SUMMARY:

Freestyle's pipeline is now fully controllable at the layer level. It can be used:
 - in any render layer
 - with as many style modules per layer

DETAILS:
Freestyle usage has not changed:
  - all the configuration happens in the "Freestyle" render panel, after it is enabled in the "Output" panel with the 'Freestyle' toggle.
  - each render layer can choose to render Freestyle strokes by togglingo on 'FrSt' (in the "Render Layers" panel)
  - it is fully compatible with compositor nodes

In the "Freestyle" panel, a render layer is selected via the menu list next to the "Render Layer:" label. The options displayed below are those of the currently selected render layer (and are not global to all render layers, as was previously the case).

Style modules are added by pressing the lower button "Add style module". Once added, the following operations are possible:
- deletion (cross)
- reordering (up/down arrows)
- toggling of display (check)

The order of the style modules follows Freestyle's original convention: the modules in the list from top to bottom are respectively the first to the last composited in the render layer. For example, if the module list is "contour" followed by "cartoon", the "cartoon" strokes are rendered on top of the "contour" strokes.

The "Freestyle" panel is constantly synchronized with the "Render Layers" panel: if render layers are added, deleted or toggled off display, Freestyle will take note of the changes.

The current pipeline works as follows:

----------------------------------------------------------------------------------------------
for every scene that is being rendered
	if Freestyle is enabled globally
	
		Freestyle is initialized
		camera and view settings are transferred from Blender to Freestyle
		
		for every render layer
			if: - layer is enabled 
			    - layer enabled Freestyle
			    - the number of displayed style modules is non-zero
				
				canvas is cleared
				geometry is transferred from Blender to Freestyle
				settings are fixed for current iteration
				view map is calculated
				
				strokes are computed in the canvas (based on view map and style modules)
				strokes are rendered in separate Blender scene
				
				scene is composited in current layer
----------------------------------------------------------------------------------------------

A number of changes were made on the codebase:
- the rendering interface between Freestyle and Blender was simplified. The following naming convention was used: functions that are called from within Blender pipeline are prefixed with 'FRS_', while the variables are prefixed with 'freestyle_'
- Freestyle data structures that were put in Blender's render pipeline were removed
- Freestyle cleans up its data structures on Blender exit and shouldn't leak memory
- to ease the configuration in the "Freestyle" panel, a centralized configuration data structure was used and can be easily extended

LIMITATIONS
Even though the current commit is stable and achieves the intended result, it is not as efficient as it could be:
- the canvas and the style modules are at cleared at each layer-level render
- geometry is reloaded at each frame and is duplicated across render layers

This revision clarifies my understanding of the future role of the view map in the compositor. Unfortunately, contrary to what the original proposal said, it is impossible to provide the view map as a render pass because render passes are defined (RE_pipeline.h) as raw floating-point rects. We will have to determine whether or not to extend the notion of render pass to fully integrate the view map in the compositor.

9 files changed, 254 insertions, 106 deletions

diff --git a/source/blender/freestyle/intern/app_blender/Controller.cpp b/source/blender/freestyle/intern/app_blender/Controller.cpp
index 8c00dd9b3f3..f960b749ce6 100755
--- a/source/blender/freestyle/intern/app_blender/Controller.cpp
+++ b/source/blender/freestyle/intern/app_blender/Controller.cpp
@@ -175,10 +175,10 @@ void Controller::setView(AppView *iView)
   _Canvas->setViewer(_pView);
 }
 
-int Controller::LoadMesh(Render *re)
+int Controller::LoadMesh(Render *re, SceneRenderLayer* srl)
 {
   
-  BlenderFileLoader loader(re);
+  BlenderFileLoader loader(re, srl);
   
   _Chrono.start();
   
