Spaces:
Running
Running
File size: 7,222 Bytes
6cd9596 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 |
import { Vector3 } from './Vector3.js';
/**
* @author bhouston / http://clara.io
* @author mrdoob / http://mrdoob.com/
*/
function Triangle( a, b, c ) {
this.a = ( a !== undefined ) ? a : new Vector3();
this.b = ( b !== undefined ) ? b : new Vector3();
this.c = ( c !== undefined ) ? c : new Vector3();
}
Object.assign( Triangle, {
getNormal: function () {
var v0 = new Vector3();
return function getNormal( a, b, c, target ) {
if ( target === undefined ) {
console.warn( 'THREE.Triangle: .getNormal() target is now required' );
target = new Vector3();
}
target.subVectors( c, b );
v0.subVectors( a, b );
target.cross( v0 );
var targetLengthSq = target.lengthSq();
if ( targetLengthSq > 0 ) {
return target.multiplyScalar( 1 / Math.sqrt( targetLengthSq ) );
}
return target.set( 0, 0, 0 );
};
}(),
// static/instance method to calculate barycentric coordinates
// based on: http://www.blackpawn.com/texts/pointinpoly/default.html
getBarycoord: function () {
var v0 = new Vector3();
var v1 = new Vector3();
var v2 = new Vector3();
return function getBarycoord( point, a, b, c, target ) {
v0.subVectors( c, a );
v1.subVectors( b, a );
v2.subVectors( point, a );
var dot00 = v0.dot( v0 );
var dot01 = v0.dot( v1 );
var dot02 = v0.dot( v2 );
var dot11 = v1.dot( v1 );
var dot12 = v1.dot( v2 );
var denom = ( dot00 * dot11 - dot01 * dot01 );
if ( target === undefined ) {
console.warn( 'THREE.Triangle: .getBarycoord() target is now required' );
target = new Vector3();
}
// collinear or singular triangle
if ( denom === 0 ) {
// arbitrary location outside of triangle?
// not sure if this is the best idea, maybe should be returning undefined
return target.set( - 2, - 1, - 1 );
}
var invDenom = 1 / denom;
var u = ( dot11 * dot02 - dot01 * dot12 ) * invDenom;
var v = ( dot00 * dot12 - dot01 * dot02 ) * invDenom;
// barycentric coordinates must always sum to 1
return target.set( 1 - u - v, v, u );
};
}(),
containsPoint: function () {
var v1 = new Vector3();
return function containsPoint( point, a, b, c ) {
Triangle.getBarycoord( point, a, b, c, v1 );
return ( v1.x >= 0 ) && ( v1.y >= 0 ) && ( ( v1.x + v1.y ) <= 1 );
};
}(),
getUV: function () {
var barycoord = new Vector3();
return function getUV( point, p1, p2, p3, uv1, uv2, uv3, target ) {
this.getBarycoord( point, p1, p2, p3, barycoord );
target.set( 0, 0 );
target.addScaledVector( uv1, barycoord.x );
target.addScaledVector( uv2, barycoord.y );
target.addScaledVector( uv3, barycoord.z );
return target;
};
}()
} );
Object.assign( Triangle.prototype, {
set: function ( a, b, c ) {
this.a.copy( a );
this.b.copy( b );
this.c.copy( c );
return this;
},
setFromPointsAndIndices: function ( points, i0, i1, i2 ) {
this.a.copy( points[ i0 ] );
this.b.copy( points[ i1 ] );
this.c.copy( points[ i2 ] );
return this;
},
clone: function () {
return new this.constructor().copy( this );
},
copy: function ( triangle ) {
this.a.copy( triangle.a );
this.b.copy( triangle.b );
this.c.copy( triangle.c );
return this;
},
getArea: function () {
var v0 = new Vector3();
var v1 = new Vector3();
return function getArea() {
v0.subVectors( this.c, this.b );
v1.subVectors( this.a, this.b );
return v0.cross( v1 ).length() * 0.5;
};
}(),
getMidpoint: function ( target ) {
if ( target === undefined ) {
