content: import 'dart:math' as math;
  import 'dart:typed_data';
  import 'package:three_js/three_js.dart';
  
  /**
   * Tessellates the famous Utah teapot database by Martin Newell into triangles.
   *
   * Parameters: size = 50, segments = 10, bottom = true, lid = true, body = true,
   *   fitLid = false, blinn = true
   *
   * size is a relative scale: I've scaled the teapot to fit vertically between -1 and 1.
   * Think of it as a "radius".
   * segments - number of line segments to subdivide each patch edge;
   *   1 is possible but gives degenerates, so two is the real minimum.
   * bottom - boolean, if true (default) then the bottom patches are added. Some consider
   *   adding the bottom heresy, so set this to "false" to adhere to the One True Way.
   * lid - to remove the lid and look inside, set to true.
   * body - to remove the body and leave the lid, set this and "bottom" to false.
   * fitLid - the lid is a tad small in the original. This stretches it a bit so you can't
   *   see the teapot's insides through the gap.
   * blinn - Jim Blinn scaled the original data vertically by dividing by about 1.3 to look
   *   nicer. If you want to see the original teapot, similar to the real-world model, set
   *   this to false. True by default.
   *   See http://en.wikipedia.org/wiki/File:Original_Utah_Teapot.jpg for the original
   *   real-world teapot (from http://en.wikipedia.org/wiki/Utah_teapot).
   *
   * Note that the bottom (the last four patches) is not flat - blame Frank Crow, not me.
   *
   * The teapot should normally be rendered as a double sided object, since for some
   * patches both sides can be seen, e.g., the gap around the lid and inside the spout.
   *
   * Segments 'n' determines the number of triangles output.
   *   Total triangles = 32*2*n*n - 8*n    [degenerates at the top and bottom cusps are deleted]
   *
   *   size_factor   # triangles
   *       1          56
   *       2         240
   *       3         552
   *       4         992
   *
   *      10        6320
   *      20       25440
   *      30       57360
   *
   * Code converted from my ancient SPD software, http://tog.acm.org/resources/SPD/
   * Created for the Udacity course "Interactive Rendering", http://bit.ly/ericity
   * YouTube video on teapot history: https://www.youtube.com/watch?v=DxMfblPzFNc
   *
   * See https://en.wikipedia.org/wiki/Utah_teapot for the history of the teapot
   *
   */
  
  class TeapotGeometry extends BufferGeometry {
  
  	TeapotGeometry({
      double size = 50, 
      int segments = 10, 
      bool bottom = true, 
      bool lid = true, 
      bool body = true, 
      bool fitLid = true, 
      bool blinn = true 
    }):super(){
  
