forked from bartvdbraak/blender
dce16d57dc
The fix was really flacky, in terms during speed benchmarks i had abort() in the fallback block to be sure it never runs in production scenes, but that affected on the optimization as well. Without this abort there's quite bad slowdown of 5-7% on the renders even tho the Pleucker fallback was never run. This is all weird and for now reverting the change which affects on all the production scenes and will look into alternative fixes for the original issue with precision loss on huge planes. This reverts commit 9489205c5c0b9b432d02be4a3d0d15fc62ee6cb9.
424 lines
12 KiB
C
424 lines
12 KiB
C
/*
|
||
* Copyright 2014, Blender Foundation.
|
||
*
|
||
* Licensed under the Apache License, Version 2.0 (the "License");
|
||
* you may not use this file except in compliance with the License.
|
||
* You may obtain a copy of the License at
|
||
*
|
||
* http://www.apache.org/licenses/LICENSE-2.0
|
||
*
|
||
* Unless required by applicable law or agreed to in writing, software
|
||
* distributed under the License is distributed on an "AS IS" BASIS,
|
||
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||
* See the License for the specific language governing permissions and
|
||
* limitations under the License.
|
||
*/
|
||
|
||
/* Triangle/Ray intersections .
|
||
*
|
||
* For BVH ray intersection we use a precomputed triangle storage to accelerate
|
||
* intersection at the cost of more memory usage.
|
||
*/
|
||
|
||
CCL_NAMESPACE_BEGIN
|
||
|
||
/* Workaround stupidness of CUDA/OpenCL which doesn't allow to access indexed
|
||
* component of float3 value.
|
||
*/
|
||
#ifndef __KERNEL_CPU__
|
||
# define IDX(vec, idx) \
|
||
((idx == 0) ? ((vec).x) : ( (idx == 1) ? ((vec).y) : ((vec).z) ))
|
||
#else
|
||
# define IDX(vec, idx) ((vec)[idx])
|
||
#endif
|
||
|
||
/* Ray-Triangle intersection for BVH traversal
|
||
*
|
||
* Sven Woop
|
||
* Watertight Ray/Triangle Intersection
|
||
*
|
||
* http://jcgt.org/published/0002/01/05/paper.pdf
|
||
*/
|
||
|
||
/* Precalculated data for the ray->tri intersection. */
|
||
typedef struct IsectPrecalc {
|
||
/* Maximal dimension kz, and orthogonal dimensions. */
|
||
int kx, ky, kz;
|
||
|
||
/* Shear constants. */
|
||
float Sx, Sy, Sz;
|
||
} IsectPrecalc;
|
||
|
||
/* Workaround for CUDA toolkit 6.5.16. */
|
||
#if defined(__KERNEL_CPU__) || !defined(__KERNEL_CUDA_EXPERIMENTAL__) || __CUDA_ARCH__ < 500
|
||
# if (defined(i386) || defined(_M_IX86))
|
||
ccl_device_noinline
|
||
# else
|
||
ccl_device_inline
|
||
# endif
|
||
#else
|
||
ccl_device_noinline
|
||
#endif
|
||
void triangle_intersect_precalc(float3 dir,
|
||
IsectPrecalc *isect_precalc)
|
||
{
|
||
/* Calculate dimension where the ray direction is maximal. */
|
||
int kz = util_max_axis(make_float3(fabsf(dir.x),
|
||
fabsf(dir.y),
|
||
fabsf(dir.z)));
|
||
int kx = kz + 1; if(kx == 3) kx = 0;
|
||
int ky = kx + 1; if(ky == 3) ky = 0;
|
||
|
||
/* Swap kx and ky dimensions to preserve winding direction of triangles. */
|
||
if(IDX(dir, kz) < 0.0f) {
|
||
int tmp = kx;
|
||
kx = ky;
|
||
ky = tmp;
|
||
}
|
||
|
||
/* Calculate the shear constants. */
|
||
float inf_dir_z = 1.0f / IDX(dir, kz);
|
||
isect_precalc->Sx = IDX(dir, kx) * inf_dir_z;
|
||
isect_precalc->Sy = IDX(dir, ky) * inf_dir_z;
|
||