@@ -640,11 +640,12 @@ void Controller::DrawStrokes()
   resetModified();
 }
 
-void Controller::RenderBlender(Render *re) {
+Render* Controller::RenderStrokes(Render *re) {
 	BlenderStrokeRenderer* blenderRenderer = new BlenderStrokeRenderer;
   	_Canvas->Render( blenderRenderer );
-	blenderRenderer->RenderScene(re);
+	Render* freestyle_render = blenderRenderer->RenderScene(re);
 	blenderRenderer->Close();
+	return freestyle_render;
 }
 
 void Controller::InsertStyleModule(unsigned index, const char *iFileName)
diff --git a/source/blender/freestyle/intern/app_blender/Controller.h b/source/blender/freestyle/intern/app_blender/Controller.h
index 84c50061d7c..46d08d0c686 100755
--- a/source/blender/freestyle/intern/app_blender/Controller.h
+++ b/source/blender/freestyle/intern/app_blender/Controller.h
@@ -57,6 +57,7 @@ extern "C" {
 #endif
 
 	#include "render_types.h"
+	#include "DNA_scene_types.h"
 
 #ifdef __cplusplus
 }
@@ -73,15 +74,15 @@ public:
   //soc
 	void init_options();
 
-	int  LoadMesh( Render *re );
+  int  LoadMesh( Render *re, SceneRenderLayer* srl );
   int  Load3DSFile(const char *iFileName);
   void CloseFile();
   void ComputeViewMap();
   void ComputeSteerableViewMap();
   void saveSteerableViewMapImages();
   void toggleEdgeTesselationNature(Nature::EdgeNature iNature);
-  void RenderBlender(Render *re);
-	void DrawStrokes();
+  void DrawStrokes();
+  Render* RenderStrokes(Render *re);
   void SwapStyleModules(unsigned i1, unsigned i2);
   void InsertStyleModule(unsigned index, const char *iFileName);
   void AddStyleModule(const char *iFileName);
diff --git a/source/blender/freestyle/intern/app_blender/FRS_freestyle.cpp b/source/blender/freestyle/intern/app_blender/FRS_freestyle.cpp
index af9210205bd..74414fbc844 100644
--- a/source/blender/freestyle/intern/app_blender/FRS_freestyle.cpp
+++ b/source/blender/freestyle/intern/app_blender/FRS_freestyle.cpp
@@ -4,70 +4,108 @@
 #include "AppCanvas.h"
 
 #include <iostream>
+#include <map>
+#include <set>
+using namespace std;
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-#include "../../FRS_freestyle.h"
+#include "MEM_guardedalloc.h"
 
 #include "DNA_camera_types.h"
+#include "DNA_listBase.h"
 #include "DNA_scene_types.h"
 
-#include "render_types.h"
-#include "renderpipeline.h"
-#include "pixelblending.h"
-
+#include "BKE_global.h"
 #include "BLI_blenlib.h"
 #include "BIF_renderwin.h"
 #include "BPY_extern.h"
 
-#ifdef __cplusplus
-}
-#endif
-
-using namespace std;
+#include "render_types.h"
+#include "renderpipeline.h"
+#include "pixelblending.h"
 
-#ifdef __cplusplus
-extern "C" {
-#endif
+#include "../../FRS_freestyle.h"
 
+	// Freestyle configuration
+	short freestyle_is_initialized = 0;
 	static Config::Path *pathconfig = NULL;
 	static Controller *controller = NULL;
 	static AppView *view = NULL;
 
-	char style_module[255] = "";
-	int freestyle_flags;
-	float freestyle_sphere_radius = 1.0;
-	float freestyle_dkr_epsilon = 0.001;
-	
+	// camera information
 	float freestyle_viewpoint[3];
 	float freestyle_mv[4][4];
 	float freestyle_proj[4][4];
 	int freestyle_viewport[4];
+	
+	// Panel configuration
+	short freestyle_current_layer_number = 0;
+	char* freestyle_current_module_path = NULL;
+	SceneRenderLayer* freestyle_current_layer = NULL;
+
+	ListBase* freestyle_modules;
+	int* freestyle_flags;
+	float* freestyle_sphere_radius;
+	float* freestyle_dkr_epsilon;
+	
+	class FreestylePanelConfigurationData {
+	public:
+		set<SceneRenderLayer*> layers;
+		map<SceneRenderLayer*, ListBase*> modules;
+		map<SceneRenderLayer*, int*> flags;
+		map<SceneRenderLayer*, float*> sphere_radius;
+		map<SceneRenderLayer*, float*> dkr_epsilon;
+		
+		FreestylePanelConfigurationData() {}
+		~FreestylePanelConfigurationData() {
+			set<SceneRenderLayer*>::iterator it;
+			
+			for( it=layers.begin(); it!=layers.end(); it++)
+				FRS_delete_layer( *it, 1 );
+		}
+	};
+	static FreestylePanelConfigurationData* panelConfig;
+	
+	string default_module_path;
+
+	//=======================================================
+	//   Initialization 
+	//=======================================================
 
