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/**
*
* Tessellates the famous Utah teapot database by Martin Newell into triangles.
*
* THREE.TeapotBufferGeometry = function ( size, segments, bottom, lid, body, fitLid, blinn )
*
* defaults: 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.
*
* 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
*
*
*
*/
/*global THREE */
THREE.TeapotBufferGeometry = function ( size, segments, bottom, lid, body, fitLid, blinn ) {
"use strict";
// 32 * 4 * 4 Bezier spline patches
var 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
] ;
var 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
] ;
THREE.BufferGeometry.call( this );
this.type = 'TeapotBufferGeometry';
this.parameters = {
size: size,
segments: segments,
bottom: bottom,
lid: lid,
body: body,
fitLid: fitLid,
blinn: blinn
};
size = size || 50;
// number of segments per patch
segments = segments !== undefined ? Math.max( 2, Math.floor( segments ) || 10 ) : 10;
// which parts should be visible
bottom = bottom === undefined ? true : bottom;
lid = lid === undefined ? true : lid;
body = body === undefined ? true : body;
// Should the lid be snug? It's not traditional, but we make it snug by default
fitLid = fitLid === undefined ? true : fitLid;
// Jim Blinn scaled the teapot down in size by about 1.3 for
// some rendering tests. He liked the new 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.
var blinnScale = 1.3;
blinn = blinn === undefined ? true : blinn;
// scale the size to be the real scaling factor
var maxHeight = 3.15 * ( blinn ? 1 : blinnScale );
var maxHeight2 = maxHeight / 2;
var trueSize = size / maxHeight2;
// Number of elements depends on what is needed. Subtract degenerate
// triangles at tip of bottom and lid out in advance.
var numTriangles = bottom ? ( 8 * segments - 4 ) * segments : 0;
numTriangles += lid ? ( 16 * segments - 4 ) * segments : 0;
numTriangles += body ? 40 * segments * segments : 0;
var indices = new Uint32Array( numTriangles * 3 );
var numVertices = bottom ? 4 : 0;
numVertices += lid ? 8 : 0;
numVertices += body ? 20 : 0;
numVertices *= ( segments + 1 ) * ( segments + 1 );
var vertices = new Float32Array( numVertices * 3 );
var normals = new Float32Array( numVertices * 3 );
var uvs = new Float32Array( numVertices * 2 );
// Bezier form
var ms = new THREE.Matrix4();
ms.set( -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 ) ;
var g = [];
var i, r, c;
var sp = [];
var tp = [];
var dsp = [];
var dtp = [];
// M * G * M matrix, sort of see
var mgm = [];
var vert = [];
var sdir = [];
var tdir = [];
var norm = new THREE.Vector3();
var tcoord;
var sstep, tstep;
var vertPerRow;
var s, t, sval, tval, p;
var dsval = 0;
var dtval = 0;
var normOut = new THREE.Vector3();
var v1, v2, v3, v4;
var gmx = new THREE.Matrix4();
var tmtx = new THREE.Matrix4();
var vsp = new THREE.Vector4();
var vtp = new THREE.Vector4();
var vdsp = new THREE.Vector4();
var vdtp = new THREE.Vector4();
var vsdir = new THREE.Vector3();
var vtdir = new THREE.Vector3();
var 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.
var notDegenerate = function ( vtx1, vtx2, vtx3 ) {
// if any vertex matches, return false
return ! ( ( ( 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 ( i = 0; i < 3; i ++ )
{
mgm[ i ] = new THREE.Matrix4();
}
var minPatches = body ? 0 : 20;
var maxPatches = bottom ? 32 : 28;
vertPerRow = segments + 1;
var surfCount = 0;
var vertCount = 0;
var normCount = 0;
var uvCount = 0;
var indexCount = 0;
for ( var 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 ( i = 0 ; i < 3 ; i ++ ) {
// get control patches
for ( r = 0 ; r < 4 ; r ++ ) {
for ( 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.set( 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.multiplyMatrices( gmx, ms );
mgm[ i ].multiplyMatrices( mst, tmtx );
}
// step along, get points, and output
for ( sstep = 0 ; sstep <= segments ; sstep ++ ) {
s = sstep / segments;
for ( tstep = 0 ; tstep <= segments ; tstep ++ ) {
t = tstep / segments;
// point from basis
// get power vectors and their derivatives
for ( p = 4, sval = tval = 1.0 ; 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.fromArray( sp );
vtp.fromArray( tp );
vdsp.fromArray( dsp );
vdtp.fromArray( dtp );
// do for x,y,z
for ( 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.fromArray( sdir );
vtdir.fromArray( tdir );
norm.crossVectors( 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.set( 0, vert[ 2 ] > maxHeight2 ? 1 : - 1, 0 );
}
else
{
// standard output: rotate on X axis
normOut.set( 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 ( sstep = 0 ; sstep < segments ; sstep ++ ) {
for ( tstep = 0 ; tstep < segments ; tstep ++ ) {
v1 = surfCount * vertPerRow * vertPerRow + sstep * vertPerRow + tstep;
v2 = v1 + 1;
v3 = v2 + vertPerRow;
v4 = v1 + vertPerRow;
// Normals and UVs cannot be shared. Without clone(), you can see the consequences
// of sharing if you call geometry.applyMatrix( 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 ++;
}
}
this.setIndex( new THREE.BufferAttribute( indices, 1 ) );
this.addAttribute( 'position', new THREE.BufferAttribute( vertices, 3 ) );
this.addAttribute( 'normal', new THREE.BufferAttribute( normals, 3 ) );
this.addAttribute( 'uv', new THREE.BufferAttribute( uvs, 2 ) );
this.computeBoundingSphere();
};
THREE.TeapotBufferGeometry.prototype = Object.create( THREE.BufferGeometry.prototype );
THREE.TeapotBufferGeometry.prototype.constructor = THREE.TeapotBufferGeometry;
THREE.TeapotBufferGeometry.prototype.clone = function () {
var bufferGeometry = new THREE.TeapotBufferGeometry(
this.parameters.size,
this.parameters.segments,
this.parameters.bottom,
this.parameters.lid,
this.parameters.body,
this.parameters.fitLid,
this.parameters.blinn
);
return bufferGeometry;
};