isect_precalc->Sz = inf_dir_z;
|
||
|
||
/* Store the dimensions. */
|
||
isect_precalc->kx = kx;
|
||
isect_precalc->ky = ky;
|
||
isect_precalc->kz = kz;
|
||
}
|
||
|
||
/* TODO(sergey): Make it general utility function. */
|
||
ccl_device_inline float xor_signmast(float x, int y)
|
||
{
|
||
return __int_as_float(__float_as_int(x) ^ y);
|
||
}
|
||
|
||
ccl_device_inline bool triangle_intersect(KernelGlobals *kg,
|
||
const IsectPrecalc *isect_precalc,
|
||
Intersection *isect,
|
||
float3 P,
|
||
float3 dir,
|
||
uint visibility,
|
||
int object,
|
||
int triAddr)
|
||
{
|
||
const int kx = isect_precalc->kx;
|
||
const int ky = isect_precalc->ky;
|
||
const int kz = isect_precalc->kz;
|
||
const float Sx = isect_precalc->Sx;
|
||
const float Sy = isect_precalc->Sy;
|
||
const float Sz = isect_precalc->Sz;
|
||
|
||
/* Calculate vertices relative to ray origin. */
|
||
float3 tri[3];
|
||
tri[0] = float4_to_float3(kernel_tex_fetch(__tri_woop, triAddr*TRI_NODE_SIZE+0));
|
||
tri[1] = float4_to_float3(kernel_tex_fetch(__tri_woop, triAddr*TRI_NODE_SIZE+1));
|
||
tri[2] = float4_to_float3(kernel_tex_fetch(__tri_woop, triAddr*TRI_NODE_SIZE+2));
|
||
|
||
const float3 A = tri[0] - P;
|
||
const float3 B = tri[1] - P;
|
||
const float3 C = tri[2] - P;
|
||
|
||
const float A_kx = IDX(A, kx), A_ky = IDX(A, ky), A_kz = IDX(A, kz);
|
||
const float B_kx = IDX(B, kx), B_ky = IDX(B, ky), B_kz = IDX(B, kz);
|
||
const float C_kx = IDX(C, kx), C_ky = IDX(C, ky), C_kz = IDX(C, kz);
|
||
|
||
/* Perform shear and scale of vertices. */
|
||
const float Ax = A_kx - Sx * A_kz;
|
||
const float Ay = A_ky - Sy * A_kz;
|
||
const float Bx = B_kx - Sx * B_kz;
|
||
const float By = B_ky - Sy * B_kz;
|
||
const float Cx = C_kx - Sx * C_kz;
|
||
const float Cy = C_ky - Sy * C_kz;
|
||
|
||
/* Calculate scaled barycentric coordinates. */
|
||
float U = Cx * By - Cy * Bx;
|
||
int sign_mask = (__float_as_int(U) & 0x80000000);
|
||
float V = Ax * Cy - Ay * Cx;
|
||
if(sign_mask != (__float_as_int(V) & 0x80000000)) {
|
||
return false;
|
||
}
|
||
float W = Bx * Ay - By * Ax;
|
||
if(sign_mask != (__float_as_int(W) & 0x80000000)) {
|
||
return false;
|
||
}
|
||
|
||
/* Calculate determinant. */
|
||
float det = U + V + W;
|
||
if(UNLIKELY(det == 0.0f)) {
|
||
return false;
|
||
}
|
||
|
||
/* Calculate scaled z−coordinates of vertices and use them to calculate
|
||
* the hit distance.
|
||
*/
|
||
const float T = (U * A_kz + V * B_kz + W * C_kz) * Sz;
|
||
const float sign_T = xor_signmast(T, sign_mask);
|
||
if ((sign_T < 0.0f) ||
|
||
(sign_T > isect->t * xor_signmast(det, sign_mask)))
|
||
{
|
||
return false;
|
||
}
|
||
|
||
#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, triAddr) & visibility)
|
||
#endif
|
||
{
|
||
/* Normalize U, V, W, and T. */
|
||
const float inv_det = 1.0f / det;
|
||
isect->prim = triAddr;
|
||
isect->object = object;
|
||
isect->type = PRIMITIVE_TRIANGLE;
|
||
isect->u = U * inv_det;
|
||
isect->v = V * inv_det;
|
||
isect->t = T * inv_det;
|
||
return true;
|
||
}
|
||
return false;
|
||
}
|
||
|
||
/* Special ray intersection routines for subsurface scattering. In that case we
|
||
* only want to intersect with primitives in the same object, and if case of
|
||
* multiple hits we pick a single random primitive as the intersection point.
