A graphics processor includes a graphics object list building unit that determines the location of each draw call in a scene to be rendered and generates a list of draw calls for each sub-region (tile) that the scene to be rendered is divided into. The draw call lists are stored in a memory. A graphics object selection unit of a renderer of the graphics processor then determines which draw call is to be rendered next by considering the draw call list stored in the memory for the sub-region (tile) of the scene that is currently being rendered.