  		// 32 * 4 * 4 Bezier spline patches
  		const List<int> teapotPatches = [
  			/*rim*/
  			0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
  			3, 16, 17, 18, 7, 19, 20, 21, 11, 22, 23, 24, 15, 25, 26, 27,
  			18, 28, 29, 30, 21, 31, 32, 33, 24, 34, 35, 36, 27, 37, 38, 39,
  			30, 40, 41, 0, 33, 42, 43, 4, 36, 44, 45, 8, 39, 46, 47, 12,
  			/*body*/
  			12, 13, 14, 15, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59,
  			15, 25, 26, 27, 51, 60, 61, 62, 55, 63, 64, 65, 59, 66, 67, 68,
  			27, 37, 38, 39, 62, 69, 70, 71, 65, 72, 73, 74, 68, 75, 76, 77,
  			39, 46, 47, 12, 71, 78, 79, 48, 74, 80, 81, 52, 77, 82, 83, 56,
  			56, 57, 58, 59, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95,
  			59, 66, 67, 68, 87, 96, 97, 98, 91, 99, 100, 101, 95, 102, 103, 104,
  			68, 75, 76, 77, 98, 105, 106, 107, 101, 108, 109, 110, 104, 111, 112, 113,
  			77, 82, 83, 56, 107, 114, 115, 84, 110, 116, 117, 88, 113, 118, 119, 92,
  			/*handle*/
  			120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135,
  			123, 136, 137, 120, 127, 138, 139, 124, 131, 140, 141, 128, 135, 142, 143, 132,
  			132, 133, 134, 135, 144, 145, 146, 147, 148, 149, 150, 151, 68, 152, 153, 154,
  			135, 142, 143, 132, 147, 155, 156, 144, 151, 157, 158, 148, 154, 159, 160, 68,
  			/*spout*/
  			161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176,
  			164, 177, 178, 161, 168, 179, 180, 165, 172, 181, 182, 169, 176, 183, 184, 173,
  			173, 174, 175, 176, 185, 186, 187, 188, 189, 190, 191, 192, 193, 194, 195, 196,
  			176, 183, 184, 173, 188, 197, 198, 185, 192, 199, 200, 189, 196, 201, 202, 193,
  			/*lid*/
  			203, 203, 203, 203, 204, 205, 206, 207, 208, 208, 208, 208, 209, 210, 211, 212,
  			203, 203, 203, 203, 207, 213, 214, 215, 208, 208, 208, 208, 212, 216, 217, 218,
  			203, 203, 203, 203, 215, 219, 220, 221, 208, 208, 208, 208, 218, 222, 223, 224,
  			203, 203, 203, 203, 221, 225, 226, 204, 208, 208, 208, 208, 224, 227, 228, 209,
  			209, 210, 211, 212, 229, 230, 231, 232, 233, 234, 235, 236, 237, 238, 239, 240,
  			212, 216, 217, 218, 232, 241, 242, 243, 236, 244, 245, 246, 240, 247, 248, 249,
  			218, 222, 223, 224, 243, 250, 251, 252, 246, 253, 254, 255, 249, 256, 257, 258,
  			224, 227, 228, 209, 252, 259, 260, 229, 255, 261, 262, 233, 258, 263, 264, 237,
  			/*bottom*/
  			265, 265, 265, 265, 266, 267, 268, 269, 270, 271, 272, 273, 92, 119, 118, 113,
  			265, 265, 265, 265, 269, 274, 275, 276, 273, 277, 278, 279, 113, 112, 111, 104,
  			265, 265, 265, 265, 276, 280, 281, 282, 279, 283, 284, 285, 104, 103, 102, 95,
  			265, 265, 265, 265, 282, 286, 287, 266, 285, 288, 289, 270, 95, 94, 93, 92
  		];
  
