Welcome to mirror list, hosted at ThFree Co, Russian Federation.

git.blender.org/blender.git - Unnamed repository; edit this file 'description' to name the repository.
summaryrefslogtreecommitdiff
path: root/intern/cycles/kernel/kernel_path_surface.h
diff options
context:
space:
mode:
Diffstat (limited to 'intern/cycles/kernel/kernel_path_surface.h')
-rw-r--r--intern/cycles/kernel/kernel_path_surface.h295
1 files changed, 295 insertions, 0 deletions
diff --git a/intern/cycles/kernel/kernel_path_surface.h b/intern/cycles/kernel/kernel_path_surface.h
new file mode 100644
index 00000000000..85bdebf195e
--- /dev/null
+++ b/intern/cycles/kernel/kernel_path_surface.h
@@ -0,0 +1,295 @@
+/*
+ * 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
+ */
+
+CCL_NAMESPACE_BEGIN
+
+#if defined(__BRANCHED_PATH__) || defined(__SUBSURFACE__)
+
+/* branched path tracing: connect path directly to position on one or more lights and add it to L */
+ccl_device void kernel_branched_path_surface_connect_light(KernelGlobals *kg, RNG *rng,
+ ShaderData *sd, PathState *state, float3 throughput, float num_samples_adjust, PathRadiance *L, bool sample_all_lights)
+{
+ /* sample illumination from lights to find path contribution */
+ if(sd->flag & SD_BSDF_HAS_EVAL) {
+ Ray light_ray;
+ BsdfEval L_light;
+ bool is_lamp;
+
+#ifdef __OBJECT_MOTION__
+ light_ray.time = sd->time;
+#endif
+
+ if(sample_all_lights) {
+ /* lamp sampling */
+ for(int i = 0; i < kernel_data.integrator.num_all_lights; i++) {
+ int num_samples = ceil_to_int(num_samples_adjust*light_select_num_samples(kg, i));
+ float num_samples_inv = num_samples_adjust/(num_samples*kernel_data.integrator.num_all_lights);
+ RNG lamp_rng = cmj_hash(*rng, i);
+
+ if(kernel_data.integrator.pdf_triangles != 0.0f)
+ num_samples_inv *= 0.5f;
+
+ for(int j = 0; j < num_samples; j++) {
+ float light_u, light_v;
+ path_branched_rng_2D(kg, &lamp_rng, state, j, num_samples, PRNG_LIGHT_U, &light_u, &light_v);
+
+ LightSample ls;
+ light_select(kg, i, light_u, light_v, sd->P, &ls);
+
+ if(direct_emission(kg, sd, &ls, &light_ray, &L_light, &is_lamp, state->bounce, state->transparent_bounce)) {
+ /* trace shadow ray */
+ float3 shadow;
+
+ if(!shadow_blocked(kg, state, &light_ray, &shadow)) {
+ /* accumulate */
+ path_radiance_accum_light(L, throughput*num_samples_inv, &L_light, shadow, num_samples_inv, state->bounce, is_lamp);
+ }
+ }
+ }
+ }
+
+ /* mesh light sampling */
+ if(kernel_data.integrator.pdf_triangles != 0.0f) {
+ int num_samples = ceil_to_int(num_samples_adjust*kernel_data.integrator.mesh_light_samples);
+ float num_samples_inv = num_samples_adjust/num_samples;
+
+ if(kernel_data.integrator.num_all_lights)
+ num_samples_inv *= 0.5f;
+
+ for(int j = 0; j < num_samples; j++) {
+ float light_t = path_branched_rng_1D(kg, rng, state, j, num_samples, PRNG_LIGHT);
+ float light_u, light_v;
+ path_branched_rng_2D(kg, rng, state, j, num_samples, PRNG_LIGHT_U, &light_u, &light_v);
+
+ /* only sample triangle lights */
+ if(kernel_data.integrator.num_all_lights)
+ light_t = 0.5f*light_t;
+
