3 files changed, 51 insertions, 9 deletions

diff --git a/source/blender/gpu/GPU_extensions.h b/source/blender/gpu/GPU_extensions.h
index b2378f0dae6..bb0cf2dd2b9 100644
--- a/source/blender/gpu/GPU_extensions.h
+++ b/source/blender/gpu/GPU_extensions.h
@@ -148,6 +148,7 @@ void GPU_framebuffer_texture_detach(GPUTexture *tex);
 void GPU_framebuffer_slot_bind(GPUFrameBuffer *fb, int slot);
 void GPU_framebuffer_texture_unbind(GPUFrameBuffer *fb, GPUTexture *tex);
 void GPU_framebuffer_free(GPUFrameBuffer *fb);
+bool GPU_framebuffer_check_valid(GPUFrameBuffer *fb, char err_out[256]);
 
 void GPU_framebuffer_restore(void);
 void GPU_framebuffer_blur(GPUFrameBuffer *fb, GPUTexture *tex, GPUFrameBuffer *blurfb, GPUTexture *blurtex);
diff --git a/source/blender/gpu/intern/gpu_extensions.c b/source/blender/gpu/intern/gpu_extensions.c
index 37a787be20e..faec3cc3481 100644
--- a/source/blender/gpu/intern/gpu_extensions.c
+++ b/source/blender/gpu/intern/gpu_extensions.c
@@ -866,12 +866,17 @@ GPUFrameBuffer *GPU_framebuffer_create(void)
 		return NULL;
 	}
 
+	/* make sure no read buffer is enabled, so completeness check will not fail. We set those at binding time */
+	glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fb->object);
+	glReadBuffer(GL_NONE);
+	glDrawBuffer(GL_NONE);
+	glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
+	
 	return fb;
 }
 
 int GPU_framebuffer_texture_attach(GPUFrameBuffer *fb, GPUTexture *tex, int slot, char err_out[256])
 {
-	GLenum status;
 	GLenum attachment;
 	GLenum error;
 
@@ -906,14 +911,6 @@ int GPU_framebuffer_texture_attach(GPUFrameBuffer *fb, GPUTexture *tex, int slot
 		return 0;
 	}
 
-	status = glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT);
-
-	if (status != GL_FRAMEBUFFER_COMPLETE_EXT) {
-		GPU_framebuffer_restore();
-		GPU_print_framebuffer_error(status, err_out);
-		return 0;
-	}
-
 	if (tex->depth)
 		fb->depthtex = tex;
 	else
@@ -1026,6 +1023,29 @@ void GPU_framebuffer_texture_unbind(GPUFrameBuffer *UNUSED(fb), GPUTexture *UNUS
 	glPopAttrib();
 }
 
+
+bool GPU_framebuffer_check_valid(GPUFrameBuffer *fb, char err_out[256])
+{
+	GLenum status;
+	
+	glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fb->object);
+	GG.currentfb = fb->object;
+	
+	/* Clean glError buffer. */
+	while (glGetError() != GL_NO_ERROR) {}
+	
+	status = glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT);
+	
+	if (status != GL_FRAMEBUFFER_COMPLETE_EXT) {
+		GPU_framebuffer_restore();
+		GPU_print_framebuffer_error(status, err_out);
+		return false;
+	}
+	
+	return true;
+}
+
+
 void GPU_framebuffer_free(GPUFrameBuffer *fb)
 {
 	int i;
@@ -1162,6 +1182,12 @@ GPUOffScreen *GPU_offscreen_create(int width, int height, char err_out[256])
 		GPU_offscreen_free(ofs);
 		return NULL;
 	}
+	
+	/* check validity at the very end! */
+	if (!GPU_framebuffer_check_valid(ofs->fb, err_out)) {
+		GPU_offscreen_free(ofs);
+		return NULL;		
+	}
 
 	GPU_framebuffer_restore();
 
diff --git a/source/blender/gpu/intern/gpu_material.c b/source/blender/gpu/intern/gpu_material.c
index d6244b4255b..e4228bedf9d 100644
--- a/source/blender/gpu/intern/gpu_material.c
+++ b/source/blender/gpu/intern/gpu_material.c
@@ -1868,6 +1868,11 @@ GPULamp *GPU_lamp_from_blender(Scene *scene, Object *ob, Object *par)
 				return lamp;
 			}
 
+			if (!GPU_framebuffer_check_valid(lamp->fb, NULL)) {
+				gpu_lamp_shadow_free(lamp);
+				return lamp;				
+			}
+			
 			/* FBO and texture for blurring */
 			lamp->blurfb = GPU_framebuffer_create();
 			if (!lamp->blurfb) {
@@ -1885,6 +1890,11 @@ GPULamp *GPU_lamp_from_blender(Scene *scene, Object *ob, Object *par)
 				gpu_lamp_shadow_free(lamp);
 				return lamp;
 			}
+			
+			if (!GPU_framebuffer_check_valid(lamp->blurfb, NULL)) {
+				gpu_lamp_shadow_free(lamp);
+				return lamp;				
+			}			
 		}
 		else {
 			lamp->tex = GPU_texture_create_depth(lamp->size, lamp->size, NULL);
@@ -1897,6 +1907,11 @@ GPULamp *GPU_lamp_from_blender(Scene *scene, Object *ob, Object *par)
 				gpu_lamp_shadow_free(lamp);
 				return lamp;
 			}
+			
+			if (!GPU_framebuffer_check_valid(lamp->fb, NULL)) {
+				gpu_lamp_shadow_free(lamp);
+				return lamp;				
+			}						
 		}
 
 		GPU_framebuffer_restore();