diff options
author | Brecht Van Lommel <brecht@blender.org> | 2022-09-02 16:32:46 +0300 |
---|---|---|
committer | Brecht Van Lommel <brecht@blender.org> | 2022-09-02 18:13:28 +0300 |
commit | aa174f632e32695128e149e0559ac10e7f1d3f57 (patch) | |
tree | 00fc18f301ee5e6bfbc6dcd8b2573f125c87d126 /intern/cycles/kernel/integrator | |
parent | b8653398332f00754217421fa8f4f289c0ed147a (diff) |
Cleanup: split surface/displacement/volume shader eval into separate files
Diffstat (limited to 'intern/cycles/kernel/integrator')
-rw-r--r-- | intern/cycles/kernel/integrator/displacement_shader.h | 38 | ||||
-rw-r--r-- | intern/cycles/kernel/integrator/intersect_volume_stack.h | 1 | ||||
-rw-r--r-- | intern/cycles/kernel/integrator/mnee.h | 6 | ||||
-rw-r--r-- | intern/cycles/kernel/integrator/shade_background.h | 8 | ||||
-rw-r--r-- | intern/cycles/kernel/integrator/shade_light.h | 2 | ||||
-rw-r--r-- | intern/cycles/kernel/integrator/shade_shadow.h | 6 | ||||
-rw-r--r-- | intern/cycles/kernel/integrator/shade_surface.h | 24 | ||||
-rw-r--r-- | intern/cycles/kernel/integrator/shade_volume.h | 16 | ||||
-rw-r--r-- | intern/cycles/kernel/integrator/shader_eval.h | 947 | ||||
-rw-r--r-- | intern/cycles/kernel/integrator/subsurface.h | 6 | ||||
-rw-r--r-- | intern/cycles/kernel/integrator/surface_shader.h | 587 | ||||
-rw-r--r-- | intern/cycles/kernel/integrator/volume_shader.h | 353 |
12 files changed, 1013 insertions, 981 deletions
diff --git a/intern/cycles/kernel/integrator/displacement_shader.h b/intern/cycles/kernel/integrator/displacement_shader.h new file mode 100644 index 00000000000..71a0f56fb3e --- /dev/null +++ b/intern/cycles/kernel/integrator/displacement_shader.h @@ -0,0 +1,38 @@ +/* SPDX-License-Identifier: Apache-2.0 + * Copyright 2011-2022 Blender Foundation */ + +/* Functions to evaluate displacement shader. */ + +#pragma once + +#include "kernel/svm/svm.h" + +#ifdef __OSL__ +# include "kernel/osl/shader.h" +#endif + +CCL_NAMESPACE_BEGIN + +template<typename ConstIntegratorGenericState> +ccl_device void displacement_shader_eval(KernelGlobals kg, + ConstIntegratorGenericState state, + ccl_private ShaderData *sd) +{ + sd->num_closure = 0; + sd->num_closure_left = 0; + + /* this will modify sd->P */ +#ifdef __SVM__ +# ifdef __OSL__ + if (kg->osl) + OSLShader::eval_displacement(kg, state, sd); + else +# endif + { + svm_eval_nodes<KERNEL_FEATURE_NODE_MASK_DISPLACEMENT, SHADER_TYPE_DISPLACEMENT>( + kg, state, sd, NULL, 0); + } +#endif +} + +CCL_NAMESPACE_END diff --git a/intern/cycles/kernel/integrator/intersect_volume_stack.h b/intern/cycles/kernel/integrator/intersect_volume_stack.h index b53bee11312..c2490581e4d 100644 --- a/intern/cycles/kernel/integrator/intersect_volume_stack.h +++ b/intern/cycles/kernel/integrator/intersect_volume_stack.h @@ -5,7 +5,6 @@ #include "kernel/bvh/bvh.h" #include "kernel/geom/geom.h" -#include "kernel/integrator/shader_eval.h" #include "kernel/integrator/volume_stack.h" CCL_NAMESPACE_BEGIN diff --git a/intern/cycles/kernel/integrator/mnee.h b/intern/cycles/kernel/integrator/mnee.h index 84d527bc8b1..a0ad7afe591 100644 --- a/intern/cycles/kernel/integrator/mnee.h +++ b/intern/cycles/kernel/integrator/mnee.h @@ -807,7 +807,7 @@ ccl_device_forceinline bool mnee_path_contribution(KernelGlobals kg, float3 wo = normalize_len(vertices[0].p - sd->P, &wo_len); /* Initialize throughput and evaluate receiver bsdf * |n.wo|. */ - shader_bsdf_eval(kg, sd, wo, false, throughput, ls->shader); + surface_shader_bsdf_eval(kg, sd, wo, false, throughput, ls->shader); /* Update light sample with new position / direct.ion * and keep pdf in vertex area measure */ @@ -913,7 +913,7 @@ ccl_device_forceinline bool mnee_path_contribution(KernelGlobals kg, INTEGRATOR_STATE_WRITE(state, path, bounce) = bounce + 1 + vi; /* Evaluate shader nodes at solution vi. */ - shader_eval_surface<KERNEL_FEATURE_NODE_MASK_SURFACE_SHADOW>( + surface_shader_eval<KERNEL_FEATURE_NODE_MASK_SURFACE_SHADOW>( kg, state, sd_mnee, NULL, PATH_RAY_DIFFUSE, true); /* Set light looking dir. */ @@ -1006,7 +1006,7 @@ ccl_device_forceinline int kernel_path_mnee_sample(KernelGlobals kg, return 0; /* Last bool argument is the MNEE flag (for TINY_MAX_CLOSURE cap in kernel_shader.h). */ - shader_eval_surface<KERNEL_FEATURE_NODE_MASK_SURFACE_SHADOW>( + surface_shader_eval<KERNEL_FEATURE_NODE_MASK_SURFACE_SHADOW>( kg, state, sd_mnee, NULL, PATH_RAY_DIFFUSE, true); /* Get and sample refraction bsdf */ diff --git a/intern/cycles/kernel/integrator/shade_background.h b/intern/cycles/kernel/integrator/shade_background.h index a06791e6059..30ce0999258 100644 --- a/intern/cycles/kernel/integrator/shade_background.h +++ b/intern/cycles/kernel/integrator/shade_background.h @@ -5,7 +5,7 @@ #include "kernel/film/light_passes.h" -#include "kernel/integrator/shader_eval.h" +#include "kernel/integrator/surface_shader.h" #include "kernel/light/light.h" #include "kernel/light/sample.h" @@ -32,7 +32,7 @@ ccl_device Spectrum integrator_eval_background_shader(KernelGlobals kg, /* Use fast constant background color if available. */ Spectrum L = zero_spectrum(); - if (shader_constant_emission_eval(kg, shader, &L)) { + if (surface_shader_constant_emission(kg, shader, &L)) { return L; } @@ -52,10 +52,10 @@ ccl_device Spectrum integrator_eval_background_shader(KernelGlobals kg, PROFILING_SHADER(emission_sd->object, emission_sd->shader); PROFILING_EVENT(PROFILING_SHADE_LIGHT_EVAL); - shader_eval_surface<KERNEL_FEATURE_NODE_MASK_SURFACE_BACKGROUND>( + surface_shader_eval<KERNEL_FEATURE_NODE_MASK_SURFACE_BACKGROUND>( kg, state, emission_sd, render_buffer, path_flag | PATH_RAY_EMISSION); - return shader_background_eval(emission_sd); + return surface_shader_background(emission_sd); } ccl_device_inline void integrate_background(KernelGlobals kg, diff --git a/intern/cycles/kernel/integrator/shade_light.h b/intern/cycles/kernel/integrator/shade_light.h index d91fa2a2663..a4246f99bbf 100644 --- a/intern/cycles/kernel/integrator/shade_light.h +++ b/intern/cycles/kernel/integrator/shade_light.h @@ -4,7 +4,7 @@ #pragma once #include "kernel/film/light_passes.h" -#include "kernel/integrator/shader_eval.h" +#include "kernel/integrator/surface_shader.h" #include "kernel/light/light.h" #include "kernel/light/sample.h" diff --git a/intern/cycles/kernel/integrator/shade_shadow.h b/intern/cycles/kernel/integrator/shade_shadow.h index 074125bd200..ba18aed6ff0 100644 --- a/intern/cycles/kernel/integrator/shade_shadow.h +++ b/intern/cycles/kernel/integrator/shade_shadow.h @@ -4,7 +4,7 @@ #pragma once #include "kernel/integrator/shade_volume.h" -#include "kernel/integrator/shader_eval.h" +#include "kernel/integrator/surface_shader.h" #include "kernel/integrator/volume_stack.h" CCL_NAMESPACE_BEGIN @@ -40,7 +40,7 @@ ccl_device_inline Spectrum integrate_transparent_surface_shadow(KernelGlobals kg /* Evaluate shader. */ if (!(shadow_sd->flag & SD_HAS_ONLY_VOLUME)) { - shader_eval_surface<KERNEL_FEATURE_NODE_MASK_SURFACE_SHADOW>( + surface_shader_eval<KERNEL_FEATURE_NODE_MASK_SURFACE_SHADOW>( kg, state, shadow_sd, NULL, PATH_RAY_SHADOW); } @@ -50,7 +50,7 @@ ccl_device_inline Spectrum integrate_transparent_surface_shadow(KernelGlobals kg # endif /* Compute transparency from closures. */ - return shader_bsdf_transparency(kg, shadow_sd); + return surface_shader_transparency(kg, shadow_sd); } # ifdef __VOLUME__ diff --git a/intern/cycles/kernel/integrator/shade_surface.h b/intern/cycles/kernel/integrator/shade_surface.h index 013618ce0c1..c19f56a9b70 100644 --- a/intern/cycles/kernel/integrator/shade_surface.h +++ b/intern/cycles/kernel/integrator/shade_surface.h @@ -10,8 +10,8 @@ #include "kernel/integrator/mnee.h" #include "kernel/integrator/path_state.h" -#include "kernel/integrator/shader_eval.h" #include "kernel/integrator/subsurface.h" +#include "kernel/integrator/surface_shader.h" #include "kernel/integrator/volume_stack.h" #include "kernel/light/light.h" @@ -88,7 +88,7 @@ ccl_device_forceinline bool integrate_surface_holdout(KernelGlobals kg, if (((sd->flag & SD_HOLDOUT) || (sd->object_flag & SD_OBJECT_HOLDOUT_MASK)) && (path_flag & PATH_RAY_TRANSPARENT_BACKGROUND)) { - const Spectrum holdout_weight = shader_holdout_apply(kg, sd); + const Spectrum holdout_weight = surface_shader_apply_holdout(kg, sd); const Spectrum throughput = INTEGRATOR_STATE(state, path, throughput); const float transparent = average(holdout_weight * throughput); film_write_holdout(kg, state, path_flag, transparent, render_buffer); @@ -109,7 +109,7 @@ ccl_device_forceinline void integrate_surface_emission(KernelGlobals kg, const uint32_t path_flag = INTEGRATOR_STATE(state, path, flag); /* Evaluate emissive closure. */ - Spectrum L = shader_emissive_eval(sd); + Spectrum L = surface_shader_emission(sd); float