1169:
1126:
31:
1044:, where paths are generated starting from the camera and bouncing around the scene until they encounter a light source. This is referred to as "backwards" because starting paths from the camera and moving towards the light source is opposite the direction that the light is actually traveling. It still produces the same result because all optical systems are reversible.
1149:
more rays in directions in which the luminance would have been greater anyway. If the density of rays cast in certain directions matches the strength of contributions in those directions, the result is identical, but far fewer rays were actually cast. Importance sampling is used to match ray density to
1095:
Bidirectional path tracing provides an algorithm that combines the two approaches and can produce lower variance than either method alone. For each sample, two paths are traced independently: one using from the light source and one from the camera. This produces a set of possible sampling strategies,
962:
to obtain the output color. Note this method of always sampling a random ray in the normal's hemisphere only works well for perfectly diffuse surfaces. For other materials, one generally has to use importance sampling, i.e. probabilistically select a new ray according to the BRDF's distribution. For
1148:
The central performance bottleneck in path tracing is the complex geometrical calculation of casting a ray. Importance sampling is a technique which is motivated to cast fewer rays through the scene while still converging correctly to outgoing luminance on the surface point. This is done by casting
326:
Kajiya's equation is a complete summary of these three principles, and path tracing, which approximates a solution to the equation, remains faithful to them in its implementation. There are other principles of optics which are not the focus of Kajiya's equation, and therefore are often difficult or
1159:
can result in a lower-noise image with fewer samples. This algorithm was created in order to get faster convergence in scenes in which the light must pass through odd corridors or small holes in order to reach the part of the scene that the camera is viewing. It has also shown promise in correctly
963:
instance, a perfectly specular (mirror) material would not work with the method above, as the probability of the new ray being the correct reflected ray – which is the only ray through which any radiance will be reflected – is zero. In these situations, one must divide the reflectance by the
309:, or "perfectly diffuse". While radiosity received a lot of attention at its introduction, perfectly diffuse surfaces do not exist in the real world. The realization that scattering from a surface depends on both incoming and outgoing directions is the key principle behind the
1082:
cannot be used to sample these paths directly from the diffuse surface, because the specular interaction is in the middle. Likewise, it cannot be used to sample paths from the specular surface because there is only one direction that the light can bounce.
277:
adheres to three particular principles of optics; the
Principle of Global Illumination, the Principle of Equivalence (reflected light is equivalent to emitted light), and the Principle of Direction (reflected light and scattered light have a direction).
1160:
rendering pathological situations with caustics. Instead of generating random paths, new sampling paths are created as slight mutations of existing ones. In this sense, the algorithm "remembers" the successful paths from light sources to the camera.
1112:, it is connecting the vertices of the light path to the first vertex of the camera path. In addition, there are several completely new sampling strategies, where intermediate vertices are connected. Weighting all of these sampling strategies using
1141:. The image starts to become recognizable after only a few samples per pixel, perhaps 100. However, for the image to "converge" and reduce noise to acceptable levels usually takes around 5000 samples for most images, and many more for
1116:
creates a new sampler that can converge faster than unidirectional path tracing, even though more work is required for each sample. This works particularly well for caustics or scenes that are lit primarily through indirect lighting.
1087:
has a similar issue when paths interact with a specular surface before hitting the camera. Because this situation is significantly more common, and noisy (or completely black) glass objects are very visually disruptive,
1184:. A path tracer can take full advantage of complex, carefully modeled or measured distribution functions, which controls the appearance ("material", "texture", or "shading" in computer graphics terms) of an object.
281:
In the real world, objects and surfaces are visible due to the fact that they are reflecting light. This reflected light then illuminates other objects in turn. From that simple observation, two principles follow.
197:
demonstrated the first commercial implementation of a path tracer running on a GPU , and other implementations have followed, such as that of
Vladimir Koylazov in August 2009. This was aided by the maturing of
323:
The illumination coming from surfaces must scatter in a particular direction that is some function of the incoming direction of the arriving illumination, and the outgoing direction being sampled.
1338:
is an educational path tracer by Kevin Beason. It uses 99 lines of C++ (including scene description). This page has a good set of examples of noise resulting from this technique.
