diff --git a/data/test_scene.json b/data/test_scene.json
index 386ae31..339f59d 100644
--- a/data/test_scene.json
+++ b/data/test_scene.json
@@ -43,6 +43,26 @@
 				"y" : 10,
 				"z" : 10
 			}
+		},
+		{
+			"name" : "catepillar 2",
+			"model_file" : "catepillar.dae",
+			"position" : {
+				"x" : 600,
+				"y" : 400,
+				"z" : 0
+			},
+			"rotation" : {
+				"x" : 0,
+				"y" : 0,
+				"z" : 0,
+				"w" : 0
+			},
+			"scale" : {
+				"x" : 10,
+				"y" : 10,
+				"z" : 10
+			}
 		}
 	],
 
diff --git a/src/camera.cpp b/src/camera.cpp
index 791d3dc..c21411b 100644
--- a/src/camera.cpp
+++ b/src/camera.cpp
@@ -14,6 +14,7 @@ cameraInitPerspective(camera& cam, glm::vec3 position, glm::vec3 target, glm::ve
 	cam.vAngle = glm::atan((cam.target.z - cam.position.z) / (cam.target.y - cam.position.y));
 
 	// FIXME: bug, camera always starts with forward pointing at positive 'z' axis
+	// 	camera position also changes with change to window size
 	cam.forward = glm::normalize(glm::vec3(
 			glm::cos(cam.vAngle) * glm::sin(cam.hAngle),
 			glm::cos(cam.vAngle) * glm::cos(cam.hAngle),
diff --git a/src/camera.h b/src/camera.h
index ddfa375..d018e8b 100644
--- a/src/camera.h
+++ b/src/camera.h
@@ -8,6 +8,7 @@
 // TODO: store scene matrices on camera struct instead of global in renderer.h
 
 
+// TODO: add these props to scene json
 #define FOV 60.f
 #define ASPECT_RATIO 16.f/9.f
 #define NEAR_CLIP_PLANE 0.1f
diff --git a/src/render_group.cpp b/src/render_group.cpp
index 304071f..b6e071a 100644
--- a/src/render_group.cpp
+++ b/src/render_group.cpp
@@ -23,7 +23,8 @@ bool convertMeshInfo(meMeshInfo* mesh, render_object* ro, bool use_normals);
 void sendIndexBufferToGL(gl_index_buffer* index_buffer, GLenum usage, GLenum target);
 void drawRenderObject(render_group* rg, render_object* ro,
 		glm::mat4 model_matrix, glm::mat4 view_matrix, glm::mat4 projection_matrix,
-		glm::vec3 light_position, GLuint light_id, bool update_vertex_data);
+		glm::vec3 light_position, GLuint light_id,
+		bool update_vertex_data, bool update_color_data);
 
 
 // interface
@@ -147,11 +148,12 @@ rgBufferData(gl_buffer* buffer, GLenum usage, GLenum target)
 
 void
 rgDraw(render_group* rg, glm::mat4 model_matrix, glm::mat4 view_matrix, glm::mat4 projection_matrix,
-		glm::vec3 light_position, GLuint light_id, bool update_vertex_data)
+		glm::vec3 light_position, GLuint light_id,
+		bool update_vertex_data, bool update_color_data)
 {
 	for (uint i = 0; i < rg->num_objects; i++) {
 		drawRenderObject(rg, rg->render_objects[i], model_matrix, view_matrix, projection_matrix,
-				light_position, light_id, update_vertex_data);
+				light_position, light_id, update_vertex_data, update_color_data);
 	}
 }
 
@@ -282,7 +284,8 @@ convertMeshInfo(meMeshInfo* mesh, render_object* ro, bool use_normals)
 void
 drawRenderObject(render_group* rg, render_object* ro,
 		glm::mat4 model_matrix, glm::mat4 view_matrix, glm::mat4 projection_matrix,
-		glm::vec3 light_position, GLuint light_id, bool update_vertex_data)
+		glm::vec3 light_position, GLuint light_id,
+		bool update_vertex_data, bool update_color_data)
 {
 	glUseProgram(rg->shader.program_id);
 	glUniformMatrix4fv(rg->shader.model_matrix_id, 1, GL_FALSE, &model_matrix[0][0]);
@@ -307,9 +310,10 @@ drawRenderObject(render_group* rg, render_object* ro,
 		glBindBuffer(GL_ARRAY_BUFFER, ro->color_buffer.buffer_id);
 		glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 0, (void*) 0);
 
-		// TODO: maybe add an option to not send color data every frame?
-		glBufferSubData(GL_ARRAY_BUFFER, 0, ro->color_buffer.buffer_len * sizeof(GLfloat),
-				ro->color_buffer.buffer);
+		if (update_color_data) {
+			glBufferSubData(GL_ARRAY_BUFFER, 0, ro->color_buffer.buffer_len * sizeof(GLfloat),
+					ro->color_buffer.buffer);
+		}
 	}
 
 	// 3rd attribute buffer: normals
diff --git a/src/render_group.h b/src/render_group.h
index 0342b28..e58de1e 100644
--- a/src/render_group.h
+++ b/src/render_group.h
@@ -70,7 +70,8 @@ rgBufferData(gl_buffer* buffer, GLenum usage, GLenum target);
 
 void rgDraw(render_group* rg, glm::mat4 model_matrix,
 		glm::mat4 view_matrix, glm::mat4 projection_matrix,
-		glm::vec3 light_position, GLuint light_id, bool update_vertex_data = false);
+		glm::vec3 light_position, GLuint light_id,
+		bool update_vertex_data = false, bool update_color_data = false);
 
 void rgFree(render_group* rg);
 
diff --git a/src/renderer.cpp b/src/renderer.cpp
index 181d28d..5aaf0c4 100644
--- a/src/renderer.cpp
+++ b/src/renderer.cpp
@@ -118,10 +118,13 @@ initRenderer(SDL_Handles &handles, v2i vpDims)
 
 	glEnable(GL_DEPTH_TEST);
 	glEnable(GL_LINE_SMOOTH);
+	glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
+#if 0
+	// TODO: blending messes up rendering with mesa on intel graphics 4000
 	glEnable(GL_BLEND);
 	glBlendEquation(GL_FUNC_ADD);
 	glBlendFunc(GL_ONE, GL_SRC_ALPHA);
-	glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
+#endif
 
 	// TODO: glDebugMessageCallback is only availabe  from >v4.3
 	//  check and warn if context doesn't support this function here
@@ -356,7 +359,7 @@ renderFrame(std::vector<hex_info> *hexes, Entity* entities, uint32 entity_count)
 	gl_buffer& color_buf = rg->render_objects[0]->color_buffer;
 	fillColorBuffer(color_buf.buffer, color_buf.buffer_len, hexes);
 	rgDraw(rg, m_model, m_view, m_projection,
-		g_test_light.position, g_test_light.light_ID);
+		g_test_light.position, g_test_light.light_ID, false, true);
 
 	// hex lines
 	rgDraw(g_hex_line_render_group, m_model, m_view, m_projection,