1. A graphics processor, comprising: a renderer for rendering graphics fragments for display and that comprises one or more rendering units that can be configured to different rendering states; a memory for storing a plurality of sets of data, each set of data defining a different rendering state for configuring the rendering units of the renderer; a processor for associating a graphics fragment to be rendered with one of the stored rendering state data sets by including in data that represents the graphics fragment information that indicates the one stored rendering state data set to be used for the graphics fragment; and a processor for issuing graphics fragments that have been associated with a stored rendering state data set to the rendering units of the renderer for rendering; wherein: one or more of the rendering units of the renderer comprise: a processor for determining the rendering state data set associated with a graphics fragment to be rendered; and a processor for configuring the rendering unit in accordance with the determined rendering state data set, wherein the processor for determining the rendering state associated with a graphics fragment to be rendered is arranged to be responsive to one of the rendering units receiving a first graphics fragment to be rendered, to determine the rendering state associated with the first graphics fragment by using the information that indicates the stored rendering state data set to be used for the first graphics fragment included in the data that represents the first graphics fragment, to be responsive to the rendering unit receiving a next graphics fragment to be rendered, and to determine the rendering state associated with the next graphics fragment by using the information that indicates the stored rendering state data set to be used for the next graphics fragment included in the data that represents the next graphics fragment, and wherein the rendering state associated with the first graphics fragment is different from the rendering state associated with the next graphics fragment.