _objectCount = 0;
  252. _renderData.objects.length = 0;
  253. _renderData.lights.length = 0;
  254. projectObject( scene );
  255. if ( sortObjects === true ) {
  256. _renderData.objects.sort( painterSort );
  257. }
  258. //
  259. var objects = _renderData.objects;
  260. for ( var o = 0, ol = objects.length; o < ol; o ++ ) {
  261. var object = objects[ o ].object;
  262. var geometry = object.geometry;
  263. renderList.setObject( object );
  264. _modelMatrix = object.matrixWorld;
  265. _vertexCount = 0;
  266. if ( object.isMesh ) {
  267. if ( geometry.isBufferGeometry ) {
  268. var material = object.material;
  269. var isMultiMaterial = Array.isArray( material );
  270. var attributes = geometry.attributes;
  271. var groups = geometry.groups;
  272. if ( attributes.position === undefined ) continue;
  273. var positions = attributes.position.array;
  274. for ( var i = 0, l = positions.length; i < l; i += 3 ) {
  275. var x = positions[ i ];
  276. var y = positions[ i + 1 ];
  277. var z = positions[ i + 2 ];
  278. if ( material.morphTargets === true ) {
  279. var morphTargets = geometry.morphAttributes.position;
  280. var morphTargetsRelative = geometry.morphTargetsRelative;
  281. var morphInfluences = object.morphTargetInfluences;
  282. for ( var t = 0, tl = morphTargets.length; t < tl; t ++ ) {
  283. var influence = morphInfluences[ t ];
  284. if ( influence === 0 ) continue;
  285. var target = morphTargets[ t ];
  286. if ( morphTargetsRelative ) {
  287. x += target.getX( i / 3 ) * influence;
  288. y += target.getY( i / 3 ) * influence;
  289. z += target.getZ( i / 3 ) * influence;
  290. } else {
  291. x += ( target.getX( i / 3 ) - positions[ i ] ) * influence;
  292. y += ( target.getY( i / 3 ) - positions[ i + 1 ] ) * influence;
  293. z += ( target.getZ( i / 3 ) - positions[ i + 2 ] ) * influence;
  294. }
  295. }
  296. }
  297. renderList.pushVertex( x, y, z );
  298. }
  299. if ( attributes.normal !== undefined ) {
  300. var normals = attributes.normal.array;
  301. for ( var i = 0, l = normals.length; i < l; i += 3 ) {
  302. renderList.pushNormal( normals[ i ], normals[ i + 1 ], normals[ i + 2 ] );
  303. }
  304. }
  305. if ( attributes.color !== undefined ) {
  306. var colors = attributes.color.array;
  307. for ( var i = 0, l = colors.length; i < l; i += 3 ) {
  308. renderList.pushColor( colors[ i ], colors[ i + 1 ], colors[ i + 2 ] );
  309. }
  310. }
  311. if ( attributes.uv !== undefined ) {
  312. var uvs = attributes.uv.array;
  313. for ( var i = 0, l = uvs.length; i < l; i += 2 ) {
  314. renderList.pushUv( uvs[ i ], uvs[ i + 1 ] );
  315. }
  316. }
  317. if ( geometry.index !== null ) {
  318. var indices = geometry.index.array;
  319. if ( groups.length > 0 ) {
  320. for ( var g = 0; g < groups.length; g ++ ) {
  321. var group = groups[ g ];
  322. material = isMultiMaterial === true
  323. ? object.material[ group.materialIndex ]
  324. : object.material;
  325. if ( material === undefined ) continue;
  326. for ( var i = group.start, l = group.start + group.count; i < l; i += 3 ) {
  327. renderList.pushTriangle( indices[ i ], indices[ i + 1 ], indices[ i + 2 ], material );
  328. }
  329. }
  330. } else {
  331. for ( var i = 0, l = indices.length; i < l; i += 3 ) {
  332. renderList.pushTriangle( indices[ i ], indices[ i + 1 ], indices[ i + 2 ], material );
  333. }
  334. }
  335. } else {
  336. if ( groups.length > 0 ) {
  337. for ( var g = 0; g < groups.length; g ++ ) {
  338. var group = groups[ g ];
  339. material = isMultiMaterial === true
  340. ? object.material[ group.materialIndex ]
  341. : object.material;
  342. if ( material === undefined ) continue;
  343. for ( var i = group.start, l = group.start + group.count; i < l; i += 3 ) {
  344. renderList.pushTriangle( i, i + 1, i + 2, material );