|
||
*/
|
||
|
||
#ifdef __SUBSURFACE__
|
||
ccl_device_inline void triangle_intersect_subsurface(
|
||
KernelGlobals *kg,
|
||
const IsectPrecalc *isect_precalc,
|
||
Intersection *isect_array,
|
||
float3 P,
|
||
float3 dir,
|
||
int object,
|
||
int triAddr,
|
||
float tmax,
|
||
uint *num_hits,
|
||
uint *lcg_state,
|
||
int max_hits)
|
||
{
|
||
const int kx = isect_precalc->kx;
|
||
const int ky = isect_precalc->ky;
|
||
const int kz = isect_precalc->kz;
|
||
const float Sx = isect_precalc->Sx;
|
||
const float Sy = isect_precalc->Sy;
|
||
const float Sz = isect_precalc->Sz;
|
||
|
||
/* Calculate vertices relative to ray origin. */
|
||
float3 tri[3];
|
||
tri[0] = float4_to_float3(kernel_tex_fetch(__tri_woop, triAddr*TRI_NODE_SIZE+0));
|
||
tri[1] = float4_to_float3(kernel_tex_fetch(__tri_woop, triAddr*TRI_NODE_SIZE+1));
|
||
tri[2] = float4_to_float3(kernel_tex_fetch(__tri_woop, triAddr*TRI_NODE_SIZE+2));
|
||
|
||
const float3 A = tri[0] - P;
|
||
const float3 B = tri[1] - P;
|
||
const float3 C = tri[2] - P;
|
||
|
||
const float A_kx = IDX(A, kx), A_ky = IDX(A, ky), A_kz = IDX(A, kz);
|
||
const float B_kx = IDX(B, kx), B_ky = IDX(B, ky), B_kz = IDX(B, kz);
|
||
const float C_kx = IDX(C, kx), C_ky = IDX(C, ky), C_kz = IDX(C, kz);
|
||
|
||
/* Perform shear and scale of vertices. */
|
||
const float Ax = A_kx - Sx * A_kz;
|
||
const float Ay = A_ky - Sy * A_kz;
|
||
const float Bx = B_kx - Sx * B_kz;
|
||
const float By = B_ky - Sy * B_kz;
|
||
const float Cx = C_kx - Sx * C_kz;
|
||
const float Cy = C_ky - Sy * C_kz;
|
||
|
||
/* Calculate scaled barycentric coordinates. */
|
||
float U = Cx * By - Cy * Bx;
|
||
int sign_mask = (__float_as_int(U) & 0x80000000);
|
||
float V = Ax * Cy - Ay * Cx;
|
||
if(sign_mask != (__float_as_int(V) & 0x80000000)) {
|
||
return;
|
||
}
|
||
float W = Bx * Ay - By * Ax;
|
||
if(sign_mask != (__float_as_int(W) & 0x80000000)) {
|
||
return;
|
||
}
|
||
|
||
/* Calculate determinant. */
|
||
float det = U + V + W;
|
||
if(UNLIKELY(det == 0.0f)) {
|
||
return;
|
||
}
|
||
|
||
/* Calculate scaled z−coordinates of vertices and use them to calculate
|
||
* the hit distance.
