forked from bartvdbraak/blender
7c9d993347
without SSE3 support, due to 80 bit precision float register being used for one bounding box but not the one next to it.
1174 lines
33 KiB
C
1174 lines
33 KiB
C
/*
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* Adapted from code Copyright 2009-2010 NVIDIA Corporation
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* Modifications Copyright 2011, Blender Foundation.
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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CCL_NAMESPACE_BEGIN
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/*
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* "Persistent while-while kernel" used in:
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*
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* "Understanding the Efficiency of Ray Traversal on GPUs",
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* Timo Aila and Samuli Laine,
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* Proc. High-Performance Graphics 2009
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*/
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/* bottom-most stack entry, indicating the end of traversal */
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#define ENTRYPOINT_SENTINEL 0x76543210
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/* 64 object BVH + 64 mesh BVH + 64 object node splitting */
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#define BVH_STACK_SIZE 192
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#define BVH_NODE_SIZE 4
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#define TRI_NODE_SIZE 3
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/* silly workaround for float extended precision that happens when compiling
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* without sse support on x86, it results in different results for float ops
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* that you would otherwise expect to compare correctly */
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#if !defined(__i386__) || defined(__SSE__)
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#define NO_EXTENDED_PRECISION
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#else
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#define NO_EXTENDED_PRECISION volatile
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#endif
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__device_inline float3 bvh_inverse_direction(float3 dir)
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{
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/* avoid divide by zero (ooeps = exp2f(-80.0f)) */
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float ooeps = 0.00000000000000000000000082718061255302767487140869206996285356581211090087890625f;
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float3 idir;
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idir.x = 1.0f/((fabsf(dir.x) > ooeps)? dir.x: copysignf(ooeps, dir.x));
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idir.y = 1.0f/((fabsf(dir.y) > ooeps)? dir.y: copysignf(ooeps, dir.y));
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idir.z = 1.0f/((fabsf(dir.z) > ooeps)? dir.z: copysignf(ooeps, dir.z));
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return idir;
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}
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__device_inline void bvh_instance_push(KernelGlobals *kg, int object, const Ray *ray, float3 *P, float3 *idir, float *t, const float tmax)
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{
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Transform tfm = object_fetch_transform(kg, object, OBJECT_INVERSE_TRANSFORM);
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*P = transform_point(&tfm, ray->P);
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float3 dir = transform_direction(&tfm, ray->D);
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float len;
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dir = normalize_len(dir, &len);
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*idir = bvh_inverse_direction(dir);
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if(*t != FLT_MAX)
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*t *= len;
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}
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__device_inline void bvh_instance_pop(KernelGlobals *kg, int object, const Ray *ray, float3 *P, float3 *idir, float *t, const float tmax)
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{
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if(*t != FLT_MAX) {
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Transform tfm = object_fetch_transform(kg, object, OBJECT_TRANSFORM);
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*t *= len(transform_direction(&tfm, 1.0f/(*idir)));
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}
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*P = ray->P;
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*idir = bvh_inverse_direction(ray->D);
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}
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#ifdef __OBJECT_MOTION__
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__device_inline void bvh_instance_motion_push(KernelGlobals *kg, int object, const Ray *ray, float3 *P, float3 *idir, float *t, Transform *tfm, const float tmax)
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{
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Transform itfm;
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*tfm = object_fetch_transform_motion_test(kg, object, ray->time, &itfm);
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*P = transform_point(&itfm, ray->P);
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float3 dir = transform_direction(&itfm, ray->D);
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float len;
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dir = normalize_len(dir, &len);
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*idir = bvh_inverse_direction(dir);
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if(*t != FLT_MAX)
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*t *= len;
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}
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__device_inline void bvh_instance_motion_pop(KernelGlobals *kg, int object, const Ray *ray, float3 *P, float3 *idir, float *t, Transform *tfm, const float tmax)
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{
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if(*t != FLT_MAX)
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*t *= len(transform_direction(tfm, 1.0f/(*idir)));
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*P = ray->P;
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*idir = bvh_inverse_direction(ray->D);
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}
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#endif
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/* intersect two bounding boxes */
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__device_inline void bvh_node_intersect(KernelGlobals *kg,
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bool *traverseChild0, bool *traverseChild1,
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bool *closestChild1, int *nodeAddr0, int *nodeAddr1,
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float3 P, float3 idir, float t, uint visibility, int nodeAddr)
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{
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/* fetch node data */
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float4 n0xy = kernel_tex_fetch(__bvh_nodes, nodeAddr*BVH_NODE_SIZE+0);
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float4 n1xy = kernel_tex_fetch(__bvh_nodes, nodeAddr*BVH_NODE_SIZE+1);
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float4 nz = kernel_tex_fetch(__bvh_nodes, nodeAddr*BVH_NODE_SIZE+2);
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float4 cnodes = kernel_tex_fetch(__bvh_nodes, nodeAddr*BVH_NODE_SIZE+3);
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/* intersect ray against child nodes */
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float3 ood = P * idir;
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NO_EXTENDED_PRECISION float c0lox = n0xy.x * idir.x - ood.x;
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NO_EXTENDED_PRECISION float c0hix = n0xy.y * idir.x - ood.x;
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NO_EXTENDED_PRECISION float c0loy = n0xy.z * idir.y - ood.y;
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NO_EXTENDED_PRECISION float c0hiy = n0xy.w * idir.y - ood.y;
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NO_EXTENDED_PRECISION float c0loz = nz.x * idir.z - ood.z;
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NO_EXTENDED_PRECISION float c0hiz = nz.y * idir.z - ood.z;
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NO_EXTENDED_PRECISION float c0min = max4(min(c0lox, c0hix), min(c0loy, c0hiy), min(c0loz, c0hiz), 0.0f);
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NO_EXTENDED_PRECISION float c0max = min4(max(c0lox, c0hix), max(c0loy, c0hiy), max(c0loz, c0hiz), t);
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NO_EXTENDED_PRECISION float c1loz = nz.z * idir.z - ood.z;