  		const List<double> teapotVertices = [
  			1.4, 0, 2.4,
  			1.4, - 0.784, 2.4,
  			0.784, - 1.4, 2.4,
  			0, - 1.4, 2.4,
  			1.3375, 0, 2.53125,
  			1.3375, - 0.749, 2.53125,
  			0.749, - 1.3375, 2.53125,
  			0, - 1.3375, 2.53125,
  			1.4375, 0, 2.53125,
  			1.4375, - 0.805, 2.53125,
  			0.805, - 1.4375, 2.53125,
  			0, - 1.4375, 2.53125,
  			1.5, 0, 2.4,
  			1.5, - 0.84, 2.4,
  			0.84, - 1.5, 2.4,
  			0, - 1.5, 2.4,
  			- 0.784, - 1.4, 2.4,
  			- 1.4, - 0.784, 2.4,
  			- 1.4, 0, 2.4,
  			- 0.749, - 1.3375, 2.53125,
  			- 1.3375, - 0.749, 2.53125,
  			- 1.3375, 0, 2.53125,
  			- 0.805, - 1.4375, 2.53125,
  			- 1.4375, - 0.805, 2.53125,
  			- 1.4375, 0, 2.53125,
  			- 0.84, - 1.5, 2.4,
  			- 1.5, - 0.84, 2.4,
  			- 1.5, 0, 2.4,
  			- 1.4, 0.784, 2.4,
  			- 0.784, 1.4, 2.4,
  			0, 1.4, 2.4,
  			- 1.3375, 0.749, 2.53125,
  			- 0.749, 1.3375, 2.53125,
  			0, 1.3375, 2.53125,
  			- 1.4375, 0.805, 2.53125,
  			- 0.805, 1.4375, 2.53125,
  			0, 1.4375, 2.53125,
  			- 1.5, 0.84, 2.4,
  			- 0.84, 1.5, 2.4,
  			0, 1.5, 2.4,
  			0.784, 1.4, 2.4,
  			1.4, 0.784, 2.4,
  			0.749, 1.3375, 2.53125,
  			1.3375, 0.749, 2.53125,
  			0.805, 1.4375, 2.53125,
  			1.4375, 0.805, 2.53125,
  			0.84, 1.5, 2.4,
  			1.5, 0.84, 2.4,
  			1.75, 0, 1.875,
  			1.75, - 0.98, 1.875,
  			0.98, - 1.75, 1.875,
  			0, - 1.75, 1.875,
  			2, 0, 1.35,
  			2, - 1.12, 1.35,
  			1.12, - 2, 1.35,
  			0, - 2, 1.35,
  			2, 0, 0.9,
  			2, - 1.12, 0.9,
  			1.12, - 2, 0.9,
  			0, - 2, 0.9,
  			- 0.98, - 1.75, 1.875,
  			- 1.75, - 0.98, 1.875,
  			- 1.75, 0, 1.875,
  			- 1.12, - 2, 1.35,
  			- 2, - 1.12, 1.35,
  			- 2, 0, 1.35,
  			- 1.12, - 2, 0.9,
  			- 2, - 1.12, 0.9,
  			- 2, 0, 0.9,
  			- 1.75, 0.98, 1.875,
  			- 0.98, 1.75, 1.875,
  			0, 1.75, 1.875,
  			- 2, 1.12, 1.35,
  			- 1.12, 2, 1.35,
  			0, 2, 1.35,
  			- 2, 1.12, 0.9,
  			- 1.12, 2, 0.9,
  			0, 2, 0.9,
  			0.98, 1.75, 1.875,
  			1.75, 0.98, 1.875,
  			1.12, 2, 1.35,
  			2, 1.12, 1.35,
  			1.12, 2, 0.9,
  			2, 1.12, 0.9,
  			2, 0, 0.45,
  			2, - 1.12, 0.45,
  			1.12, - 2, 0.45,
  			0, - 2, 0.45,
  			1.5, 0, 0.225,
  			1.5, - 0.84, 0.225,
  			0.84, - 1.5, 0.225,
  			0, - 1.5, 0.225,
  			1.5, 0, 0.15,
  			1.5, - 0.84, 0.15,
  			0.84, - 1.5, 0.15,
  			0, - 1.5, 0.15,
  			- 1.12, - 2, 0.45,
  			- 2, - 1.12, 0.45,
  			- 2, 0, 0.45,
  			- 0.84, - 1.5, 0.225,
  			- 1.5, - 0.84, 0.225,
  			- 1.5, 0, 0.225,
  			- 0.84, - 1.5, 0.15,
  			- 1.5, - 0.84, 0.15,
  			- 1.5, 0, 0.15,
  			- 2, 1.12, 0.45,
  			- 1.12, 2, 0.45,
  			0, 2, 0.45,
  			- 1.5, 0.84, 0.225,
  			- 0.84, 1.5, 0.225,
  			0, 1.5, 0.225,
  			- 1.5, 0.84, 0.15,
  			- 0.84, 1.5, 0.15,
  			0, 1.5, 0.15,
  			1.12, 2, 0.45,
  			2, 1.12, 0.45,
  			0.84, 1.5, 0.225,
  			1.5, 0.84, 0.225,
  			0.84, 1.5, 0.15,
  			1.5, 0.84, 0.15,
  			- 1.6, 0, 2.025,
  			- 1.6, - 0.3, 2.025,
  			- 1.5, - 0.3, 2.25,
  			- 1.5, 0, 2.25,
  			- 2.3, 0, 2.025,
  			- 2.3, - 0.3, 2.025,
  			- 2.5, - 0.3, 2.25,
  			- 2.5, 0, 2.25,
  			- 2.7, 0, 2.025,
  			- 2.7, - 0.3, 2.025,
  			- 3, - 0.3, 2.25,
  			- 3, 0, 2.25,
  			- 2.7, 0, 1.8,
  			- 2.7, - 0.3, 1.8,
  			- 3, - 0.3, 1.8,
  			- 3, 0, 1.8,
  			- 1.5, 0.3, 2.25,
  			- 1.6, 0.3, 2.025,
  			- 2.5, 0.3, 2.25,
  			- 2.3, 0.3, 2.025,
  			- 3, 0.3, 2.25,
  			- 2.7, 0.3, 2.025,
