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Diffstat (limited to 'intern/cycles/kernel/bvh/shadow_all.h')
| -rw-r--r-- | intern/cycles/kernel/bvh/shadow_all.h | 339 |
1 files changed, 339 insertions, 0 deletions
diff --git a/intern/cycles/kernel/bvh/shadow_all.h b/intern/cycles/kernel/bvh/shadow_all.h new file mode 100644 index 00000000000..049c6a03fe0 --- /dev/null +++ b/intern/cycles/kernel/bvh/shadow_all.h @@ -0,0 +1,339 @@ +/* + * 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 + */ + +#ifndef __KERNEL_GPU__ +ccl_device +#else +ccl_device_inline +#endif + bool BVH_FUNCTION_FULL_NAME(BVH)(KernelGlobals kg, + ccl_private const Ray *ray, + IntegratorShadowState state, + const uint visibility, + const uint max_hits, + ccl_private uint *num_recorded_hits, + ccl_private float *throughput) +{ + /* todo: + * - 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; + uint num_hits = 0; + +#if BVH_FEATURE(BVH_MOTION) + Transform ob_itfm; +#endif + + /* Max distance in world space. May be dynamically reduced when max number of + * recorded hits is exceeded and we no longer need to find hits beyond the max + * distance found. */ + float t_max_world = ray->t; + /* Equal to t_max_world when traversing top level BVH, transformed into local + * space when entering instances. */ + float t_max_current = t_max_world; + /* Conversion from world to local space for the current instance if any, 1.0 + * otherwise. */ + float t_world_to_instance = 1.0f; + + *num_recorded_hits = 0; + *throughput = 1.0f; + + /* 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, + t_max_current, + 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 */ + while (prim_addr < prim_addr2) { + kernel_assert((kernel_tex_fetch(__prim_type, prim_addr) & PRIMITIVE_ALL) == + (type & PRIMITIVE_ALL)); + bool hit; + + /* todo: specialized intersect functions which don't fill in + * isect unless needed and check SD_HAS_TRANSPARENT_SHADOW? + * might give a few % performance improvement */ + Intersection isect ccl_optional_struct_init; + + switch (type & PRIMITIVE_ALL) { + case PRIMITIVE_TRIANGLE: { + hit = triangle_intersect( + kg, &isect, P, dir, t_max_current, visibility, object, prim_addr); + break; + } +#if BVH_FEATURE(BVH_MOTION) + case PRIMITIVE_MOTION_TRIANGLE: { + hit = motion_triangle_intersect( + kg, &isect, P, dir, t_max_current, ray->time, visibility, object, prim_addr); + break; + } +#endif +#if BVH_FEATURE(BVH_HAIR) + case PRIMITIVE_CURVE_THICK: + case PRIMITIVE_MOTION_CURVE_THICK: + case PRIMITIVE_CURVE_RIBBON: + case PRIMITIVE_MOTION_CURVE_RIBBON: { + 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) { + hit = false; + break; + } + } + + const int curve_object = (object == OBJECT_NONE) ? + kernel_tex_fetch(__prim_object, prim_addr) : + object; + const int curve_type = kernel_tex_fetch(__prim_type, prim_addr); + const int curve_prim = kernel_tex_fetch(__prim_index, prim_addr); + hit = curve_intersect(kg, + &isect, + P, + dir, + t_max_current, + curve_object, + curve_prim, + ray->time, + curve_type); + + break; + } +#endif + default: { + hit = false; + break; + } + } + + /* shadow ray early termination */ + if (hit) { + /* Convert intersection distance to world space. */ + isect.t /= t_world_to_instance; + + /* detect if this surface has a shader with transparent shadows */ + /* todo: optimize so primitive visibility flag indicates if + * the primitive has a transparent shadow shader? */ + const int flags = intersection_get_shader_flags(kg, isect.prim, isect.type); + + if (!(flags & SD_HAS_TRANSPARENT_SHADOW) || num_hits >= max_hits) { + /* If no transparent shadows, all light is blocked and we can + * stop immediately. */ + return true; + } + + num_hits++; + + bool record_intersection = true; + + /* Always use baked shadow transparency for curves. */ + if (isect.type & PRIMITIVE_ALL_CURVE) { + *throughput *= intersection_curve_shadow_transparency( + kg, isect.object, isect.prim, isect.u); + + if (*throughput < CURVE_SHADOW_TRANSPARENCY_CUTOFF) { + return true; + } + else { + record_intersection = false; + } + } + + if (record_intersection) { + /* Increase the number of hits, possibly beyond max_hits, we will + * simply not record those and only keep the max_hits closest. */ + uint record_index = (*num_recorded_hits)++; + + const uint max_record_hits = min(max_hits, INTEGRATOR_SHADOW_ISECT_SIZE); + if (record_index >= max_record_hits - 1) { + /* If maximum number of hits reached, find the intersection with + * the largest distance to potentially replace when another hit + * is found. */ + const int num_recorded_hits = min(max_record_hits, record_index); + float max_recorded_t = INTEGRATOR_STATE_ARRAY(state, shadow_isect, 0, t); + int max_recorded_hit = 0; + + for (int i = 1; i < num_recorded_hits; i++) { + const float isect_t = INTEGRATOR_STATE_ARRAY(state, shadow_isect, i, t); + if (isect_t > max_recorded_t) { + max_recorded_t = isect_t; + max_recorded_hit = i; + } + } + + if (record_index >= max_record_hits) { + record_index = max_recorded_hit; + } + + /* Limit the ray distance and stop counting hits beyond this. */ + t_max_world = max(max_recorded_t, isect.t); + t_max_current = t_max_world * t_world_to_instance; + } + + integrator_state_write_shadow_isect(state, &isect, record_index); + } + } + + prim_addr++; + } + } + else { + /* instance push */ + object = kernel_tex_fetch(__prim_object, -prim_addr - 1); + +#if BVH_FEATURE(BVH_MOTION) + t_world_to_instance = bvh_instance_motion_push( + kg, object, ray, &P, &dir, &idir, &ob_itfm); +#else + t_world_to_instance = bvh_instance_push(kg, object, ray, &P, &dir, &idir); +#endif + + /* Convert intersection to object space. */ + t_max_current *= t_world_to_instance; + + ++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) + bvh_instance_motion_pop(kg, object, ray, &P, &dir, &idir, FLT_MAX, &ob_itfm); +#else + bvh_instance_pop(kg, object, ray, &P, &dir, &idir, FLT_MAX); +#endif + + /* Restore world space ray length. */ + t_max_current = t_max_world; + + object = OBJECT_NONE; + t_world_to_instance = 1.0f; + node_addr = traversal_stack[stack_ptr]; + --stack_ptr; + } + } while (node_addr != ENTRYPOINT_SENTINEL); + + return false; +} + +ccl_device_inline bool BVH_FUNCTION_NAME(KernelGlobals kg, + ccl_private const Ray *ray, + IntegratorShadowState state, + const uint visibility, + const uint max_hits, + ccl_private uint *num_recorded_hits, + ccl_private float *throughput) +{ + return BVH_FUNCTION_FULL_NAME(BVH)( + kg, ray, state, visibility, max_hits, num_recorded_hits, throughput); +} + +#undef BVH_FUNCTION_NAME +#undef BVH_FUNCTION_FEATURES +#undef NODE_INTERSECT |