Cycles: perform clamping per light contribution instead of whole path

With upcoming light group passes, for them to sum up correctly to the combined
pass the clamping must be more fine grained.

This also has the advantage that if one light is particularly noisy, it does
not diminish the contribution from other lights which do not need as much
clamping.

Clamp values on existing scenes will need to be tweaked to get similar results,
there is no automatic conversion possible which would give the same results as
before.

Implemented by Lukas, with tweaks by Brecht.

Part of D4837

4 files changed, 4 insertions, 5 deletions

diff --git a/intern/cycles/kernel/split/kernel_branched.h b/intern/cycles/kernel/split/kernel_branched.h
index e08d87ab618..bfcd21baac4 100644
--- a/intern/cycles/kernel/split/kernel_branched.h
+++ b/intern/cycles/kernel/split/kernel_branched.h
@@ -106,7 +106,7 @@ ccl_device_inline bool kernel_split_branched_indirect_start_shared(KernelGlobals
   PathRadiance *L = &kernel_split_state.path_radiance[ray_index];
   PathRadiance *inactive_L = &kernel_split_state.path_radiance[inactive_ray];
 
-  path_radiance_init(inactive_L, kernel_data.film.use_light_pass);
+  path_radiance_init(kg, inactive_L);
   path_radiance_copy_indirect(inactive_L, L);
 
   ray_state[inactive_ray] = RAY_REGENERATED;
diff --git a/intern/cycles/kernel/split/kernel_buffer_update.h b/intern/cycles/kernel/split/kernel_buffer_update.h
index e37be5b405e..dba1768f03f 100644
--- a/intern/cycles/kernel/split/kernel_buffer_update.h
+++ b/intern/cycles/kernel/split/kernel_buffer_update.h
@@ -135,7 +135,7 @@ ccl_device void kernel_buffer_update(KernelGlobals *kg,
            * These rays proceed with path-iteration.
            */
           *throughput = make_float3(1.0f, 1.0f, 1.0f);
-          path_radiance_init(L, kernel_data.film.use_light_pass);
+          path_radiance_init(kg, L);
           path_state_init(kg,
                           AS_SHADER_DATA(&kernel_split_state.sd_DL_shadow[ray_index]),
                           state,
diff --git a/intern/cycles/kernel/split/kernel_path_init.h b/intern/cycles/kernel/split/kernel_path_init.h
index 3faa3208341..82b0f583d8d 100644
--- a/intern/cycles/kernel/split/kernel_path_init.h
+++ b/intern/cycles/kernel/split/kernel_path_init.h
@@ -59,8 +59,7 @@ ccl_device void kernel_path_init(KernelGlobals *kg)
      * These rays proceed with path-iteration.
      */
     kernel_split_state.throughput[ray_index] = make_float3(1.0f, 1.0f, 1.0f);
-    path_radiance_init(&kernel_split_state.path_radiance[ray_index],
-                       kernel_data.film.use_light_pass);
+    path_radiance_init(kg, &kernel_split_state.path_radiance[ray_index]);
     path_state_init(kg,
                     AS_SHADER_DATA(&kernel_split_state.sd_DL_shadow[ray_index]),
                     &kernel_split_state.path_state[ray_index],
diff --git a/intern/cycles/kernel/split/kernel_shadow_blocked_dl.h b/intern/cycles/kernel/split/kernel_shadow_blocked_dl.h
index 82990ce9fae..5e46d300bca 100644
--- a/intern/cycles/kernel/split/kernel_shadow_blocked_dl.h
+++ b/intern/cycles/kernel/split/kernel_shadow_blocked_dl.h
@@ -87,7 +87,7 @@ ccl_device void kernel_shadow_blocked_dl(KernelGlobals *kg)
 
     if (!shadow_blocked(kg, sd, emission_sd, state, &ray, &shadow)) {
       /* accumulate */
-      path_radiance_accum_light(L, state, throughput, &L_light, shadow, 1.0f, is_lamp);
+      path_radiance_accum_light(kg, L, state, throughput, &L_light, shadow, 1.0f, is_lamp);
     }
     else {
       path_radiance_accum_total_light(L, state, throughput, &L_light);