997:
1027:
1002:
There are other considerations to take into account to ensure conservation of energy. In particular, in the naive case, the reflectance of a diffuse BRDF must not exceed
1070:) instead of waiting for a path to hit it by chance. This technique is usually effective, but becomes less useful when specular or near-specular BRDFs are present. For
72:
of surfaces, accurate models of real light sources, and optically correct cameras, path tracing can produce still images that are indistinguishable from photographs.
68:) to determine how much of it will go towards the viewpoint camera. This integration procedure is repeated for every pixel in the output image. When combined with
317:
throughout the 1990s, since accounting for direction always exacted a price of steep increases in calculation times on desktop computers. Principle III follows.
107:, and indirect lighting. Implementation of a renderer including these effects is correspondingly simpler. An extended version of the algorithm is realized by
372:
is a procedure for performing naive path tracing. The TracePath function calculates a single sample of a pixel, where only the
Gathering Path is considered.
189:
have become powerful enough to render images more quickly, causing more widespread interest in path tracing algorithms. Tim
Purcell first presented a
314:
151:
967:
of the sampling scheme, as per Monte Carlo integration (in the naive case above, there is no particular sampling scheme, so the PDF turns out to be
1177:
310:
174:, a method of perturbing previously found paths in order to increase performance for difficult scenes, was introduced in 1997 by Eric Veach and
1181:
1129:
Noise decreases as the number of samples per pixel increase. The top left shows 1 sample per pixel, and doubles from left to right each square.
126:. However, the path tracing algorithm is relatively inefficient: A very large number of rays must be traced to get high-quality images free of
1029:
or the object will reflect more light than it receives (this however depends on the sampling scheme used, and can be difficult to get right).
327:
incorrectly simulated by the algorithm. Path tracing is confounded by optical phenomena not contained in the three principles. For example,
1366:
1258:
294:
Second, there is no distinction to be made between illumination emitted from a light source and illumination reflected from a surface.
168:
to the integral of the rendering equation. A decade later, Lafortune suggested many refinements, including bidirectional path tracing.
1113:
122:
nature, and algorithmic simplicity, path tracing is used to generate reference images when testing the quality of other rendering
1792:
1145:
cases. Noise is particularly a problem for animations, giving them a normally unwanted "film grain" quality of random speckling.
1755:
1728:
64:
arriving to a single point on the surface of an object. This illuminance is then reduced by a surface reflectance function (
1771:
1375:
1054:), where paths are generated starting from the light sources and bouncing around the scene until they encounter the camera.
1306:
130:. Several variants have been introduced which are more efficient than the original algorithm for many scenes, including
1495:
301:
was faithful to both principles. However, radiosity relates the total illuminance falling on a surface with a uniform
235:
with their proprietary CGI Studio path tracing renderer, featuring soft shadows and indirect illumination effects.
1359:
1062:
can be used to reduce variance. This works by directly sampling an important feature (the camera in the case of
1618:
1419:
1078:
paths that interact with a diffuse surface, then bounce off a specular surface before hitting a light source.
1743:
1733:
1623:
1442:
298:
248:
243:
was, in 2006, the first animated feature film to be rendered entirely in a path tracer, using the commercial
49:
1738:
1603:
1543:
964:
970:
1531:
1352:
1156:
1142:
1108:, it is connecting the vertices of the camera path directly to the first vertex of the light path. For
1005:
288:
For a given indoor scene, every object in the room must contribute illumination to every other object.
