soc-2008-mxcurioni: First render ! It should render the teapot upside down on a black background. The correction was made by following Yafray's rendering and display implementation, which is very clear.

source/blender/freestyle/intern/app_blender/api.cpp

@@ -6,13 +6,26 @@
 
 #include <iostream>
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "render_types.h"
+//#include "renderdatabase.h"
+/* display_draw() needs render layer info */
+#include "renderpipeline.h"
+
+#ifdef __cplusplus
+}
+#endif
+
 using namespace std;
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-	void FRS_execute() {
+	void FRS_execute(Render* re) {
 		cout << "Freestyle start" << endl;
 	
 		Config::Path pathconfig;
@@ -20,16 +33,39 @@ extern "C" {
 		AppGLWidget *view = new AppGLWidget;
 		
 		c->SetView(view);
-		view->setWidth(640);
-		view->setHeight(640);
+		unsigned int width = re->winx;
+		unsigned int height = re->winy;
+		view->setWidth(width);
+		view->setHeight(height);
 		
 		c->Load3DSFile( TEST_3DS_FILE );
 		
 		c->InsertStyleModule( 0, TEST_STYLE_MODULE_FILE );
 		c->toggleLayer(0, true);
 		c->ComputeViewMap();
-		 
+		
 		c->DrawStrokes();
+
+		RenderResult rres;
+		RE_GetResultImage(re, &rres);
+		float *rgb = new float[3*width*height];
+		view->readPixels(0,0,width,height,AppGLWidget::RGB, rgb);
+		
+		for (unsigned short y=0; y<height; y++) {
+			float* bpt = (float*)rres.rectf + ((y*width) << 2);			
+			for (unsigned short x=0; x<width; x++) {
+				float *pos = rgb + 3 * ( y*width + x );
+				
+				bpt[0] = pos[0]; // r
+				bpt[1] = pos[1]; // g
+				bpt[2] = pos[2]; // b
+				bpt[3] = 1.0; // a
+				bpt += 4;
+			}
+		}
+		
+		re->result->renlay = render_get_active_layer(re, re->result);
+		re->display_draw(re->result, NULL);
 		
 		cout << "Freestyle end" << endl;