  			- 3, 0.3, 1.8,
  			- 2.7, 0.3, 1.8,
  			- 2.7, 0, 1.575,
  			- 2.7, - 0.3, 1.575,
  			- 3, - 0.3, 1.35,
  			- 3, 0, 1.35,
  			- 2.5, 0, 1.125,
  			- 2.5, - 0.3, 1.125,
  			- 2.65, - 0.3, 0.9375,
  			- 2.65, 0, 0.9375,
  			- 2, - 0.3, 0.9,
  			- 1.9, - 0.3, 0.6,
  			- 1.9, 0, 0.6,
  			- 3, 0.3, 1.35,
  			- 2.7, 0.3, 1.575,
  			- 2.65, 0.3, 0.9375,
  			- 2.5, 0.3, 1.125,
  			- 1.9, 0.3, 0.6,
  			- 2, 0.3, 0.9,
  			1.7, 0, 1.425,
  			1.7, - 0.66, 1.425,
  			1.7, - 0.66, 0.6,
  			1.7, 0, 0.6,
  			2.6, 0, 1.425,
  			2.6, - 0.66, 1.425,
  			3.1, - 0.66, 0.825,
  			3.1, 0, 0.825,
  			2.3, 0, 2.1,
  			2.3, - 0.25, 2.1,
  			2.4, - 0.25, 2.025,
  			2.4, 0, 2.025,
  			2.7, 0, 2.4,
  			2.7, - 0.25, 2.4,
  			3.3, - 0.25, 2.4,
  			3.3, 0, 2.4,
  			1.7, 0.66, 0.6,
  			1.7, 0.66, 1.425,
  			3.1, 0.66, 0.825,
  			2.6, 0.66, 1.425,
  			2.4, 0.25, 2.025,
  			2.3, 0.25, 2.1,
  			3.3, 0.25, 2.4,
  			2.7, 0.25, 2.4,
  			2.8, 0, 2.475,
  			2.8, - 0.25, 2.475,
  			3.525, - 0.25, 2.49375,
  			3.525, 0, 2.49375,
  			2.9, 0, 2.475,
  			2.9, - 0.15, 2.475,
  			3.45, - 0.15, 2.5125,
  			3.45, 0, 2.5125,
  			2.8, 0, 2.4,
  			2.8, - 0.15, 2.4,
  			3.2, - 0.15, 2.4,
  			3.2, 0, 2.4,
  			3.525, 0.25, 2.49375,
  			2.8, 0.25, 2.475,
  			3.45, 0.15, 2.5125,
  			2.9, 0.15, 2.475,
  			3.2, 0.15, 2.4,
  			2.8, 0.15, 2.4,
  			0, 0, 3.15,
  			0.8, 0, 3.15,
  			0.8, - 0.45, 3.15,
  			0.45, - 0.8, 3.15,
  			0, - 0.8, 3.15,
  			0, 0, 2.85,
  			0.2, 0, 2.7,
  			0.2, - 0.112, 2.7,
  			0.112, - 0.2, 2.7,
  			0, - 0.2, 2.7,
  			- 0.45, - 0.8, 3.15,
  			- 0.8, - 0.45, 3.15,
  			- 0.8, 0, 3.15,
  			- 0.112, - 0.2, 2.7,
  			- 0.2, - 0.112, 2.7,
  			- 0.2, 0, 2.7,
  			- 0.8, 0.45, 3.15,
  			- 0.45, 0.8, 3.15,
  			0, 0.8, 3.15,
  			- 0.2, 0.112, 2.7,
  			- 0.112, 0.2, 2.7,
  			0, 0.2, 2.7,
  			0.45, 0.8, 3.15,
  			0.8, 0.45, 3.15,
  			0.112, 0.2, 2.7,
  			0.2, 0.112, 2.7,
  			0.4, 0, 2.55,
  			0.4, - 0.224, 2.55,
  			0.224, - 0.4, 2.55,
  			0, - 0.4, 2.55,
  			1.3, 0, 2.55,
  			1.3, - 0.728, 2.55,
  			0.728, - 1.3, 2.55,
  			0, - 1.3, 2.55,
  			1.3, 0, 2.4,
  			1.3, - 0.728, 2.4,
  			0.728, - 1.3, 2.4,
  			0, - 1.3, 2.4,
  			- 0.224, - 0.4, 2.55,
  			- 0.4, - 0.224, 2.55,
  			- 0.4, 0, 2.55,
  			- 0.728, - 1.3, 2.55,
  			- 1.3, - 0.728, 2.55,
  			- 1.3, 0, 2.55,
  			- 0.728, - 1.3, 2.4,
  			- 1.3, - 0.728, 2.4,
  			- 1.3, 0, 2.4,
  			- 0.4, 0.224, 2.55,
  			- 0.224, 0.4, 2.55,
  			0, 0.4, 2.55,
  			- 1.3, 0.728, 2.55,
  			- 0.728, 1.3, 2.55,
  			0, 1.3, 2.55,
  			- 1.3, 0.728, 2.4,
  			- 0.728, 1.3, 2.4,
  			0, 1.3, 2.4,
  			0.224, 0.4, 2.55,
  			0.4, 0.224, 2.55,
  			0.728, 1.3, 2.55,
  			1.3, 0.728, 2.55,
  			0.728, 1.3, 2.4,
  			1.3, 0.728, 2.4,
  			0, 0, 0,
  			1.425, 0, 0,
  			1.425, 0.798, 0,
  			0.798, 1.425, 0,
  			0, 1.425, 0,
  			1.5, 0, 0.075,
  			1.5, 0.84, 0.075,
  			0.84, 1.5, 0.075,
  			0, 1.5, 0.075,
  			- 0.798, 1.425, 0,
  			- 1.425, 0.798, 0,
  			- 1.425, 0, 0,
  			- 0.84, 1.5, 0.075,
  			- 1.5, 0.84, 0.075,
  			- 1.5, 0, 0.075,
  			- 1.425, - 0.798, 0,
  			- 0.798, - 1.425, 0,
  			0, - 1.425, 0,
  			- 1.5, - 0.84, 0.075,
  			- 0.84, - 1.5, 0.075,
  			0, - 1.5, 0.075,
  			0.798, - 1.425, 0,
  			1.425, - 0.798, 0,
  			0.84, - 1.5, 0.075,
  			1.5, - 0.84, 0.075
  		];
  
