Merge pull request #346 from aws-lumberyard-dev/Atom/santorac/DynamicMaterialTestShaderVariantTimingFailure

Fixed a random failure in the DynamicMaterialTest script.

Gem/Code/Source/DynamicMaterialTestComponent.cpp

@@ -302,7 +302,11 @@ namespace AtomSampleViewer
         if (updateMaterials)
         {
             m_materialConfigs[m_currentMaterialConfig].m_updateLatticeMaterials();
-            CompileMaterials();
         }
+
+        // Even if materials weren't changed on this frame, they still might need to be compiled to apply changes
+        // from a previous frame. This could be the result of a material that was just loaded or reinitialized on
+        // the previous frame, possibly caused by a shader variant hot-loading.
+        CompileMaterials();
     }
 } // namespace AtomSampleViewer

Scripts/DynamicMaterialTest.bv.lua

@@ -31,18 +31,21 @@ function TakeScreenshotSeries(filenamePrefix)
     SelectImageComparisonToleranceLevel("Level H")
 
     -- There could be variation in how long prior activities took so reset the clock for each series of screenshots
-    SetImguiValue('Reset Clock', true) 
-    IdleFrames(1) -- Give time for the sample to make any material changes before starting screenshots.
+    SetImguiValue('Reset Clock', true)     
+    IdleFrames(1) -- Consume ImGui changes, to ensure the clock is reset before pausing
 
     -- Note we pause while taking the screenshot so that IO delays won't impact the timing of the sample
 
     SetImguiValue("Pause", true)
+    IdleFrames(1) -- Give extra time to make sure any material changes are applied, especially in case an asset hot-load causes the material to reinitialize itself.
     CaptureScreenshot(g_screenshotOutputFolder .. filenamePrefix .. '_A.png')
     SetImguiValue("Pause", false)
 
+    -- Let the animation run for 1 second
     IdleSeconds(1.0)
 
     SetImguiValue("Pause", true)
+    IdleFrames(1) -- Give extra time to make sure any material changes are applied, especially in case an asset hot-load causes the material to reinitialize itself.
     CaptureScreenshot(g_screenshotOutputFolder .. filenamePrefix .. '_B.png')
     SetImguiValue("Pause", false)
 end