  345. }
  346. }
  347. } else {
  348. for ( var i = 0, l = positions.length / 3; i < l; i += 3 ) {
  349. renderList.pushTriangle( i, i + 1, i + 2, material );
  350. }
  351. }
  352. }
  353. } else if ( geometry.isGeometry ) {
  354. console.error( 'THREE.Projector no longer supports THREE.Geometry. Use THREE.BufferGeometry instead.' );
  355. return;
  356. }
  357. } else if ( object.isLine ) {
  358. _modelViewProjectionMatrix.multiplyMatrices( _viewProjectionMatrix, _modelMatrix );
  359. if ( geometry.isBufferGeometry ) {
  360. var attributes = geometry.attributes;
  361. if ( attributes.position !== undefined ) {
  362. var positions = attributes.position.array;
  363. for ( var i = 0, l = positions.length; i < l; i += 3 ) {
  364. renderList.pushVertex( positions[ i ], positions[ i + 1 ], positions[ i + 2 ] );
  365. }
  366. if ( attributes.color !== undefined ) {
  367. var colors = attributes.color.array;
  368. for ( var i = 0, l = colors.length; i < l; i += 3 ) {
  369. renderList.pushColor( colors[ i ], colors[ i + 1 ], colors[ i + 2 ] );
  370. }
  371. }
  372. if ( geometry.index !== null ) {
  373. var indices = geometry.index.array;
  374. for ( var i = 0, l = indices.length; i < l; i += 2 ) {
  375. renderList.pushLine( indices[ i ], indices[ i + 1 ] );
  376. }
  377. } else {
  378. var step = object.isLineSegments ? 2 : 1;
  379. for ( var i = 0, l = ( positions.length / 3 ) - 1; i < l; i += step ) {
  380. renderList.pushLine( i, i + 1 );
  381. }
  382. }
  383. }
  384. } else if ( geometry.isGeometry ) {
  385. console.error( 'THREE.Projector no longer supports THREE.Geometry. Use THREE.BufferGeometry instead.' );
  386. return;
  387. }
  388. } else if ( object.isPoints ) {
  389. _modelViewProjectionMatrix.multiplyMatrices( _viewProjectionMatrix, _modelMatrix );
  390. if ( geometry.isGeometry ) {
  391. console.error( 'THREE.Projector no longer supports THREE.Geometry. Use THREE.BufferGeometry instead.' );
  392. return;
  393. } else if ( geometry.isBufferGeometry ) {
  394. var attributes = geometry.attributes;
  395. if ( attributes.position !== undefined ) {
  396. var positions = attributes.position.array;
  397. for ( var i = 0, l = positions.length; i < l; i += 3 ) {
  398. _vector4.set( positions[ i ], positions[ i + 1 ], positions[ i + 2 ], 1 );
  399. _vector4.applyMatrix4( _modelViewProjectionMatrix );
  400. pushPoint( _vector4, object, camera );
  401. }
  402. }
  403. }
  404. } else if ( object.isSprite ) {
  405. object.modelViewMatrix.multiplyMatrices( camera.matrixWorldInverse, object.matrixWorld );
  406. _vector4.set( _modelMatrix.elements[ 12 ], _modelMatrix.elements[ 13 ], _modelMatrix.elements[ 14 ], 1 );
  407. _vector4.applyMatrix4( _viewProjectionMatrix );
  408. pushPoint( _vector4, object, camera );
  409. }
  410. }
  411. if ( sortElements === true ) {
  412. _renderData.elements.sort( painterSort );
  413. }
  414. return _renderData;
  415. };
  416. function pushPoint( _vector4, object, camera ) {
  417. var invW = 1 / _vector4.w;
  418. _vector4.z *= invW;
  419. if ( _vector4.z >= - 1 && _vector4.z <= 1 ) {
  420. _sprite = getNextSpriteInPool();
  421. _sprite.id = object.id;
  422. _sprite.x = _vector4.x * invW;
  423. _sprite.y = _vector4.y * invW;
  424. _sprite.z = _vector4.z;
  425. _sprite.renderOrder = object.renderOrder;
  426. _sprite.object = object;
  427. _sprite.rotation = object.rotation;
  428. _sprite.scale.x = object.scale.x * Math.abs( _sprite.x - ( _vector4.x + camera.projectionMatrix.elements[ 0 ] ) / ( _vector4.w + camera.projectionMatrix.elements[ 12 ] ) );
  429. _sprite.scale.y = object.scale.y * Math.abs( _sprite.y - ( _vector4.y + camera.projectionMatrix.elements[ 5 ] ) / ( _vector4.w + camera.projectionMatrix.elements[ 13 ] ) );