  		// number of segments per patch
  		segments = math.max( 2, segments.floor());
  
  		// Jim Blinn scaled the teapot down in size by about 1.3 for
  		// some rendering tests. He liked the proportions that he kept
  		// the data in this form. The model was distributed with these new
  		// proportions and became the norm. Trivia: comparing images of the
  		// real teapot and the computer model, the ratio for the bowl of the
  		// real teapot is more like 1.25, but since 1.3 is the traditional
  		// value given, we use it here.
  		const blinnScale = 1.3;
  
  		// scale the size to be the real scaling factor
  		final maxHeight = 3.15 * ( blinn ? 1 : blinnScale );
  
  		final maxHeight2 = maxHeight / 2;
  		final trueSize = size / maxHeight2;
  
  		// Number of elements depends on what is needed. Subtract degenerate
  		// triangles at tip of bottom and lid out in advance.
  		int numTriangles = bottom ? ( 8 * segments - 4 ) * segments : 0;
  		numTriangles += lid ? ( 16 * segments - 4 ) * segments : 0;
  		numTriangles += body ? 40 * segments * segments : 0;
  
  		final indices = Uint32List( numTriangles * 3 );
  
  		int numVertices = bottom ? 4 : 0;
  		numVertices += lid ? 8 : 0;
  		numVertices += body ? 20 : 0;
  		numVertices *= ( segments + 1 ) * ( segments + 1 );
  
  		final vertices = Float32List( numVertices * 3 );
  		final normals = Float32List( numVertices * 3 );
  		final uvs = Float32List( numVertices * 2 );
  
  		// Bezier form
  		final ms = Matrix4();
  		ms.setValues(
  			- 1.0, 3.0, - 3.0, 1.0,
  			3.0, - 6.0, 3.0, 0.0,
  			- 3.0, 3.0, 0.0, 0.0,
  			1.0, 0.0, 0.0, 0.0 );
  
  		final g = [];
  
  		final List<double> sp = [];
  		final List<double> tp = [];
  		final List<double> dsp = [];
  		final List<double> dtp = [];
  
  		// M * G * M matrix, sort of see
  		// http://www.cs.helsinki.fi/group/goa/mallinnus/curves/surfaces.html
  		final List<Matrix4> mgm = [];
  
  		final List<double> vert = [];
  		final List<double> sdir = [];
  		final List<double> tdir = [];
  
  		final norm = Vector3();
  