mis_weight = 1.0f; #ifdef __HAIR__ @@ -171,7 +171,7 @@ ccl_device_forceinline void integrate_surface_direct_light(KernelGlobals kg, Ray ray ccl_optional_struct_init; BsdfEval bsdf_eval ccl_optional_struct_init; - const bool is_transmission = shader_bsdf_is_transmission(sd, ls.D); + const bool is_transmission = surface_shader_is_transmission(sd, ls.D); #ifdef __MNEE__ int mnee_vertex_count = 0; @@ -207,7 +207,8 @@ ccl_device_forceinline void integrate_surface_direct_light(KernelGlobals kg, } /* Evaluate BSDF. */ - const float bsdf_pdf = shader_bsdf_eval(kg, sd, ls.D, is_transmission, &bsdf_eval, ls.shader); + const float bsdf_pdf = surface_shader_bsdf_eval( + kg, sd, ls.D, is_transmission, &bsdf_eval, ls.shader); bsdf_eval_mul(&bsdf_eval, light_eval / ls.pdf); if (ls.shader & SHADER_USE_MIS) { @@ -341,7 +342,7 @@ ccl_device_forceinline int integrate_surface_bsdf_bssrdf_bounce( } float2 rand_bsdf = path_state_rng_2D(kg, rng_state, PRNG_SURFACE_BSDF); - ccl_private const ShaderClosure *sc = shader_bsdf_bssrdf_pick(sd, &rand_bsdf); + ccl_private const ShaderClosure *sc = surface_shader_bsdf_bssrdf_pick(sd, &rand_bsdf); #ifdef __SUBSURFACE__ /* BSSRDF closure, we schedule subsurface intersection kernel. */ @@ -356,7 +357,8 @@ ccl_device_forceinline int integrate_surface_bsdf_bssrdf_bounce( float3 bsdf_omega_in ccl_optional_struct_init; int label; - label = shader_bsdf_sample_closure(kg, sd, sc, rand_bsdf, &bsdf_eval, &bsdf_omega_in, &bsdf_pdf); + label = surface_shader_bsdf_sample_closure( + kg, sd, sc, rand_bsdf, &bsdf_eval, &bsdf_omega_in, &bsdf_pdf); if (bsdf_pdf == 0.0f || bsdf_eval_is_zero(&bsdf_eval)) { return LABEL_NONE; @@ -450,7 +452,7 @@ ccl_device_forceinline void integrate_surface_ao(KernelGlobals kg, const float2 rand_bsdf = path_state_rng_2D(kg, rng_state, PRNG_SURFACE_BSDF); float3 ao_N; - const Spectrum ao_weight = shader_bsdf_ao( + const Spectrum ao_weight = surface_shader_ao( kg, sd, kernel_data.integrator.ao_additive_factor, &ao_N); float3 ao_D; @@ -494,7 +496,7 @@ ccl_device_forceinline void integrate_surface_ao(KernelGlobals kg, const uint16_t transparent_bounce = INTEGRATOR_STATE(state, path, transparent_bounce); uint32_t shadow_flag = INTEGRATOR_STATE(state, path, flag) | PATH_RAY_SHADOW_FOR_AO; const Spectrum throughput = INTEGRATOR_STATE(state, path, throughput) * - shader_bsdf_alpha(kg, sd); + surface_shader_alpha(kg, sd); INTEGRATOR_STATE_WRITE(shadow_state, shadow_path, render_pixel_index) = INTEGRATOR_STATE( state, path, render_pixel_index); @@ -543,7 +545,7 @@ ccl_device bool integrate_surface(KernelGlobals kg, { /* Evaluate shader. */ PROFILING_EVENT(PROFILING_SHADE_SURFACE_EVAL); - shader_eval_surface<node_feature_mask>(kg, state, &sd, render_buffer, path_flag); + surface_shader_eval<node_feature_mask>(kg, state, &sd, render_buffer, path_flag); /* Initialize additional RNG for BSDFs. */ if (sd.flag & SD_BSDF_NEEDS_LCG) { @@ -565,7 +567,7 @@ ccl_device bool integrate_surface(KernelGlobals kg, #endif { /* Filter closures. */ - shader_prepare_surface_closures(kg, state, &sd, path_flag); + surface_shader_prepare_closures(kg, state, &sd, path_flag); /* Evaluate holdout. */ if (!integrate_surface_holdout(kg, state, &sd, render_buffer)) { diff --git a/intern/cycles/kernel/integrator/shade_volume.h b/intern/cycles/kernel/integrator/shade_volume.h index e2ccafbb384..aaef92729d6 100644 --- a/intern/cycles/kernel/integrator/shade_volume.h +++ b/intern/cycles/kernel/integrator/shade_volume.h @@ -9,7 +9,7 @@ #include "kernel/integrator/intersect_closest.h" #include "kernel/integrator/path_state.h" -#include "kernel/integrator/shader_eval.h" +#include "kernel/integrator/volume_shader.h" #include "kernel/integrator/volume_stack.h" #include "kernel/light/light.h" @@ -65,7 +65,7 @@ ccl_device_inline bool shadow_volume_shader_sample(KernelGlobals kg, ccl_private Spectrum *ccl_restrict extinction) { VOLUME_READ_LAMBDA(integrator_state_read_shadow_volume_stack(state, i)) - shader_eval_volume<true>(kg, state, sd, PATH_RAY_SHADOW, volume_read_lambda_pass); + volume_shader_eval<true>(kg, state, sd, PATH_RAY_SHADOW, volume_read_lambda_pass); if (!(sd->flag & SD_EXTINCTION)) { return false; @@ -84,7 +84,7 @@ ccl_device_inline bool volume_shader_sample(KernelGlobals kg, { const uint32_t path_flag = INTEGRATOR_STATE(state, path, flag); VOLUME_READ_LAMBDA(integrator_state_read_volume_stack(state, i)) - shader_eval_volume<false>(kg, state, sd, path_flag, volume_read_lambda_pass); + volume_shader_eval<false>(kg, state, sd, path_flag, volume_read_lambda_pass); if (!(sd->flag & (SD_EXTINCTION | SD_SCATTER | SD_EMISSION))) { return false; @@ -443,7 +443,7 @@ ccl_device_forceinline void volume_integrate_step_scattering( result.direct_scatter = true; result.direct_throughput *= coeff.sigma_s * new_transmittance / vstate.equiangular_pdf; - shader_copy_volume_phases(&result.direct_phases, sd); + volume_shader_copy_phases(&result.direct_phases, sd); /* Multiple importance sampling. */ if (vstate.use_mis) { @@ -479,7 +479,7 @@ ccl_device_forceinline void volume_integrate_step_scattering( result.indirect_scatter = true; result.indirect_t = new_t; result.indirect_throughput *= coeff.sigma_s * new_transmittance / distance_pdf; - shader_copy_volume_phases(&result.indirect_phases, sd); + volume_shader_copy_phases(&result.indirect_phases, sd); if (vstate.direct_sample_method != VOLUME_SAMPLE_EQUIANGULAR) { /* If using distance sampling for direct light, just copy parameters @@ -487,7 +487,7 @@ ccl_device_forceinline void volume_integrate_step_scattering( result.direct_scatter = true; result.direct_t = result.indirect_t; result.direct_throughput = result.indirect_throughput; - shader_copy_volume_phases(&result.direct_phases, sd); + volume_shader_copy_phases(&result.direct_phases, sd); /* Multiple importance sampling. */ if (vstate.use_mis) { @@ -761,7 +761,7 @@ ccl_device_forceinline void integrate_volume_direct_light( /* Evaluate BSDF. */ BsdfEval phase_eval ccl_optional_struct_init; - const float phase_pdf = shader_volume_phase_eval(kg, sd, phases, ls->D, &phase_eval); + const float phase_pdf = volume_shader_phase_eval(kg, sd, phases, ls->D, &phase_eval); if (ls->shader & SHADER_USE_MIS) { float mis_weight = light_sample_mis_weight_nee(kg, ls->pdf, phase_pdf); @@ -868,7 +868,7 @@ ccl_device_forceinline bool integrate_volume_phase_scatter( BsdfEval phase_eval ccl_optional_struct_init; float3 phase_omega_in ccl_optional_struct_init; - const int label = shader_volume_phase_sample( + const int label = volume_shader_phase_sample( kg, sd, phases, rand_phase, &phase_eval, &phase_omega_in, &phase_pdf); if (phase_pdf == 0.0f || bsdf_eval_is_zero(&phase_eval)) { diff --git a/intern/cycles/kernel/integrator/shader_eval.h b/intern/cycles/kernel/integrator/shader_eval.h deleted file mode 100644 index 11ecf60d00d..00000000000 --- a/intern/cycles/kernel/integrator/shader_eval.h +++ /dev/null @@ -1,947 +0,0 @@ -/* SPDX-License-Identifier: Apache-2.0 - * Copyright 2011-2022 Blender Foundation */ - -/* Functions to evaluate shaders and use the resulting shader closures. */ - -#pragma once - -#include "kernel/closure/alloc.h" -#include "kernel/closure/bsdf.h" -#include "kernel/closure/bsdf_util.h" -#include "kernel/closure/emissive.h" - -#include "kernel/film/light_passes.h" - -#include "kernel/svm/svm.h" - -#ifdef __OSL__ -# include "kernel/osl/shader.h" -#endif - -CCL_NAMESPACE_BEGIN - -/* Merging */ - -#if defined(__VOLUME__) -ccl_device_inline void shader_merge_volume_closures(ccl_private ShaderData *sd) -{ - /* Merge identical closures to save closure space with stacked volumes. */ - for (int i = 0; i < sd->num_closure; i++) { - ccl_private ShaderClosure *sci = &sd->closure[i]; - - if (sci->type != CLOSURE_VOLUME_HENYEY_GREENSTEIN_ID) { - continue; - } - - for (int j = i + 1; j < sd->num_closure; j++) { - ccl_private ShaderClosure *scj = &sd->closure[j]; - if (sci->type != scj->type) { - continue; - } - - ccl_private const HenyeyGreensteinVolume *hgi = (ccl_private const HenyeyGreensteinVolume *) - sci; - ccl_private const HenyeyGreensteinVolume *hgj = (ccl_private const HenyeyGreensteinVolume *) - scj; - if (!