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|
/*
* Copyright 2011-2013 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.
*/
/* BVH
*
* Bounding volume hierarchy for ray tracing. We compile different variations
* of the same BVH traversal function for faster rendering when some types of
* primitives are not needed, using #includes to work around the lack of
* C++ templates in OpenCL.
*
* Originally based on "Understanding the Efficiency of Ray Traversal on GPUs",
* the code has been extended and modified to support more primitives and work
* with CPU/CUDA/OpenCL. */
#ifdef __EMBREE__
# include "kernel/bvh/bvh_embree.h"
#endif
CCL_NAMESPACE_BEGIN
#include "kernel/bvh/bvh_types.h"
#ifndef __KERNEL_OPTIX__
/* Common QBVH functions. */
# ifdef __QBVH__
# include "kernel/bvh/qbvh_nodes.h"
# ifdef __KERNEL_AVX2__
# include "kernel/bvh/obvh_nodes.h"
# endif
# endif
/* Regular BVH traversal */
# include "kernel/bvh/bvh_nodes.h"
# define BVH_FUNCTION_NAME bvh_intersect
# define BVH_FUNCTION_FEATURES 0
# include "kernel/bvh/bvh_traversal.h"
# if defined(__INSTANCING__)
# define BVH_FUNCTION_NAME bvh_intersect_instancing
# define BVH_FUNCTION_FEATURES BVH_INSTANCING
# include "kernel/bvh/bvh_traversal.h"
# endif
# if defined(__HAIR__)
# define BVH_FUNCTION_NAME bvh_intersect_hair
# define BVH_FUNCTION_FEATURES BVH_INSTANCING | BVH_HAIR
# include "kernel/bvh/bvh_traversal.h"
# endif
# if defined(__OBJECT_MOTION__)
# define BVH_FUNCTION_NAME bvh_intersect_motion
# define BVH_FUNCTION_FEATURES BVH_INSTANCING | BVH_MOTION
# include "kernel/bvh/bvh_traversal.h"
# endif
# if defined(__HAIR__) && defined(__OBJECT_MOTION__)
# define BVH_FUNCTION_NAME bvh_intersect_hair_motion
# define BVH_FUNCTION_FEATURES BVH_INSTANCING | BVH_HAIR | BVH_MOTION
# include "kernel/bvh/bvh_traversal.h"
# endif
/* Subsurface scattering BVH traversal */
# if defined(__BVH_LOCAL__)
# define BVH_FUNCTION_NAME bvh_intersect_local
# define BVH_FUNCTION_FEATURES BVH_HAIR
# include "kernel/bvh/bvh_local.h"
# if defined(__OBJECT_MOTION__)
# define BVH_FUNCTION_NAME bvh_intersect_local_motion
# define BVH_FUNCTION_FEATURES BVH_MOTION | BVH_HAIR
# include "kernel/bvh/bvh_local.h"
# endif
# endif /* __BVH_LOCAL__ */
/* Volume BVH traversal */
# if defined(__VOLUME__)
# define BVH_FUNCTION_NAME bvh_intersect_volume
# define BVH_FUNCTION_FEATURES BVH_HAIR
# include "kernel/bvh/bvh_volume.h"
# if defined(__INSTANCING__)
# define BVH_FUNCTION_NAME bvh_intersect_volume_instancing
# define BVH_FUNCTION_FEATURES BVH_INSTANCING | BVH_HAIR
# include "kernel/bvh/bvh_volume.h"
# endif
# if defined(__OBJECT_MOTION__)
# define BVH_FUNCTION_NAME bvh_intersect_volume_motion
# define BVH_FUNCTION_FEATURES BVH_INSTANCING | BVH_MOTION | BVH_HAIR
# include "kernel/bvh/bvh_volume.h"
# endif
# endif /* __VOLUME__ */
/* Record all intersections - Shadow BVH traversal */