|
||
*/
|
||
const float Az = Sz * A_kz;
|
||
const float Bz = Sz * B_kz;
|
||
const float Cz = Sz * C_kz;
|
||
const float T = U * Az + V * Bz + W * Cz;
|
||
|
||
if ((xor_signmast(T, sign_mask) < 0.0f) ||
|
||
(xor_signmast(T, sign_mask) > tmax * xor_signmast(det, sign_mask)))
|
||
{
|
||
return;
|
||
}
|
||
|
||
/* Normalize U, V, W, and T. */
|
||
const float inv_det = 1.0f / det;
|
||
|
||
(*num_hits)++;
|
||
int hit;
|
||
|
||
if(*num_hits <= max_hits) {
|
||
hit = *num_hits - 1;
|
||
}
|
||
else {
|
||
/* reservoir sampling: if we are at the maximum number of
|
||
* hits, randomly replace element or skip it */
|
||
hit = lcg_step_uint(lcg_state) % *num_hits;
|
||
|
||
if(hit >= max_hits)
|
||
return;
|
||
}
|
||
|
||
/* record intersection */
|
||
Intersection *isect = &isect_array[hit];
|
||
isect->prim = triAddr;
|
||
isect->object = object;
|
||
isect->type = PRIMITIVE_TRIANGLE;
|
||
isect->u = U * inv_det;
|
||
isect->v = V * inv_det;
|
||
isect->t = T * inv_det;
|
||
}
|
||
#endif
|
||
|
||
/* Refine triangle intersection to more precise hit point. For rays that travel
|
||
* far the precision is often not so good, this reintersects the primitive from
|
||
* a closer distance. */
|
||
|
||
/* Reintersections uses the paper:
|
||
*
|
||
* Tomas Moeller
|
||
* Fast, minimum storage ray/triangle intersection
|
||
* http://www.cs.virginia.edu/~gfx/Courses/2003/ImageSynthesis/papers/Acceleration/Fast%20MinimumStorage%20RayTriangle%20Intersection.pdf
|
||
*/
|
||
|
||
ccl_device_inline float3 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 != OBJECT_NONE) {
|
||
if(UNLIKELY(t == 0.0f)) {
|
||
return P;
|
||
}
|
||
#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;
|
||
|
||
float3 tri[3];
|
||
tri[0] = float4_to_float3(kernel_tex_fetch(__tri_woop, isect->prim*TRI_NODE_SIZE+0));
|
||
tri[1] = float4_to_float3(kernel_tex_fetch(__tri_woop, isect->prim*TRI_NODE_SIZE+1));
|
||
tri[2] = float4_to_float3(kernel_tex_fetch(__tri_woop, isect->prim*TRI_NODE_SIZE+2));
|
||
|
||
float3 edge1 = tri[0] - tri[2];
|
||
float3 edge2 = tri[1] - tri[2];
|
||
float3 tvec = P - tri[2];
|
||
float3 qvec = cross(tvec, edge1);
|
||
float3 pvec = cross(D, edge2);
|
||
float rt = dot(edge2, qvec) / dot(edge1, pvec);
|
||
|
||
P = P + D*rt;
|
||
|
||
if(isect->object != OBJECT_NONE) {
|
||
#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
|
||
}
|
||
|
||
/* Same as above, except that isect->t is assumed to be in object space for
|
||
* instancing.
|
||
*/
|
||
ccl_device_inline float3 triangle_refine_subsurface(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 != OBJECT_NONE) {
|
||
#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);
|
||
D = normalize(D);
|
||
}
|
||
|
||
P = P + D*t;
|
||
|
||
float3 tri[3];
|
||
tri[0] = float4_to_float3(kernel_tex_fetch(__tri_woop, isect->prim*TRI_NODE_SIZE+0));
|
||
tri[1] = float4_to_float3(kernel_tex_fetch(__tri_woop, isect->prim*TRI_NODE_SIZE+1));
|
||
tri[2] = float4_to_float3(kernel_tex_fetch(__tri_woop, isect->prim*TRI_NODE_SIZE+2));
|
||
|
||
float3 edge1 = tri[0] - tri[2];
|
||
float3 edge2 = tri[1] - tri[2];
|
||
float3 tvec = P - tri[2];
|
||
float3 qvec = cross(tvec, edge1);
|
||
float3 pvec = cross(D, edge2);
|
||
float rt = dot(edge2, qvec) / dot(edge1, pvec);
|
||
|
||
P = P + D*rt;
|
||
|
||
if(isect->object != OBJECT_NONE) {
|
||
#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
|
||
}
|
||
|
||
#undef IDX
|
||
|
||
CCL_NAMESPACE_END
|