  		Vector4 tcoord;
  
  		double sval = 1.0;
  	  double tval = 1.0;
  		double dsval = 0;
  		double dtval = 0;
      int p = 0;
  
  		final normOut = Vector3();
  
  		final gmx = Matrix4();
  		final tmtx = Matrix4();
  
  		final vsp = Vector4();
  		final vtp = Vector4();
  		final vdsp = Vector4();
  		final vdtp = Vector4();
  
  		final vsdir = Vector3();
  		final vtdir = Vector3();
  
  		final mst = ms.clone();
  		mst.transpose();
  
  		// internal function: test if triangle has any matching vertices;
  		// if so, don't save triangle, since it won't display anything.
  		bool notDegenerate( vtx1, vtx2, vtx3 ) => // if any vertex matches, return false
  			! ( ( ( vertices[ vtx1 * 3 ] == vertices[ vtx2 * 3 ] ) &&
  					( vertices[ vtx1 * 3 + 1 ] == vertices[ vtx2 * 3 + 1 ] ) &&
  					( vertices[ vtx1 * 3 + 2 ] == vertices[ vtx2 * 3 + 2 ] ) ) ||
  					( ( vertices[ vtx1 * 3 ] == vertices[ vtx3 * 3 ] ) &&
  					( vertices[ vtx1 * 3 + 1 ] == vertices[ vtx3 * 3 + 1 ] ) &&
  					( vertices[ vtx1 * 3 + 2 ] == vertices[ vtx3 * 3 + 2 ] ) ) || ( vertices[ vtx2 * 3 ] == vertices[ vtx3 * 3 ] ) &&
  					( vertices[ vtx2 * 3 + 1 ] == vertices[ vtx3 * 3 + 1 ] ) &&
  					( vertices[ vtx2 * 3 + 2 ] == vertices[ vtx3 * 3 + 2 ] ) );
  
  
  		for (int i = 0; i < 3; i ++ ) {
  			mgm[ i ] = Matrix4();
  		}
  
  		final minPatches = body ? 0 : 20;
  		final maxPatches = bottom ? 32 : 28;
  
  		final vertPerRow = segments + 1;
  
  		int surfCount = 0;
  
  		int vertCount = 0;
  		int normCount = 0;
  		int uvCount = 0;
  
  		int indexCount = 0;
  
  		for ( int surf = minPatches; surf < maxPatches; surf ++ ) {
  			// lid is in the middle of the data, patches 20-27,
  			// so ignore it for this part of the loop if the lid is not desired
  			if ( lid || ( surf < 20 || surf >= 28 ) ) {
  				// get M * G * M matrix for x,y,z
  				for ( int i = 0; i < 3; i ++ ) {
  					// get control patches
  					for ( int r = 0; r < 4; r ++ ) {
  						for ( int c = 0; c < 4; c ++ ) {
  							// transposed
  							g[ c * 4 + r ] = teapotVertices[ teapotPatches[ surf * 16 + r * 4 + c ] * 3 + i ];
  
  							// is the lid to be made larger, and is this a point on the lid
  							// that is X or Y?
  							if ( fitLid && ( surf >= 20 && surf < 28 ) && ( i != 2 ) ) {
  								// increase XY size by 7.7%, found empirically. I don't
  								// increase Z so that the teapot will continue to fit in the
  								// space -1 to 1 for Y (Y is up for the final model).
  								g[ c * 4 + r ] *= 1.077;
  							}
  
  							// Blinn "fixed" the teapot by dividing Z by blinnScale, and that's the
  							// data we now use. The original teapot is taller. Fix it:
  							if ( ! blinn && ( i == 2 ) ) {
  								g[ c * 4 + r ] *= blinnScale;
  							}
  						}
  					}
  
  					gmx.setValues( g[ 0 ], g[ 1 ], g[ 2 ], g[ 3 ], g[ 4 ], g[ 5 ], g[ 6 ], g[ 7 ], g[ 8 ], g[ 9 ], g[ 10 ], g[ 11 ], g[ 12 ], g[ 13 ], g[ 14 ], g[ 15 ] );
  
  					tmtx.multiply2( gmx, ms );
  					mgm[ i ].multiply2( mst, tmtx );
  				}
  
  				// step along, get points, and output
  				for (int sstep = 0; sstep <= segments; sstep ++ ) {
  					final s = sstep / segments;
  
  					for (int tstep = 0; tstep <= segments; tstep ++ ) {
  						final t = tstep / segments;
  