# if defined(__SHADOW_RECORD_ALL__)
# define BVH_FUNCTION_NAME bvh_intersect_shadow_all
# define BVH_FUNCTION_FEATURES 0
# include "kernel/bvh/bvh_shadow_all.h"
# if defined(__INSTANCING__)
# define BVH_FUNCTION_NAME bvh_intersect_shadow_all_instancing
# define BVH_FUNCTION_FEATURES BVH_INSTANCING
# include "kernel/bvh/bvh_shadow_all.h"
# endif
# if defined(__HAIR__)
# define BVH_FUNCTION_NAME bvh_intersect_shadow_all_hair
# define BVH_FUNCTION_FEATURES BVH_INSTANCING | BVH_HAIR
# include "kernel/bvh/bvh_shadow_all.h"
# endif
# if defined(__OBJECT_MOTION__)
# define BVH_FUNCTION_NAME bvh_intersect_shadow_all_motion
# define BVH_FUNCTION_FEATURES BVH_INSTANCING | BVH_MOTION
# include "kernel/bvh/bvh_shadow_all.h"
# endif
# if defined(__HAIR__) && defined(__OBJECT_MOTION__)
# define BVH_FUNCTION_NAME bvh_intersect_shadow_all_hair_motion
# define BVH_FUNCTION_FEATURES BVH_INSTANCING | BVH_HAIR | BVH_MOTION
# include "kernel/bvh/bvh_shadow_all.h"
# endif
# endif /* __SHADOW_RECORD_ALL__ */
/* Record all intersections - Volume BVH traversal */
# if defined(__VOLUME_RECORD_ALL__)
# define BVH_FUNCTION_NAME bvh_intersect_volume_all
# define BVH_FUNCTION_FEATURES BVH_HAIR
# include "kernel/bvh/bvh_volume_all.h"
# if defined(__INSTANCING__)
# define BVH_FUNCTION_NAME bvh_intersect_volume_all_instancing
# define BVH_FUNCTION_FEATURES BVH_INSTANCING | BVH_HAIR
# include "kernel/bvh/bvh_volume_all.h"
# endif
# if defined(__OBJECT_MOTION__)
# define BVH_FUNCTION_NAME bvh_intersect_volume_all_motion
# define BVH_FUNCTION_FEATURES BVH_INSTANCING | BVH_MOTION | BVH_HAIR
# include "kernel/bvh/bvh_volume_all.h"
# endif
# endif /* __VOLUME_RECORD_ALL__ */
# undef BVH_FEATURE
# undef BVH_NAME_JOIN
# undef BVH_NAME_EVAL
# undef BVH_FUNCTION_FULL_NAME
#endif /* __KERNEL_OPTIX__ */
ccl_device_inline bool scene_intersect_valid(const Ray *ray)
{
/* NOTE: Due to some vectorization code non-finite origin point might
* cause lots of false-positive intersections which will overflow traversal
* stack.
* This code is a quick way to perform early output, to avoid crashes in
* such cases.
* From production scenes so far it seems it's enough to test first element
* only.
* Scene intersection may also called with empty rays for conditional trace
* calls that evaluate to false, so filter those out.
*/
return isfinite_safe(ray->P.x) && isfinite_safe(ray->D.x) && len_squared(ray->D) != 0.0f;
}
ccl_device_intersect bool scene_intersect(KernelGlobals *kg,
const Ray *ray,
const uint visibility,
Intersection *isect)
{
PROFILING_INIT(kg, PROFILING_INTERSECT);
#ifdef __KERNEL_OPTIX__
uint p0 = 0;
uint p1 = 0;
uint p2 = 0;
uint p3 = 0;
uint p4 = visibility;
uint p5 = PRIMITIVE_NONE;
optixTrace(scene_intersect_valid(ray) ? kernel_data.bvh.scene : 0,
ray->P,
ray->D,
0.0f,
ray->t,
ray->time,
0xFF,
OPTIX_RAY_FLAG_NONE,
0,
0,
0, // SBT offset for PG_HITD
p0,
p1,
p2,
p3,
p4,
p5);
isect->t = __uint_as_float(p0);
isect->u = __uint_as_float(p1);
isect->v = __uint_as_float(p2);
isect->prim = p3;
isect->object = p4;
isect->type = p5;
return p5 != PRIMITIVE_NONE;
#else /* __KERNEL_OPTIX__ */
if (!scene_intersect_valid(ray)) {
return false;
}
# ifdef __EMBREE__
if (kernel_data.bvh.scene) {
isect->t = ray->t;
CCLIntersectContext ctx(kg, CCLIntersectContext::RAY_REGULAR);
IntersectContext rtc_ctx(&ctx);
RTCRayHit ray_hit;
kernel_embree_setup_rayhit(*ray, ray_hit, visibility);
rtcIntersect1(kernel_data.bvh.scene, &rtc_ctx.context, &ray_hit);
if (ray_hit.hit.geomID != RTC_INVALID_GEOMETRY_ID &&
ray_hit.hit.primID != RTC_INVALID_GEOMETRY_ID) {
kernel_embree_convert_hit(kg, &ray_hit.ray, &ray_hit.hit, isect);
return true;
}
return false;
}
# endif /* __EMBREE__ */
# ifdef __OBJECT_MOTION__
if (kernel_data.bvh.have_motion) {