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NO_EXTENDED_PRECISION float c1hiz = nz.w * idir.z - ood.z;
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NO_EXTENDED_PRECISION float c1lox = n1xy.x * idir.x - ood.x;
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NO_EXTENDED_PRECISION float c1hix = n1xy.y * idir.x - ood.x;
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NO_EXTENDED_PRECISION float c1loy = n1xy.z * idir.y - ood.y;
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NO_EXTENDED_PRECISION float c1hiy = n1xy.w * idir.y - ood.y;
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NO_EXTENDED_PRECISION float c1min = max4(min(c1lox, c1hix), min(c1loy, c1hiy), min(c1loz, c1hiz), 0.0f);
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NO_EXTENDED_PRECISION float c1max = min4(max(c1lox, c1hix), max(c1loy, c1hiy), max(c1loz, c1hiz), t);
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/* decide which nodes to traverse next */
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#ifdef __VISIBILITY_FLAG__
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/* this visibility test gives a 5% performance hit, how to solve? */
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*traverseChild0 = (c0max >= c0min) && (__float_as_int(cnodes.z) & visibility);
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*traverseChild1 = (c1max >= c1min) && (__float_as_int(cnodes.w) & visibility);
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#else
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*traverseChild0 = (c0max >= c0min);
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*traverseChild1 = (c1max >= c1min);
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#endif
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*nodeAddr0 = __float_as_int(cnodes.x);
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*nodeAddr1 = __float_as_int(cnodes.y);
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*closestChild1 = (c1min < c0min);
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}
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/* Sven Woop's algorithm */
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__device_inline void bvh_triangle_intersect(KernelGlobals *kg, Intersection *isect,
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float3 P, float3 idir, uint visibility, int object, int triAddr)
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{
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/* compute and check intersection t-value */
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float4 v00 = kernel_tex_fetch(__tri_woop, triAddr*TRI_NODE_SIZE+0);
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float4 v11 = kernel_tex_fetch(__tri_woop, triAddr*TRI_NODE_SIZE+1);
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float3 dir = 1.0f/idir;
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float Oz = v00.w - P.x*v00.x - P.y*v00.y - P.z*v00.z;
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float invDz = 1.0f/(dir.x*v00.x + dir.y*v00.y + dir.z*v00.z);
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float t = Oz * invDz;
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if(t > 0.0f && t < isect->t) {
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/* compute and check barycentric u */
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float Ox = v11.w + P.x*v11.x + P.y*v11.y + P.z*v11.z;
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float Dx = dir.x*v11.x + dir.y*v11.y + dir.z*v11.z;
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float u = Ox + t*Dx;
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if(u >= 0.0f) {
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/* compute and check barycentric v */
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float4 v22 = kernel_tex_fetch(__tri_woop, triAddr*TRI_NODE_SIZE+2);
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float Oy = v22.w + P.x*v22.x + P.y*v22.y + P.z*v22.z;
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float Dy = dir.x*v22.x + dir.y*v22.y + dir.z*v22.z;
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float v = Oy + t*Dy;
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if(v >= 0.0f && u + v <= 1.0f) {
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#ifdef __VISIBILITY_FLAG__
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/* visibility flag test. we do it here under the assumption
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* that most triangles are culled by node flags */
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if(kernel_tex_fetch(__prim_visibility, triAddr) & visibility)
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#endif
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{
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/* record intersection */
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isect->prim = triAddr;
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isect->object = object;
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isect->u = u;
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isect->v = v;
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isect->t = t;
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}
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}
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}
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}
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}
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#ifdef __HAIR__
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__device_inline void curvebounds(float *lower, float *upper, float *extremta, float *extrema, float *extremtb, float *extremb, float p0, float p1, float p2, float p3)
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{
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float halfdiscroot = (p2 * p2 - 3 * p3 * p1);
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float ta = -1.0f;
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float tb = -1.0f;
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*extremta = -1.0f;
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*extremtb = -1.0f;
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*upper = p0;
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*lower = p0 + p1 + p2 + p3;
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*extrema = *upper;
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*extremb = *lower;
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if(*lower >= *upper) {
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*upper = *lower;
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*lower = p0;
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}
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if(halfdiscroot >= 0) {
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halfdiscroot = sqrt(halfdiscroot);
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ta = (-p2 - halfdiscroot) / (3 * p3);
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tb = (-p2 + halfdiscroot) / (3 * p3);
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}
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float t2;
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float t3;
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if(ta > 0.0f && ta < 1.0f) {
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t2 = ta * ta;
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t3 = t2 * ta;
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*extremta = ta;
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*extrema = p3 * t3 + p2 * t2 + p1 * ta + p0;
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if(*extrema > *upper) {
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*upper = *extrema;
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}
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if(*extrema < *lower) {
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*lower = *extrema;
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}
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}
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if(tb > 0.0f && tb < 1.0f) {
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t2 = tb * tb;
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t3 = t2 * tb;
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*extremtb = tb;
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*extremb = p3 * t3 + p2 * t2 + p1 * tb + p0;
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if(*extremb >= *upper) {
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*upper = *extremb;
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}
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if(*extremb <= *lower) {
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*lower = *extremb;
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}
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}
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}
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__device_inline void bvh_cardinal_curve_intersect(KernelGlobals *kg, Intersection *isect,
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float3 P, float3 idir, uint visibility, int object, int curveAddr, int segment)
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{
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int depth = kernel_data.curve_kernel_data.subdivisions;
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/* curve Intersection check */