  430. _sprite.material = object.material;
  431. _renderData.elements.push( _sprite );
  432. }
  433. }
  434. // Pools
  435. function getNextObjectInPool() {
  436. if ( _objectCount === _objectPoolLength ) {
  437. var object = new THREE.RenderableObject();
  438. _objectPool.push( object );
  439. _objectPoolLength ++;
  440. _objectCount ++;
  441. return object;
  442. }
  443. return _objectPool[ _objectCount ++ ];
  444. }
  445. function getNextVertexInPool() {
  446. if ( _vertexCount === _vertexPoolLength ) {
  447. var vertex = new THREE.RenderableVertex();
  448. _vertexPool.push( vertex );
  449. _vertexPoolLength ++;
  450. _vertexCount ++;
  451. return vertex;
  452. }
  453. return _vertexPool[ _vertexCount ++ ];
  454. }
  455. function getNextFaceInPool() {
  456. if ( _faceCount === _facePoolLength ) {
  457. var face = new THREE.RenderableFace();
  458. _facePool.push( face );
  459. _facePoolLength ++;
  460. _faceCount ++;
  461. return face;
  462. }
  463. return _facePool[ _faceCount ++ ];
  464. }
  465. function getNextLineInPool() {
  466. if ( _lineCount === _linePoolLength ) {
  467. var line = new THREE.RenderableLine();
  468. _linePool.push( line );
  469. _linePoolLength ++;
  470. _lineCount ++;
  471. return line;
  472. }
  473. return _linePool[ _lineCount ++ ];
  474. }
  475. function getNextSpriteInPool() {
  476. if ( _spriteCount === _spritePoolLength ) {
  477. var sprite = new THREE.RenderableSprite();
  478. _spritePool.push( sprite );
  479. _spritePoolLength ++;
  480. _spriteCount ++;
  481. return sprite;
  482. }
  483. return _spritePool[ _spriteCount ++ ];
  484. }
  485. //
  486. function painterSort( a, b ) {
  487. if ( a.renderOrder !== b.renderOrder ) {
  488. return a.renderOrder - b.renderOrder;
  489. } else if ( a.z !== b.z ) {
  490. return b.z - a.z;
  491. } else if ( a.id !== b.id ) {
  492. return a.id - b.id;
  493. } else {
  494. return 0;
  495. }
  496. }
  497. function clipLine( s1, s2 ) {
  498. var alpha1 = 0, alpha2 = 1,
  499. // Calculate the boundary coordinate of each vertex for the near and far clip planes,
  500. // Z = -1 and Z = +1, respectively.
  501. bc1near = s1.z + s1.w,
  502. bc2near = s2.z + s2.w,
  503. bc1far = - s1.z + s1.w,
  504. bc2far = - s2.z + s2.w;
  505. if ( bc1near >= 0 && bc2near >= 0 && bc1far >= 0 && bc2far >= 0 ) {
  506. // Both vertices lie entirely within all clip planes.
  507. return true;
  508. } else if ( ( bc1near < 0 && bc2near < 0 ) || ( bc1far < 0 && bc2far < 0 ) ) {
  509. // Both vertices lie entirely outside one of the clip planes.
  510. return false;
  511. } else {
  512. // The line segment spans at least one clip plane.
  513. if ( bc1near < 0 ) {
  514. // v1 lies outside the near plane, v2 inside
  515. alpha1 = Math.max( alpha1, bc1near / ( bc1near - bc2near ) );
  516. } else if ( bc2near < 0 ) {
  517. // v2 lies outside the near plane, v1 inside
  518. alpha2 = Math.min( alpha2, bc1near / ( bc1near - bc2near ) );
  519. }
  520. if ( bc1far < 0 ) {
  521. // v1 lies outside the far plane, v2 inside
  522. alpha1 = Math.max( alpha1, bc1far / ( bc1far - bc2far ) );
  523. } else if ( bc2far < 0 ) {
  524. // v2 lies outside the far plane, v2 inside
  525. alpha2 = Math.min( alpha2, bc1far / ( bc1far - bc2far ) );
  526. }
  527. if ( alpha2 < alpha1 ) {
  528. // The line segment spans two boundaries, but is outside both of them.
  529. // (This can't happen when we're only clipping against just near/far but good
  530. // to leave the check here for future usage if other clip planes are added.)
  531. return false;
  532. } else {
  533. // Update the s1 and s2 vertices to match the clipped line segment.
  534. s1.lerp( s2, alpha1 );
  535. s2.lerp( s1, 1 - alpha2 );
  536. return true;
  537. }
  538. }
  539. }
  540. };