Files
blender/intern/cycles/kernel/bvh/bvh_volume.h
Sergey Sharybin 73f2056052 Cycles: Add BVH8 and packeted triangle intersection
This is an initial implementation of BVH8 optimization structure
and packated triangle intersection. The aim is to get faster ray
to scene intersection checks.

    Scene                BVH4      BVH8
barbershop_interior    10:24.94   10:10.74
bmw27                  02:41.25   02:38.83
classroom              08:16.49   07:56.15
fishy_cat              04:24.56   04:17.29
koro                   06:03.06   06:01.45
pavillon_barcelona     09:21.26   09:02.98
victor                 23:39.65   22:53.71

As memory goes, peak usage raises by about 4.7% in a complex
scenes.

Note that BVH8 is disabled when using OSL, this is because OSL
kernel does not get per-microarchitecture optimizations and
hence always considers BVH3 is used.

Original BVH8 patch from Anton Gavrikov.
Batched triangles intersection from Victoria Zhislina.
Extra work and tests and fixes from Maxym Dmytrychenko.
2018-08-29 15:03:09 +02:00

343 lines
10 KiB
C

/*
* Adapted from code Copyright 2009-2010 NVIDIA Corporation,
* and code copyright 2009-2012 Intel Corporation
*
* Modifications Copyright 2011-2014, 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.
*/
#ifdef __QBVH__
# include "kernel/bvh/qbvh_volume.h"
#ifdef __KERNEL_AVX2__
# include "kernel/bvh/obvh_volume.h"
#endif
#endif
#if BVH_FEATURE(BVH_HAIR)
# define NODE_INTERSECT bvh_node_intersect
#else
# define NODE_INTERSECT bvh_aligned_node_intersect
#endif
/* This is a template BVH traversal function for volumes, where
* various features can be enabled/disabled. This way we can compile optimized
* versions for each case without new features slowing things down.
*
* BVH_INSTANCING: object instancing
* BVH_MOTION: motion blur rendering
*
*/
#ifndef __KERNEL_GPU__
ccl_device
#else
ccl_device_inline
#endif
bool BVH_FUNCTION_FULL_NAME(BVH)(KernelGlobals *kg,
const Ray *ray,
Intersection *isect,
const uint visibility)
{
/* todo:
* - test if pushing distance on the stack helps (for non shadow rays)
* - separate version for shadow rays
* - likely and unlikely for if() statements
* - test restrict attribute for pointers
*/
/* traversal stack in CUDA thread-local memory */
int traversal_stack[BVH_STACK_SIZE];
traversal_stack[0] = ENTRYPOINT_SENTINEL;
/* traversal variables in registers */
int stack_ptr = 0;
int node_addr = kernel_data.bvh.root;
/* ray parameters in registers */
float3 P = ray->P;
float3 dir = bvh_clamp_direction(ray->D);
float3 idir = bvh_inverse_direction(dir);
int object = OBJECT_NONE;
#if BVH_FEATURE(BVH_MOTION)
Transform ob_itfm;
#endif
isect->t = ray->t;
isect->u = 0.0f;
isect->v = 0.0f;
isect->prim = PRIM_NONE;
isect->object = OBJECT_NONE;
#if defined(__KERNEL_SSE2__)
const shuffle_swap_t shuf_identity = shuffle_swap_identity();