 	void FRS_initialize(){
 		
-		if( pathconfig == NULL )
+		if( !freestyle_is_initialized ) {
+
 			pathconfig = new Config::Path;
-		
-		if( controller == NULL )
 			controller = new Controller;
-		
-		if( view == NULL ) {
 			view = new AppView;
 			controller->setView(view);
+			
+			panelConfig = new FreestylePanelConfigurationData;
+			
+			default_module_path = pathconfig->getProjectDir() + Config::DIR_SEP + "style_modules" + Config::DIR_SEP + "contour.py";
+			FRS_select_layer( (SceneRenderLayer*) BLI_findlink(&G.scene->r.layers, G.scene->r.actlay) );
+			
+			freestyle_is_initialized = 1;
 		}
 		
-		if( strlen(style_module) == 0 ){
-			string path( pathconfig->getProjectDir() +  Config::DIR_SEP + "style_modules" + Config::DIR_SEP + "contour.py" );
-			strcpy( style_module, path.c_str() );
-		}
-		
+	}
+	
+	void FRS_exit() {
+		delete pathconfig;
+		delete controller;
+		delete view;
+		delete panelConfig;
 	}
 
+	//=======================================================
+	//   Rendering 
+	//=======================================================
 
-	void FRS_init_view(Render* re){
+	void init_view(Render* re){
 		int width = re->scene->r.xsch;
 		int height = re->scene->r.ysch;
 		
@@ -79,7 +117,7 @@ extern "C" {
 		view->setHeight( height );
 	}
 
-	void FRS_init_camera(Render* re){
+	void init_camera(Render* re){
 		Object* maincam_obj = re->scene->camera;
 		Camera *cam = (Camera*) maincam_obj->data;
 
@@ -115,29 +153,34 @@ extern "C" {
 	}
 
 	
-	void FRS_prepare(Render* re) {
+	void prepare(Render* re, SceneRenderLayer* srl ) {
 		
-		// init
-		FRS_initialize();
-		FRS_init_view(re);
-		FRS_init_camera(re);
+		// clear canvas
 		controller->Clear();
 
 		// load mesh
-		if( controller->LoadMesh(re) ) // returns if scene cannot be loaded or if empty
+		if( controller->LoadMesh(re, srl) ) // returns if scene cannot be loaded or if empty
 			return;
 		
-		// add style module
-			cout << "\n===  Rendering options  ===" << endl;
-		cout << "Module: " << style_module << endl;
-		controller->InsertStyleModule( 0, style_module );
-		controller->toggleLayer(0, true);
+		// add style modules
+		cout << "\n===  Rendering options  ===" << endl;
+		cout << "Modules :"<< endl;
+		int layer_count = 0;
+		for( StyleModuleConf* module_conf = (StyleModuleConf *)panelConfig->modules[srl]->first; module_conf; module_conf = module_conf->next ) {
+			if( module_conf->is_displayed ) {
+				cout << "  " << layer_count+1 << ": " << module_conf->module_path << endl;
+				controller->InsertStyleModule( layer_count, module_conf->module_path );
+				controller->toggleLayer(layer_count, true);
+				layer_count++;
+			}
+		}	
+		cout << endl;
 		