(hgi->g == hgj->g)) { - continue; - } - - sci->weight += scj->weight; - sci->sample_weight += scj->sample_weight; - - int size = sd->num_closure - (j + 1); - if (size > 0) { - for (int k = 0; k < size; k++) { - scj[k] = scj[k + 1]; - } - } - - sd->num_closure--; - kernel_assert(sd->num_closure >= 0); - j--; - } - } -} - -ccl_device_inline void shader_copy_volume_phases(ccl_private ShaderVolumePhases *ccl_restrict - phases, - ccl_private const ShaderData *ccl_restrict sd) -{ - phases->num_closure = 0; - - for (int i = 0; i < sd->num_closure; i++) { - ccl_private const ShaderClosure *from_sc = &sd->closure[i]; - ccl_private const HenyeyGreensteinVolume *from_hg = - (ccl_private const HenyeyGreensteinVolume *)from_sc; - - if (from_sc->type == CLOSURE_VOLUME_HENYEY_GREENSTEIN_ID) { - ccl_private ShaderVolumeClosure *to_sc = &phases->closure[phases->num_closure]; - - to_sc->weight = from_sc->weight; - to_sc->sample_weight = from_sc->sample_weight; - to_sc->g = from_hg->g; - phases->num_closure++; - if (phases->num_closure >= MAX_VOLUME_CLOSURE) { - break; - } - } - } -} -#endif /* __VOLUME__ */ - -ccl_device_inline void shader_prepare_surface_closures(KernelGlobals kg, - ConstIntegratorState state, - ccl_private ShaderData *sd, - const uint32_t path_flag) -{ - /* Filter out closures. */ - if (kernel_data.integrator.filter_closures) { - if (kernel_data.integrator.filter_closures & FILTER_CLOSURE_EMISSION) { - sd->closure_emission_background = zero_spectrum(); - } - - if (kernel_data.integrator.filter_closures & FILTER_CLOSURE_DIRECT_LIGHT) { - sd->flag &= ~SD_BSDF_HAS_EVAL; - } - - if (path_flag & PATH_RAY_CAMERA) { - for (int i = 0; i < sd->num_closure; i++) { - ccl_private ShaderClosure *sc = &sd->closure[i]; - - if ((CLOSURE_IS_BSDF_DIFFUSE(sc->type) && - (kernel_data.integrator.filter_closures & FILTER_CLOSURE_DIFFUSE)) || - (CLOSURE_IS_BSDF_GLOSSY(sc->type) && - (kernel_data.integrator.filter_closures & FILTER_CLOSURE_GLOSSY)) || - (CLOSURE_IS_BSDF_TRANSMISSION(sc->type) && - (kernel_data.integrator.filter_closures & FILTER_CLOSURE_TRANSMISSION))) { - sc->type = CLOSURE_NONE_ID; - sc->sample_weight = 0.0f; - } - else if ((CLOSURE_IS_BSDF_TRANSPARENT(sc->type) && - (kernel_data.integrator.filter_closures & FILTER_CLOSURE_TRANSPARENT))) { - sc->type = CLOSURE_HOLDOUT_ID; - sc->sample_weight = 0.0f; - sd->flag |= SD_HOLDOUT; - } - } - } - } - - /* Defensive sampling. - * - * We can likely also do defensive sampling at deeper bounces, particularly - * for cases like a perfect mirror but possibly also others. This will need - * a good heuristic. */ - if (INTEGRATOR_STATE(state, path, bounce) + INTEGRATOR_STATE(state, path, transparent_bounce) == - 0 && - sd->num_closure > 1) { - float sum = 0.0f; - - for (int i = 0; i < sd->num_closure; i++) { - ccl_private ShaderClosure *sc = &sd->closure[i]; - if (CLOSURE_IS_BSDF_OR_BSSRDF(sc->type)) { - sum += sc->sample_weight; - } - } - - for (int i = 0; i < sd->num_closure; i++) { - ccl_private ShaderClosure *sc = &sd->closure[i]; - if (CLOSURE_IS_BSDF_OR_BSSRDF(sc->type)) { - sc->sample_weight = max(sc->sample_weight, 0.125f * sum); - } - } - } - - /* Filter glossy. - * - * Blurring of bsdf after bounces, for rays that have a small likelihood - * of following this particular path (diffuse, rough glossy) */ - if (kernel_data.integrator.filter_glossy != FLT_MAX -#ifdef __MNEE__ - && !(INTEGRATOR_STATE(state, path, mnee) & PATH_MNEE_VALID) -#endif - ) { - float blur_pdf = kernel_data.integrator.filter_glossy * - INTEGRATOR_STATE(state, path, min_ray_pdf); - - if (blur_pdf < 1.0f) { - float blur_roughness = sqrtf(1.0f - blur_pdf) * 0.5f; - - for (int i = 0; i < sd->num_closure; i++) { - ccl_private ShaderClosure *sc = &sd->closure[i]; - if (CLOSURE_IS_BSDF(sc->type)) { - bsdf_blur(kg, sc, blur_roughness); - } - } - } - } -} - -/* BSDF */ - -ccl_device_inline bool shader_bsdf_is_transmission(ccl_private const ShaderData *sd, - const float3 omega_in) -{ - return dot(sd->N, omega_in) < 0.0f; -} - -ccl_device_forceinline bool _shader_bsdf_exclude(ClosureType type, uint light_shader_flags) -{ - if (!(light_shader_flags & SHADER_EXCLUDE_ANY)) { - return false; - } - if (light_shader_flags & SHADER_EXCLUDE_DIFFUSE) { - if (CLOSURE_IS_BSDF_DIFFUSE(type)) { - return true; - } - } - if (light_shader_flags & SHADER_EXCLUDE_GLOSSY) { - if (CLOSURE_IS_BSDF_GLOSSY(type)) { - return true; - } - } - if (light_shader_flags & SHADER_EXCLUDE_TRANSMIT) { - if (CLOSURE_IS_BSDF_TRANSMISSION(type)) { - return true; - } - } - return false; -} - -ccl_device_inline float _shader_bsdf_multi_eval(KernelGlobals kg, - ccl_private ShaderData *sd, - const float3 omega_in, - const bool is_transmission, - ccl_private const ShaderClosure *skip_sc, - ccl_private BsdfEval *result_eval, - float sum_pdf, - float sum_sample_weight, - const uint light_shader_flags) -{ - /* This is the veach one-sample model with balance heuristic, - * some PDF factors drop out when using balance heuristic weighting. */ - for (int i = 0; i < sd->num_closure; i++) { - ccl_private const ShaderClosure *sc = &sd->closure[i]; - - if (sc == skip_sc) { - continue; - } - - if (CLOSURE_IS_BSDF_OR_BSSRDF(sc->type)) { - if (CLOSURE_IS_BSDF(sc->type) && !_shader_bsdf_exclude(sc->type, light_shader_flags)) { - float bsdf_pdf = 0.0f; - Spectrum eval = bsdf_eval(kg, sd, sc, omega_in, is_transmission, &bsdf_pdf); - - if (bsdf_pdf != 0.0f) { - bsdf_eval_accum(result_eval, sc->type, eval * sc->weight); - sum_pdf += bsdf_pdf * sc->sample_weight; - } - } - - sum_sample_weight += sc->sample_weight; - } - } - - return (sum_sample_weight > 0.0f) ? sum_pdf / sum_sample_weight : 0.0f; -} - -#ifndef __KERNEL_CUDA__ -ccl_device -#else -ccl_device_inline -#endif - float - shader_bsdf_eval(KernelGlobals kg, - ccl_private ShaderData *sd, - const float3 omega_in, - const bool is_transmission, - ccl_private BsdfEval *bsdf_eval, - const uint light_shader_flags) -{ - bsdf_eval_init(bsdf_eval, CLOSURE_NONE_ID, zero_spectrum()); - - return _shader_bsdf_multi_eval( - kg, sd, omega_in, is_transmission, NULL, bsdf_eval, 0.0f, 0.0f, light_shader_flags); -} - -/* Randomly sample a BSSRDF or BSDF proportional to ShaderClosure.sample_weight. */ -ccl_device_inline ccl_private const ShaderClosure *shader_bsdf_bssrdf_pick( - ccl_private const ShaderData *ccl_restrict sd, ccl_private float2 *rand_bsdf) -{ - int sampled = 0; - - if (sd->num_closure > 1) { - /* Pick a BSDF or based on sample weights. */ - float sum = 0.0f; - - for (int i = 0; i < sd->num_closure; i++) { - ccl_private const ShaderClosure *sc = &sd->closure[i]; - - if (CLOSURE_IS_BSDF_OR_BSSRDF(sc->type)) { - sum += sc->sample_weight; - } - } - - float r = (*rand_bsdf).x * sum; - float partial_sum = 0.0f; - - for (int i = 0; i < sd->num_closure; i++) { - ccl_private const ShaderClosure *sc = &sd->closure[i]; - - if (CLOSURE_IS_BSDF_OR_BSSRDF(sc->type)) { - float next_sum = partial_sum + sc->sample_weight; - - if (r < next_sum) { - sampled = i; - - /* Rescale to reuse for direction sample, to better preserve stratification. */ - (*rand_bsdf).x = (r - partial_sum) / sc->sample_weight; - break; - } - - partial_sum = next_sum; - } - } - } - - return &sd->closure[sampled]; -} - -/* Return weight for picked BSSRDF. */ -ccl_device_inline Spectrum -shader_bssrdf_sample_weight(ccl_private const ShaderData *ccl_restrict sd, - ccl_private const ShaderClosure *ccl_restrict bssrdf_sc) -{ - Spectrum weight = bssrdf_sc->weight; - - if (sd->num_closure > 1) { - float sum = 0.0f; - for (int i = 0; i < sd->num_closure; i++) { - ccl_private const ShaderClosure *sc = &sd->closure[i]; - - if (CLOSURE_IS_BSDF_OR_BSSRDF(sc->type)) { - sum += sc->sample_weight; - } - } - weight *= sum / bssrdf_sc->sample_weight; - } - - return weight; -} - -/* Sample direction for picked BSDF, and return evaluation and pdf for all - * BSDFs combined using MIS. */ -ccl_device int shader_bsdf_sample_closure(KernelGlobals kg, - ccl_private ShaderData *sd, - ccl_private const ShaderClosure *sc, - const float2 rand_bsdf, - ccl_private BsdfEval *bsdf_eval, - ccl_private float3 *omega_in, - ccl_private float *pdf) -{ - /* BSSRDF should already have been handled elsewhere. */ - kernel_assert(CLOSURE_IS_BSDF(sc->type)); - - int label; - Spectrum eval = zero_spectrum(); - - *pdf = 0.0f; - label = bsdf_sample(kg, sd, sc, rand_bsdf.x, rand_bsdf.y, &eval, omega_in, pdf); - - if (*pdf != 0.0f) { - bsdf_eval_init(bsdf_eval, sc->type, eval * sc->weight); - - if (sd->num_closure > 1) { - const bool is_transmission = shader_bsdf_is_transmission(sd, *omega_in); - float sweight = sc->sample_weight; - *pdf = _shader_bsdf_multi_eval( - kg, sd, *omega_in, is_transmission, sc, bsdf_eval, *pdf * sweight, sweight, 0); - } - } - - return label; -} - -ccl_device float shader_bsdf_average_roughness(ccl_private const ShaderData *sd) -{ - float roughness = 0.0f; - float sum_weight = 0.0f; - - for (int i = 0; i < sd->num_closure; i++) { - ccl_private const ShaderClosure *sc = &sd->closure[i]; - - if (CLOSURE_IS_BSDF(sc->type)) { - /* sqrt once to undo the squaring from multiplying roughness on the - * two axes, and once for the squared roughness convention. */ - float weight = fabsf(average(sc->weight)); - roughness += weight * sqrtf(safe_sqrtf(bsdf_get_roughness_squared(sc))); - sum_weight += weight; - } - } - - return (sum_weight > 