# ifdef __HAIR__
if (kernel_data.bvh.have_curves) {
return bvh_intersect_hair_motion(kg, ray, isect, visibility);
}
# endif /* __HAIR__ */
return bvh_intersect_motion(kg, ray, isect, visibility);
}
# endif /* __OBJECT_MOTION__ */
# ifdef __HAIR__
if (kernel_data.bvh.have_curves) {
return bvh_intersect_hair(kg, ray, isect, visibility);
}
# endif /* __HAIR__ */
# ifdef __KERNEL_CPU__
# ifdef __INSTANCING__
if (kernel_data.bvh.have_instancing) {
return bvh_intersect_instancing(kg, ray, isect, visibility);
}
# endif /* __INSTANCING__ */
return bvh_intersect(kg, ray, isect, visibility);
# else /* __KERNEL_CPU__ */
# ifdef __INSTANCING__
return bvh_intersect_instancing(kg, ray, isect, visibility);
# else
return bvh_intersect(kg, ray, isect, visibility);
# endif /* __INSTANCING__ */
# endif /* __KERNEL_CPU__ */
#endif /* __KERNEL_OPTIX__ */
}
#ifdef __BVH_LOCAL__
ccl_device_intersect bool scene_intersect_local(KernelGlobals *kg,
const Ray *ray,
LocalIntersection *local_isect,
int local_object,
uint *lcg_state,
int max_hits)
{
PROFILING_INIT(kg, PROFILING_INTERSECT_LOCAL);
# ifdef __KERNEL_OPTIX__
uint p0 = ((uint64_t)lcg_state) & 0xFFFFFFFF;
uint p1 = (((uint64_t)lcg_state) >> 32) & 0xFFFFFFFF;
uint p2 = ((uint64_t)local_isect) & 0xFFFFFFFF;
uint p3 = (((uint64_t)local_isect) >> 32) & 0xFFFFFFFF;
uint p4 = local_object;
// Is set to zero on miss or if ray is aborted, so can be used as return value
uint p5 = max_hits;
local_isect->num_hits = 0; // Initialize hit count to zero
optixTrace(scene_intersect_valid(ray) ? kernel_data.bvh.scene : 0,
ray->P,
ray->D,
0.0f,
ray->t,
ray->time,
// Need to always call into __anyhit__kernel_optix_local_hit
0xFF,
OPTIX_RAY_FLAG_ENFORCE_ANYHIT,
1,
0,
0, // SBT offset for PG_HITL
p0,
p1,
p2,
p3,
p4,
p5);
return p5;
# else /* __KERNEL_OPTIX__ */
if (!scene_intersect_valid(ray)) {
local_isect->num_hits = 0;
return false;
}
# ifdef __EMBREE__
if (kernel_data.bvh.scene) {
CCLIntersectContext ctx(kg, CCLIntersectContext::RAY_SSS);
ctx.lcg_state = lcg_state;
ctx.max_hits = max_hits;
ctx.ss_isect = local_isect;
local_isect->num_hits = 0;
ctx.sss_object_id = local_object;
IntersectContext rtc_ctx(&ctx);
RTCRay rtc_ray;
kernel_embree_setup_ray(*ray, rtc_ray, PATH_RAY_ALL_VISIBILITY);
/* Get the Embree scene for this intersection. */
RTCGeometry geom = rtcGetGeometry(kernel_data.bvh.scene, local_object * 2);
if (geom) {
float3 P = ray->P;
float3 dir = ray->D;
float3 idir = ray->D;
const int object_flag = kernel_tex_fetch(__object_flag, local_object);
if (!(object_flag & SD_OBJECT_TRANSFORM_APPLIED)) {
Transform ob_itfm;
rtc_ray.tfar = bvh_instance_motion_push(
kg, local_object, ray, &P, &dir, &idir, ray->t, &ob_itfm);
/* bvh_instance_motion_push() returns the inverse transform but
* it's not needed here. */
(void)ob_itfm;
rtc_ray.org_x = P.x;
rtc_ray.org_y = P.y;
rtc_ray.org_z = P.z;
rtc_ray.dir_x = dir.x;
rtc_ray.dir_y = dir.y;
rtc_ray.dir_z = dir.z;
}
RTCScene scene = (RTCScene)rtcGetGeometryUserData(geom);
if (scene) {
rtcOccluded1(scene, &rtc_ctx.context, &rtc_ray);
}
}
return local_isect->num_hits > 0;
}
# endif /* __EMBREE__ */
# ifdef __OBJECT_MOTION__
if (kernel_data.bvh.have_motion) {
return bvh_intersect_local_motion(kg, ray, local_isect, local_object, lcg_state, max_hits);
}
# endif /* __OBJECT_MOTION__ */
return bvh_intersect_local(kg, ray, local_isect, local_object, lcg_state, max_hits);
