I am creating an outline glow (aura) effect for a mobile game (android) and have noticed that the cost of a graphics.blit is quite high. Even only doing a “blit(source,dest)” and nothing else is slow (-5~-7fps).
I wanted to know if there are any methods / techniques that can reduce the decrease in frames ?
Any alternatives to using graphics.blit ? (Render to a full screen quad ?, Render MainCamera To RT, then do post work, then composite and blit to screen ?)
I can manage to get around 40 FPS, but its not an acceptable frame rate.
If there really is no way to do Post Render work on mobile, I will go a different route.
About my setup:
Testing on a Samsung Galaxy S5 with Android 5.
I have a post effect script attached to the main camera.
Main Camera does NOT render to an RT. It just renders normally.
I am doing my post effect work in “OnRenderImage”.
I am using 2 or 3 temporary render textures at runtime (RenderTexture.GetTemporary)
I have a color RenderTexture and a depth RenderTexture. The size is a quarter of the source RT.
I have some CommandBuffers set up to render the models that I want to create the outline glow effect for.
The models all get rendered to my temp RT, then the RT is blurred, then composited with the source RT.