0.0f) ? roughness / sum_weight : 0.0f; -} - -ccl_device Spectrum shader_bsdf_transparency(KernelGlobals kg, ccl_private const ShaderData *sd) -{ - if (sd->flag & SD_HAS_ONLY_VOLUME) { - return one_spectrum(); - } - else if (sd->flag & SD_TRANSPARENT) { - return sd->closure_transparent_extinction; - } - else { - return zero_spectrum(); - } -} - -ccl_device void shader_bsdf_disable_transparency(KernelGlobals kg, ccl_private ShaderData *sd) -{ - if (sd->flag & SD_TRANSPARENT) { - for (int i = 0; i < sd->num_closure; i++) { - ccl_private ShaderClosure *sc = &sd->closure[i]; - - if (sc->type == CLOSURE_BSDF_TRANSPARENT_ID) { - sc->sample_weight = 0.0f; - sc->weight = zero_spectrum(); - } - } - - sd->flag &= ~SD_TRANSPARENT; - } -} - -ccl_device Spectrum shader_bsdf_alpha(KernelGlobals kg, ccl_private const ShaderData *sd) -{ - Spectrum alpha = one_spectrum() - shader_bsdf_transparency(kg, sd); - - alpha = saturate(alpha); - - return alpha; -} - -ccl_device Spectrum shader_bsdf_diffuse(KernelGlobals kg, ccl_private const ShaderData *sd) -{ - Spectrum eval = zero_spectrum(); - - for (int i = 0; i < sd->num_closure; i++) { - ccl_private const ShaderClosure *sc = &sd->closure[i]; - - if (CLOSURE_IS_BSDF_DIFFUSE(sc->type) || CLOSURE_IS_BSSRDF(sc->type)) - eval += sc->weight; - } - - return eval; -} - -ccl_device Spectrum shader_bsdf_glossy(KernelGlobals kg, ccl_private const ShaderData *sd) -{ - Spectrum eval = zero_spectrum(); - - for (int i = 0; i < sd->num_closure; i++) { - ccl_private const ShaderClosure *sc = &sd->closure[i]; - - if (CLOSURE_IS_BSDF_GLOSSY(sc->type)) - eval += sc->weight; - } - - return eval; -} - -ccl_device Spectrum shader_bsdf_transmission(KernelGlobals kg, ccl_private const ShaderData *sd) -{ - Spectrum eval = zero_spectrum(); - - for (int i = 0; i < sd->num_closure; i++) { - ccl_private const ShaderClosure *sc = &sd->closure[i]; - - if (CLOSURE_IS_BSDF_TRANSMISSION(sc->type)) - eval += sc->weight; - } - - return eval; -} - -ccl_device float3 shader_bsdf_average_normal(KernelGlobals kg, ccl_private const ShaderData *sd) -{ - float3 N = zero_float3(); - - for (int i = 0; i < sd->num_closure; i++) { - ccl_private const ShaderClosure *sc = &sd->closure[i]; - if (CLOSURE_IS_BSDF_OR_BSSRDF(sc->type)) - N += sc->N * fabsf(average(sc->weight)); - } - - return (is_zero(N)) ? sd->N : normalize(N); -} - -ccl_device Spectrum shader_bsdf_ao(KernelGlobals kg, - ccl_private const ShaderData *sd, - const float ao_factor, - ccl_private float3 *N_) -{ - Spectrum eval = zero_spectrum(); - float3 N = zero_float3(); - - for (int i = 0; i < sd->num_closure; i++) { - ccl_private const ShaderClosure *sc = &sd->closure[i]; - - if (CLOSURE_IS_BSDF_DIFFUSE(sc->type)) { - ccl_private const DiffuseBsdf *bsdf = (ccl_private const DiffuseBsdf *)sc; - eval += sc->weight * ao_factor; - N += bsdf->N * fabsf(average(sc->weight)); - } - } - - *N_ = (is_zero(N)) ? sd->N : normalize(N); - return eval; -} - -#ifdef __SUBSURFACE__ -ccl_device float3 shader_bssrdf_normal(ccl_private const ShaderData *sd) -{ - float3 N = zero_float3(); - - for (int i = 0; i < sd->num_closure; i++) { - ccl_private const ShaderClosure *sc = &sd->closure[i]; - - if (CLOSURE_IS_BSSRDF(sc->type)) { - ccl_private const Bssrdf *bssrdf = (ccl_private const Bssrdf *)sc; - float avg_weight = fabsf(average(sc->weight)); - - N += bssrdf->N * avg_weight; - } - } - - return (is_zero(N)) ? sd->N : normalize(N); -} -#endif /* __SUBSURFACE__ */ - -/* Constant emission optimization */ - -ccl_device bool shader_constant_emission_eval(KernelGlobals kg, - int shader, - ccl_private Spectrum *eval) -{ - int shader_index = shader & SHADER_MASK; - int shader_flag = kernel_data_fetch(shaders, shader_index).flags; - - if (shader_flag & SD_HAS_CONSTANT_EMISSION) { - const float3 emission_rgb = make_float3( - kernel_data_fetch(shaders, shader_index).constant_emission[0], - kernel_data_fetch(shaders, shader_index).constant_emission[1], - kernel_data_fetch(shaders, shader_index).constant_emission[2]); - *eval = rgb_to_spectrum(emission_rgb); - - return true; - } - - return false; -} - -/* Background */ - -ccl_device Spectrum shader_background_eval(ccl_private const ShaderData *sd) -{ - if (sd->flag & SD_EMISSION) { - return sd->closure_emission_background; - } - else { - return zero_spectrum(); - } -} - -/* Emission */ - -ccl_device Spectrum shader_emissive_eval(ccl_private const ShaderData *sd) -{ - if (sd->flag & SD_EMISSION) { - return emissive_simple_eval(sd->Ng, sd->I) * sd->closure_emission_background; - } - else { - return zero_spectrum(); - } -} - -/* Holdout */ - -ccl_device Spectrum shader_holdout_apply(KernelGlobals kg, ccl_private ShaderData *sd) -{ - Spectrum weight = zero_spectrum(); - - /* For objects marked as holdout, preserve transparency and remove all other - * closures, replacing them with a holdout weight. */ - if (sd->object_flag & SD_OBJECT_HOLDOUT_MASK) { - if ((sd->flag & SD_TRANSPARENT) && !(sd->flag & SD_HAS_ONLY_VOLUME)) { - weight = one_spectrum() - sd->closure_transparent_extinction; - - for (int i = 0; i < sd->num_closure; i++) { - ccl_private ShaderClosure *sc = &sd->closure[i]; - if (!CLOSURE_IS_BSDF_TRANSPARENT(sc->type)) { - sc->type = NBUILTIN_CLOSURES; - } - } - - sd->flag &= ~(SD_CLOSURE_FLAGS - (SD_TRANSPARENT | SD_BSDF)); - } - else { - weight = one_spectrum(); - } - } - else { - for (int i = 0; i < sd->num_closure; i++) { - ccl_private const ShaderClosure *sc = &sd->closure[i]; - if (CLOSURE_IS_HOLDOUT(sc->type)) { - weight += sc->weight; - } - } - } - - return weight; -} - -/* Surface Evaluation */ - -template<uint node_feature_mask, typename ConstIntegratorGenericState> -ccl_device void shader_eval_surface(KernelGlobals kg, - ConstIntegratorGenericState state, - ccl_private ShaderData *ccl_restrict sd, - ccl_global float *ccl_restrict buffer, - uint32_t path_flag, - bool use_caustics_storage = false) -{ - /* If path is being terminated, we are tracing a shadow ray or evaluating - * emission, then we don't need to store closures. The emission and shadow - * shader data also do not have a closure array to save GPU memory. */ - int max_closures; - if (path_flag & (PATH_RAY_TERMINATE | PATH_RAY_SHADOW | PATH_RAY_EMISSION)) { - max_closures = 0; - } - else { - max_closures = use_caustics_storage ? CAUSTICS_MAX_CLOSURE : kernel_data.max_closures; - } - - sd->num_closure = 0; - sd->num_closure_left = max_closures; - -#ifdef __OSL__ - if (kg->osl) { - if (sd->object == OBJECT_NONE && sd->lamp == LAMP_NONE) { - OSLShader::eval_background(kg, state, sd, path_flag); - } - else { - OSLShader::eval_surface(kg, state, sd, path_flag); - } - } - else -#endif - { -#ifdef __SVM__ - svm_eval_nodes<node_feature_mask, SHADER_TYPE_SURFACE>(kg, state, sd, buffer, path_flag); -#else - if (sd->object == OBJECT_NONE) { - sd->closure_emission_background = make_spectrum(0.8f); - sd->flag |= SD_EMISSION; - } - else { - ccl_private DiffuseBsdf *bsdf = (ccl_private DiffuseBsdf *)bsdf_alloc( - sd, sizeof(DiffuseBsdf), make_spectrum(0.8f)); - if (bsdf != NULL) { - bsdf->N = sd->N; - sd->flag |= bsdf_diffuse_setup(bsdf); - } - } -#endif - } -} - -/* Volume */ - -#ifdef __VOLUME__ - -ccl_device_inline float _shader_volume_phase_multi_eval( - ccl_private const ShaderData *sd, - ccl_private const ShaderVolumePhases *phases, - const float3 omega_in, - int skip_phase, - ccl_private BsdfEval *result_eval, - float sum_pdf, - float sum_sample_weight) -{ - for (int i = 0; i < phases->num_closure; i++) { - if (i == skip_phase) - continue; - - ccl_private const ShaderVolumeClosure *svc = &phases->closure[i]; - float phase_pdf = 0.0f; - Spectrum eval = volume_phase_eval(sd, svc, omega_in, &phase_pdf); - - if (phase_pdf != 0.0f) { - bsdf_eval_accum(result_eval, CLOSURE_VOLUME_HENYEY_GREENSTEIN_ID, eval); - sum_pdf += phase_pdf * svc->sample_weight; - } - - sum_sample_weight += svc->sample_weight; - } - - return (sum_sample_weight > 0.0f) ? sum_pdf / sum_sample_weight : 0.0f; -} - -ccl_device float shader_volume_phase_eval(KernelGlobals kg, - ccl_private const ShaderData *sd, - ccl_private const ShaderVolumePhases *phases, - const float3 omega_in, - ccl_private BsdfEval *phase_eval) -{ - bsdf_eval_init(phase_eval, CLOSURE_VOLUME_HENYEY_GREENSTEIN_ID, zero_spectrum()); - - return _shader_volume_phase_multi_eval(sd, phases, omega_in, -1, phase_eval, 0.0f, 0.0f); -} - -ccl_device int shader_volume_phase_sample(KernelGlobals kg, - ccl_private const ShaderData *sd, - ccl_private const ShaderVolumePhases *phases, - float2 rand_phase, - ccl_private BsdfEval *phase_eval, - ccl_private float3 *omega_in, - ccl_private float *pdf) -{ - int sampled = 0; - - if (phases->num_closure > 1) { - /* pick a phase closure based on sample weights */ - float sum = 0.0f; - - for (sampled = 0; sampled < phases->num_closure; sampled++) { - ccl_private const ShaderVolumeClosure *svc = &phases->closure[sampled]; - sum += svc->sample_weight; - } - - float r = rand_phase.x * sum; - float partial_sum = 0.0f; - - for (sampled = 0; sampled < phases->num_closure; sampled++) { - ccl_private const ShaderVolumeClosure *svc = &phases->closure[sampled]; - float next_sum = partial_sum + svc->sample_weight; - - if (r <= next_sum) { - /* Rescale to reuse for BSDF direction sample. */ - rand_phase.x = (r - partial_sum) / svc->sample_weight; - break; - } - - partial_sum = next_sum; - } - - if (sampled == phases->num_closure) { - *pdf = 0.0f; - return LABEL_NONE; - } - } - - /* todo: this isn't quite correct, we don't weight anisotropy properly - * depending on color channels, even if this is perhaps not a common case */ - ccl_private const ShaderVolumeClosure *svc = &phases->closure[sampled]; - int label; - Spectrum eval = zero_spectrum(); - - *pdf = 0.0f; - label = volume_phase_sample(sd, svc, rand_phase.x, rand_phase.y, &eval, omega_in, pdf); - - if (*pdf != 0.0f) { - bsdf_eval_init(phase_eval, CLOSURE_VOLUME_HENYEY_GREENSTEIN_ID, eval); - } - - return label; -} - -ccl_device int shader_phase_sample_closure(KernelGlobals kg, - ccl_private const ShaderData *sd, - ccl_private const ShaderVolumeClosure *sc, - const float2 rand_phase, - ccl_private BsdfEval *phase_eval, - ccl_private float3 *omega_in, - ccl_private float *pdf) -{ - int label; - Spectrum eval = zero_spectrum(); - - *pdf = 0.0f; - label = volume_phase_sample(sd, sc, rand_phase.x, rand_phase.y, &eval, omega_in, pdf); - - if (*pdf != 0.0f) - bsdf_eval_init(phase_eval, CLOSURE_VOLUME_HENYEY_GREENSTEIN_ID, eval); - - return label; -} - -/* Volume Evaluation */ - -template<const bool shadow, typename StackReadOp, typename ConstIntegratorGenericState> -ccl_device_inline void shader_eval_volume(KernelGlobals kg, - ConstIntegratorGenericState state, - ccl_private ShaderData *ccl_restrict sd, - const uint32_t path_flag, - StackReadOp stack_read) -{ - /* If path is being terminated, we are tracing a shadow ray or evaluating - * emission, then we don't need to store closures. The emission and shadow - * shader data also do not have a closure array to save GPU memory. */ - int max_closures; - if (path_flag & (PATH_RAY_TERMINATE | PATH_RAY_SHADOW | PATH_RAY_EMISSION)) { - max_closures = 0; - } - else { - max_closures = kernel_data.max_closures; - } - - /* reset closures once at the start, we will be accumulating the closures - * for all volumes in the stack into a single array of closures */ - sd->num_closure = 0; - sd->num_closure_left = max_closures; - sd->flag = 0; - sd->object_flag = 0; - - for (int i = 0;; i++) { - const VolumeStack entry = stack_read(i); - if (entry.shader == SHADER_NONE) { - break; - } - - /* Setup shader-data from stack. it's mostly setup already in - * shader_setup_from_volume, this switching should be quick. */ - sd->object = entry.object; - sd->lamp = LAMP_NONE; - sd->shader = entry.shader; - - sd->flag &= ~SD_SHADER_FLAGS; - sd->flag |= kernel_data_fetch(shaders, (sd->shader & SHADER_MASK)).flags; - sd->object_flag &= ~SD_OBJECT_FLAGS; - - if (sd->object != OBJECT_NONE) { - sd->object_flag |= kernel_data_fetch(object_flag, sd->object); - -# ifdef __OBJECT_MOTION__ - /* todo: this is inefficient for motion blur, we should be - * caching matrices instead of recomputing them each step */ - shader_setup_object_transforms(kg, sd, sd->time); - - if ((sd->object_flag & SD_OBJECT_HAS_VOLUME_MOTION) != 0) { - AttributeDescriptor v_desc = find_attribute(kg, sd, ATTR_STD_VOLUME_VELOCITY); - kernel_assert(v_desc.offset != ATTR_STD_NOT_FOUND); - - const float3 P = sd->P; - const float velocity_scale = kernel_data_fetch(objects, sd->object).velocity_scale; - const float time_offset = kernel_data.cam.motion_position == MOTION_POSITION_CENTER ? - 0.5f : - 0.0f; - const float time = kernel_data.cam.motion_position == MOTION_POSITION_END ? - (1.0f - kernel_data.cam.shuttertime) + sd->time : - sd->time; - - /* Use a 1st order semi-lagrangian advection scheme to estimate what volume quantity - * existed, or will exist, at the given time: - * - * `phi(x, T) = phi(x - (T - t) * u(x, T), t)` - * - * where - * - * x : position - * T : super-sampled time (or ray time) - * t : current time of the simulation (in rendering we assume this is center frame with - * relative time = 0) - * phi : the volume quantity - * u : the velocity field - * - * But first we need to determine the velocity field `u(x, T)`, which we can estimate also - * using semi-lagrangian advection. - * - * `u(x, T) = u(x - (T - t) * u(x, T), t)` - * - * This is the typical way to model self-advection in fluid dynamics, however, we do not - * account for other forces affecting the velocity during simulation (pressure, buoyancy, - * etc.): this gives a linear interpolation when fluid are mostly "curvy". For better - * results, a higher order interpolation scheme can be used (at the cost of more lookups), - * or an interpolation of the velocity fields for the previous and next frames could also - * be used to estimate `u(x, T)` (which will cost more memory and lookups). - * - * References: - * "Eulerian Motion Blur", Kim and Ko, 2007 - * "Production Volume Rendering", Wreninge et al., 2012 - */ - - /* Find velocity. */ - float3 velocity = primitive_volume_attribute_float3(kg, sd, v_desc); - object_dir_transform(kg, sd, &velocity); - - /* Find advected P. */ - sd->P = P - (time - time_offset) * velocity_scale * velocity; - - /* Find advected velocity. */ - velocity = primitive_volume_attribute_float3(kg, sd, v_desc); - object_dir_transform(kg, sd, &velocity); - - /* Find advected P. */ - sd->P = P - (time - time_offset) * velocity_scale * velocity; - } -# endif - } - - /* evaluate shader */ -# ifdef __SVM__ -# ifdef __OSL__ - if (kg->osl) { - OSLShader::eval_volume(kg, state, sd, path_flag); - } - else -# endif - { - svm_eval_nodes<KERNEL_FEATURE_NODE_MASK_VOLUME, SHADER_TYPE_VOLUME>( - kg, state, sd, NULL, path_flag); - } -# endif - - /* Merge closures to avoid exceeding number of closures limit. */ - if (!shadow) { - if (i > 0) { - shader_merge_volume_closures(sd); - } - } - } -} - -#endif /* __VOLUME__ */ - -/* Displacement Evaluation */ - -template<typename ConstIntegratorGenericState> -ccl_device void shader_eval_displacement(KernelGlobals kg, - ConstIntegratorGenericState state, - ccl_private ShaderData *sd) -{ - sd->num_closure = 0; - sd->num_closure_left = 0; - - /* this will modify sd->P */ -#ifdef __SVM__ -# ifdef __OSL__ - if (kg->osl) - OSLShader::eval_displacement(kg, state, sd); - else -# endif - { - svm_eval_nodes<KERNEL_FEATURE_NODE_MASK_DISPLACEMENT, SHADER_TYPE_DISPLACEMENT>( - kg, state, sd, NULL, 0); - } -#endif -} - -/* Cryptomatte */ - -ccl_device float shader_cryptomatte_id(KernelGlobals kg, int shader) -{ - return kernel_data_fetch(shaders, (shader & SHADER_MASK)).cryptomatte_id; -} - -CCL_NAMESPACE_END diff --git a/intern/cycles/kernel/integrator/subsurface.h b/intern/cycles/kernel/integrator/subsurface.h index d26890a113c..15c2cb1c708 100644 --- a/intern/cycles/kernel/integrator/subsurface.h +++ b/intern/cycles/kernel/integrator/subsurface.h @@ -15,9 +15,9 @@ #include "kernel/integrator/intersect_volume_stack.h" #include "kernel/integrator/path_state.h" -#include "kernel/integrator/shader_eval.h" #include "kernel/integrator/subsurface_disk.h" #include "kernel/integrator/subsurface_random_walk.h" +#include "kernel/integrator/surface_shader.h" CCL_NAMESPACE_BEGIN @@ -51,7 +51,7 @@ ccl_device int subsurface_bounce(KernelGlobals kg, PATH_RAY_SUBSURFACE_RANDOM_WALK); /* Compute weight, optionally including Fresnel from entry point. */ - Spectrum weight = shader_bssrdf_sample_weight(sd, sc); + Spectrum weight = surface_shader_bssrdf_sample_weight(sd, sc); if (bssrdf->roughness != FLT_MAX) { path_flag |= PATH_RAY_SUBSURFACE_USE_FRESNEL; } @@ -89,7 +89,7 @@ ccl_device void subsurface_shader_data_setup(KernelGlobals kg, /* Get bump mapped normal from shader evaluation at exit point. */ float3 N = sd->N; if (sd->flag & SD_HAS_BSSRDF_BUMP) { - N = shader_bssrdf_normal(sd); + N = surface_shader_bssrdf_normal(sd); } /* Setup diffuse BSDF at the exit point. This replaces shader_eval_surface. */ diff --git a/intern/cycles/kernel/integrator/surface_shader.h b/intern/cycles/kernel/integrator/surface_shader.h new file mode 100644 index 00000000000..f40ff3c33ee --- /dev/null +++ b/intern/cycles/kernel/integrator/surface_shader.h @@ -0,0 +1,587 @@ +/* SPDX-License-Identifier: Apache-2.0 + * Copyright 2011-2022 Blender Foundation */ + +/* Functions to evaluate shaders. */ + +#pragma once + +#include "kernel/closure/alloc.h" +#include "kernel/closure/bsdf.h" +#include "kernel/closure/bsdf_util.h" +#include "kernel/closure/emissive.h" + +#include "kernel/svm/svm.h" + +#ifdef __OSL__ +# include "kernel/osl/shader.h" +#endif + +CCL_NAMESPACE_BEGIN + +ccl_device_inline void surface_shader_prepare_closures(KernelGlobals kg, + ConstIntegratorState state, + ccl_private ShaderData *sd, + const uint32_t path_flag) +{ + /* Filter out closures. */ + if (kernel_data.integrator.filter_closures) { + if (kernel_data.integrator.filter_closures & FILTER_CLOSURE_EMISSION) { + sd->closure_emission_background = zero_spectrum(); + } + + if (kernel_data.integrator.filter_closures & FILTER_CLOSURE_DIRECT_LIGHT) { + sd->flag &= ~SD_BSDF_HAS_EVAL; + } + + if (path_flag & PATH_RAY_CAMERA) { + for (int i = 0; i < sd->num_closure; i++) { + ccl_private ShaderClosure *sc = &sd->closure[i]; + + if ((CLOSURE_IS_BSDF_DIFFUSE(sc->type) && + (kernel_data.integrator.filter_closures & FILTER_CLOSURE_DIFFUSE)) || + (CLOSURE_IS_BSDF_GLOSSY(sc->type) && + (kernel_data.integrator.filter_closures & FILTER_CLOSURE_GLOSSY)) || + (CLOSURE_IS_BSDF_TRANSMISSION(sc->type) && + (kernel_data.integrator.filter_closures & FILTER_CLOSURE_TRANSMISSION))) { + sc->type = CLOSURE_NONE_ID; + sc->sample_weight = 0.0f; + } + else if ((CLOSURE_IS_BSDF_TRANSPARENT(sc->type) && + (kernel_data.integrator.filter_closures & FILTER_CLOSURE_TRANSPARENT))) { + sc->type = CLOSURE_HOLDOUT_ID; + sc->sample_weight = 0.0f; + sd->flag |= SD_HOLDOUT; + } + } + } + } + + /* Defensive sampling. + * + * We can likely also do defensive sampling at deeper bounces, particularly + * for cases like a perfect mirror but possibly also others. This will need + * a good heuristic. */ + if (INTEGRATOR_STATE(state, path, bounce) + INTEGRATOR_STATE(state, path, transparent_bounce) == + 0 && + sd->num_closure > 1) { + float sum = 0.0f; + + for (int i = 0; i < sd->num_closure; i++) { + ccl_private ShaderClosure *sc = &sd->closure[i]; + if (CLOSURE_IS_BSDF_OR_BSSRDF(sc->type)) { + sum += sc->sample_weight; + } + } + + for (int i = 0; i < sd->num_closure; i++) { + ccl_private ShaderClosure *sc = &sd->closure[i]; + if (CLOSURE_IS_BSDF_OR_BSSRDF(sc->type)) { + sc->sample_weight = max(sc->sample_weight, 0.125f * sum); + } + } + } + + /* Filter glossy. + * + * Blurring of bsdf after bounces, for rays that have a small likelihood + * of following this particular path (diffuse, rough glossy) */ + if (kernel_data.integrator.filter_glossy != FLT_MAX +#ifdef __MNEE__ + && !(INTEGRATOR_STATE(state, path, mnee) & PATH_MNEE_VALID) +#endif + ) { + float blur_pdf = kernel_data.integrator.filter_glossy * + INTEGRATOR_STATE(state, path, min_ray_pdf); + + if (blur_pdf < 1.0f) { + float blur_roughness = sqrtf(1.0f - blur_pdf) * 0.5f; + + for (int i = 0; i < sd->num_closure; i++) { + ccl_private ShaderClosure *sc = &sd->closure[i]; + if (CLOSURE_IS_BSDF(sc->type)) { + bsdf_blur(kg, sc, blur_roughness); + } + } + } + } +} + +/* BSDF */ + +ccl_device_inline bool surface_shader_is_transmission(ccl_private const ShaderData *sd, + const float3 omega_in) +{ + return dot(sd->N, omega_in) < 0.0f; +} + +ccl_device_forceinline bool _surface_shader_exclude(ClosureType type, uint light_shader_flags) +{ + if (!(light_shader_flags & SHADER_EXCLUDE_ANY)) { + return false; + } + if (light_shader_flags & SHADER_EXCLUDE_DIFFUSE) { + if (CLOSURE_IS_BSDF_DIFFUSE(type)) { + return true; + } + } + if (light_shader_flags & SHADER_EXCLUDE_GLOSSY) { + if (CLOSURE_IS_BSDF_GLOSSY(type)) { + return true; + } + } + if (light_shader_flags & SHADER_EXCLUDE_TRANSMIT) { + if (CLOSURE_IS_BSDF_TRANSMISSION(type)) { + return true; + } + } + return false; +} + +ccl_device_inline float _surface_shader_bsdf_eval_mis(KernelGlobals kg, + ccl_private ShaderData *sd, + const float3 omega_in, + const bool is_transmission, + ccl_private const ShaderClosure *skip_sc, + ccl_private BsdfEval *result_eval, + float sum_pdf, + float sum_sample_weight, + const uint light_shader_flags) +{ + /* This is the veach one-sample model with balance heuristic, + * some PDF factors drop out when using balance heuristic weighting. */ + for (int i = 0; i < sd->num_closure; i++) { + ccl_private const ShaderClosure *sc = &sd->closure[i]; + + if (sc == skip_sc) { + continue; + } + + if (CLOSURE_IS_BSDF_OR_BSSRDF(sc->type)) { + if (CLOSURE_IS_BSDF(sc->type) && !_surface_shader_exclude(sc->type, light_shader_flags)) { + float bsdf_pdf = 0.0f; + Spectrum eval = bsdf_eval(kg, sd, sc, omega_in, is_transmission, &bsdf_pdf); + + if (bsdf_pdf != 0.0f) { + bsdf_eval_accum(result_eval, sc->type, eval * sc->weight); + sum_pdf += bsdf_pdf * sc->sample_weight; + } + } + + sum_sample_weight += sc->sample_weight; + } + } + + return (sum_sample_weight > 0.0f) ? sum_pdf / sum_sample_weight : 0.0f; +} + +#ifndef __KERNEL_CUDA__ +ccl_device +#else +ccl_device_inline +#endif + float + surface_shader_bsdf_eval(KernelGlobals kg, + ccl_private ShaderData *sd, + const float3 omega_in, + const bool is_transmission, + ccl_private BsdfEval *bsdf_eval, + const uint light_shader_flags) +{ + bsdf_eval_init(bsdf_eval, CLOSURE_NONE_ID, zero_spectrum()); + + return _surface_shader_bsdf_eval_mis( + kg, sd, omega_in, is_transmission, NULL, bsdf_eval, 0.0f, 0.0f, light_shader_flags); +} + +/* Randomly sample a BSSRDF or BSDF proportional to ShaderClosure.sample_weight. */ +ccl_device_inline ccl_private const ShaderClosure *surface_shader_bsdf_bssrdf_pick( + ccl_private const ShaderData *ccl_restrict sd, ccl_private float2 *rand_bsdf) +{ + int sampled = 0; + + if (sd->num_closure > 1) { + /* Pick a BSDF or based on sample weights. */ + float sum = 0.0f; + + for (int i = 0; i < sd->num_closure; i++) { + ccl_private const ShaderClosure *sc = &sd->closure[i]; + + if (CLOSURE_IS_BSDF_OR_BSSRDF(sc->type)) { + sum += sc->sample_weight; + } + } + + float r = (*rand_bsdf).x * sum; + float partial_sum = 0.0f; + + for (int i = 0; i < sd->num_closure; i++) { + ccl_private const ShaderClosure *sc = &sd->closure[i]; + + if (CLOSURE_IS_BSDF_OR_BSSRDF(sc->type)) { + float next_sum = partial_sum + sc->sample_weight; + + if (r < next_sum) { + sampled = i; + + /* Rescale to reuse for direction sample, to better preserve stratification. */ + (*rand_bsdf).x = (r - partial_sum) / sc->sample_weight; + break; + } + + partial_sum = next_sum; + } + } + } + + return &sd->closure[sampled]; +} + +/* Return weight for picked BSSRDF. */ +ccl_device_inline Spectrum +surface_shader_bssrdf_sample_weight(ccl_private const ShaderData *ccl_restrict sd, + ccl_private const ShaderClosure *ccl_restrict bssrdf_sc) +{ + Spectrum weight = bssrdf_sc->weight; + + if (sd->num_closure > 1) { + float sum = 0.0f; + for (int i = 0; i < sd->num_closure; i++) { + ccl_private const ShaderClosure *sc = &sd->closure[i]; + + if (CLOSURE_IS_BSDF_OR_BSSRDF(sc->type)) { + sum += sc->sample_weight; + } + } + weight *= sum / bssrdf_sc->sample_weight; + } + + return weight; +} + +/* Sample direction for picked BSDF, and return evaluation and pdf for all + * BSDFs combined using MIS. */ +ccl_device int surface_shader_bsdf_sample_closure(KernelGlobals kg, + ccl_private ShaderData *sd, + ccl_private const ShaderClosure *sc, + const float2 rand_bsdf, + ccl_private BsdfEval *bsdf_eval, + ccl_private float3 *omega_in, + ccl_private float *pdf) +{ + /* BSSRDF should already have been handled elsewhere. */ + kernel_assert(CLOSURE_IS_BSDF(sc->type)); + + int label; + Spectrum eval = zero_spectrum(); + + *pdf = 0.0f; + label = bsdf_sample(kg, sd, sc, rand_bsdf.x, rand_bsdf.y, &eval, omega_in, pdf); + + if (*pdf != 0.0f) { + bsdf_eval_init(bsdf_eval, sc->type, eval * sc->weight); + + if (sd->num_closure > 1) { + const bool is_transmission = surface_shader_is_transmission(sd, *omega_in); + float sweight = sc->sample_weight; + *pdf = _surface_shader_bsdf_eval_mis( + kg, sd, *omega_in, is_transmission, sc, bsdf_eval, *pdf * sweight, sweight, 0); + } + } + + return label; +} + +ccl_device float surface_shader_average_roughness(ccl_private const ShaderData *sd) +{ + float roughness = 0.0f; + float sum_weight = 0.0f; + + for (int i = 0; i < sd->num_closure; i++) { + ccl_private const ShaderClosure *sc = &sd->closure[i]; + + if (CLOSURE_IS_BSDF(sc->type)) { + /* sqrt once to undo the squaring from multiplying roughness on the + * two axes, and once for the squared roughness convention. */ + float weight = fabsf(average(sc->weight)); + roughness += weight * sqrtf(safe_sqrtf(bsdf_get_roughness_squared(sc))); + sum_weight += weight; + } + } + + return (sum_weight > 0.0f) ? roughness / sum_weight : 0.0f; +} + +ccl_device Spectrum surface_shader_transparency(KernelGlobals kg, ccl_private const ShaderData *sd) +{ + if (sd->flag & SD_HAS_ONLY_VOLUME) { + return one_spectrum(); + } + else if (sd->flag & SD_TRANSPARENT) { + return