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float3 dir = 1.0f/idir;
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int flags = kernel_data.curve_kernel_data.curveflags;
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int prim = kernel_tex_fetch(__prim_index, curveAddr);
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float3 curve_coef[4];
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float r_st,r_en;
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/*obtain curve parameters*/
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{
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/*ray transform created - this shold be created at beginning of intersection loop*/
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Transform htfm;
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float d = sqrtf(dir.x * dir.x + dir.z * dir.z);
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htfm = make_transform(
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dir.z / d, 0, -dir.x /d, 0,
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-dir.x * dir.y /d, d, -dir.y * dir.z /d, 0,
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dir.x, dir.y, dir.z, 0,
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0, 0, 0, 1) * make_transform(
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1, 0, 0, -P.x,
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0, 1, 0, -P.y,
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0, 0, 1, -P.z,
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0, 0, 0, 1);
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float4 v00 = kernel_tex_fetch(__curves, prim);
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int k0 = __float_as_int(v00.x) + segment;
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int k1 = k0 + 1;
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int ka = max(k0 - 1,__float_as_int(v00.x));
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int kb = min(k1 + 1,__float_as_int(v00.x) + __float_as_int(v00.y) - 1);
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float4 P0 = kernel_tex_fetch(__curve_keys, ka);
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float4 P1 = kernel_tex_fetch(__curve_keys, k0);
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float4 P2 = kernel_tex_fetch(__curve_keys, k1);
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float4 P3 = kernel_tex_fetch(__curve_keys, kb);
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float3 p0 = transform_point(&htfm, float4_to_float3(P0));
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float3 p1 = transform_point(&htfm, float4_to_float3(P1));
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float3 p2 = transform_point(&htfm, float4_to_float3(P2));
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float3 p3 = transform_point(&htfm, float4_to_float3(P3));
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float fc = 0.71f;
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curve_coef[0] = p1;
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curve_coef[1] = -fc*p0 + fc*p2;
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curve_coef[2] = 2.0f * fc * p0 + (fc - 3.0f) * p1 + (3.0f - 2.0f * fc) * p2 - fc * p3;
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curve_coef[3] = -fc * p0 + (2.0f - fc) * p1 + (fc - 2.0f) * p2 + fc * p3;
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r_st = P1.w;
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r_en = P2.w;
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}
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float r_curr = max(r_st, r_en);
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/*find bounds - this is slow for cubic curves*/
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float upper,lower;
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float xextrem[4];
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curvebounds(&lower, &upper, &xextrem[0], &xextrem[1], &xextrem[2], &xextrem[3], curve_coef[0].x, curve_coef[1].x, curve_coef[2].x, curve_coef[3].x);
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if(lower > r_curr || upper < -r_curr)
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return;
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float yextrem[4];
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curvebounds(&lower, &upper, &yextrem[0], &yextrem[1], &yextrem[2], &yextrem[3], curve_coef[0].y, curve_coef[1].y, curve_coef[2].y, curve_coef[3].y);
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if(lower > r_curr || upper < -r_curr)
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return;
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float zextrem[4];
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curvebounds(&lower, &upper, &zextrem[0], &zextrem[1], &zextrem[2], &zextrem[3], curve_coef[0].z, curve_coef[1].z, curve_coef[2].z, curve_coef[3].z);
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if(lower - r_curr > isect->t || upper + r_curr < 0.0f)
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return;
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/*setup recurrent loop*/
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int level = 1 << depth;
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int tree = 0;
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float resol = 1.0f / (float)level;
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/*begin loop*/
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while(!(tree >> (depth))) {
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float i_st = tree * resol;
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float i_en = i_st + (level * resol);
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float3 p_st = ((curve_coef[3] * i_st + curve_coef[2]) * i_st + curve_coef[1]) * i_st + curve_coef[0];
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float3 p_en = ((curve_coef[3] * i_en + curve_coef[2]) * i_en + curve_coef[1]) * i_en + curve_coef[0];
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float bminx = min(p_st.x, p_en.x);
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float bmaxx = max(p_st.x, p_en.x);
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float bminy = min(p_st.y, p_en.y);
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float bmaxy = max(p_st.y, p_en.y);
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float bminz = min(p_st.z, p_en.z);
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float bmaxz = max(p_st.z, p_en.z);
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if(xextrem[0] >= i_st && xextrem[0] <= i_en) {
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bminx = min(bminx,xextrem[1]);
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bmaxx = max(bmaxx,xextrem[1]);
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}
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if(xextrem[2] >= i_st && xextrem[2] <= i_en) {
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bminx = min(bminx,xextrem[3]);
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bmaxx = max(bmaxx,xextrem[3]);
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}
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if(yextrem[0] >= i_st && yextrem[0] <= i_en) {
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bminy = min(bminy,yextrem[1]);
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bmaxy = max(bmaxy,yextrem[1]);
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}
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if(yextrem[2] >= i_st && yextrem[2] <= i_en) {
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bminy = min(bminy,yextrem[3]);
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bmaxy = max(bmaxy,yextrem[3]);
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}
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if(zextrem[0] >= i_st && zextrem[0] <= i_en) {
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bminz = min(bminz,zextrem[1]);
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bmaxz = max(bmaxz,zextrem[1]);
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}
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if(zextrem[2] >= i_st && zextrem[2] <= i_en) {
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bminz = min(bminz,zextrem[3]);
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bmaxz = max(bmaxz,zextrem[3]);
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}
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float r1 = r_st + (r_en - r_st) * i_st;
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float r2 = r_st + (r_en - r_st) * i_en;
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r_curr = max(r1, r2);
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if (bminz - r_curr > isect->t || bmaxz + r_curr < 0.0f|| bminx > r_curr || bmaxx < -r_curr || bminy > r_curr || bmaxy < -r_curr) {
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/* the bounding box does not overlap the square centered at O.*/
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tree += level;
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level = tree & -tree;
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}
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else if (level == 1) {
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/* the maximum recursion depth is reached.
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* check if dP0.(Q-P0)>=0 and dPn.(Pn-Q)>=0.