171:
139:
69:
1096:
where every vertex of one path can be connected directly to every vertex of the other. The original
1245:
236:
21:
1268:
Purcell, T J; Buck, I; Mark, W; and
Hanrahan, P, "Ray Tracing on Programmable Graphics Hardware",
1168:
1150:
258:
165:
135:
108:
57:
1750:
1700:
1665:
1643:
1638:
1240:
306:
80:
1593:
1572:
1516:
342:
1284:
251:
has been using its own optimized path tracer known as
Hyperion ever since the production of
217:
Path tracing has played an important role in the film industry. Earlier films had relied on
1476:
1462:
1406:
348:
240:
8:
1608:
1536:
1424:
1237:
Proceedings of the 13th annual conference on
Computer graphics and interactive techniques
190:
53:
1670:
1658:
1505:
1500:
1452:
1273:
1198:
1176:
The reflective properties (amount, direction, and color) of surfaces are modeled using
274:
218:
175:
157:
119:
84:
45:
1329:
1037:
Sampling the integral can be done by either of the following two distinct approaches:
1720:
1613:
1598:
1414:
1193:
253:
244:
230:
104:
42:
34:
An image rendered using path tracing, demonstrating notable features of the technique
1705:
1695:
1577:
1565:
1075:
332:
222:
112:
100:
1526:
1391:
1383:
1213:
959:
1180:. The equivalent for transmitted light (light that goes through the object) are
1675:
1125:
92:
79:
many effects that have to be specifically added to other methods (conventional
1294:
1786:
1680:
1554:
1484:
1259:
Mathematical Models and Monte Carlo
Algorithms for Physically Based Rendering
1208:
1092:
is the only method that is used for unidirectional path tracing in practice.
226:
152:
Rendering (computer graphics) § Chronology of important published ideas
1685:
1633:
1628:
1548:
1489:
352:
313:(BRDF). This direction dependence was a focus of research resulting in the
161:
1653:
1521:
1457:
356:
127:
96:
61:
193:
algorithm running on a GPU in 2002. In
February 2009, Austin Robison of
369:
17:
1335:
1218:
302:
262:
123:
1344:
164:
in 1986. Path tracing was introduced then as an algorithm to find a
1511:
336:
76:
30:
1560:
650:// Compute the BRDF for this ray (assuming Lambertian reflection)
88:
1690:
1447:
207:
194:
1710:
1396:
1297:; Other examples include Octane Render, Arion, and Luxrender.
1138:
1134:
211:
199:
1307:"Disney's new Production Renderer 'Hyperion' – Yes, Disney!"
1434:
1104:
algorithms are both special cases of these strategies. For
203:
65:
186:
182:
305:
that leaves the surface. This forced all surfaces to be
56:
is faithful to reality. Fundamentally, the algorithm is
1285:"Interactive Ray Tracing on the GPU and NVIRT Overview"
1253:
1008:
973:
221:
to produce CG visual effects and animation. In 1998,
1163:
545:// Pick a random direction from here and keep going.
1290:
297:Invented in 1984, a rather different method called
1021:
991:
160:and its use in computer graphics was presented by
1205:, a path tracing GPU-accelerated rendering engine
261:has also adopted path tracing for its commercial
52:images of three-dimensional scenes such that the
1784:
1324:
1235:Kajiya, J. T. (1986). "The rendering equation".
1230:
1332:. In SIGGRAPH’97 (August 1997), pp. 65–76.
311:bidirectional reflectance distribution function
131:
581:// This is NOT a cosine-weighted distribution!
339:scales by the density of illuminance in space.
1360:
1032:
719:// Recursively trace reflected light sources.
1300:
1264:
1367:
1353:
1279:
1244:
1167:
1124:
29:
1785:
1234:
1374:
1348:
755:// Apply the Rendering Equation here.
359:; light is a spectrum of frequencies.
345:; a violation of Principle III above.
1772:List of computer graphics algorithms
1433:
1304:
1133:A path tracer continuously samples
1066:, or a light source in the case of
13:
1272:, 703 – 712. See also Purcell, T,
1058:In both cases, a technique called
992:{\displaystyle {\frac {1}{2\pi }}}
14:
1804:
1274:Ray tracing on a stream processor
1172:Scattering distribution functions
1164:Scattering distribution functions
1074:, this creates high variance for
1022:{\displaystyle {\frac {1}{\pi }}}
210:and GPU ray tracing SDKs such as
1153:, and also used to match BRDFs.
16:For tracing network paths, see
1793:Global illumination algorithms
1120:
596:RandomUnitVectorInHemisphereOf
315:publication of important ideas
268:
1:
1729:3D computer graphics software
1328:Veach, E., and Guibas, L. J.