# endif /* __KERNEL_OPTIX__ */
}
#endif
#ifdef __SHADOW_RECORD_ALL__
ccl_device_intersect bool scene_intersect_shadow_all(KernelGlobals *kg,
const Ray *ray,
Intersection *isect,
uint visibility,
uint max_hits,
uint *num_hits)
{
PROFILING_INIT(kg, PROFILING_INTERSECT_SHADOW_ALL);
# ifdef __KERNEL_OPTIX__
uint p0 = ((uint64_t)isect) & 0xFFFFFFFF;
uint p1 = (((uint64_t)isect) >> 32) & 0xFFFFFFFF;
uint p3 = max_hits;
uint p4 = visibility;
uint p5 = false;
*num_hits = 0; // Initialize hit count to zero
optixTrace(scene_intersect_valid(ray) ? kernel_data.bvh.scene : 0,
ray->P,
ray->D,
0.0f,
ray->t,
ray->time,
// Need to always call into __anyhit__kernel_optix_shadow_all_hit
0xFF,
OPTIX_RAY_FLAG_ENFORCE_ANYHIT,
2,
0,
0, // SBT offset for PG_HITS
p0,
p1,
*num_hits,
p3,
p4,
p5);
return p5;
# else /* __KERNEL_OPTIX__ */
if (!scene_intersect_valid(ray)) {
*num_hits = 0;
return false;
}
# ifdef __EMBREE__
if (kernel_data.bvh.scene) {
CCLIntersectContext ctx(kg, CCLIntersectContext::RAY_SHADOW_ALL);
ctx.isect_s = isect;
ctx.max_hits = max_hits;
ctx.num_hits = 0;
IntersectContext rtc_ctx(&ctx);
RTCRay rtc_ray;
kernel_embree_setup_ray(*ray, rtc_ray, PATH_RAY_SHADOW);
rtcOccluded1(kernel_data.bvh.scene, &rtc_ctx.context, &rtc_ray);
if (ctx.num_hits > max_hits) {
return true;
}
*num_hits = ctx.num_hits;
return rtc_ray.tfar == -INFINITY;
}
# endif /* __EMBREE__ */
# ifdef __OBJECT_MOTION__
if (kernel_data.bvh.have_motion) {
# ifdef __HAIR__
if (kernel_data.bvh.have_curves) {
return bvh_intersect_shadow_all_hair_motion(kg, ray, isect, visibility, max_hits, num_hits);
}
# endif /* __HAIR__ */
return bvh_intersect_shadow_all_motion(kg, ray, isect, visibility, max_hits, num_hits);
}
# endif /* __OBJECT_MOTION__ */
# ifdef __HAIR__
if (kernel_data.bvh.have_curves) {
return bvh_intersect_shadow_all_hair(kg, ray, isect, visibility, max_hits, num_hits);
}
# endif /* __HAIR__ */
# ifdef __KERNEL_CPU__
# ifdef __INSTANCING__
if (kernel_data.bvh.have_instancing) {
return bvh_intersect_shadow_all_instancing(kg, ray, isect, visibility, max_hits, num_hits);
}
# endif /* __INSTANCING__ */
return bvh_intersect_shadow_all(kg, ray, isect, visibility, max_hits, num_hits);
# else
# ifdef __INSTANCING__
return bvh_intersect_shadow_all_instancing(kg, ray, isect, visibility, max_hits, num_hits);
# else
return bvh_intersect_shadow_all(kg, ray, isect, visibility, max_hits, num_hits);
# endif /* __INSTANCING__ */
# endif /* __KERNEL_CPU__ */
# endif /* __KERNEL_OPTIX__ */
}
#endif /* __SHADOW_RECORD_ALL__ */
#ifdef __VOLUME__
ccl_device_intersect bool scene_intersect_volume(KernelGlobals *kg,
const Ray *ray,
Intersection *isect,
const uint visibility)
{
PROFILING_INIT(kg, PROFILING_INTERSECT_VOLUME);
# ifdef __KERNEL_OPTIX__
uint p0 = 0;
uint p1 = 0;
uint p2 = 0;
uint p3 = 0;
uint p4 = visibility;
uint p5 = PRIMITIVE_NONE;
optixTrace(scene_intersect_valid(ray) ? kernel_data.bvh.scene : 0,
ray->P,
ray->D,
0.0f,
ray->t,
ray->time,
// Visibility mask set to only intersect objects with volumes
0x02,
OPTIX_RAY_FLAG_NONE,
0,
0,
0, // SBT offset for PG_HITD
p0,
p1,
p2,
p3,
p4,
p5);
isect->t = __uint_as_float(p0);
isect->u = __uint_as_float(p1);
isect->v = __uint_as_float(p2);
isect->prim = p3;
isect->object = p4;
isect->type = p5;
