Made an attempt to improve memory consumption during stroke

rendering.  When objects exists out of the viewing frustrum and
near the near clipping plane, feature edges in the 3D camera
coordinate system are projected to an extremely far location from
the camera view in the 2D image space.  These feature edges
result in very long strokes with a large number of stroke
vertices, which temporarily require a significant memory storage,
causing a fatal "out of memory" error.  This problem is partially
addressed by the changes in the present commit.

1 files changed, 111 insertions, 64 deletions

diff --git a/source/blender/freestyle/intern/blender_interface/BlenderStrokeRenderer.cpp b/source/blender/freestyle/intern/blender_interface/BlenderStrokeRenderer.cpp
index 2a29576a981..aa268e7a265 100644
--- a/source/blender/freestyle/intern/blender_interface/BlenderStrokeRenderer.cpp
+++ b/source/blender/freestyle/intern/blender_interface/BlenderStrokeRenderer.cpp
@@ -138,12 +138,52 @@ void BlenderStrokeRenderer::RenderStrokeRepBasic(StrokeRep *iStrokeRep) const{
 	  Strip::vertex_container::iterator v[3];
 	  StrokeVertexRep *svRep[3];
 	  Vec3r color[3];
-	  unsigned int face_index;
+	  unsigned int vertex_index;
+	  float width = freestyle_scene->r.xsch;
+	  float height = freestyle_scene->r.ysch;
+	  Vec2r p;
 	
 	  for(vector<Strip*>::iterator s=strips.begin(), send=strips.end();
 	  s!=send;
 	  ++s){		
 		
+	    Strip::vertex_container& strip_vertices = (*s)->vertices();
+		int strip_vertex_count = (*s)->sizeStrip();
+		int m, n, visible_faces, visible_segments;
+		bool visible;
+
+		// iterate over all vertices and count visible faces and strip segments
+		// (note: a strip segment is a series of visible faces, while two strip
+		// segments are separated by one or more invisible faces)
+		v[0] = strip_vertices.begin();
+	    v[1] = v[0]; ++(v[1]);
+	    v[2] = v[1]; ++(v[2]);
+		visible_faces = visible_segments = 0;
+		visible = false;
+	    for (n = 2; n < strip_vertex_count; n++)
+		{
+			svRep[0] = *(v[0]);
+			svRep[1] = *(v[1]);
+			svRep[2] = *(v[2]);
+			m = 0;
+			for (int j = 0; j < 3; j++) {
+				p = svRep[j]->point2d();
+				if (p[0] < 0.0 || p[0] > width || p[1] < 0.0 || p[1] > height)
+					m++;
+			}
+			if (m == 3) {
+				visible = false;
+			} else {
+				visible_faces++;
+				if (!visible)
+					visible_segments++;
+				visible = true;
+			}
+			++v[0]; ++v[1]; ++v[2];
+		}
+		if (visible_faces == 0)
+			continue;
+
 		// me = Mesh.New()
 		Object* object_mesh = add_object(freestyle_scene, OB_MESH);
 		Mesh* mesh = (Mesh *) object_mesh->data;
@@ -164,14 +204,12 @@ void BlenderStrokeRenderer::RenderStrokeRepBasic(StrokeRep *iStrokeRep) const{
 		object_mesh->actcol= object_mesh->totcol;
 #endif
 		
-		int strip_vertex_count = (*s)->sizeStrip();
-	
 		// vertices allocation
-		mesh->totvert = strip_vertex_count;
+		mesh->totvert = visible_faces + visible_segments * 2;
 		mesh->mvert = (MVert*) CustomData_add_layer( &mesh->vdata, CD_MVERT, CD_CALLOC, NULL, mesh->totvert);
 			
 		// faces allocation
-		mesh->totface = strip_vertex_count - 2;
+		mesh->totface = visible_faces;
 		mesh->mface = (MFace*) CustomData_add_layer( &mesh->fdata, CD_MFACE, CD_CALLOC, NULL, mesh->totface);
 		
 		// colors allocation  - me.vertexColors = True
@@ -185,75 +223,84 @@ void BlenderStrokeRenderer::RenderStrokeRepBasic(StrokeRep *iStrokeRep) const{
 		MFace* faces = mesh->mface;
 		MCol* colors = mesh->mcol;
 		
-	    Strip::vertex_container& strip_vertices = (*s)->vertices();
 	    v[0] = strip_vertices.begin();
 	    v[1] = v[0]; ++(v[1]);
 	    v[2] = v[1]; ++(v[2]);
 
-		// first vertex
-		svRep[0] = *(v[0]);
-		vertices->co[0] = svRep[0]->point2d()[0];
-		vertices->co[1] = svRep[0]->point2d()[1];
-		vertices->co[2] = 0.0;
-		++vertices;
+		vertex_index = 0;
+		visible = false;
 		