1201:– 3D program that integrates
249:Walt Disney Animation Studios
202:programming toolkits such as
1544:Hidden-surface determination
1114:multiple importance sampling
965:probability density function
614:// Probability of the newRay
363:
7:
1187:
10:
1809:
1330:Metropolis light transport
1157:Metropolis light transport
1033:Bidirectional path tracing
172:Metropolis light transport
149:
145:
140:Metropolis light transport
132:bidirectional path tracing
70:physically accurate models
15:
1764:
1719:
1586:
1475:
1405:
1382:
958:All the samples are then
1224:
437:// Bounced enough times.
374:
237:Sony Pictures Imageworks
27:Computer graphics method
22:Tracing (disambiguation)
1756:Vector graphics editors
1751:Raster graphics editors
259:Pixar Animation Studios
136:volumetric path tracing
109:volumetric path tracing
75:Path tracing naturally
1639:Checkerboard rendering
1173:
1130:
1110:backwards path tracing
1102:backwards path tracing
1090:backwards path tracing
1072:backwards path tracing
1068:backwards path tracing
1042:Backwards path tracing
1023:
993:
111:, which considers the
35:
20:. For other uses, see
1594:Affine transformation
1573:Surface triangulation
1517:Anisotropic filtering
1287:, slide 37, I3D 2009.
1261:, (PhD thesis), 1996.
1171:
1128:
1080:Next event estimation
1060:next event estimation
1052:forwards path tracing
1024:
994:
343:Subsurface scattering
150:Further information:
118:Due to its accuracy,
33:
1151:Lambert's cosine law
1006:
971:
686:normalWhereObjWasHit
608:normalWhereObjWasHit
349:Chromatic aberration
229:-winning short film
1609:Collision detection
1537:Global illumination
1276:(PhD thesis), 2004.
1270:Proc. SIGGRAPH 2002
947:// Average samples.
575:pointWhereObjWasHit
491:// Nothing was hit.
191:global illumination
54:global illumination
1659:Scanline rendering
1453:Parallax scrolling
1443:Isometric graphics
1199:Blender (software)
1174:
1131:
1019:
989:
275:rendering equation
219:scanline rendering
176:Leonidas J. Guibas
166:numerical solution
158:rendering equation
85:scanline rendering
46:Monte Carlo method
36:
1780:
1779:
1721:Graphics software
1614:Planar projection
1599:Back-face culling
1471:
1470:
1415:Alpha compositing
1376:Computer graphics
1283:Robison, Austin,
1194:Arnold (software)
1017:
987:
449:FindNearestObject
105:ambient occlusion
43:computer graphics
1800:
1706:Volume rendering
1578:Wire-frame model
1431:
1430:
1369:
1362:
1355:
1346:
1345:
1327:
1321:
1319:
1317:
1303:
1293:
1282:
1267:
1256:
1250:
1248:
1233:
1028:
1026:
1025:
1020:
1018:
1010:
998:
996:
995:
990:
988:
986:
975:
954:
951:
948:
945:
942:
939:
936:
933:
930:
927:
924:
921:
918:
915:
912:
909:
906:
903:
900:
897:
894:
891:
888:
885:
882:
879:
876:
873:
870:
867:
864:
861:
858:
855:
852:
849:
846:
843:
840:
837:
834:
831:
828:
825:
822:
819:
816:
813:
810:
807:
804:
801:
798:
795:
792:
789:
786:
783:
780:
777:
774:
771:
768:
765:
762:
759:
756:
753:
750:
747:
744:
741:
738:
735:
732:
729:
726:
723:
720:
717:
714:
711:
708:
705:
702:
699:
696:
693:
690:
687:
684:
681:
678:
675:
672:
669:
666:
663:
660:
657:
654:
651:
648:
645:
642:
639:
636:
633:
630:
627:
624:
621:
618:
615:
612:
609:
606:
603:
600:
597:
594:
591:
588:
585:
582:
579:
576:
573:
570:
567:
564:
561:
558:
555:
552:
549:
546:
543:
540:
537:
534:
531:
528:
525:
522:
519:
516:
513:
510:
507:
504:
501:
498:
495:
492:
489:
486:
483:
480:
477:
474:
471:
468:
465:
462:
459:
456:
453:
450:
447:
444:
441:
438:
435:
432:
429:
426:
423:
420:
417:
414:
411:
408:
405:
402:
399:
396:
393:
390:
387:
384:
381:
378:
247:renderer. Also,
223:Blue Sky Studios
113:light scattering
87:), such as soft
1808:
1807:
1803:
1802:
1801:
1799:
1798:
1797:
1783:
1782:
1781:
1776:
1760:
1715:
1582:
1527:Fluid animation
1467:
1429:
1401:
1392:Diffusion curve
1384:Vector graphics
1378:
1373:
1342:
1315:
1313:
1305:Seymour, Mike.