 		// set parameters
-		controller->setSphereRadius(freestyle_sphere_radius);
-		controller->setComputeRidgesAndValleysFlag((freestyle_flags & FREESTYLE_RIDGES_AND_VALLEYS_FLAG) ? true : false);
-		controller->setComputeSuggestiveContoursFlag((freestyle_flags & FREESTYLE_SUGGESTIVE_CONTOURS_FLAG) ? true : false);
-		controller->setSuggestiveContourKrDerivativeEpsilon(freestyle_dkr_epsilon);
+		controller->setSphereRadius(*panelConfig->sphere_radius[srl]);
+		controller->setComputeRidgesAndValleysFlag((*panelConfig->flags[srl] & FREESTYLE_RIDGES_AND_VALLEYS_FLAG) ? true : false);
+		controller->setComputeSuggestiveContoursFlag((*panelConfig->flags[srl] & FREESTYLE_SUGGESTIVE_CONTOURS_FLAG) ? true : false);
+		controller->setSuggestiveContourKrDerivativeEpsilon(*panelConfig->dkr_epsilon[srl]);
 
 		cout << "Sphere radius : " << controller->getSphereRadius() << endl;
 		cout << "Redges and valleys : " << (controller->getComputeRidgesAndValleysFlag() ? "enabled" : "disabled") << endl;
@@ -148,33 +191,17 @@ extern "C" {
 		controller->ComputeViewMap();
 	}
 	
-	void FRS_render_Blender(Render* re) {
-		
-		if( controller->_ViewMap ) {
-			cout << "\n===  Rendering Freestyle with Blender's internal renderer  ===" << endl;
-			
-			// build strokes
-			controller->DrawStrokes();
-
-			controller->RenderBlender(re);
-			controller->CloseFile();
-		} else {
-			cout << "Freestyle cannot be used because the view map is not available" << endl;
-		}
-		cout << "\n###################################################################" << endl;
-	}
-	
-	void FRS_composite_result(Render* re, SceneRenderLayer* srl)
+	void composite_result(Render* re, SceneRenderLayer* srl, Render* freestyle_render)
 	{
 
 		RenderLayer *rl;
 	    float *src, *dest, *pixSrc, *pixDest;
 		int x, y, rectx, recty;
 		
-		if( re->freestyle_render == NULL || re->freestyle_render->result == NULL )
+		if( freestyle_render == NULL || freestyle_render->result == NULL )
 			return;
 
-		rl = render_get_active_layer( re->freestyle_render, re->freestyle_render->result );
+		rl = render_get_active_layer( freestyle_render, freestyle_render->result );
 	    if( !rl || rl->rectf == NULL) { cout << "Cannot find Freestyle result image" << endl; return; }
 		src  = rl->rectf;
 		
@@ -198,21 +225,150 @@ extern "C" {
 		
 	}
 	
+	int displayed_layer_count( SceneRenderLayer* srl ) {
+		int count = 0;
+
+		for( StyleModuleConf* module_conf = (StyleModuleConf *)panelConfig->modules[srl]->first; module_conf; module_conf = module_conf->next ) {
+			if( module_conf->is_displayed )
+				count++;
+		}
+		return count;
+	}
+	
 	void FRS_add_Freestyle(Render* re) {
 		
-		SceneRenderLayer *srl, *freestyle_srl = NULL;
-		for(srl= (SceneRenderLayer *)re->scene->r.layers.first; srl && (freestyle_srl == NULL); srl= srl->next) {
-			if(srl->layflag & SCE_LAY_FRS) {
-				if (!freestyle_srl) freestyle_srl = srl;
+		SceneRenderLayer *srl;
+		Render* freestyle_render = NULL;
+		
+		// init
+		cout << "\n#===============================================================" << endl;
+		cout << "#  Freestyle" << endl;
+		cout << "#===============================================================" << endl;
+		
+		FRS_initialize();
+		init_view(re);
+		init_camera(re);
+		
+		for(srl= (SceneRenderLayer *)re->scene->r.layers.first; srl; srl= srl->next) {
+			if( !(srl->layflag & SCE_LAY_DISABLE) &&
+			 	srl->layflag & SCE_LAY_FRS &&
+				displayed_layer_count(srl) > 0       )
+			{
+				cout << "\n----------------------------------------------------------" << endl;
+				cout << "|  "<< srl->name << endl;
+				cout << "----------------------------------------------------------" << endl;
+				
+				// prepare Freestyle:
+				//   - clear canvas
+				//   - load mesh
+				//   - add style modules
+				//   - set parameters
+				//   - compute view map
+				prepare(re, srl);
+
+				// render and composite Freestyle result
+				if( controller->_ViewMap ) {
+					
+					// render strokes					
+					controller->DrawStrokes();
+					freestyle_render = controller->RenderStrokes(re);
+					controller->CloseFile();
+					
+					// composite result
+					composite_result(re, srl, freestyle_render);
+					
+					// free resources
+					RE_FreeRender(freestyle_render);
+				}
 			}
 		}
 		