sd->closure_transparent_extinction; + } + else { + return zero_spectrum(); + } +} + +ccl_device void surface_shader_disable_transparency(KernelGlobals kg, ccl_private ShaderData *sd) +{ + if (sd->flag & SD_TRANSPARENT) { + for (int i = 0; i < sd->num_closure; i++) { + ccl_private ShaderClosure *sc = &sd->closure[i]; + + if (sc->type == CLOSURE_BSDF_TRANSPARENT_ID) { + sc->sample_weight = 0.0f; + sc->weight = zero_spectrum(); + } + } + + sd->flag &= ~SD_TRANSPARENT; + } +} + +ccl_device Spectrum surface_shader_alpha(KernelGlobals kg, ccl_private const ShaderData *sd) +{ + Spectrum alpha = one_spectrum() - surface_shader_transparency(kg, sd); + + alpha = saturate(alpha); + + return alpha; +} + +ccl_device Spectrum surface_shader_diffuse(KernelGlobals kg, ccl_private const ShaderData *sd) +{ + Spectrum eval = zero_spectrum(); + + for (int i = 0; i < sd->num_closure; i++) { + ccl_private const ShaderClosure *sc = &sd->closure[i]; + + if (CLOSURE_IS_BSDF_DIFFUSE(sc->type) || CLOSURE_IS_BSSRDF(sc->type)) + eval += sc->weight; + } + + return eval; +} + +ccl_device Spectrum surface_shader_glossy(KernelGlobals kg, ccl_private const ShaderData *sd) +{ + Spectrum eval = zero_spectrum(); + + for (int i = 0; i < sd->num_closure; i++) { + ccl_private const ShaderClosure *sc = &sd->closure[i]; + + if (CLOSURE_IS_BSDF_GLOSSY(sc->type)) + eval += sc->weight; + } + + return eval; +} + +ccl_device Spectrum surface_shader_transmission(KernelGlobals kg, ccl_private const ShaderData *sd) +{ + Spectrum eval = zero_spectrum(); + + for (int i = 0; i < sd->num_closure; i++) { + ccl_private const ShaderClosure *sc = &sd->closure[i]; + + if (CLOSURE_IS_BSDF_TRANSMISSION(sc->type)) + eval += sc->weight; + } + + return eval; +} + +ccl_device float3 surface_shader_average_normal(KernelGlobals kg, ccl_private const ShaderData *sd) +{ + float3 N = zero_float3(); + + for (int i = 0; i < sd->num_closure; i++) { + ccl_private const ShaderClosure *sc = &sd->closure[i]; + if (CLOSURE_IS_BSDF_OR_BSSRDF(sc->type)) + N += sc->N * fabsf(average(sc->weight)); + } + + return (is_zero(N)) ? sd->N : normalize(N); +} + +ccl_device Spectrum surface_shader_ao(KernelGlobals kg, + ccl_private const ShaderData *sd, + const float ao_factor, + ccl_private float3 *N_) +{ + Spectrum eval = zero_spectrum(); + float3 N = zero_float3(); + + for (int i = 0; i < sd->num_closure; i++) { + ccl_private const ShaderClosure *sc = &sd->closure[i]; + + if (CLOSURE_IS_BSDF_DIFFUSE(sc->type)) { + ccl_private const DiffuseBsdf *bsdf = (ccl_private const DiffuseBsdf *)sc; + eval += sc->weight * ao_factor; + N += bsdf->N * fabsf(average(sc->weight)); + } + } + + *N_ = (is_zero(N)) ? sd->N : normalize(N); + return eval; +} + +#ifdef __SUBSURFACE__ +ccl_device float3 surface_shader_bssrdf_normal(ccl_private const ShaderData *sd) +{ + float3 N = zero_float3(); + + for (int i = 0; i < sd->num_closure; i++) { + ccl_private const ShaderClosure *sc = &sd->closure[i]; + + if (CLOSURE_IS_BSSRDF(sc->type)) { + ccl_private const Bssrdf *bssrdf = (ccl_private const Bssrdf *)sc; + float avg_weight = fabsf(average(sc->weight)); + + N += bssrdf->N * avg_weight; + } + } + + return (is_zero(N)) ? sd->N : normalize(N); +} +#endif /* __SUBSURFACE__ */ + +/* Constant emission optimization */ + +ccl_device bool surface_shader_constant_emission(KernelGlobals kg, + int shader, + ccl_private Spectrum *eval) +{ + int shader_index = shader & SHADER_MASK; + int shader_flag = kernel_data_fetch(shaders, shader_index).flags; + + if (shader_flag & SD_HAS_CONSTANT_EMISSION) { + const float3 emission_rgb = make_float3( + kernel_data_fetch(shaders, shader_index).constant_emission[0], + kernel_data_fetch(shaders, shader_index).constant_emission[1], + kernel_data_fetch(shaders, shader_index).constant_emission[2]); + *eval = rgb_to_spectrum(emission_rgb); + + return true; + } + + return false; +} + +/* Background */ + +ccl_device Spectrum surface_shader_background(ccl_private const ShaderData *sd) +{ + if (sd->flag & SD_EMISSION) { + return sd->closure_emission_background; + } + else { + return zero_spectrum(); + } +} + +/* Emission */ + +ccl_device Spectrum surface_shader_emission(ccl_private const ShaderData *sd) +{ + if (sd->flag & SD_EMISSION) { + return emissive_simple_eval(sd->Ng, sd->I) * sd->closure_emission_background; + } + else { + return zero_spectrum(); + } +} + +/* Holdout */ + +ccl_device Spectrum surface_shader_apply_holdout(KernelGlobals kg, ccl_private ShaderData *sd) +{ + Spectrum weight = zero_spectrum(); + + /* For objects marked as holdout, preserve transparency and remove all other + * closures, replacing them with a holdout weight. */ + if (sd->object_flag & SD_OBJECT_HOLDOUT_MASK) { + if ((sd->flag & SD_TRANSPARENT) && !(sd->flag & SD_HAS_ONLY_VOLUME)) { + weight = one_spectrum() - sd->closure_transparent_extinction; + + for (int i = 0; i < sd->num_closure; i++) { + ccl_private ShaderClosure *sc = &sd->closure[i]; + if (!CLOSURE_IS_BSDF_TRANSPARENT(sc->type)) { + sc->type = NBUILTIN_CLOSURES; + } + } + + sd->flag &= ~(SD_CLOSURE_FLAGS - (SD_TRANSPARENT | SD_BSDF)); + } + else { + weight = one_spectrum(); + } + } + else { + for (int i = 0; i < sd->num_closure; i++) { + ccl_private const ShaderClosure *sc = &sd->closure[i]; + if (CLOSURE_IS_HOLDOUT(sc->type)) { + weight += sc->weight; + } + } + } + + return weight; +} + +/* Surface Evaluation */ + +template<uint node_feature_mask, typename ConstIntegratorGenericState> +ccl_device void surface_shader_eval(KernelGlobals kg, + ConstIntegratorGenericState state, + ccl_private ShaderData *ccl_restrict sd, + ccl_global float *ccl_restrict buffer, + uint32_t path_flag, + bool use_caustics_storage = false) +{ + /* If path is being terminated, we are tracing a shadow ray or evaluating + * emission, then we don't need to store closures. The emission and shadow + * shader data also do not have a closure array to save GPU memory. */ + int max_closures; + if (path_flag & (PATH_RAY_TERMINATE | PATH_RAY_SHADOW | PATH_RAY_EMISSION)) { + max_closures = 0; + } + else { + max_closures = use_caustics_storage ? CAUSTICS_MAX_CLOSURE : kernel_data.max_closures; + } + + sd->num_closure = 0; + sd->num_closure_left = max_closures; + +#ifdef __OSL__ + if (kg->osl) { + if (sd->object == OBJECT_NONE && sd->lamp == LAMP_NONE) { + OSLShader::eval_background(kg, state, sd, path_flag); + } + else { + OSLShader::eval_surface(kg, state, sd, path_flag); + } + } + else +#endif + { +#ifdef __SVM__ + svm_eval_nodes<node_feature_mask, SHADER_TYPE_SURFACE>(kg, state, sd, buffer, path_flag); +#else + if (sd->object == OBJECT_NONE) { + sd->closure_emission_background = make_spectrum(0.8f); + sd->flag |= SD_EMISSION; + } + else { + ccl_private DiffuseBsdf *bsdf = (ccl_private DiffuseBsdf *)bsdf_alloc( + sd, sizeof(DiffuseBsdf), make_spectrum(0.8f)); + if (bsdf != NULL) { + bsdf->N = sd->N; + sd->flag |= bsdf_diffuse_setup(bsdf); + } + } +#endif + } +} + +CCL_NAMESPACE_END diff --git a/intern/cycles/kernel/integrator/volume_shader.h b/intern/cycles/kernel/integrator/volume_shader.h new file mode 100644 index 00000000000..a1d191e2d32 --- /dev/null +++ b/intern/cycles/kernel/integrator/volume_shader.h @@ -0,0 +1,353 @@ +/* SPDX-License-Identifier: Apache-2.0 + * Copyright 2011-2022 Blender Foundation */ + +/* Volume shader evaluation and sampling. */ + +#pragma once + +#include "kernel/closure/alloc.h" +#include "kernel/closure/bsdf.h" +#include "kernel/closure/bsdf_util.h" +#include "kernel/closure/emissive.h" + +#include "kernel/svm/svm.h" + +#ifdef __OSL__ +# include "kernel/osl/shader.h" +#endif + +CCL_NAMESPACE_BEGIN + +#ifdef __VOLUME__ + +/* Merging */ +ccl_device_inline void volume_shader_merge_closures(ccl_private ShaderData *sd) +{ + /* Merge identical closures to save closure space with stacked volumes. */ + for (int i = 0; i < sd->num_closure; i++) { + ccl_private ShaderClosure *sci = &sd->closure[i]; + + if (sci->type != CLOSURE_VOLUME_HENYEY_GREENSTEIN_ID) { + continue; + } + + for (int j = i + 1; j < sd->num_closure; j++) { + ccl_private ShaderClosure *scj = &sd->closure[j]; + if (sci->type != scj->type) { + continue; + } + + ccl_private const HenyeyGreensteinVolume *hgi = (ccl_private const HenyeyGreensteinVolume *) + sci; + ccl_private const HenyeyGreensteinVolume *hgj = (ccl_private const HenyeyGreensteinVolume *) + scj; + if (!