-		// second vertex
-		svRep[1] = *(v[1]);
-		vertices->co[0] = svRep[1]->point2d()[0];
-		vertices->co[1] = svRep[1]->point2d()[1];
-		vertices->co[2] = 0.0;
-		++vertices;
-		
-		// iterating over subsequent vertices: each vertex adds a new face
-		face_index = 0;
-		
-	    while( v[2] != strip_vertices.end() ) 
+	    for (n = 2; n < strip_vertex_count; n++)
 		{
-			// INPUT
 			svRep[0] = *(v[0]);
 			svRep[1] = *(v[1]);
 			svRep[2] = *(v[2]);
-			
-			color[0] = svRep[0]->color();
-			color[1] = svRep[1]->color();
-			color[2] = svRep[2]->color();
-			
-			// vertex
-			vertices->co[0] = svRep[2]->point2d()[0];
-			vertices->co[1] = svRep[2]->point2d()[1];
-			vertices->co[2] = 0.0;
-			
-			// faces
-			faces->v1 = face_index;
-			faces->v2 = face_index + 1;
-			faces->v3 = face_index + 2;
-			faces->v4 = 0;
-			
-			// colors
-			// red and blue are swapped - cf DNA_meshdata_types.h : MCol	
-			colors->r = (short)(255.0f*(color[0])[2]);
-			colors->g = (short)(255.0f*(color[0])[1]);
-			colors->b = (short)(255.0f*(color[0])[0]);
-			colors->a = (short)(255.0f*svRep[0]->alpha());
-			++colors;
-			
-			colors->r = (short)(255.0f*(color[1])[2]);
-			colors->g = (short)(255.0f*(color[1])[1]);
-			colors->b = (short)(255.0f*(color[1])[0]);
-			colors->a = (short)(255.0f*svRep[1]->alpha());
-			++colors;
-			
-			colors->r = (short)(255.0f*(color[2])[2]);
-			colors->g = (short)(255.0f*(color[2])[1]);
-			colors->b = (short)(255.0f*(color[2])[0]);
-			colors->a = (short)(255.0f*svRep[2]->alpha());
-			++colors;
-			
-			// ITERATION
+			m = 0;
+			for (int j = 0; j < 3; j++) {
+				p = svRep[j]->point2d();
+				if (p[0] < 0.0 || p[0] > width || p[1] < 0.0 || p[1] > height)
+					m++;
+			}
+			if (m == 3) {
+				visible = false;
+			} else {
+				if (!visible) {
+					vertex_index += 2;
+
+					// first vertex
+					vertices->co[0] = svRep[0]->point2d()[0];
+					vertices->co[1] = svRep[0]->point2d()[1];
+					vertices->co[2] = 0.0;
+					++vertices;
+					
+					// second vertex
+					vertices->co[0] = svRep[1]->point2d()[0];
+					vertices->co[1] = svRep[1]->point2d()[1];
+					vertices->co[2] = 0.0;
+					++vertices;
+				}
+				visible = true;
+
+				// vertex
+				vertices->co[0] = svRep[2]->point2d()[0];
+				vertices->co[1] = svRep[2]->point2d()[1];
+				vertices->co[2] = 0.0;
+				
+				// faces
+				faces->v1 = vertex_index - 2;
+				faces->v2 = vertex_index - 1;
+				faces->v3 = vertex_index;
+				faces->v4 = 0;
+				
+				// colors
+				// red and blue are swapped - cf DNA_meshdata_types.h : MCol	
+				color[0] = svRep[0]->color();
+				color[1] = svRep[1]->color();
+				color[2] = svRep[2]->color();
+
+				colors->r = (short)(255.0f*(color[0])[2]);
+				colors->g = (short)(255.0f*(color[0])[1]);
+				colors->b = (short)(255.0f*(color[0])[0]);
+				colors->a = (short)(255.0f*svRep[0]->alpha());
+				++colors;
+				
+				colors->r = (short)(255.0f*(color[1])[2]);
+				colors->g = (short)(255.0f*(color[1])[1]);
+				colors->b = (short)(255.0f*(color[1])[0]);
+				colors->a = (short)(255.0f*svRep[1]->alpha());
+				++colors;
+				
+				colors->r = (short)(255.0f*(color[2])[2]);
+				colors->g = (short)(255.0f*(color[2])[1]);
+				colors->b = (short)(255.0f*(color[2])[0]);
+				colors->a = (short)(255.0f*svRep[2]->alpha());
+				++colors;
+
+				++faces; ++vertices; ++colors;
+				++vertex_index;
+			}
 			++v[0]; ++v[1]; ++v[2];
-			++faces; ++vertices; ++colors;
-			++face_index;
-		
+
 		} // loop over strip vertices 
 	
 	} // loop over strips