diff options
Diffstat (limited to 'intern/cycles/kernel/bvh/traversal.h')
| -rw-r--r-- | intern/cycles/kernel/bvh/traversal.h | 241 |
1 files changed, 241 insertions, 0 deletions
diff --git a/intern/cycles/kernel/bvh/traversal.h b/intern/cycles/kernel/bvh/traversal.h new file mode 100644 index 00000000000..1c17ebf767f --- /dev/null +++ b/intern/cycles/kernel/bvh/traversal.h @@ -0,0 +1,241 @@ +/* + * Adapted from code Copyright 2009-2010 NVIDIA Corporation, + * and code copyright 2009-2012 Intel Corporation + * + * Modifications 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. + */ + +#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, where various features can be + * enabled/disabled. This way we can compile optimized versions for each case + * without new features slowing things down. + * + * BVH_HAIR: hair curve rendering + * BVH_MOTION: motion blur rendering + */ + +ccl_device_noinline bool BVH_FUNCTION_FULL_NAME(BVH)(KernelGlobals kg, + ccl_private const Ray *ray, + ccl_private 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; + + /* 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); + + { + traverse_mask = NODE_INTERSECT(kg, + P, +#if BVH_FEATURE(BVH_HAIR) + dir, +#endif + idir, + isect->t, + node_addr, + visibility, + dist); + } + + 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 (prim_addr >= 0) { + 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: { + for (; prim_addr < prim_addr2; prim_addr++) { + kernel_assert(kernel_tex_fetch(__prim_type, prim_addr) == type); + if (triangle_intersect( + kg, isect, P, dir, isect->t, visibility, object, prim_addr)) { + /* shadow ray early termination */ + if (visibility & PATH_RAY_SHADOW_OPAQUE) + return true; + } + } + break; + } +#if BVH_FEATURE(BVH_MOTION) + case PRIMITIVE_MOTION_TRIANGLE: { + for (; prim_addr < prim_addr2; prim_addr++) { + kernel_assert(kernel_tex_fetch(__prim_type, prim_addr) == type); + if (motion_triangle_intersect( + kg, isect, P, dir, isect->t, ray->time, visibility, object, prim_addr)) { + /* 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_THICK: + case PRIMITIVE_MOTION_CURVE_THICK: + case PRIMITIVE_CURVE_RIBBON: + case PRIMITIVE_MOTION_CURVE_RIBBON: { + for (; prim_addr < prim_addr2; prim_addr++) { + if ((type & PRIMITIVE_ALL_MOTION) && kernel_data.bvh.use_bvh_steps) { + const float2 prim_time = kernel_tex_fetch(__prim_time, prim_addr); + if (ray->time < prim_time.x || ray->time > prim_time.y) { + continue; + } + } + + const int curve_object = (object == OBJECT_NONE) ? + kernel_tex_fetch(__prim_object, prim_addr) : + object; + const int curve_prim = kernel_tex_fetch(__prim_index, prim_addr); + const int curve_type = kernel_tex_fetch(__prim_type, prim_addr); + const bool hit = curve_intersect( + kg, isect, P, dir, isect->t, curve_object, curve_prim, ray->time, curve_type); + if (hit) { + /* shadow ray early termination */ + if (visibility & PATH_RAY_SHADOW_OPAQUE) + return true; + } + } + break; + } +#endif /* BVH_FEATURE(BVH_HAIR) */ + } + } + else { + /* instance push */ + object = kernel_tex_fetch(__prim_object, -prim_addr - 1); + +#if BVH_FEATURE(BVH_MOTION) + isect->t *= bvh_instance_motion_push(kg, object, ray, &P, &dir, &idir, &ob_itfm); +#else + isect->t *= bvh_instance_push(kg, object, ray, &P, &dir, &idir); +#endif + + ++stack_ptr; + kernel_assert(stack_ptr < BVH_STACK_SIZE); + traversal_stack[stack_ptr] = ENTRYPOINT_SENTINEL; + + node_addr = kernel_tex_fetch(__object_node, object); + } + } + } while (node_addr != ENTRYPOINT_SENTINEL); + + 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 + + object = OBJECT_NONE; + node_addr = traversal_stack[stack_ptr]; + --stack_ptr; + } + } while (node_addr != ENTRYPOINT_SENTINEL); + + return (isect->prim != PRIM_NONE); +} + +ccl_device_inline bool BVH_FUNCTION_NAME(KernelGlobals kg, + ccl_private const Ray *ray, + ccl_private Intersection *isect, + const uint visibility) +{ + return BVH_FUNCTION_FULL_NAME(BVH)(kg, ray, isect, visibility); +} + +#undef BVH_FUNCTION_NAME +#undef BVH_FUNCTION_FEATURES +#undef NODE_INTERSECT |