(hgi->g == hgj->g)) { + continue; + } + + sci->weight += scj->weight; + sci->sample_weight += scj->sample_weight; + + int size = sd->num_closure - (j + 1); + if (size > 0) { + for (int k = 0; k < size; k++) { + scj[k] = scj[k + 1]; + } + } + + sd->num_closure--; + kernel_assert(sd->num_closure >= 0); + j--; + } + } +} + +ccl_device_inline void volume_shader_copy_phases(ccl_private ShaderVolumePhases *ccl_restrict + phases, + ccl_private const ShaderData *ccl_restrict sd) +{ + phases->num_closure = 0; + + for (int i = 0; i < sd->num_closure; i++) { + ccl_private const ShaderClosure *from_sc = &sd->closure[i]; + ccl_private const HenyeyGreensteinVolume *from_hg = + (ccl_private const HenyeyGreensteinVolume *)from_sc; + + if (from_sc->type == CLOSURE_VOLUME_HENYEY_GREENSTEIN_ID) { + ccl_private ShaderVolumeClosure *to_sc = &phases->closure[phases->num_closure]; + + to_sc->weight = from_sc->weight; + to_sc->sample_weight = from_sc->sample_weight; + to_sc->g = from_hg->g; + phases->num_closure++; + if (phases->num_closure >= MAX_VOLUME_CLOSURE) { + break; + } + } + } +} + +ccl_device_inline float _volume_shader_phase_eval_mis(ccl_private const ShaderData *sd, + ccl_private const ShaderVolumePhases *phases, + const float3 omega_in, + int skip_phase, + ccl_private BsdfEval *result_eval, + float sum_pdf, + float sum_sample_weight) +{ + for (int i = 0; i < phases->num_closure; i++) { + if (i == skip_phase) + continue; + + ccl_private const ShaderVolumeClosure *svc = &phases->closure[i]; + float phase_pdf = 0.0f; + Spectrum eval = volume_phase_eval(sd, svc, omega_in, &phase_pdf); + + if (phase_pdf != 0.0f) { + bsdf_eval_accum(result_eval, CLOSURE_VOLUME_HENYEY_GREENSTEIN_ID, eval); + sum_pdf += phase_pdf * svc->sample_weight; + } + + sum_sample_weight += svc->sample_weight; + } + + return (sum_sample_weight > 0.0f) ? sum_pdf / sum_sample_weight : 0.0f; +} + +ccl_device float volume_shader_phase_eval(KernelGlobals kg, + ccl_private const ShaderData *sd, + ccl_private const ShaderVolumePhases *phases, + const float3 omega_in, + ccl_private BsdfEval *phase_eval) +{ + bsdf_eval_init(phase_eval, CLOSURE_VOLUME_HENYEY_GREENSTEIN_ID, zero_spectrum()); + + return _volume_shader_phase_eval_mis(sd, phases, omega_in, -1, phase_eval, 0.0f, 0.0f); +} + +ccl_device int volume_shader_phase_sample(KernelGlobals kg, + ccl_private const ShaderData *sd, + ccl_private const ShaderVolumePhases *phases, + float2 rand_phase, + ccl_private BsdfEval *phase_eval, + ccl_private float3 *omega_in, + ccl_private float *pdf) +{ + int sampled = 0; + + if (phases->num_closure > 1) { + /* pick a phase closure based on sample weights */ + float sum = 0.0f; + + for (sampled = 0; sampled < phases->num_closure; sampled++) { + ccl_private const ShaderVolumeClosure *svc = &phases->closure[sampled]; + sum += svc->sample_weight; + } + + float r = rand_phase.x * sum; + float partial_sum = 0.0f; + + for (sampled = 0; sampled < phases->num_closure; sampled++) { + ccl_private const ShaderVolumeClosure *svc = &phases->closure[sampled]; + float next_sum = partial_sum + svc->sample_weight; + + if (r <= next_sum) { + /* Rescale to reuse for BSDF direction sample. */ + rand_phase.x = (r - partial_sum) / svc->sample_weight; + break; + } + + partial_sum = next_sum; + } + + if (sampled == phases->num_closure) { + *pdf = 0.0f; + return LABEL_NONE; + } + } + + /* todo: this isn't quite correct, we don't weight anisotropy properly + * depending on color channels, even if this is perhaps not a common case */ + ccl_private const ShaderVolumeClosure *svc = &phases->closure[sampled]; + int label; + Spectrum eval = zero_spectrum(); + + *pdf = 0.0f; + label = volume_phase_sample(sd, svc, rand_phase.x, rand_phase.y, &eval, omega_in, pdf); + + if (*pdf != 0.0f) { + bsdf_eval_init(phase_eval, CLOSURE_VOLUME_HENYEY_GREENSTEIN_ID, eval); + } + + return label; +} + +ccl_device int volume_shader_phase_sample_closure(KernelGlobals kg, + ccl_private const ShaderData *sd, + ccl_private const ShaderVolumeClosure *sc, + const float2 rand_phase, + ccl_private BsdfEval *phase_eval, + ccl_private float3 *omega_in, + ccl_private float *pdf) +{ + int label; + Spectrum eval = zero_spectrum(); + + *pdf = 0.0f; + label = volume_phase_sample(sd, sc, rand_phase.x, rand_phase.y, &eval, omega_in, pdf); + + if (*pdf != 0.0f) + bsdf_eval_init(phase_eval, CLOSURE_VOLUME_HENYEY_GREENSTEIN_ID, eval); + + return label; +} + +/* Motion Blur */ + +# ifdef __OBJECT_MOTION__ +ccl_device_inline void volume_shader_motion_blur(KernelGlobals kg, + ccl_private ShaderData *ccl_restrict sd) +{ + if ((sd->object_flag & SD_OBJECT_HAS_VOLUME_MOTION) == 0) { + return; + } + + AttributeDescriptor v_desc = find_attribute(kg, sd, ATTR_STD_VOLUME_VELOCITY); + kernel_assert(v_desc.offset != ATTR_STD_NOT_FOUND); + + const float3 P = sd->P; + const float velocity_scale = kernel_data_fetch(objects, sd->object).velocity_scale; + const float time_offset = kernel_data.cam.motion_position == MOTION_POSITION_CENTER ? 0.5f : + 0.0f; + const float time = kernel_data.cam.motion_position == MOTION_POSITION_END ? + (1.0f - kernel_data.cam.shuttertime) + sd->time : + sd->time; + + /* Use a 1st order semi-lagrangian advection scheme to estimate what volume quantity + * existed, or will exist, at the given time: + * + * `phi(x, T) = phi(x - (T - t) * u(x, T), t)` + * + * where + * + * x : position + * T : super-sampled time (or ray time) + * t : current time of the simulation (in rendering we assume this is center frame with + * relative time = 0) + * phi : the volume quantity + * u : the velocity field + * + * But first we need to determine the velocity field `u(x, T)`, which we can estimate also + * using semi-lagrangian advection. + * + * `u(x, T) = u(x - (T - t) * u(x, T), t)` + * + * This is the typical way to model self-advection in fluid dynamics, however, we do not + * account for other forces affecting the velocity during simulation (pressure, buoyancy, + * etc.): this gives a linear interpolation when fluid are mostly "curvy". For better + * results, a higher order interpolation scheme can be used (at the cost of more lookups), + * or an interpolation of the velocity fields for the previous and next frames could also + * be used to estimate `u(x, T)` (which will cost more memory and lookups). + * + * References: + * "Eulerian Motion Blur", Kim and Ko, 2007 + * "Production Volume Rendering", Wreninge et al., 2012 + */ + + /* Find velocity. */ + float3 velocity = primitive_volume_attribute_float3(kg, sd, v_desc); + object_dir_transform(kg, sd, &velocity); + + /* Find advected P. */ + sd->P = P - (time - time_offset) * velocity_scale * velocity; + + /* Find advected velocity. */ + velocity = primitive_volume_attribute_float3(kg, sd, v_desc); + object_dir_transform(kg, sd, &velocity); + + /* Find advected P. */ + sd->P = P - (time - time_offset) * velocity_scale * velocity; +} +# endif + +/* Volume Evaluation */ + +template<const bool shadow, typename StackReadOp, typename ConstIntegratorGenericState> +ccl_device_inline void volume_shader_eval(KernelGlobals kg, + ConstIntegratorGenericState state, + ccl_private ShaderData *ccl_restrict sd, + const uint32_t path_flag, + StackReadOp stack_read) +{ + /* If path is being terminated, we are tracing a shadow ray or evaluating + * emission, then we don't need to store closures. The emission and shadow + * shader data also do not have a closure array to save GPU memory. */ + int max_closures; + if (path_flag & (PATH_RAY_TERMINATE | PATH_RAY_SHADOW | PATH_RAY_EMISSION)) { + max_closures = 0; + } + else { + max_closures = kernel_data.max_closures; + } + + /* reset closures once at the start, we will be accumulating the closures + * for all volumes in the stack into a single array of closures */ + sd->num_closure = 0; + sd->num_closure_left = max_closures; + sd->flag = 0; + sd->object_flag = 0; + + for (int i = 0;; i++) { + const VolumeStack entry = stack_read(i); + if (entry.shader == SHADER_NONE) { + break; + } + + /* Setup shader-data from stack. it's mostly setup already in + * shader_setup_from_volume, this switching should be quick. */ + sd->object = entry.object; + sd->lamp = LAMP_NONE; + sd->shader = entry.shader; + + sd->flag &= ~SD_SHADER_FLAGS; + sd->flag |= kernel_data_fetch(shaders, (sd->shader & SHADER_MASK)).flags; + sd->object_flag &= ~SD_OBJECT_FLAGS; + + if (sd->object != OBJECT_NONE) { + sd->object_flag |= kernel_data_fetch(object_flag, sd->object); + +# ifdef __OBJECT_MOTION__ + /* todo: this is inefficient for motion blur, we should be + * caching matrices instead of recomputing them each step */ + shader_setup_object_transforms(kg, sd, sd->time); + + volume_shader_motion_blur(kg, sd); +# endif + } + + /* evaluate shader */ +# ifdef __SVM__ +# ifdef __OSL__ + if (kg->osl) { + OSLShader::eval_volume(kg, state, sd, path_flag); + } + else +# endif + { + svm_eval_nodes<KERNEL_FEATURE_NODE_MASK_VOLUME, SHADER_TYPE_VOLUME>( + kg, state, sd, NULL, path_flag); + } +# endif + + /* Merge closures to avoid exceeding number of closures limit. */ + if (!shadow) { + if (i > 0) { + volume_shader_merge_closures(sd); + } + } + } +} + +#endif /* __VOLUME__ */ + +CCL_NAMESPACE_END |