+ LightSample ls;
+ light_sample(kg, light_t, light_u, light_v, sd->time, sd->P, &ls);
+
+ if(direct_emission(kg, sd, &ls, &light_ray, &L_light, &is_lamp, state->bounce, state->transparent_bounce)) {
+ /* trace shadow ray */
+ float3 shadow;
+
+ if(!shadow_blocked(kg, state, &light_ray, &shadow)) {
+ /* accumulate */
+ path_radiance_accum_light(L, throughput*num_samples_inv, &L_light, shadow, num_samples_inv, state->bounce, is_lamp);
+ }
+ }
+ }
+ }
+ }
+ else {
+ float light_t = path_state_rng_1D(kg, rng, state, PRNG_LIGHT);
+ float light_u, light_v;
+ path_state_rng_2D(kg, rng, state, PRNG_LIGHT_U, &light_u, &light_v);
+
+ LightSample ls;
+ light_sample(kg, light_t, light_u, light_v, sd->time, sd->P, &ls);
+
+ /* sample random light */
+ if(direct_emission(kg, sd, &ls, &light_ray, &L_light, &is_lamp, state->bounce, state->transparent_bounce)) {
+ /* trace shadow ray */
+ float3 shadow;
+
+ if(!shadow_blocked(kg, state, &light_ray, &shadow)) {
+ /* accumulate */
+ path_radiance_accum_light(L, throughput, &L_light, shadow, num_samples_adjust, state->bounce, is_lamp);
+ }
+ }
+ }
+ }
+}
+
+/* branched path tracing: bounce off or through surface to with new direction stored in ray */
+ccl_device bool kernel_branched_path_surface_bounce(KernelGlobals *kg, RNG *rng,
+ ShaderData *sd, const ShaderClosure *sc, int sample, int num_samples,
+ float3 *throughput, PathState *state, PathRadiance *L, Ray *ray)
+{
+ /* sample BSDF */
+ float bsdf_pdf;
+ BsdfEval bsdf_eval;
+ float3 bsdf_omega_in;
+ differential3 bsdf_domega_in;
+ float bsdf_u, bsdf_v;
+ path_branched_rng_2D(kg, rng, state, sample, num_samples, PRNG_BSDF_U, &bsdf_u, &bsdf_v);
+ int label;
+
+ label = shader_bsdf_sample_closure(kg, sd, sc, bsdf_u, bsdf_v, &bsdf_eval,
+ &bsdf_omega_in, &bsdf_domega_in, &bsdf_pdf);
+
+ if(bsdf_pdf == 0.0f || bsdf_eval_is_zero(&bsdf_eval))
+ return false;
+
+ /* modify throughput */
+ path_radiance_bsdf_bounce(L, throughput, &bsdf_eval, bsdf_pdf, state->bounce, label);
+
+ /* modify path state */
+ path_state_next(kg, state, label);
+
+ /* setup ray */
+ ray->P = ray_offset(sd->P, (label & LABEL_TRANSMIT)? -sd->Ng: sd->Ng);
+ ray->D = bsdf_omega_in;
+ ray->t = FLT_MAX;
+#ifdef __RAY_DIFFERENTIALS__
+ ray->dP = sd->dP;
+ ray->dD = bsdf_domega_in;
+#endif
+#ifdef __OBJECT_MOTION__
+ ray->time = sd->time;
+#endif
+
+#ifdef __VOLUME__
+ /* enter/exit volume */
+ if(label & LABEL_TRANSMIT)
+ kernel_volume_stack_enter_exit(kg, sd, state->volume_stack);
+#endif
+
+ /* branch RNG state */
+ path_state_branch(state, sample, num_samples);
+
+ /* set MIS state */
+ state->min_ray_pdf = fminf(bsdf_pdf, FLT_MAX);
+ state->ray_pdf = bsdf_pdf;
+#ifdef __LAMP_MIS__
+ state->ray_t = 0.0f;
+#endif
+
+ return true;
+}
+
+#endif
+
+/* path tracing: connect path directly to position on a light and add it to L */
+ccl_device_inline void kernel_path_surface_connect_light(KernelGlobals *kg, RNG *rng,
+ ShaderData *sd, float3 throughput, PathState *state, PathRadiance *L)
+{
+#ifdef __EMISSION__
+ if(!(kernel_data.integrator.use_direct_light && (sd->flag & SD_BSDF_HAS_EVAL)))
