blender/intern/cycles/kernel/geom/geom_qbvh_traversal.h
Sergey Sharybin 5719ed1225 Cycles: Add leaf primitives sanity check asserts to the kernel
This way we'll notice that leaf splitting didn't happen correct pretty easily
in debug builds.

There'll be absolutely no impact on release builds.
2015-01-12 15:05:14 +05:00

413 lines
13 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.
*/
/* This is a template BVH traversal function, 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_HAIR: hair curve rendering
* BVH_HAIR_MINIMUM_WIDTH: hair curve rendering with minimum width
* BVH_MOTION: motion blur rendering
*
*/
ccl_device bool BVH_FUNCTION_FULL_NAME(QBVH)(KernelGlobals *kg,
const Ray *ray,
Intersection *isect,
const uint visibility
#if BVH_FEATURE(BVH_HAIR_MINIMUM_WIDTH)
,uint *lcg_state,
float difl,
float extmax
#endif
)
{
/* TODO(sergey):
* - 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. */
QBVHStackItem traversalStack[BVH_QSTACK_SIZE];
traversalStack[0].addr = ENTRYPOINT_SENTINEL;
traversalStack[0].dist = -FLT_MAX;
/* Traversal variables in registers. */
int stackPtr = 0;
int nodeAddr = kernel_data.bvh.root;
float nodeDist = -FLT_MAX;
/* 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_tfm;
#endif
isect->t = ray->t;
isect->u = 0.0f;
isect->v = 0.0f;
isect->prim = PRIM_NONE;
isect->object = OBJECT_NONE;
#if defined(__KERNEL_DEBUG__)
isect->num_traversal_steps = 0;
#endif
ssef tnear(0.0f), tfar(ray->t);
sse3f idir4(ssef(idir.x), ssef(idir.y), ssef(idir.z));
#ifdef __KERNEL_AVX2__
float3 P_idir = P*idir;
sse3f P_idir4 = sse3f(P_idir.x, P_idir.y, P_idir.z);
#else
sse3f org = sse3f(ssef(P.x), ssef(P.y), ssef(P.z));
#endif
/* Offsets to select the side that becomes the lower or upper bound. */
int near_x, near_y, near_z;
int far_x, far_y, far_z;
if(idir.x >= 0.0f) { near_x = 0; far_x = 1; } else { near_x = 1; far_x = 0; }
if(idir.y >= 0.0f) { near_y = 2; far_y = 3; } else { near_y = 3; far_y = 2; }
if(idir.z >= 0.0f) { near_z = 4; far_z = 5; } else { near_z = 5; far_z = 4; }
IsectPrecalc isect_precalc;
triangle_intersect_precalc(dir, &isect_precalc);
/* Traversal loop. */
do {
do {
/* Traverse internal nodes. */
while(nodeAddr >= 0 && nodeAddr != ENTRYPOINT_SENTINEL) {
if(UNLIKELY(nodeDist > isect->t)) {
/* Pop. */
nodeAddr = traversalStack[stackPtr].addr;
nodeDist = traversalStack[stackPtr].dist;
--stackPtr;
continue;
}
int traverseChild;
ssef dist;
#if defined(__KERNEL_DEBUG__)
isect->num_traversal_steps++;
#endif
#if BVH_FEATURE(BVH_HAIR_MINIMUM_WIDTH)
if(difl != 0.0f) {
/* NOTE: We extend all the child BB instead of fetching
* and checking visibility flags for each of the,
*
* Need to test if doing opposite would be any faster.
*/
traverseChild = qbvh_node_intersect_robust(kg,
tnear,
tfar,
#ifdef __KERNEL_AVX2__
P_idir4,
#else
org,
#endif
idir4,
near_x, near_y, near_z,
far_x, far_y, far_z,
nodeAddr,
difl,
&dist);
}
else
#endif
{
traverseChild = qbvh_node_intersect(kg,
tnear,
tfar,
#ifdef __KERNEL_AVX2__
P_idir4,
#else
org,
#endif
idir4,
near_x, near_y, near_z,
far_x, far_y, far_z,
nodeAddr,
&dist);
}
if(traverseChild != 0) {
float4 cnodes = kernel_tex_fetch(__bvh_nodes, nodeAddr*BVH_QNODE_SIZE+6);
/* One child is hit, continue with that child. */
int r = __bscf(traverseChild);
float d0 = ((float*)&dist)[r];
if(traverseChild == 0) {
nodeAddr = __float_as_int(cnodes[r]);
nodeDist = d0;
continue;
}
/* Two children are hit, push far child, and continue with
* closer child.