1227:
1219:LuxCoreRenderer
1214:Pixar RenderMan
1190:
1166:
1123:
1035:
1009:
1007:
1004:
1003:
979:
974:
972:
969:
968:
956:
955:
952:
949:
946:
943:
940:
937:
934:
931:
928:
925:
922:
919:
916:
913:
910:
907:
904:
901:
898:
895:
892:
889:
886:
883:
880:
877:
874:
871:
868:
865:
862:
859:
856:
853:
850:
847:
844:
841:
838:
835:
832:
829:
826:
823:
820:
817:
814:
811:
808:
805:
802:
799:
796:
793:
790:
787:
784:
781:
778:
775:
772:
769:
766:
763:
760:
757:
754:
751:
748:
745:
742:
739:
736:
733:
730:
727:
724:
721:
718:
715:
712:
709:
706:
703:
700:
697:
694:
691:
688:
685:
682:
679:
676:
673:
670:
667:
664:
661:
658:
655:
652:
649:
646:
643:
640:
637:
634:
631:
628:
625:
622:
619:
616:
613:
610:
607:
604:
601:
598:
595:
592:
589:
586:
583:
580:
577:
574:
571:
568:
565:
562:
559:
556:
553:
550:
547:
544:
541:
538:
535:
532:
529:
526:
523:
520:
517:
514:
511:
508:
505:
502:
499:
496:
493:
490:
487:
484:
481:
478:
475:
472:
469:
466:
463:
460:
457:
454:
451:
448:
445:
442:
439:
436:
433:
430:
427:
424:
421:
418:
415:
412:
409:
406:
403:
400:
397:
394:
391:
388:
385:
382:
379:
376:
366:
271:
181:More recently,
154:
148:
128:noise artifacts
28:
25:
12:
11:
5:
1806:
1796:
1795:
1778:
1777:
1775:
1774:
1768:
1766:
1762:
1761:
1759:
1758:
1753:
1748:
1747:
1746:
1741:
1736:
1725:
1723:
1717:
1716:
1714:
1713:
1708:
1703:
1698:
1693:
1688:
1683:
1678:
1676:Shadow mapping
1673:
1668:
1663:
1662:
1661:
1656:
1651:
1646:
1641:
1636:
1631:
1621:
1616:
1611:
1606:
1601:
1596:
1590:
1588:
1584:
1583:
1581:
1580:
1575:
1570:
1569:
1568:
1558:
1551:
1546:
1541:
1540:
1539:
1529:
1524:
1519:
1514:
1509:
1503:
1498:
1492:
1487:
1481:
1479:
1473:
1472:
1469:
1468:
1466:
1465:
1460:
1455:
1450:
1445:
1439:
1437:
1428:
1427:
1422:
1417:
1411:
1409:
1403:
1402:
1400:
1399:
1394:
1388:
1386:
1380:
1379:
1372:
1371:
1364:
1357:
1349:
1340:
1339:
1333:
1322:
1298:
1288:
1277:
1262:
1257:Lafortune, E,
1251:
1246:10.1.1.63.1402
1226:
1223:
1222:
1221:
1216:
1211:
1206:
1196:
1189:
1186:
1165:
1162:
1122:
1119:
1056:
1055:
1045:
1034:
1031:
1016:
1013:
985:
982:
978:
375:
368:The following
365:
362:
361:
360:
346:
340:
331:Bright, sharp
270:
267:
147:
144:
93:depth of field
26:
9:
6:
4:
3:
2:
1805:
1794:
1791:
1790:
1788:
1773:
1770:
1769:
1767:
1763:
1757:
1754:
1752:
1749:
1745:
1742:
1740:
1737:
1735:
1732:
1731:
1730:
1727:
1726:
1724:
1722:
1718:
1712:
1709:
1707:
1704:
1702:
1699:
1697:
1694:
1692:
1689:
1687:
1684:
1682:
1681:Shadow volume
1679:
1677:
1674:
1672:
1669:
1667:
1664:
1660:
1657:
1655:
1652:
1650:
1647:
1645:
1642:
1640:
1637:
1635:
1632:
1630:
1627:
1626:
1625:
1622:
1620:
1617:
1615:
1612:
1610:
1607:
1605:
1602:
1600:
1597:
1595:
1592:
1591:
1589:
1585:
1579:
1576:
1574:
1571:
1567:
1564:
1563:
1562:
1559:
1556:
1555:Triangle mesh
1552:
1550:
1547:
1545:
1542:
1538:
1535:
1534:
1533:
1530:
1528:
1525:
1523:
1520:
1518:
1515:
1513:
1510:
1507:
1504:
1502:
1499:
1497:
1493:
1491:
1488:
1486:
1485:3D projection
1483:
1482:
1480:
1478:
1474:
1464:
1461:
1459:
1456:
1454:
1451:
1449:
1446:
1444:
1441:
1440:
1438:
1436:
1432:
1426:
1425:Text-to-image
1423:
1421:
1418:
1416:
1413:
1412:
1410:
1408:
1404:
1398:
1395:
1393:
1390:
1389:
1387:
1385:
1381:
1377:
1370:
1365:
1363:
1358:
1356:
1351:
1350:
1347:
1343:
1337:
1334:
1331:
1326:
1323:
1312:
1308:
1302:
1299:
1296:
1292:
1289:
1286:
1281:
1278:
1275:
1271:
1266:
1263:
1260:
1255:
1252:
1247:
1242:
1238:
1232:
1229:
1228:
1220:
1217:
1215:
1212:
1210:
1209:Octane Render
1207:
1204:
1200:
1197:
1195:
1192:
1191:
1185:
1183:
1179:
1170:
1161:
1158:
1154:
1152:
1146:
1144:
1140:
1136:
1127:
1118:
1115:
1111:
1107:
1106:light tracing
1103:
1099:
1098:light tracing
1093:
1091:
1086:
1085:Light tracing
1081:
1077:
1073:
1069:
1065:
1064:light tracing
1061:
1053:
1049:
1048:Light tracing
1046:
1043:
1040:
1039:
1038:
1030:
1014:
1011:
1000:
983:
980:
976:
966:
961:
373:
371:
358:
354:
350:
347:
344:
341:
338:
334:
330:
329:
328:
324:
322:
318:
316:
312:
308:
304:
300:
295:
293:
289:
287:
283:
279:
276:
266:
264:
260:
256:
255:
250:
246:
242:
241:Monster House
238:
234:
233:
228:
227:Academy Award
225:rendered the
224:
220:
215:
213:
209:
205:
201:
196:
192:
188:
184:
179:
177:
173:
169:
167:
163:
159:
153:
143:
141:
137:
133:
129:
125:
121:
116:
114:
110:
106:
102:
98:
94:
90:
86:
82:
78:
73:
71:
67:
63:
60:over all the
59:
55:
51:
47:
44:
40:
32:
23:
19:
1686:Shear matrix
1649:Path tracing
1648:
1634:Cone tracing
1629:Beam tracing
1549:Polygon mesh
1490:3D rendering
1341:
1325:
1316:16 September
1314:. Retrieved
1310:
1301:
1291:
1280:
1269:
1265:
1254:
1236:
1231:
1202:
1175:
1155:
1147:
1143:pathological
1132:
1109:
1105:
1101:
1097:
1094:
1089:
1084:
1079:
1071:
1067:
1063:
1059:
1057:
1051:
1047:
1041:
1036:
1001:
957:
467:hitSomething
367:
353:fluorescence
325:
320:
319:
296:
291:
290:
285:
284:
280:
272:
252:
231:
216:
180:
170:
162:James Kajiya
155:
117:
115:of a scene.