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* dP* is reversed if necessary.*/
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float t = isect->t;
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float u = 0.0f;
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if(flags & CURVE_KN_RIBBONS) {
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float3 tg = (p_en - p_st);
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float w = tg.x * tg.x + tg.y * tg.y;
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if (w == 0) {
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|
tree++;
|
|
level = tree & -tree;
|
|
continue;
|
|
}
|
|
w = -(p_st.x * tg.x + p_st.y * tg.y) / w;
|
|
w = clamp((float)w, 0.0f, 1.0f);
|
|
|
|
/* compute u on the curve segment.*/
|
|
u = i_st * (1 - w) + i_en * w;
|
|
r_curr = r_st + (r_en - r_st) * u;
|
|
/* compare x-y distances.*/
|
|
float3 p_curr = ((curve_coef[3] * u + curve_coef[2]) * u + curve_coef[1]) * u + curve_coef[0];
|
|
|
|
float3 dp_st = (3 * curve_coef[3] * i_st + 2 * curve_coef[2]) * i_st + curve_coef[1];
|
|
if (dot(tg, dp_st)< 0)
|
|
dp_st *= -1;
|
|
if (dot(dp_st, -p_st) + p_curr.z * dp_st.z < 0) {
|
|
tree++;
|
|
level = tree & -tree;
|
|
continue;
|
|
}
|
|
float3 dp_en = (3 * curve_coef[3] * i_en + 2 * curve_coef[2]) * i_en + curve_coef[1];
|
|
if (dot(tg, dp_en) < 0)
|
|
dp_en *= -1;
|
|
if (dot(dp_en, p_en) - p_curr.z * dp_en.z < 0) {
|
|
tree++;
|
|
level = tree & -tree;
|
|
continue;
|
|
}
|
|
|
|
if (p_curr.x * p_curr.x + p_curr.y * p_curr.y >= r_curr * r_curr || p_curr.z <= 0.0f) {
|
|
tree++;
|
|
level = tree & -tree;
|
|
continue;
|
|
}
|
|
/* compare z distances.*/
|
|
if (isect->t < p_curr.z) {
|
|
tree++;
|
|
level = tree & -tree;
|
|
continue;
|
|
}
|
|
t = p_curr.z;
|
|
}
|
|
else {
|
|
float l = len(p_en - p_st);
|
|
float3 tg = (p_en - p_st) / l;
|
|
float gd = (r2 - r1) / l;
|
|
float difz = -dot(p_st,tg);
|
|
float cyla = 1.0f - (tg.z * tg.z * (1 + gd*gd));
|
|
float halfb = (-p_st.z - tg.z*(difz + gd*(difz*gd + r1)));
|
|
float tcentre = -halfb/cyla;
|
|
float zcentre = difz + (tg.z * tcentre);
|
|
float3 tdif = - p_st;
|
|
tdif.z += tcentre;
|
|
float tdifz = dot(tdif,tg);
|
|
float tb = 2*(tdif.z - tg.z*(tdifz + gd*(tdifz*gd + r1)));
|
|
float tc = dot(tdif,tdif) - tdifz * tdifz * (1 + gd*gd) - r1*r1 - 2*r1*tdifz*gd;
|
|
float td = tb*tb - 4*cyla*tc;
|
|
if (td < 0.0f){
|
|
tree++;
|
|
level = tree & -tree;
|
|
continue;
|
|
}
|
|
|
|
float rootd = sqrtf(td);
|
|
float correction = ((-tb - rootd)/(2*cyla));
|
|
t = tcentre + correction;
|
|
float w = (zcentre + (tg.z * correction))/l;
|
|
|
|
float3 dp_st = (3 * curve_coef[3] * i_st + 2 * curve_coef[2]) * i_st + curve_coef[1];
|
|
if (dot(tg, dp_st)< 0)
|
|
dp_st *= -1;
|
|
float3 dp_en = (3 * curve_coef[3] * i_en + 2 * curve_coef[2]) * i_en + curve_coef[1];
|
|
if (dot(tg, dp_en) < 0)
|
|
dp_en *= -1;
|
|
|
|
|
|
if(flags & CURVE_KN_BACKFACING && (dot(dp_st, -p_st) + t * dp_st.z < 0 || dot(dp_en, p_en) - t * dp_en.z < 0 || isect->t < t || t <= 0.0f)) {
|
|
correction = ((-tb + rootd)/(2*cyla));
|
|
t = tcentre + correction;
|
|
w = (zcentre + (tg.z * correction))/l;
|
|
}
|
|
|
|
if (dot(dp_st, -p_st) + t * dp_st.z < 0 || dot(dp_en, p_en) - t * dp_en.z < 0 || isect->t < t || t <= 0.0f) {
|
|
tree++;
|
|
level = tree & -tree;
|
|
continue;
|
|
}
|
|
|
|
w = clamp((float)w, 0.0f, 1.0f);
|
|
/* compute u on the curve segment.*/
|
|
u = i_st * (1 - w) + i_en * w;
|
|
|
|
}
|
|
/* we found a new intersection.*/
|
|
#ifdef __VISIBILITY_FLAG__
|
|
/* visibility flag test. we do it here under the assumption
|
|
* that most triangles are culled by node flags */
|
|
if(kernel_tex_fetch(__prim_visibility, curveAddr) & visibility)
|
|
#endif
|
|
{
|
|
/* record intersection */
|
|
isect->prim = curveAddr;
|
|
isect->segment = segment;
|
|
isect->object = object;
|
|
isect->u = u;
|
|
isect->v = 0.0f;
|
|
isect->t = t;
|
|
}
|
|
|
|
tree++;
|
|
level = tree & -tree;
|
|
}
|
|
else {
|
|
/* split the curve into two curves and process */
|
|
level = level >> 1;
|
|
}
|
|
}
|
|
}
|
|
|
|
__device_inline void bvh_curve_intersect(KernelGlobals *kg, Intersection *isect,
|
|
float3 P, float3 idir, uint visibility, int object, int curveAddr, int segment)
|
|
{
|
|
/* curve Intersection check */
|
|
|
|
int flags = kernel_data.curve_kernel_data.curveflags;
|
|
|
|
int prim = kernel_tex_fetch(__prim_index, curveAddr);
|
|
float4 v00 = kernel_tex_fetch(__curves, prim);
|
|
|
|