  						// point from basis
  						// get power vectors and their derivatives
  						for (p = 4; p > 0 ;p --) {
  							sp[ p ] = sval;
  							tp[ p ] = tval;
  							sval *= s;
  							tval *= t;
  
  							if ( p == 3 ) {
  								dsp[ p ] = dtp[ p ] = 0.0;
  								dsval = dtval = 1.0;
  							} else {
  								dsp[ p ] = dsval * ( 3 - p );
  								dtp[ p ] = dtval * ( 3 - p );
  								dsval *= s;
  								dtval *= t;
  							}
  						}
  
  						vsp.copyFromArray( sp );
  						vtp.copyFromArray( tp );
  						vdsp.copyFromArray( dsp );
  						vdtp.copyFromArray( dtp );
  
  						// do for x,y,z
  						for (int i = 0; i < 3; i ++ ) {
  							// multiply power vectors times matrix to get value
  							tcoord = vsp.clone();
  							tcoord.applyMatrix4( mgm[ i ] );
  							vert[ i ] = tcoord.dot( vtp );
  
  							// get s and t tangent vectors
  							tcoord = vdsp.clone();
  							tcoord.applyMatrix4( mgm[ i ] );
  							sdir[ i ] = tcoord.dot( vtp );
  
  							tcoord = vsp.clone();
  							tcoord.applyMatrix4( mgm[ i ] );
  							tdir[ i ] = tcoord.dot( vdtp );
  						}
  
  						// find normal
  						vsdir.copyFromArray( sdir );
  						vtdir.copyFromArray( tdir );
  						norm.cross2( vtdir, vsdir );
  						norm.normalize();
  
  						// if X and Z length is 0, at the cusp, so point the normal up or down, depending on patch number
  						if ( vert[ 0 ] == 0 && vert[ 1 ] == 0 ) {
  							// if above the middle of the teapot, normal points up, else down
  							normOut.setValues( 0, vert[ 2 ] > maxHeight2 ? 1 : - 1, 0 );
  						} else {
  							// standard output: rotate on X axis
  							normOut.setValues( norm.x, norm.z, - norm.y );
  						}
  
  						// store it all
  						vertices[ vertCount ++ ] = trueSize * vert[ 0 ];
  						vertices[ vertCount ++ ] = trueSize * ( vert[ 2 ] - maxHeight2 );
  						vertices[ vertCount ++ ] = - trueSize * vert[ 1 ];
  
  						normals[ normCount ++ ] = normOut.x;
  						normals[ normCount ++ ] = normOut.y;
  						normals[ normCount ++ ] = normOut.z;
  
  						uvs[ uvCount ++ ] = 1 - t;
  						uvs[ uvCount ++ ] = 1 - s;
  					}
  				}
  
  				// save the faces
  				for (int sstep = 0; sstep < segments; sstep ++ ) {
  					for (int tstep = 0; tstep < segments; tstep ++ ) {
  						final v1 = surfCount * vertPerRow * vertPerRow + sstep * vertPerRow + tstep;
  						final v2 = v1 + 1;
  						final v3 = v2 + vertPerRow;
  						final v4 = v1 + vertPerRow;
  
  						// Normals and UVs cannot be shared. Without clone(), you can see the consequences
  						// of sharing if you call geometry.applyMatrix4( matrix ).
  						if ( notDegenerate( v1, v2, v3 ) ) {
  							indices[ indexCount ++ ] = v1;
  							indices[ indexCount ++ ] = v2;
  							indices[ indexCount ++ ] = v3;
  						}
  
  						if ( notDegenerate( v1, v3, v4 ) ) {
  							indices[ indexCount ++ ] = v1;
  							indices[ indexCount ++ ] = v3;
  							indices[ indexCount ++ ] = v4;
  						}
  					}
  				}
  
  				// increment only if a surface was used
  				surfCount ++;
  			}
  		}
  
  	  setIndex(indices);
  		setAttributeFromString( 'position', Float32BufferAttribute.fromList( vertices, 3 ) );
  		setAttributeFromString( 'normal', Float32BufferAttribute.fromList( normals, 3 ) );
  		setAttributeFromString( 'uv', Float32BufferAttribute.fromList( uvs, 2 ) );
  
  		computeBoundingSphere();
  	}
  }