const shuffle_swap_t shuf_swap = shuffle_swap_swap();
const ssef pn = cast(ssei(0, 0, 0x80000000, 0x80000000));
ssef Psplat[3], idirsplat[3];
# if BVH_FEATURE(BVH_HAIR)
ssef tnear(0.0f), tfar(isect->t);
# endif
shuffle_swap_t shufflexyz[3];
Psplat[0] = ssef(P.x);
Psplat[1] = ssef(P.y);
Psplat[2] = ssef(P.z);
ssef tsplat(0.0f, 0.0f, -isect->t, -isect->t);
gen_idirsplat_swap(pn, shuf_identity, shuf_swap, idir, idirsplat, shufflexyz);
#endif
/* traversal loop */
do {
do {
/* traverse internal nodes */
while(node_addr >= 0 && node_addr != ENTRYPOINT_SENTINEL) {
int node_addr_child1, traverse_mask;
float dist[2];
float4 cnodes = kernel_tex_fetch(__bvh_nodes, node_addr+0);
#if !defined(__KERNEL_SSE2__)
traverse_mask = NODE_INTERSECT(kg,
P,
# if BVH_FEATURE(BVH_HAIR)
dir,
# endif
idir,
isect->t,
node_addr,
visibility,
dist);
#else // __KERNEL_SSE2__
traverse_mask = NODE_INTERSECT(kg,
P,
dir,
# if BVH_FEATURE(BVH_HAIR)
tnear,
tfar,
# endif
tsplat,
Psplat,
idirsplat,
shufflexyz,
node_addr,
visibility,
dist);
#endif // __KERNEL_SSE2__
node_addr = __float_as_int(cnodes.z);
node_addr_child1 = __float_as_int(cnodes.w);
if(traverse_mask == 3) {
/* Both children were intersected, push the farther one. */
bool is_closest_child1 = (dist[1] < dist[0]);
if(is_closest_child1) {
int tmp = node_addr;
node_addr = node_addr_child1;
node_addr_child1 = tmp;
}
++stack_ptr;
kernel_assert(stack_ptr < BVH_STACK_SIZE);
traversal_stack[stack_ptr] = node_addr_child1;
}
else {
/* One child was intersected. */
if(traverse_mask == 2) {
node_addr = node_addr_child1;
}
else if(traverse_mask == 0) {
/* Neither child was intersected. */
node_addr = traversal_stack[stack_ptr];
--stack_ptr;
}
}
}
/* if node is leaf, fetch triangle list */
if(node_addr < 0) {
float4 leaf = kernel_tex_fetch(__bvh_leaf_nodes, (-node_addr-1));
int prim_addr = __float_as_int(leaf.x);
#if BVH_FEATURE(BVH_INSTANCING)
if(prim_addr >= 0) {
#endif
const int prim_addr2 = __float_as_int(leaf.y);
const uint type = __float_as_int(leaf.w);
/* pop */
node_addr = traversal_stack[stack_ptr];
--stack_ptr;
/* primitive intersection */
switch(type & PRIMITIVE_ALL) {
case PRIMITIVE_TRIANGLE: {
/* intersect ray against primitive */
for(; prim_addr < prim_addr2; prim_addr++) {
kernel_assert(kernel_tex_fetch(__prim_type, prim_addr) == type);
/* only primitives from volume object */
uint tri_object = (object == OBJECT_NONE)? kernel_tex_fetch(__prim_object, prim_addr): object;
int object_flag = kernel_tex_fetch(__object_flag, tri_object);
if((object_flag & SD_OBJECT_HAS_VOLUME) == 0) {
continue;
}
triangle_intersect(kg,
isect,
P,
dir,
visibility,
object,
prim_addr);
}
break;
}
#if BVH_FEATURE(BVH_MOTION)
case PRIMITIVE_MOTION_TRIANGLE: {
/* intersect ray against primitive */
for(; prim_addr < prim_addr2; prim_addr++) {
kernel_assert(kernel_tex_fetch(__prim_type, prim_addr) == type);