int k0 = __float_as_int(v00.x) + segment;
|
|
int k1 = k0 + 1;
|
|
|
|
float4 P1 = kernel_tex_fetch(__curve_keys, k0);
|
|
float4 P2 = kernel_tex_fetch(__curve_keys, k1);
|
|
|
|
float r1 = P1.w;
|
|
float r2 = P2.w;
|
|
float mr = max(r1,r2);
|
|
float3 p1 = float4_to_float3(P1);
|
|
float3 p2 = float4_to_float3(P2);
|
|
float3 dif = P - p1;
|
|
float3 dir = 1.0f/idir;
|
|
float l = len(p2 - p1);
|
|
|
|
float sp_r = mr + 0.5f * l;
|
|
float3 sphere_dif = P - ((p1 + p2) * 0.5f);
|
|
float sphere_b = dot(dir,sphere_dif);
|
|
sphere_dif = sphere_dif - sphere_b * dir;
|
|
sphere_b = dot(dir,sphere_dif);
|
|
float sdisc = sphere_b * sphere_b - len_squared(sphere_dif) + sp_r * sp_r;
|
|
if(sdisc < 0.0f)
|
|
return;
|
|
|
|
/* obtain parameters and test midpoint distance for suitable modes*/
|
|
float3 tg = (p2 - p1) / l;
|
|
float gd = (r2 - r1) / l;
|
|
float dirz = dot(dir,tg);
|
|
float difz = dot(dif,tg);
|
|
|
|
float a = 1.0f - (dirz*dirz*(1 + gd*gd));
|
|
float halfb = (dot(dir,dif) - dirz*(difz + gd*(difz*gd + r1)));
|
|
|
|
float tcentre = -halfb/a;
|
|
float zcentre = difz + (dirz * tcentre);
|
|
|
|
if((tcentre > isect->t) && !(flags & CURVE_KN_ACCURATE))
|
|
return;
|
|
if((zcentre < 0 || zcentre > l) && !(flags & CURVE_KN_ACCURATE) && !(flags & CURVE_KN_INTERSECTCORRECTION))
|
|
return;
|
|
|
|
/* test minimum separation*/
|
|
float3 cprod = cross(tg, dir);
|
|
float3 cprod2 = cross(tg, dif);
|
|
float cprodsq = len_squared(cprod);
|
|
float cprod2sq = len_squared(cprod2);
|
|
float distscaled = dot(cprod,dif);
|
|
|
|
if(cprodsq == 0)
|
|
distscaled = cprod2sq;
|
|
else
|
|
distscaled = (distscaled*distscaled)/cprodsq;
|
|
|
|
if(distscaled > mr*mr)
|
|
return;
|
|
|
|
/* calculate true intersection*/
|
|
float3 tdif = P - p1 + tcentre * dir;
|
|
float tdifz = dot(tdif,tg);
|
|
float tb = 2*(dot(dir,tdif) - dirz*(tdifz + gd*(tdifz*gd + r1)));
|
|
float tc = dot(tdif,tdif) - tdifz * tdifz * (1 + gd*gd) - r1*r1 - 2*r1*tdifz*gd;
|
|
float td = tb*tb - 4*a*tc;
|
|
|
|
if (td < 0.0f)
|
|
return;
|
|
|
|
float rootd = 0.0f;
|
|
float correction = 0.0f;
|
|
if(flags & CURVE_KN_ACCURATE) {
|
|
rootd = sqrtf(td);
|
|
correction = ((-tb - rootd)/(2*a));
|
|
}
|
|
|
|
float t = tcentre + correction;
|
|
|
|
if(t < isect->t) {
|
|
|
|
if(flags & CURVE_KN_INTERSECTCORRECTION) {
|
|
rootd = sqrtf(td);
|
|
correction = ((-tb - rootd)/(2*a));
|
|
t = tcentre + correction;
|
|
}
|
|
|
|
float z = zcentre + (dirz * correction);
|
|
bool backface = false;
|
|
|
|
if(flags & CURVE_KN_BACKFACING && (t < 0.0f || z < 0 || z > l)) {
|
|
backface = true;
|
|
correction = ((-tb + rootd)/(2*a));
|
|
t = tcentre + correction;
|
|
z = zcentre + (dirz * correction);
|
|
}
|
|
|
|
if(t > 0.0f && t < isect->t && z >= 0 && z <= l) {
|
|
|
|
if (flags & CURVE_KN_ENCLOSEFILTER) {
|
|
|
|
float enc_ratio = kernel_data.curve_kernel_data.encasing_ratio;
|
|
if((dot(P - p1, tg) > -r1 * enc_ratio) && (dot(P - p2, tg) < r2 * enc_ratio)) {
|
|
float a2 = 1.0f - (dirz*dirz*(1 + gd*gd*enc_ratio*enc_ratio));
|
|
float c2 = dot(dif,dif) - difz * difz * (1 + gd*gd*enc_ratio*enc_ratio) - r1*r1*enc_ratio*enc_ratio - 2*r1*difz*gd*enc_ratio;
|
|
if(a2*c2 < 0.0f)
|
|
return;
|
|
}
|
|
}
|
|
|
|
#ifdef __VISIBILITY_FLAG__
|
|
/* visibility flag test. we do it here under the assumption
|
|
* that most triangles are culled by node flags */
|
|
if(kernel_tex_fetch(__prim_visibility, curveAddr) & visibility)
|
|
#endif
|
|
{
|
|
/* record intersection */
|
|
isect->prim = curveAddr;
|
|
isect->segment = segment;
|
|
isect->object = object;
|
|
isect->u = z/l;
|
|
isect->v = td/(4*a*a);
|
|
isect->t = t;
|
|
|
|
if(backface)
|
|
isect->u = -isect->u;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
#endif
|
|
|
|
__device bool bvh_intersect(KernelGlobals *kg, const Ray *ray, const uint visibility, Intersection *isect)
|
|
{
|
|
/* traversal stack in CUDA thread-local memory */
|
|
int traversalStack[BVH_STACK_SIZE];
|
|
traversalStack[0] = ENTRYPOINT_SENTINEL;
|
|
|
|
/* traversal variables in registers */
|
|
int stackPtr = 0;
|
|
int nodeAddr = kernel_data.bvh.root;
|
|
|
|
/* ray parameters in registers */
|
|
const float tmax = ray->t;
|
|
float3 P = ray->P;
|
|
float3 idir = bvh_inverse_direction(ray->D);
|
|
int object = ~0;
|
|
|
|
isect->t = tmax;
|
|
isect->object = ~0;
|
|
isect->prim = ~0;
|
|
isect->u = 0.0f;
|
|
isect->v = 0.0f;
|
|
|
|
/* traversal loop */
|
|
do {
|
|
do
|
|
{
|
|
/* traverse internal nodes */
|
|
while(nodeAddr >= 0 && nodeAddr != ENTRYPOINT_SENTINEL)