*/
int c0 = __float_as_int(cnodes[r]);
r = __bscf(traverseChild);
int c1 = __float_as_int(cnodes[r]);
float d1 = ((float*)&dist)[r];
if(traverseChild == 0) {
if(d1 < d0) {
nodeAddr = c1;
++stackPtr;
kernel_assert(stackPtr < BVH_QSTACK_SIZE);
traversalStack[stackPtr].addr = c0;
traversalStack[stackPtr].dist = d0;
continue;
}
else {
nodeAddr = c0;
++stackPtr;
kernel_assert(stackPtr < BVH_QSTACK_SIZE);
traversalStack[stackPtr].addr = c1;
traversalStack[stackPtr].dist = d1;
continue;
}
}
/* Here starts the slow path for 3 or 4 hit children. We push
* all nodes onto the stack to sort them there.
*/
++stackPtr;
kernel_assert(stackPtr < BVH_QSTACK_SIZE);
traversalStack[stackPtr].addr = c1;
traversalStack[stackPtr].dist = d1;
++stackPtr;
kernel_assert(stackPtr < BVH_QSTACK_SIZE);
traversalStack[stackPtr].addr = c0;
traversalStack[stackPtr].dist = d0;
/* Three children are hit, push all onto stack and sort 3
* stack items, continue with closest child.
*/
r = __bscf(traverseChild);
int c2 = __float_as_int(cnodes[r]);
float d2 = ((float*)&dist)[r];
if(traverseChild == 0) {
++stackPtr;
kernel_assert(stackPtr < BVH_QSTACK_SIZE);
traversalStack[stackPtr].addr = c2;
traversalStack[stackPtr].dist = d2;
qbvh_stack_sort(&traversalStack[stackPtr],
&traversalStack[stackPtr - 1],
&traversalStack[stackPtr - 2]);
nodeAddr = traversalStack[stackPtr].addr;
nodeDist = traversalStack[stackPtr].dist;
--stackPtr;
continue;
}
/* Four children are hit, push all onto stack and sort 4
* stack items, continue with closest child.
*/
r = __bscf(traverseChild);
int c3 = __float_as_int(cnodes[r]);
float d3 = ((float*)&dist)[r];
++stackPtr;
kernel_assert(stackPtr < BVH_QSTACK_SIZE);
traversalStack[stackPtr].addr = c3;
traversalStack[stackPtr].dist = d3;
++stackPtr;
kernel_assert(stackPtr < BVH_QSTACK_SIZE);
traversalStack[stackPtr].addr = c2;
traversalStack[stackPtr].dist = d2;
qbvh_stack_sort(&traversalStack[stackPtr],
&traversalStack[stackPtr - 1],
&traversalStack[stackPtr - 2],
&traversalStack[stackPtr - 3]);
}
nodeAddr = traversalStack[stackPtr].addr;
nodeDist = traversalStack[stackPtr].dist;
--stackPtr;
}
/* If node is leaf, fetch triangle list. */
if(nodeAddr < 0) {
float4 leaf = kernel_tex_fetch(__bvh_nodes, (-nodeAddr-1)*BVH_QNODE_SIZE+6);
#ifdef __VISIBILITY_FLAG__
if(UNLIKELY((nodeDist > isect->t) || ((__float_as_uint(leaf.z) & visibility) == 0)))
#else
if(UNLIKELY((nodeDist > isect->t)))
#endif
{
/* Pop. */
nodeAddr = traversalStack[stackPtr].addr;
nodeDist = traversalStack[stackPtr].dist;
--stackPtr;
continue;
}
int primAddr = __float_as_int(leaf.x);
#if BVH_FEATURE(BVH_INSTANCING)
if(primAddr >= 0) {
#endif
int primAddr2 = __float_as_int(leaf.y);
const uint type = __float_as_int(leaf.w);
/* Pop. */
nodeAddr = traversalStack[stackPtr].addr;
nodeDist = traversalStack[stackPtr].dist;
--stackPtr;
/* Primitive intersection. */
switch(type & PRIMITIVE_ALL) {
case PRIMITIVE_TRIANGLE: {
for(; primAddr < primAddr2; primAddr++) {
#if defined(__KERNEL_DEBUG__)
isect->num_traversal_steps++;
#endif
kernel_assert(kernel_tex_fetch(__prim_type, primAddr) == type);
if(triangle_intersect(kg, &isect_precalc, isect, P, dir, visibility, object, primAddr)) {
tfar = ssef(isect->t);
/* Shadow ray early termination. */
if(visibility == PATH_RAY_SHADOW_OPAQUE)
return true;
}
}
break;
}
#if BVH_FEATURE(BVH_MOTION)
case PRIMITIVE_MOTION_TRIANGLE: {
