diff options
| author | Lukas Stockner <lukas.stockner@freenet.de> | 2016-06-08 04:17:19 +0300 |
|---|---|---|
| committer | Jeroen Bakker <j.bakker@atmind.nl> | 2016-06-08 22:45:40 +0300 |
| commit | 74c65981ceb55ed8007be2ee8fd1dd7624c29b0c (patch) | |
| tree | 00851ce4727adc4621573079b1a1bb5e1da77620 | |
| parent | b5a9434a29a19e214c2fee8427351392620f3762 (diff) | |
Cycles: Fix two numerical issues in the volume code
This hopefully fixes T48383 by avoiding two numerical problems that I found in the volume code.
Reviewers: sergey, dingto, brecht
Reviewed By: sergey, dingto, brecht
Maniphest Tasks: T48383
Differential Revision: https://developer.blender.org/D2051
| -rw-r--r-- | intern/cycles/kernel/kernel_volume.h | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/intern/cycles/kernel/kernel_volume.h b/intern/cycles/kernel/kernel_volume.h index 0e313b8e88c..bf8301fe5fb 100644 --- a/intern/cycles/kernel/kernel_volume.h +++ b/intern/cycles/kernel/kernel_volume.h @@ -276,7 +276,7 @@ ccl_device float kernel_volume_distance_sample(float max_t, float3 sigma_t, int float sample_t = min(max_t, -logf(1.0f - xi*(1.0f - sample_transmittance))/sample_sigma_t); *transmittance = volume_color_transmittance(sigma_t, sample_t); - *pdf = (sigma_t * *transmittance)/(make_float3(1.0f, 1.0f, 1.0f) - full_transmittance); + *pdf = safe_divide_color(sigma_t * *transmittance, make_float3(1.0f, 1.0f, 1.0f) - full_transmittance); /* todo: optimization: when taken together with hit/miss decision, * the full_transmittance cancels out drops out and xi does not @@ -290,7 +290,7 @@ ccl_device float3 kernel_volume_distance_pdf(float max_t, float3 sigma_t, float float3 full_transmittance = volume_color_transmittance(sigma_t, max_t); float3 transmittance = volume_color_transmittance(sigma_t, sample_t); - return (sigma_t * transmittance)/(make_float3(1.0f, 1.0f, 1.0f) - full_transmittance); + return safe_divide_color(sigma_t * transmittance, make_float3(1.0f, 1.0f, 1.0f) - full_transmittance); } /* Emission */ @@ -625,11 +625,13 @@ ccl_device void kernel_volume_decoupled_record(KernelGlobals *kg, PathState *sta const int global_max_steps = kernel_data.integrator.volume_max_steps; step_size = kernel_data.integrator.volume_step_size; /* compute exact steps in advance for malloc */ - max_steps = max((int)ceilf(ray->t/step_size), 1); - if(max_steps > global_max_steps) { + if(ray->t > global_max_steps*step_size) { max_steps = global_max_steps; step_size = ray->t / (float)max_steps; } + else { + max_steps = max((int)ceilf(ray->t/step_size), 1); + } #ifdef __KERNEL_CPU__ /* NOTE: For the branched path tracing it's possible to have direct * and indirect light integration both having volume segments allocated. |