|
|
{
|
|
bool traverseChild0, traverseChild1, closestChild1;
|
|
int nodeAddrChild1;
|
|
|
|
bvh_node_intersect(kg, &traverseChild0, &traverseChild1,
|
|
&closestChild1, &nodeAddr, &nodeAddrChild1,
|
|
P, idir, isect->t, visibility, nodeAddr);
|
|
|
|
if(traverseChild0 != traverseChild1) {
|
|
/* one child was intersected */
|
|
if(traverseChild1) {
|
|
nodeAddr = nodeAddrChild1;
|
|
}
|
|
}
|
|
else {
|
|
if(!traverseChild0) {
|
|
/* neither child was intersected */
|
|
nodeAddr = traversalStack[stackPtr];
|
|
--stackPtr;
|
|
}
|
|
else {
|
|
/* both children were intersected, push the farther one */
|
|
if(closestChild1) {
|
|
int tmp = nodeAddr;
|
|
nodeAddr = nodeAddrChild1;
|
|
nodeAddrChild1 = tmp;
|
|
}
|
|
|
|
++stackPtr;
|
|
traversalStack[stackPtr] = nodeAddrChild1;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* if node is leaf, fetch triangle list */
|
|
if(nodeAddr < 0) {
|
|
float4 leaf = kernel_tex_fetch(__bvh_nodes, (-nodeAddr-1)*BVH_NODE_SIZE+(BVH_NODE_SIZE-1));
|
|
int primAddr = __float_as_int(leaf.x);
|
|
|
|
#ifdef __INSTANCING__
|
|
if(primAddr >= 0) {
|
|
#endif
|
|
int primAddr2 = __float_as_int(leaf.y);
|
|
|
|
/* pop */
|
|
nodeAddr = traversalStack[stackPtr];
|
|
--stackPtr;
|
|
|
|
/* primitive intersection */
|
|
while(primAddr < primAddr2) {
|
|
/* intersect ray against primitive */
|
|
#ifdef __HAIR__
|
|
uint segment = kernel_tex_fetch(__prim_segment, primAddr);
|
|
if(segment != ~0) {
|
|
if(kernel_data.curve_kernel_data.curveflags & CURVE_KN_INTERPOLATE)
|
|
bvh_cardinal_curve_intersect(kg, isect, P, idir, visibility, object, primAddr, segment);
|
|
else
|
|
bvh_curve_intersect(kg, isect, P, idir, visibility, object, primAddr, segment);
|
|
}
|
|
else
|
|
#endif
|
|
bvh_triangle_intersect(kg, isect, P, idir, visibility, object, primAddr);
|
|
|
|
/* shadow ray early termination */
|
|
if(visibility == PATH_RAY_SHADOW_OPAQUE && isect->prim != ~0)
|
|
return true;
|
|
|
|
primAddr++;
|
|
}
|
|
#ifdef __INSTANCING__
|
|
}
|
|
else {
|
|
/* instance push */
|
|
object = kernel_tex_fetch(__prim_object, -primAddr-1);
|
|
bvh_instance_push(kg, object, ray, &P, &idir, &isect->t, tmax);
|
|
|
|
++stackPtr;
|
|
traversalStack[stackPtr] = ENTRYPOINT_SENTINEL;
|
|
|
|
nodeAddr = kernel_tex_fetch(__object_node, object);
|
|
}
|
|
#endif
|
|
}
|
|
} while(nodeAddr != ENTRYPOINT_SENTINEL);
|
|
|
|
#ifdef __INSTANCING__
|
|
if(stackPtr >= 0) {
|
|
kernel_assert(object != ~0);
|
|
|
|
/* instance pop */
|
|
bvh_instance_pop(kg, object, ray, &P, &idir, &isect->t, tmax);
|
|
object = ~0;
|
|
nodeAddr = traversalStack[stackPtr];
|
|
--stackPtr;
|
|
}
|
|
#endif
|
|
} while(nodeAddr != ENTRYPOINT_SENTINEL);
|
|
|
|
return (isect->prim != ~0);
|
|
}
|
|
|
|
#ifdef __OBJECT_MOTION__
|
|
__device bool bvh_intersect_motion(KernelGlobals *kg, const Ray *ray, const uint visibility, Intersection *isect)
|
|
{
|
|
/* traversal stack in CUDA thread-local memory */
|
|
int traversalStack[BVH_STACK_SIZE];
|
|
traversalStack[0] = ENTRYPOINT_SENTINEL;
|
|
|
|
/* traversal variables in registers */
|
|
int stackPtr = 0;
|
|
int nodeAddr = kernel_data.bvh.root;
|
|
|
|
/* ray parameters in registers */
|
|
const float tmax = ray->t;
|
|
float3 P = ray->P;
|
|
float3 idir = bvh_inverse_direction(ray->D);
|
|
int object = ~0;
|
|
|
|
Transform ob_tfm;
|
|
|
|
isect->t = tmax;
|
|
isect->object = ~0;
|
|
isect->prim = ~0;
|
|
isect->u = 0.0f;
|
|
isect->v = 0.0f;
|
|
|
|
/* traversal loop */
|
|
do {
|
|
do
|
|
{
|
|
/* traverse internal nodes */
|
|
while(nodeAddr >= 0 && nodeAddr != ENTRYPOINT_SENTINEL)
|
|
{
|
|
bool traverseChild0, traverseChild1, closestChild1;
|
|
int nodeAddrChild1;
|
|
|
|
bvh_node_intersect(kg, &traverseChild0, &traverseChild1,
|
|
&closestChild1, &nodeAddr, &nodeAddrChild1,
|
|
P, idir, isect->t, visibility, nodeAddr);
|
|
|
|
if(traverseChild0 != traverseChild1) {
|
|
/* one child was intersected */
|
|
if(traverseChild1) {
|
|
nodeAddr = nodeAddrChild1;
|
|
}
|
|
}
|
|
else {
|
|
if(!traverseChild0) {
|
|
/* neither child was intersected */
|
|
nodeAddr = traversalStack[stackPtr];
|
|
--stackPtr;
|
|
}
|
|
else {
|
|
/* both children were intersected, push the farther one */
|
|
if(closestChild1) {
|
|
int tmp = nodeAddr;
|
|
nodeAddr = nodeAddrChild1;
|
|
nodeAddrChild1 = tmp;
|
|
}
|
|
|
|
++stackPtr;
|
|
traversalStack[stackPtr] = nodeAddrChild1;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* if node is leaf, fetch triangle list */
|
|
if(nodeAddr < 0) {
