Fix T52653: Render output of linked scenes conflicts with other scenes with the same name

The issue was caused by render result identifier only consist of scene name,
which could indeed cause conflicts.

On the one hand, there are quite some areas in Blender where we need identifier
to be unique to properly address things. Usually this is required for sub-data
of IDs, like bones. On another hand, it's not that hard to support this
particular case and avoid possible frustration.

The idea is, we add library name to render identifier for linked scenes. We use
library name and not pointer so we preserve render results through undo stack.

Reviewers: campbellbarton, mont29, brecht

Reviewed By: mont29

Differential Revision: https://developer.blender.org/D2836

3 files changed, 9 insertions, 4 deletions

diff --git a/source/blender/compositor/operations/COM_CompositorOperation.cpp b/source/blender/compositor/operations/COM_CompositorOperation.cpp
index 76f74c144f6..15ffff2fc90 100644
--- a/source/blender/compositor/operations/COM_CompositorOperation.cpp
+++ b/source/blender/compositor/operations/COM_CompositorOperation.cpp
@@ -51,6 +51,7 @@ CompositorOperation::CompositorOperation() : NodeOperation()
 	this->m_useAlphaInput = false;
 	this->m_active = false;
 
+	this->m_scene = NULL;
 	this->m_sceneName[0] = '\0';
 	this->m_viewName = NULL;
 }
@@ -78,7 +79,7 @@ void CompositorOperation::deinitExecution()
 		return;
 
 	if (!isBreaked()) {
-		Render *re = RE_GetRender(this->m_sceneName);
+		Render *re = RE_GetSceneRender(this->m_scene);
 		RenderResult *rr = RE_AcquireResultWrite(re);
 
 		if (rr) {
@@ -217,7 +218,7 @@ void CompositorOperation::determineResolution(unsigned int resolution[2], unsign
 
 	// check actual render resolution with cropping it may differ with cropped border.rendering
 	// FIX for: [31777] Border Crop gives black (easy)
-	Render *re = RE_GetRender(this->m_sceneName);
+	Render *re = RE_GetSceneRender(this->m_scene);
 	if (re) {
 		RenderResult *rr = RE_AcquireResultRead(re);
 		if (rr) {
diff --git a/source/blender/compositor/operations/COM_CompositorOperation.h b/source/blender/compositor/operations/COM_CompositorOperation.h
index e81ba520695..269a065a793 100644
--- a/source/blender/compositor/operations/COM_CompositorOperation.h
+++ b/source/blender/compositor/operations/COM_CompositorOperation.h
@@ -26,11 +26,14 @@
 #include "BLI_rect.h"
 #include "BLI_string.h"
 
+struct Scene;
+
 /**
  * @brief Compositor output operation
  */
 class CompositorOperation : public NodeOperation {
 private:
+	const struct Scene *m_scene;
 	/**
 	 * @brief Scene name, used for getting the render output, includes 'SC' prefix.
 	 */
@@ -84,6 +87,7 @@ public:
 	CompositorOperation();
 	const bool isActiveCompositorOutput() const { return this->m_active; }
 	void executeRegion(rcti *rect, unsigned int tileNumber);
+	void setScene(const struct Scene *scene) { m_scene = scene; }
 	void setSceneName(const char *sceneName) { BLI_strncpy(this->m_sceneName, sceneName, sizeof(this->m_sceneName)); }
 	void setViewName(const char *viewName) { this->m_viewName = viewName; }
 	void setRenderData(const RenderData *rd) { this->m_rd = rd; }
diff --git a/source/blender/compositor/operations/COM_RenderLayersProg.cpp b/source/blender/compositor/operations/COM_RenderLayersProg.cpp
index 26654b31e16..d1c654ddb6c 100644
--- a/source/blender/compositor/operations/COM_RenderLayersProg.cpp
+++ b/source/blender/compositor/operations/COM_RenderLayersProg.cpp
@@ -48,7 +48,7 @@ RenderLayersProg::RenderLayersProg(const char *passName, DataType type, int elem
 void RenderLayersProg::initExecution()
 {
 	Scene *scene = this->getScene();
-	Render *re = (scene) ? RE_GetRender(scene->id.name) : NULL;
+	Render *re = (scene) ? RE_GetSceneRender(scene) : NULL;
 	RenderResult *rr = NULL;
 	
 	if (re)
@@ -179,7 +179,7 @@ void RenderLayersProg::deinitExecution()
 void RenderLayersProg::determineResolution(unsigned int resolution[2], unsigned int /*preferredResolution*/[2])
 {
 	Scene *sce = this->getScene();
-	Render *re = (sce) ? RE_GetRender(sce->id.name) : NULL;
+	Render *re = (sce) ? RE_GetSceneRender(sce) : NULL;
 	RenderResult *rr = NULL;
 	
 	resolution[0] = 0;