console.warn( 'THREE.Triangle: .getMidpoint() target is now required' );
target = new Vector3();
}
return target.addVectors( this.a, this.b ).add( this.c ).multiplyScalar( 1 / 3 );
},
getNormal: function ( target ) {
return Triangle.getNormal( this.a, this.b, this.c, target );
},
getPlane: function ( target ) {
if ( target === undefined ) {
console.warn( 'THREE.Triangle: .getPlane() target is now required' );
target = new Vector3();
}
return target.setFromCoplanarPoints( this.a, this.b, this.c );
},
getBarycoord: function ( point, target ) {
return Triangle.getBarycoord( point, this.a, this.b, this.c, target );
},
containsPoint: function ( point ) {
return Triangle.containsPoint( point, this.a, this.b, this.c );
},
getUV: function ( point, uv1, uv2, uv3, result ) {
return Triangle.getUV( point, this.a, this.b, this.c, uv1, uv2, uv3, result );
},
intersectsBox: function ( box ) {
return box.intersectsTriangle( this );
},
closestPointToPoint: function () {
var vab = new Vector3();
var vac = new Vector3();
var vbc = new Vector3();
var vap = new Vector3();
var vbp = new Vector3();
var vcp = new Vector3();
return function closestPointToPoint( p, target ) {
if ( target === undefined ) {
console.warn( 'THREE.Triangle: .closestPointToPoint() target is now required' );
target = new Vector3();
}
var a = this.a, b = this.b, c = this.c;
var v, w;
// algorithm thanks to Real-Time Collision Detection by Christer Ericson,
// published by Morgan Kaufmann Publishers, (c) 2005 Elsevier Inc.,
// under the accompanying license; see chapter 5.1.5 for detailed explanation.
// basically, we're distinguishing which of the voronoi regions of the triangle
// the point lies in with the minimum amount of redundant computation.
vab.subVectors( b, a );
vac.subVectors( c, a );
vap.subVectors( p, a );
var d1 = vab.dot( vap );
var d2 = vac.dot( vap );
if ( d1 <= 0 && d2 <= 0 ) {
// vertex region of A; barycentric coords (1, 0, 0)
return target.copy( a );
}
vbp.subVectors( p, b );
var d3 = vab.dot( vbp );
var d4 = vac.dot( vbp );
if ( d3 >= 0 && d4 <= d3 ) {
// vertex region of B; barycentric coords (0, 1, 0)
return target.copy( b );
}
var vc = d1 * d4 - d3 * d2;
if ( vc <= 0 && d1 >= 0 && d3 <= 0 ) {
v = d1 / ( d1 - d3 );
// edge region of AB; barycentric coords (1-v, v, 0)
return target.copy( a ).addScaledVector( vab, v );
}
vcp.subVectors( p, c );
var d5 = vab.dot( vcp );
var d6 = vac.dot( vcp );
if ( d6 >= 0 && d5 <= d6 ) {
// vertex region of C; barycentric coords (0, 0, 1)
return target.copy( c );
}
var vb = d5 * d2 - d1 * d6;
if ( vb <= 0 && d2 >= 0 && d6 <= 0 ) {
w = d2 / ( d2 - d6 );
// edge region of AC; barycentric coords (1-w, 0, w)
return target.copy( a ).addScaledVector( vac, w );
}
var va = d3 * d6 - d5 * d4;
if ( va <= 0 && ( d4 - d3 ) >= 0 && ( d5 - d6 ) >= 0 ) {
vbc.subVectors( c, b );
w = ( d4 - d3 ) / ( ( d4 - d3 ) + ( d5 - d6 ) );
// edge region of BC; barycentric coords (0, 1-w, w)
return target.copy( b ).addScaledVector( vbc, w ); // edge region of BC
}
// face region
var denom = 1 / ( va + vb + vc );
// u = va * denom
v = vb * denom;
w = vc * denom;
return target.copy( a ).addScaledVector( vab, v ).addScaledVector( vac, w );
};
}(),
equals: function ( triangle ) {
return triangle.a.equals( this.a ) && triangle.b.equals( this.b ) && triangle.c.equals( this.c );
}
} );
export { Triangle };
|