+ return;
+
+ /* sample illumination from lights to find path contribution */
+ float light_t = path_state_rng_1D(kg, rng, state, PRNG_LIGHT);
+ float light_u, light_v;
+ path_state_rng_2D(kg, rng, state, PRNG_LIGHT_U, &light_u, &light_v);
+
+ Ray light_ray;
+ BsdfEval L_light;
+ bool is_lamp;
+
+#ifdef __OBJECT_MOTION__
+ light_ray.time = sd->time;
+#endif
+
+ LightSample ls;
+ light_sample(kg, light_t, light_u, light_v, sd->time, sd->P, &ls);
+
+ if(direct_emission(kg, sd, &ls, &light_ray, &L_light, &is_lamp, state->bounce, state->transparent_bounce)) {
+ /* trace shadow ray */
+ float3 shadow;
+
+ if(!shadow_blocked(kg, state, &light_ray, &shadow)) {
+ /* accumulate */
+ path_radiance_accum_light(L, throughput, &L_light, shadow, 1.0f, state->bounce, is_lamp);
+ }
+ }
+#endif
+}
+
+/* path tracing: bounce off or through surface to with new direction stored in ray */
+ccl_device_inline bool kernel_path_surface_bounce(KernelGlobals *kg, RNG *rng,
+ ShaderData *sd, float3 *throughput, PathState *state, PathRadiance *L, Ray *ray)
+{
+ /* no BSDF? we can stop here */
+ if(sd->flag & SD_BSDF) {
+ /* sample BSDF */
+ float bsdf_pdf;
+ BsdfEval bsdf_eval;
+ float3 bsdf_omega_in;
+ differential3 bsdf_domega_in;
+ float bsdf_u, bsdf_v;
+ path_state_rng_2D(kg, rng, state, PRNG_BSDF_U, &bsdf_u, &bsdf_v);
+ int label;
+
+ label = shader_bsdf_sample(kg, sd, bsdf_u, bsdf_v, &bsdf_eval,
+ &bsdf_omega_in, &bsdf_domega_in, &bsdf_pdf);
+
+ if(bsdf_pdf == 0.0f || bsdf_eval_is_zero(&bsdf_eval))
+ return false;
+
+ /* modify throughput */
+ path_radiance_bsdf_bounce(L, throughput, &bsdf_eval, bsdf_pdf, state->bounce, label);
+
+ /* set labels */
+ if(!(label & LABEL_TRANSPARENT)) {
+ state->ray_pdf = bsdf_pdf;
+#ifdef __LAMP_MIS__
+ state->ray_t = 0.0f;
+#endif
+ state->min_ray_pdf = fminf(bsdf_pdf, state->min_ray_pdf);
+ }
+
+ /* update path state */
+ path_state_next(kg, state, label);
+
+ /* setup ray */
+ ray->P = ray_offset(sd->P, (label & LABEL_TRANSMIT)? -sd->Ng: sd->Ng);
+ ray->D = bsdf_omega_in;
+
+ if(state->bounce == 0)
+ ray->t -= sd->ray_length; /* clipping works through transparent */
+ else
+ ray->t = FLT_MAX;
+
+#ifdef __RAY_DIFFERENTIALS__
+ ray->dP = sd->dP;
+ ray->dD = bsdf_domega_in;
+#endif
+
+#ifdef __VOLUME__
+ /* enter/exit volume */
+ if(label & LABEL_TRANSMIT)
+ kernel_volume_stack_enter_exit(kg, sd, state->volume_stack);
+#endif
+ return true;
+ }
+#ifdef __VOLUME__
+ else if(sd->flag & SD_HAS_ONLY_VOLUME) {
+ /* no surface shader but have a volume shader? act transparent */
+
+ /* update path state, count as transparent */
+ path_state_next(kg, state, LABEL_TRANSPARENT);
+
+ /* setup ray position, direction stays unchanged */
+ ray->P = ray_offset(sd->P, -sd->Ng);
+#ifdef __RAY_DIFFERENTIALS__
+ ray->dP = sd->dP;
+#endif
+
+ /* enter/exit volume */
+ kernel_volume_stack_enter_exit(kg, sd, state->volume_stack);
+ return true;
+ }
+#endif
+ else {
+ /* no bsdf or volume? */
+ return false;
+ }
+}
+
+CCL_NAMESPACE_END
+
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-06 12:35:03 +0300