for(; primAddr < primAddr2; primAddr++) {
#if defined(__KERNEL_DEBUG__)
isect->num_traversal_steps++;
#endif
kernel_assert(kernel_tex_fetch(__prim_type, primAddr) == type);
if(motion_triangle_intersect(kg, isect, P, dir, ray->time, visibility, object, primAddr)) {
tfar = ssef(isect->t);
/* Shadow ray early termination. */
if(visibility == PATH_RAY_SHADOW_OPAQUE)
return true;
}
}
break;
}
#endif /* BVH_FEATURE(BVH_MOTION) */
#if BVH_FEATURE(BVH_HAIR)
case PRIMITIVE_CURVE:
case PRIMITIVE_MOTION_CURVE: {
for(; primAddr < primAddr2; primAddr++) {
#if defined(__KERNEL_DEBUG__)
isect->num_traversal_steps++;
#endif
kernel_assert(kernel_tex_fetch(__prim_type, primAddr) == type);
bool hit;
if(kernel_data.curve.curveflags & CURVE_KN_INTERPOLATE)
hit = bvh_cardinal_curve_intersect(kg, isect, P, dir, visibility, object, primAddr, ray->time, type, lcg_state, difl, extmax);
else
hit = bvh_curve_intersect(kg, isect, P, dir, visibility, object, primAddr, ray->time, type, lcg_state, difl, extmax);
if(hit) {
tfar = ssef(isect->t);
/* Shadow ray early termination. */
if(visibility == PATH_RAY_SHADOW_OPAQUE)
return true;
}
}
break;
}
#endif /* BVH_FEATURE(BVH_HAIR) */
}
}
#if BVH_FEATURE(BVH_INSTANCING)
else {
/* Instance push. */
object = kernel_tex_fetch(__prim_object, -primAddr-1);
#if BVH_FEATURE(BVH_MOTION)
qbvh_instance_motion_push(kg, object, ray, &P, &dir, &idir, &isect->t, &nodeDist, &ob_tfm);
#else
qbvh_instance_push(kg, object, ray, &P, &dir, &idir, &isect->t, &nodeDist);
#endif
if(idir.x >= 0.0f) { near_x = 0; far_x = 1; } else { near_x = 1; far_x = 0; }
if(idir.y >= 0.0f) { near_y = 2; far_y = 3; } else { near_y = 3; far_y = 2; }
if(idir.z >= 0.0f) { near_z = 4; far_z = 5; } else { near_z = 5; far_z = 4; }
tfar = ssef(isect->t);
idir4 = sse3f(ssef(idir.x), ssef(idir.y), ssef(idir.z));
#ifdef __KERNEL_AVX2__
P_idir = P*idir;
P_idir4 = sse3f(P_idir.x, P_idir.y, P_idir.z);
#else
org = sse3f(ssef(P.x), ssef(P.y), ssef(P.z));
#endif
triangle_intersect_precalc(dir, &isect_precalc);
++stackPtr;
kernel_assert(stackPtr < BVH_QSTACK_SIZE);
traversalStack[stackPtr].addr = ENTRYPOINT_SENTINEL;
traversalStack[stackPtr].dist = -FLT_MAX;
nodeAddr = kernel_tex_fetch(__object_node, object);
}
}
#endif /* FEATURE(BVH_INSTANCING) */
} while(nodeAddr != ENTRYPOINT_SENTINEL);
#if BVH_FEATURE(BVH_INSTANCING)
if(stackPtr >= 0) {
kernel_assert(object != OBJECT_NONE);
/* Instance pop. */
#if BVH_FEATURE(BVH_MOTION)
bvh_instance_motion_pop(kg, object, ray, &P, &dir, &idir, &isect->t, &ob_tfm);
#else
bvh_instance_pop(kg, object, ray, &P, &dir, &idir, &isect->t);
#endif
if(idir.x >= 0.0f) { near_x = 0; far_x = 1; } else { near_x = 1; far_x = 0; }
if(idir.y >= 0.0f) { near_y = 2; far_y = 3; } else { near_y = 3; far_y = 2; }
if(idir.z >= 0.0f) { near_z = 4; far_z = 5; } else { near_z = 5; far_z = 4; }
tfar = ssef(isect->t);
idir4 = sse3f(ssef(idir.x), ssef(idir.y), ssef(idir.z));
#ifdef __KERNEL_AVX2__
P_idir = P*idir;
P_idir4 = sse3f(P_idir.x, P_idir.y, P_idir.z);
#else
org = sse3f(ssef(P.x), ssef(P.y), ssef(P.z));
#endif
triangle_intersect_precalc(dir, &isect_precalc);
object = OBJECT_NONE;
nodeAddr = traversalStack[stackPtr].addr;
nodeDist = traversalStack[stackPtr].dist;
--stackPtr;
}
#endif /* FEATURE(BVH_INSTANCING) */
} while(nodeAddr != ENTRYPOINT_SENTINEL);
return (isect->prim != PRIM_NONE);
}