|
|
float4 leaf = kernel_tex_fetch(__bvh_nodes, (-nodeAddr-1)*BVH_NODE_SIZE+(BVH_NODE_SIZE-1));
|
|
int primAddr = __float_as_int(leaf.x);
|
|
|
|
if(primAddr >= 0) {
|
|
int primAddr2 = __float_as_int(leaf.y);
|
|
|
|
/* pop */
|
|
nodeAddr = traversalStack[stackPtr];
|
|
--stackPtr;
|
|
|
|
/* primitive intersection */
|
|
while(primAddr < primAddr2) {
|
|
/* intersect ray against primitive */
|
|
#ifdef __HAIR__
|
|
uint segment = kernel_tex_fetch(__prim_segment, primAddr);
|
|
if(segment != ~0) {
|
|
if(kernel_data.curve_kernel_data.curveflags & CURVE_KN_INTERPOLATE)
|
|
bvh_cardinal_curve_intersect(kg, isect, P, idir, visibility, object, primAddr, segment);
|
|
else
|
|
bvh_curve_intersect(kg, isect, P, idir, visibility, object, primAddr, segment);
|
|
}
|
|
else
|
|
#endif
|
|
bvh_triangle_intersect(kg, isect, P, idir, visibility, object, primAddr);
|
|
|
|
/* shadow ray early termination */
|
|
if(visibility == PATH_RAY_SHADOW_OPAQUE && isect->prim != ~0)
|
|
return true;
|
|
|
|
primAddr++;
|
|
}
|
|
}
|
|
else {
|
|
/* instance push */
|
|
object = kernel_tex_fetch(__prim_object, -primAddr-1);
|
|
bvh_instance_motion_push(kg, object, ray, &P, &idir, &isect->t, &ob_tfm, tmax);
|
|
|
|
++stackPtr;
|
|
traversalStack[stackPtr] = ENTRYPOINT_SENTINEL;
|
|
|
|
nodeAddr = kernel_tex_fetch(__object_node, object);
|
|
}
|
|
}
|
|
} while(nodeAddr != ENTRYPOINT_SENTINEL);
|
|
|
|
if(stackPtr >= 0) {
|
|
kernel_assert(object != ~0);
|
|
|
|
/* instance pop */
|
|
bvh_instance_motion_pop(kg, object, ray, &P, &idir, &isect->t, &ob_tfm, tmax);
|
|
object = ~0;
|
|
nodeAddr = traversalStack[stackPtr];
|
|
--stackPtr;
|
|
}
|
|
} while(nodeAddr != ENTRYPOINT_SENTINEL);
|
|
|
|
return (isect->prim != ~0);
|
|
}
|
|
#endif
|
|
|
|
__device_inline bool scene_intersect(KernelGlobals *kg, const Ray *ray, const uint visibility, Intersection *isect)
|
|
{
|
|
#ifdef __OBJECT_MOTION__
|
|
if(kernel_data.bvh.have_motion)
|
|
return bvh_intersect_motion(kg, ray, visibility, isect);
|
|
else
|
|
return bvh_intersect(kg, ray, visibility, isect);
|
|
#else
|
|
return bvh_intersect(kg, ray, visibility, isect);
|
|
#endif
|
|
}
|
|
|
|
__device_inline float3 ray_offset(float3 P, float3 Ng)
|
|
{
|
|
#ifdef __INTERSECTION_REFINE__
|
|
const float epsilon_f = 1e-5f;
|
|
/* ideally this should match epsilon_f, but instancing/mblur
|
|
* precision makes it problematic */
|
|
const float epsilon_test = 1.0f;
|
|
const int epsilon_i = 32;
|
|
|
|
float3 res;
|
|
|
|
/* x component */
|
|
if(fabsf(P.x) < epsilon_test) {
|
|
res.x = P.x + Ng.x*epsilon_f;
|
|
}
|
|
else {
|
|
uint ix = __float_as_uint(P.x);
|
|
ix += ((ix ^ __float_as_uint(Ng.x)) >> 31)? -epsilon_i: epsilon_i;
|
|
res.x = __uint_as_float(ix);
|
|
}
|
|
|
|
/* y component */
|
|
if(fabsf(P.y) < epsilon_test) {
|
|
res.y = P.y + Ng.y*epsilon_f;
|
|
}
|
|
else {
|
|
uint iy = __float_as_uint(P.y);
|
|
iy += ((iy ^ __float_as_uint(Ng.y)) >> 31)? -epsilon_i: epsilon_i;
|
|
res.y = __uint_as_float(iy);
|
|
}
|
|
|
|
/* z component */
|
|
if(fabsf(P.z) < epsilon_test) {
|
|
res.z = P.z + Ng.z*epsilon_f;
|
|
}
|
|
else {
|
|
uint iz = __float_as_uint(P.z);
|
|
iz += ((iz ^ __float_as_uint(Ng.z)) >> 31)? -epsilon_i: epsilon_i;
|
|
res.z = __uint_as_float(iz);
|
|
}
|
|
|
|
return res;
|
|
#else
|
|
const float epsilon_f = 1e-4f;
|
|
return P + epsilon_f*Ng;
|
|
#endif
|
|
}
|
|
|
|
__device_inline float3 bvh_triangle_refine(KernelGlobals *kg, ShaderData *sd, const Intersection *isect, const Ray *ray)
|
|
{
|
|
float3 P = ray->P;
|
|
float3 D = ray->D;
|
|
float t = isect->t;
|
|
|
|
#ifdef __INTERSECTION_REFINE__
|
|
if(isect->object != ~0) {
|
|
#ifdef __OBJECT_MOTION__
|
|
Transform tfm = sd->ob_itfm;
|
|
#else
|
|
Transform tfm = object_fetch_transform(kg, isect->object, OBJECT_INVERSE_TRANSFORM);
|
|
#endif
|
|
|
|
P = transform_point(&tfm, P);
|
|
D = transform_direction(&tfm, D*t);
|
|
D = normalize_len(D, &t);
|
|
}
|
|
|
|
P = P + D*t;
|
|
|
|
float4 v00 = kernel_tex_fetch(__tri_woop, isect->prim*TRI_NODE_SIZE+0);
|
|
float Oz = v00.w - P.x*v00.x - P.y*v00.y - P.z*v00.z;
|
|
float invDz = 1.0f/(D.x*v00.x + D.y*v00.y + D.z*v00.z);
|
|
float rt = Oz * invDz;
|
|
|
|
P = P + D*rt;
|
|
|
|
if(isect->object != ~0) {
|
|
#ifdef __OBJECT_MOTION__
|
|
Transform tfm = sd->ob_tfm;
|
|
#else
|
|
Transform tfm = object_fetch_transform(kg, isect->object, OBJECT_TRANSFORM);
|
|
#endif
|
|
|
|
P = transform_point(&tfm, P);
|
|
}
|
|
|
|
return P;
|
|
#else
|
|
return P + D*t;
|
|
#endif