74:
39:Path tracing
38:
37:
1701:Translation
1654:Ray casting
1644:Ray tracing
1522:Cel shading
1496:Image-based
1477:3D graphics
1458:Ray casting
1407:2D graphics
1121:Performance
884:generateRay
707:reflectance
357:iridescence
269:Description
97:motion blur
81:ray tracing
62:illuminance
58:integrating
1765:Algorithms
1619:Reflection
941:numSamples
860:numSamples
839:finalImage
818:numSamples
809:finalImage
662:DotProduct
370:pseudocode
307:Lambertian
265:renderer.
254:Big Hero 6
124:algorithms
18:traceroute
1744:rendering
1734:animation
1624:Rendering
1295:Vray demo
1241:CiteSeerX
1015:π
984:π
908:TracePath
782:cos_theta
761:emittance
731:TracePath
674:direction
656:cos_theta
590:direction
539:emittance
527:emittance
380:TracePath
364:Algorithm
303:luminance
299:radiosity
273:Kajiya's
263:RenderMan
257:in 2014.
77:simulates
50:rendering
1787:Category
1739:modeling
1666:Rotation
1604:Clipping
1587:Concepts
1566:Deferred
1532:Lighting
1512:Aliasing
1506:Unbiased
1501:Spectral
1188:See also
960:averaged
776:incoming
725:incoming
701:material
533:material
518:material
512:thingHit
500:material
497:Material
419:MaxDepth
337:radiance
333:caustics
120:unbiased
101:caustics
1671:Scaling
1561:Shading
1336:SmallPt
1311:fxguide
1239:. ACM.
1076:caustic
848:foreach
827:foreach
146:History
89:shadows
1691:Shader
1463:Skybox
1448:Mode 7
1420:Layers
1243:
1203:Cycles
1137:of an
1135:pixels
878:camera
800:Render
758:return
737:newRay
668:newRay
584:newRay
563:origin
557:newRay
551:newRay
482:return
428:return
245:Arnold
208:OpenCL
195:Nvidia
138:, and
1711:Voxel
1696:Texel
1397:Pixel
1225:Notes
1182:BSDFs
1178:BRDFs
1139:image
935:color
929:pixel
902:color
896:pixel
890:pixel
833:pixel
815:count
806:Image
743:depth
722:Color
692:Color
653:float
620:float
617:const
524:Color
515:->
485:Black
473:false
431:Black
416:>=
413:depth
398:depth
395:count
377:Color
232:Bunny
212:OptiX
200:GPGPU
41:is a
1435:2.5D
1318:2017
1100:and
1050:(or
797:void
770:BRDF
695:BRDF
321:III.
206:and
204:CUDA
187:GPUs
185:and
183:CPUs
156:The
66:BRDF
999:).
869:Ray
680:ray
602:ray
569:ray
548:Ray
506:ray
461:ray
452:();
443:ray
389:ray
386:Ray
292:II.
83:or
48:of
1789::
1309:.
938:/=
923:);
905:+=
893:);
857:in
836:in
791:);
752:);
713:PI
689:);
647:);
644:PI
611:);
470:==
455:if
407:if
355:,
351:,
335:;
286:I.
239:'
214:.
178:.
142:.
134:,
103:,
99:,
95:,
91:,
1557:)
1553:(
1508:)
1494:(
1368:e
1361:t
1354:v
1320:.
1249:.
1012:1
981:2
977:1
953:}
950:}
944:;
932:.
926:}
920:0
917:,
914:r
911:(
899:.
887:(
881:.
875:=
872:r
866:{
863:)
854:i
851:(
845:{
842:)
830:(
824:{
821:)
812:,
803:(
794:}
788:p
785:/
779:*
773:*
767:(
764:+
749:1
746:+
740:,
734:(
728:=
716:;
710:/
704:.
698:=
683:.
677:,
671:.
665:(
659:=
641:*
638:2
635:(
632:/
629:1
626:=
623:p
605:.
599:(
593:=
587:.
578:;
572:.
566:=
560:.
554:;
542:;
536:.
530:=
521:;
509:.
503:=
494:}
488:;
479:{
476:)
464:.
458:(
446:.
440:}
434:;
425:{
422:)
410:(
404:{
401:)
392:,
383:(
24:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
