[Bf-blender-cvs] [ac9ebc9de31] blender-v3.2-release: Fix Cycles division by zero in material preview render

[Brecht Van Lommel]

Commit: ac9ebc9de31fc923f3e867e6741298a1e1eb175f
Author: Brecht Van Lommel
Date:   Wed May 4 19:46:13 2022 +0200
Branches: blender-v3.2-release
https://developer.blender.org/rBac9ebc9de31fc923f3e867e6741298a1e1eb175f

Fix Cycles division by zero in material preview render

If the render gets cancelled before the first sample finishes.

===================================================================

M	intern/cycles/integrator/render_scheduler.cpp

===================================================================

diff --git a/intern/cycles/integrator/render_scheduler.cpp b/intern/cycles/integrator/render_scheduler.cpp
index a75662c90d8..ebc3170393f 100644
--- a/intern/cycles/integrator/render_scheduler.cpp
+++ b/intern/cycles/integrator/render_scheduler.cpp
@@ -750,6 +750,11 @@ double RenderScheduler::guess_display_update_interval_in_seconds_for_num_samples
 int RenderScheduler::calculate_num_samples_per_update() const
 {
   const double time_per_sample_average = path_trace_time_.get_average();
+  /* Fall back to 1 sample if we have not recorded a time yet. */
+  if (time_per_sample_average == 0.0) {
+    return 1;
+  }
+
   const double num_samples_in_second = pixel_size_ * pixel_size_ / time_per_sample_average;
 
   const double update_interval_in_seconds = guess_display_update_interval_in_seconds();