Remove automatic full-cache invalidation on LUT processor change

InvalidateAll() on the OCIO LUT node caused the preview autocacher to
re-render the entire timeline, freezing the UI when switching LUT files.
Instead, let the new processor be used naturally on the next render
request (scrubbing/playback).

app/node/color/ociolut/ociolut.cpp

@@ -20,7 +20,6 @@
 
 #include "ociolut.h"
 
-#include <QCoreApplication>
 #include <QFileInfo>
 #include <QMetaObject>
 
@@ -208,15 +207,10 @@ void OCIOLutNode::SetProcessorResult(ColorProcessorPtr processor,
 	last_processor_ = processor;
 	set_processor(processor);
 
-	// The processor has changed. In the main GUI process we need to invalidate
+	// NOTE: We intentionally do NOT call InvalidateAll() here. A full cache
-	// cached frames so the viewer refreshes automatically. In the render worker
+	// invalidation of the entire timeline freezes the UI while the preview
-	// process, a full invalidation can trigger an expensive re-cache of the
+	// autocacher re-renders every frame. The new processor will be picked up
-	// entire timeline, so we skip it; the next render request will naturally
+	// naturally on the next render request (e.g. scrubbing or playback).
-	// pick up the new processor.
-	if (QCoreApplication::applicationName() !=
-		QStringLiteral("olive-render-worker")) {
-		InvalidateAll(kTextureInput);
-	}
 }
 
 OCIOLutNode::GenerateProcessorTask::GenerateProcessorTask(