-		if( freestyle_srl ) {
-			FRS_prepare(re);
-			FRS_render_Blender(re);
-			FRS_composite_result(re, freestyle_srl);
+	}
+
+	//=======================================================
+	//   Freestyle Panel Configuration
+	//=======================================================
+
+	void FRS_select_layer( SceneRenderLayer* srl )
+	{
+		if( panelConfig->layers.find(srl) == panelConfig->layers.end() )
+		{
+			panelConfig->layers.insert(srl);
+			
+			panelConfig->modules[srl] = new ListBase;
+			panelConfig->modules[srl]->first = panelConfig->modules[srl]->last = NULL;
+			
+			panelConfig->flags[srl] = new int(0);
+			panelConfig->sphere_radius[srl] = new float(1.0);
+			panelConfig->dkr_epsilon[srl] = new float(0.001);
 		}
+		
+		freestyle_modules = panelConfig->modules[srl];
+		freestyle_flags = panelConfig->flags[srl];
+		freestyle_sphere_radius = panelConfig->sphere_radius[srl];
+		freestyle_dkr_epsilon = panelConfig->dkr_epsilon[srl];
+		
+		freestyle_current_layer = srl;
+		freestyle_current_layer_number = BLI_findindex(&G.scene->r.layers, freestyle_current_layer);
 	}
+
+	void FRS_delete_layer( SceneRenderLayer* srl, short isDestructor )
+	{
+		BLI_freelistN( panelConfig->modules[srl] );
+		delete panelConfig->modules[srl];
+		
+		delete panelConfig->flags[srl];
+		delete panelConfig->sphere_radius[srl];
+		delete panelConfig->dkr_epsilon[srl];
+		
+		panelConfig->modules.erase(srl);
+		panelConfig->flags.erase(srl);
+		panelConfig->sphere_radius.erase(srl);
+		panelConfig->dkr_epsilon.erase(srl);
+		
+		if( !isDestructor )
+			panelConfig->layers.erase(srl);
+	}
+	
+	void FRS_add_module()
+	{
+		StyleModuleConf* module_conf = (StyleModuleConf*) MEM_callocN( sizeof(StyleModuleConf), "style module configuration");
+		BLI_addtail(freestyle_modules, (void*) module_conf);
+		
+		strcpy( module_conf->module_path, default_module_path.c_str() );
+		module_conf->is_displayed = 1;	
+	}
+	
+	void FRS_delete_module(void *module_index_ptr, void *unused)
+	{
+		StyleModuleConf* module_conf = (StyleModuleConf*) BLI_findlink(freestyle_modules, (intptr_t)module_index_ptr);
+
+		BLI_freelinkN( freestyle_modules, module_conf);
+	}
+	
+	void FRS_move_up_module(void *module_index_ptr, void *unused)
+	{
+		StyleModuleConf* module_conf = (StyleModuleConf*) BLI_findlink(freestyle_modules, (intptr_t)module_index_ptr);
+		
+		BLI_remlink(freestyle_modules, module_conf);
+		BLI_insertlink(freestyle_modules, module_conf->prev->prev, module_conf);
+	}
+	
+	void FRS_move_down_module(void *module_index_ptr, void *unused)
+	{			
+		StyleModuleConf* module_conf = (StyleModuleConf*) BLI_findlink(freestyle_modules, (intptr_t)module_index_ptr);
+		
+		BLI_remlink(freestyle_modules, module_conf);
+		BLI_insertlink(freestyle_modules, module_conf->next, module_conf);
+	}
+	
+	void FRS_set_module_path(void *module_index_ptr, void *unused)
+	{
+		StyleModuleConf* module_conf = (StyleModuleConf*) BLI_findlink(freestyle_modules, (intptr_t)module_index_ptr);
+		freestyle_current_module_path = module_conf->module_path;
+	}
+	
+	
 	