|
|
}
|
|
|
|
#ifdef __HAIR__
|
|
|
|
__device_inline float3 curvetangent(float t, float3 p0, float3 p1, float3 p2, float3 p3)
|
|
{
|
|
float fc = 0.71f;
|
|
float data[4];
|
|
float t2 = t * t;
|
|
data[0] = -3.0f * fc * t2 + 4.0f * fc * t - fc;
|
|
data[1] = 3.0f * (2.0f - fc) * t2 + 2.0f * (fc - 3.0f) * t;
|
|
data[2] = 3.0f * (fc - 2.0f) * t2 + 2.0f * (3.0f - 2.0f * fc) * t + fc;
|
|
data[3] = 3.0f * fc * t2 - 2.0f * fc * t;
|
|
return data[0] * p0 + data[1] * p1 + data[2] * p2 + data[3] * p3;
|
|
}
|
|
|
|
__device_inline float3 curvepoint(float t, float3 p0, float3 p1, float3 p2, float3 p3)
|
|
{
|
|
float data[4];
|
|
float fc = 0.71f;
|
|
float t2 = t * t;
|
|
float t3 = t2 * t;
|
|
data[0] = -fc * t3 + 2.0f * fc * t2 - fc * t;
|
|
data[1] = (2.0f - fc) * t3 + (fc - 3.0f) * t2 + 1.0f;
|
|
data[2] = (fc - 2.0f) * t3 + (3.0f - 2.0f * fc) * t2 + fc * t;
|
|
data[3] = fc * t3 - fc * t2;
|
|
return data[0] * p0 + data[1] * p1 + data[2] * p2 + data[3] * p3;
|
|
}
|
|
|
|
__device_inline float3 bvh_curve_refine(KernelGlobals *kg, ShaderData *sd, const Intersection *isect, const Ray *ray, float t)
|
|
{
|
|
int flag = kernel_data.curve_kernel_data.curveflags;
|
|
float3 P = ray->P;
|
|
float3 D = ray->D;
|
|
|
|
if(isect->object != ~0) {
|
|
#ifdef __OBJECT_MOTION__
|
|
Transform tfm = sd->ob_itfm;
|
|
#else
|
|
Transform tfm = object_fetch_transform(kg, isect->object, OBJECT_INVERSE_TRANSFORM);
|
|
#endif
|
|
|
|
P = transform_point(&tfm, P);
|
|
D = transform_direction(&tfm, D*t);
|
|
D = normalize_len(D, &t);
|
|
}
|
|
|
|
int prim = kernel_tex_fetch(__prim_index, isect->prim);
|
|
float4 v00 = kernel_tex_fetch(__curves, prim);
|
|
|
|
int k0 = __float_as_int(v00.x) + isect->segment;
|
|
int k1 = k0 + 1;
|
|
|
|
float4 P1 = kernel_tex_fetch(__curve_keys, k0);
|
|
float4 P2 = kernel_tex_fetch(__curve_keys, k1);
|
|
float l = 1.0f;
|
|
float3 tg = normalize_len(float4_to_float3(P2 - P1),&l);
|
|
float r1 = P1.w;
|
|
float r2 = P2.w;
|
|
float gd = ((r2 - r1)/l);
|
|
|
|
P = P + D*t;
|
|
|
|
if(flag & CURVE_KN_INTERPOLATE) {
|
|
int ka = max(k0 - 1,__float_as_int(v00.x));
|
|
int kb = min(k1 + 1,__float_as_int(v00.x) + __float_as_int(v00.y) - 1);
|
|
|
|
float4 P0 = kernel_tex_fetch(__curve_keys, ka);
|
|
float4 P3 = kernel_tex_fetch(__curve_keys, kb);
|
|
|
|
float3 p[4];
|
|
p[0] = float4_to_float3(P0);
|
|
p[1] = float4_to_float3(P1);
|
|
p[2] = float4_to_float3(P2);
|
|
p[3] = float4_to_float3(P3);
|
|
|
|
tg = normalize(curvetangent(isect->u,p[0],p[1],p[2],p[3]));
|
|
float3 p_curr = curvepoint(isect->u,p[0],p[1],p[2],p[3]);
|
|
|
|
#ifdef __UV__
|
|
sd->u = isect->u;
|
|
sd->v = 0.0f;
|
|
#endif
|
|
|
|
if(kernel_data.curve_kernel_data.curveflags & CURVE_KN_RIBBONS)
|
|
sd->Ng = normalize(-(D - tg * (dot(tg,D))));
|
|
else {
|
|
sd->Ng = normalize(P - p_curr);
|
|
sd->Ng = sd->Ng - gd * tg;
|
|
sd->Ng = normalize(sd->Ng);
|
|
}
|
|
sd->N = sd->Ng;
|
|
}
|
|
else {
|
|
float3 dif = P - float4_to_float3(P1);
|
|
|
|
#ifdef __UV__
|
|
sd->u = dot(dif,tg)/l;
|
|
sd->v = 0.0f;
|
|
#endif
|
|
|
|
if (flag & CURVE_KN_TRUETANGENTGNORMAL) {
|
|
sd->Ng = -(D - tg * (dot(tg,D) * kernel_data.curve_kernel_data.normalmix));
|
|
sd->Ng = normalize(sd->Ng);
|
|
if (flag & CURVE_KN_NORMALCORRECTION) {
|
|
sd->Ng = sd->Ng - gd * tg;
|
|
sd->Ng = normalize(sd->Ng);
|
|
}
|
|
}
|
|
else {
|
|
sd->Ng = (dif - tg * sd->u * l) / (P1.w + sd->u * l * gd);
|
|
if (gd != 0.0f) {
|
|
sd->Ng = sd->Ng - gd * tg ;
|
|
sd->Ng = normalize(sd->Ng);
|
|
}
|
|
}
|
|
|
|
sd->N = sd->Ng;
|
|
|
|
if (flag & CURVE_KN_TANGENTGNORMAL && !(flag & CURVE_KN_TRUETANGENTGNORMAL)) {
|
|
sd->N = -(D - tg * (dot(tg,D) * kernel_data.curve_kernel_data.normalmix));
|
|
sd->N = normalize(sd->N);
|
|
if (flag & CURVE_KN_NORMALCORRECTION) {
|
|
sd->N = sd->N - gd * tg;
|
|
sd->N = normalize(sd->N);
|
|
}
|
|
}
|
|
if (!(flag & CURVE_KN_TANGENTGNORMAL) && flag & CURVE_KN_TRUETANGENTGNORMAL) {
|
|
sd->N = (dif - tg * sd->u * l) / (P1.w + sd->u * l * gd);
|
|
if (gd != 0.0f) {
|
|
sd->N = sd->N - gd * tg ;
|
|
sd->N = normalize(sd->N);
|
|
}
|
|
}
|
|
}
|
|
|
|
#ifdef __DPDU__
|
|
/* dPdu/dPdv */
|
|
sd->dPdu = tg;
|
|
sd->dPdv = cross(tg,sd->Ng);
|
|
#endif
|
|
|
|
if(isect->object != ~0) {
|
|
#ifdef __OBJECT_MOTION__
|
|
Transform tfm = sd->ob_tfm;
|
|
#else
|
|
Transform tfm = object_fetch_transform(kg, isect->object, OBJECT_TRANSFORM);
|
|
#endif
|
|
|
|
P = transform_point(&tfm, P);
|
|
}
|
|
|
|
return P;
|
|
}
|
|
#endif
|
|
|
|
CCL_NAMESPACE_END
|
|
|