return p5 != PRIMITIVE_NONE;
# else /* __KERNEL_OPTIX__ */
if (!scene_intersect_valid(ray)) {
return false;
}
# ifdef __OBJECT_MOTION__
if (kernel_data.bvh.have_motion) {
return bvh_intersect_volume_motion(kg, ray, isect, visibility);
}
# endif /* __OBJECT_MOTION__ */
# ifdef __KERNEL_CPU__
# ifdef __INSTANCING__
if (kernel_data.bvh.have_instancing) {
return bvh_intersect_volume_instancing(kg, ray, isect, visibility);
}
# endif /* __INSTANCING__ */
return bvh_intersect_volume(kg, ray, isect, visibility);
# else /* __KERNEL_CPU__ */
# ifdef __INSTANCING__
return bvh_intersect_volume_instancing(kg, ray, isect, visibility);
# else
return bvh_intersect_volume(kg, ray, isect, visibility);
# endif /* __INSTANCING__ */
# endif /* __KERNEL_CPU__ */
# endif /* __KERNEL_OPTIX__ */
}
#endif /* __VOLUME__ */
#ifdef __VOLUME_RECORD_ALL__
ccl_device_intersect uint scene_intersect_volume_all(KernelGlobals *kg,
const Ray *ray,
Intersection *isect,
const uint max_hits,
const uint visibility)
{
PROFILING_INIT(kg, PROFILING_INTERSECT_VOLUME_ALL);
if (!scene_intersect_valid(ray)) {
return false;
}
# ifdef __EMBREE__
if (kernel_data.bvh.scene) {
CCLIntersectContext ctx(kg, CCLIntersectContext::RAY_VOLUME_ALL);
ctx.isect_s = isect;
ctx.max_hits = max_hits;
ctx.num_hits = 0;
IntersectContext rtc_ctx(&ctx);
RTCRay rtc_ray;
kernel_embree_setup_ray(*ray, rtc_ray, visibility);
rtcOccluded1(kernel_data.bvh.scene, &rtc_ctx.context, &rtc_ray);
return rtc_ray.tfar == -INFINITY;
}
# endif /* __EMBREE__ */
# ifdef __OBJECT_MOTION__
if (kernel_data.bvh.have_motion) {
return bvh_intersect_volume_all_motion(kg, ray, isect, max_hits, visibility);
}
# endif /* __OBJECT_MOTION__ */
# ifdef __INSTANCING__
if (kernel_data.bvh.have_instancing) {
return bvh_intersect_volume_all_instancing(kg, ray, isect, max_hits, visibility);
}
# endif /* __INSTANCING__ */
return bvh_intersect_volume_all(kg, ray, isect, max_hits, visibility);
}
#endif /* __VOLUME_RECORD_ALL__ */
/* Ray offset to avoid self intersection.
*
* This function should be used to compute a modified ray start position for
* rays leaving from a surface. */
ccl_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 and motion blur
* 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
}
#if defined(__VOLUME_RECORD_ALL__) || (defined(__SHADOW_RECORD_ALL__) && defined(__KERNEL_CPU__))
/* ToDo: Move to another file? */
ccl_device int intersections_compare(const void *a, const void *b)
{
const Intersection *isect_a = (const Intersection *)a;
const Intersection *isect_b = (const Intersection *)b;
if (isect_a->t < isect_b->t)
return -1;
else if (isect_a->t > isect_b->t)
return 1;
else
return 0;
}
#endif
#if defined(__SHADOW_RECORD_ALL__)
ccl_device_inline void sort_intersections(Intersection *hits, uint num_hits)
{
# ifdef __KERNEL_GPU__
/* Use bubble sort which has more friendly memory pattern on GPU. */
bool swapped;
do {
swapped = false;
for (int j = 0; j < num_hits - 1; ++j) {
if (hits[j].t > hits[j + 1].t) {
struct Intersection tmp = hits[j];
hits[j] = hits[j + 1];
hits[j + 1] = tmp;
swapped = true;
}
}
--num_hits;
} while (swapped);
# else
qsort(hits, num_hits, sizeof(Intersection), intersections_compare);
# endif
}
#endif /* __SHADOW_RECORD_ALL__ | __VOLUME_RECORD_ALL__ */
CCL_NAMESPACE_END
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