 #ifdef __cplusplus
 }
diff --git a/source/blender/freestyle/intern/scene_graph/BlenderFileLoader.cpp b/source/blender/freestyle/intern/scene_graph/BlenderFileLoader.cpp
index d1713254ce7..4dc92755ad9 100644
--- a/source/blender/freestyle/intern/scene_graph/BlenderFileLoader.cpp
+++ b/source/blender/freestyle/intern/scene_graph/BlenderFileLoader.cpp
@@ -1,8 +1,9 @@
 #include "BlenderFileLoader.h"
 
-BlenderFileLoader::BlenderFileLoader(Render *re)
+BlenderFileLoader::BlenderFileLoader(Render *re, SceneRenderLayer* srl)
 {
 	_re = re;
+	_srl = srl;
   _Scene = NULL;
   _numFacesRead = 0;
   _minEdgeSize = DBL_MAX;
@@ -19,28 +20,13 @@ NodeGroup* BlenderFileLoader::Load()
 	ObjectRen *obr;
 
 	cout << "\n===  Importing triangular meshes into Blender  ===" << endl;
-	
-	SceneRenderLayer *srl, *active_srl = NULL;
-	int count = 0;
-	for(srl= (SceneRenderLayer *)_re->scene->r.layers.first; srl; srl= srl->next) {
-		if(srl->layflag & SCE_LAY_FRS) {
-			if (!active_srl) active_srl = srl;
-			count++;
-		}
-	}
-	if (count > 1) {
-		cout << "Warning: Freestyle is enabled in the following " << count << " scene render layers:" << endl;
-		for(srl= (SceneRenderLayer *)_re->scene->r.layers.first; srl; srl= srl->next)
-			if(srl->layflag & SCE_LAY_FRS)
-				cout << "  \"" << srl->name << "\"" << ((active_srl == srl) ? " (only this is taken into account)" : "") << endl;
-	}
 
   // creation of the scene root node
   _Scene = new NodeGroup;
 
 	int id = 0;
 	for(obi= (ObjectInstanceRen *) _re->instancetable.first; obi; obi=obi->next) {
-		if (!(obi->lay & _re->scene->lay & active_srl->lay))
+		if (!(obi->lay & _re->scene->lay & _srl->lay))
 			continue;
 
 		obr= obi->obr;
diff --git a/source/blender/freestyle/intern/scene_graph/BlenderFileLoader.h b/source/blender/freestyle/intern/scene_graph/BlenderFileLoader.h
index 8202c0e4716..ea5d9cb1a52 100644
--- a/source/blender/freestyle/intern/scene_graph/BlenderFileLoader.h
+++ b/source/blender/freestyle/intern/scene_graph/BlenderFileLoader.h
@@ -38,7 +38,7 @@ class LIB_SCENE_GRAPH_EXPORT BlenderFileLoader
 {
 public:
   /*! Builds a MaxFileLoader */
-	BlenderFileLoader(Render *re);
+	BlenderFileLoader(Render *re, SceneRenderLayer* srl);
   virtual ~BlenderFileLoader();
 