/* only primitives from volume object */
uint tri_object = (object == OBJECT_NONE)? kernel_tex_fetch(__prim_object, prim_addr): object;
int object_flag = kernel_tex_fetch(__object_flag, tri_object);
if((object_flag & SD_OBJECT_HAS_VOLUME) == 0) {
continue;
}
motion_triangle_intersect(kg,
isect,
P,
dir,
ray->time,
visibility,
object,
prim_addr);
}
break;
}
#endif
default: {
break;
}
}
}
#if BVH_FEATURE(BVH_INSTANCING)
else {
/* instance push */
object = kernel_tex_fetch(__prim_object, -prim_addr-1);
int object_flag = kernel_tex_fetch(__object_flag, object);
if(object_flag & SD_OBJECT_HAS_VOLUME) {
# if BVH_FEATURE(BVH_MOTION)
isect->t = bvh_instance_motion_push(kg, object, ray, &P, &dir, &idir, isect->t, &ob_itfm);
# else
isect->t = bvh_instance_push(kg, object, ray, &P, &dir, &idir, isect->t);
# endif
# if defined(__KERNEL_SSE2__)
Psplat[0] = ssef(P.x);
Psplat[1] = ssef(P.y);
Psplat[2] = ssef(P.z);
tsplat = ssef(0.0f, 0.0f, -isect->t, -isect->t);
# if BVH_FEATURE(BVH_HAIR)
tfar = ssef(isect->t);
# endif
gen_idirsplat_swap(pn, shuf_identity, shuf_swap, idir, idirsplat, shufflexyz);
# endif
++stack_ptr;
kernel_assert(stack_ptr < BVH_STACK_SIZE);
traversal_stack[stack_ptr] = ENTRYPOINT_SENTINEL;
node_addr = kernel_tex_fetch(__object_node, object);
}
else {
/* pop */
object = OBJECT_NONE;
node_addr = traversal_stack[stack_ptr];
--stack_ptr;
}
}
}
#endif /* FEATURE(BVH_INSTANCING) */
} while(node_addr != ENTRYPOINT_SENTINEL);
#if BVH_FEATURE(BVH_INSTANCING)
if(stack_ptr >= 0) {
kernel_assert(object != OBJECT_NONE);
/* instance pop */
# if BVH_FEATURE(BVH_MOTION)
isect->t = bvh_instance_motion_pop(kg, object, ray, &P, &dir, &idir, isect->t, &ob_itfm);
# else
isect->t = bvh_instance_pop(kg, object, ray, &P, &dir, &idir, isect->t);
# endif
# if defined(__KERNEL_SSE2__)
Psplat[0] = ssef(P.x);
Psplat[1] = ssef(P.y);
Psplat[2] = ssef(P.z);
tsplat = ssef(0.0f, 0.0f, -isect->t, -isect->t);
# if BVH_FEATURE(BVH_HAIR)
tfar = ssef(isect->t);
# endif
gen_idirsplat_swap(pn, shuf_identity, shuf_swap, idir, idirsplat, shufflexyz);
# endif
object = OBJECT_NONE;
node_addr = traversal_stack[stack_ptr];
--stack_ptr;
}
#endif /* FEATURE(BVH_MOTION) */
} while(node_addr != ENTRYPOINT_SENTINEL);
return (isect->prim != PRIM_NONE);
}
ccl_device_inline bool BVH_FUNCTION_NAME(KernelGlobals *kg,
const Ray *ray,
Intersection *isect,
const uint visibility)
{
switch(kernel_data.bvh.bvh_layout) {
#ifdef __KERNEL_AVX2__
case BVH_LAYOUT_BVH8:
return BVH_FUNCTION_FULL_NAME(OBVH)(kg,
ray,
isect,
visibility);
#endif
#ifdef __QBVH__
case BVH_LAYOUT_BVH4:
return BVH_FUNCTION_FULL_NAME(QBVH)(kg,
ray,
isect,
visibility);
#endif
case BVH_LAYOUT_BVH2:
return BVH_FUNCTION_FULL_NAME(BVH)(kg,
ray,
isect,
visibility);
}
kernel_assert(!"Should not happen");
return false;
}
#undef BVH_FUNCTION_NAME
#undef BVH_FUNCTION_FEATURES
#undef NODE_INTERSECT