   /*! Loads the 3D scene and returns a pointer to the scene root node */
@@ -55,6 +55,7 @@ protected:
 
 protected:
 	Render* _re;
+	SceneRenderLayer* _srl;
   NodeGroup* _Scene;
   unsigned _numFacesRead;
   real _minEdgeSize;
diff --git a/source/blender/freestyle/intern/stroke/BlenderStrokeRenderer.cpp b/source/blender/freestyle/intern/stroke/BlenderStrokeRenderer.cpp
index 286d23c619b..6dc45300b9d 100644
--- a/source/blender/freestyle/intern/stroke/BlenderStrokeRenderer.cpp
+++ b/source/blender/freestyle/intern/stroke/BlenderStrokeRenderer.cpp
@@ -228,20 +228,16 @@ void BlenderStrokeRenderer::RenderStrokeRepBasic(StrokeRep *iStrokeRep) const{
 
 }
 
-void BlenderStrokeRenderer::RenderScene( Render *re ) {
+Render* BlenderStrokeRenderer::RenderScene( Render *re ) {
 	scene->r.mode &= ~( R_EDGE_FRS | R_SHADOW | R_SSS | R_PANORAMA | R_ENVMAP | R_MBLUR );
 	scene->r.scemode &= ~( R_SINGLE_LAYER );
 	scene->r.planes = R_PLANES32;
 	scene->r.imtype = R_PNG;
 	
-	re->freestyle_render = RE_NewRender(scene->id.name);
+	Render* freestyle_render = RE_NewRender(scene->id.name);
 	
-	RE_BlenderFrame( re->freestyle_render, scene, 1);
-
-	// char filepath[255];
-	// BLI_strncpy( filepath, "/Users/mx/Desktop/", sizeof(filepath) );
-	// strcat(filepath, "frs_result");
-	// BIF_save_rendered_image(filepath);
+	RE_BlenderFrame( freestyle_render, scene, 1);
+	return freestyle_render;
 }
 
 void BlenderStrokeRenderer::Close() {
diff --git a/source/blender/freestyle/intern/stroke/BlenderStrokeRenderer.h b/source/blender/freestyle/intern/stroke/BlenderStrokeRenderer.h
index 9f7d2d4cd19..03f365525ed 100644
--- a/source/blender/freestyle/intern/stroke/BlenderStrokeRenderer.h
+++ b/source/blender/freestyle/intern/stroke/BlenderStrokeRenderer.h
@@ -30,7 +30,7 @@ public:
   virtual void RenderStrokeRep(StrokeRep *iStrokeRep) const;
   virtual void RenderStrokeRepBasic(StrokeRep *iStrokeRep) const;
 
-	void RenderScene(Render *re);
+	Render* RenderScene(Render *re);
 	void Close();
 
 protected:
diff --git a/source/blender/freestyle/intern/stroke/Canvas.cpp b/source/blender/freestyle/intern/stroke/Canvas.cpp
index 10a704c304a..7be2b54a036 100755
--- a/source/blender/freestyle/intern/stroke/Canvas.cpp
+++ b/source/blender/freestyle/intern/stroke/Canvas.cpp
@@ -171,6 +171,12 @@ void Canvas::Erase()
 stroke_count = 0;
 }
 
+void Canvas::PushBackStyleModule(StyleModule *iStyleModule) {
+  StrokeLayer* layer = new StrokeLayer();
+  _StyleModules.push_back(iStyleModule);
+  _Layers.push_back(layer);
+}
+
 void Canvas::InsertStyleModule(unsigned index, StyleModule *iStyleModule) {
   unsigned size = _StyleModules.size();
   StrokeLayer* layer = new StrokeLayer();
diff --git a/source/blender/freestyle/intern/stroke/Canvas.h b/source/blender/freestyle/intern/stroke/Canvas.h
index b61e70099a8..707455c87f6 100755
--- a/source/blender/freestyle/intern/stroke/Canvas.h
+++ b/source/blender/freestyle/intern/stroke/Canvas.h
@@ -180,6 +180,7 @@ public:
   /*! modifiers */
   inline void setSelectedFEdge(FEdge *iFEdge) {_SelectedFEdge = iFEdge;}
   /*! inserts a shader at pos index+1 */
+  void PushBackStyleModule(StyleModule *iStyleModule);
   void InsertStyleModule(unsigned index, StyleModule *iStyleModule);
   void RemoveStyleModule(unsigned index);
   void SwapStyleModules(unsigned i1, unsigned i2);