Abstract: When performing tile-based rendering a first, pre-pass operation in which primitives in a sequence of primitives for a tile are processed to determine visibility information for the sequence of primitives, the visibility information being usable to determine whether or not fragments for a primitive in the sequence of primitives should subsequently be processed further for the render output, is performed. Thereafter a second, main pass operation is performed in which the further processing of fragments for primitives that were processed during the first, pre-pass operation is controlled based on the determined visibility information for the sequence of primitives, such that for fragments for which the visibility information indicates that the fragments should not be processed further for the render output some or all of the processing during the second, main pass is omitted. Passes from different tiles can be interleaved.

Abstract: When performing tile-based rendering a first, pre-pass operation in which primitives in a sequence of primitives for a tile are processed to determine visibility information for the sequence, the visibility information being usable to determine whether fragments for a primitive in the sequence should subsequently be processed further, is performed. Thereafter a second, main pass operation is performed in which the further processing of fragments for primitives that were processed during the first, pre-pass operation is controlled based on the determined visibility information for the sequence of primitives, such that for fragments for which the visibility information indicates that the fragments should not be processed further for the render output some or all of the processing during the second, main pass is omitted. The visibility information indicates which primitives should be rendered for which sampling positions of the render output in a hierarchical manner.

Abstract: When performing tile-based rendering a first, pre-pass operation in which primitives for a tile are processed to determine visibility information, the visibility information being usable to determine whether fragments for a primitive in the sequence of primitives should subsequently be processed further for the render output, is performed. Thereafter a second, main pass operation is performed in which the further processing of fragments for primitives that were processed during the first, pre-pass operation is controlled based on the determined visibility information for the sequence of primitives, such that for fragments for which the visibility information indicates that the fragments should not be processed further for the render output some or all of the processing during the second, main pass is omitted. The visibility information indicates which primitives should be rendered for which sampling positions of the render output in a hierarchical manner.

Abstract: When performing tile-based rendering a first, pre-pass operation in which primitives for a tile are processed to determine visibility information, the visibility information usable to determine whether or not fragments for a primitive should subsequently be processed further for the render output, is performed. Thereafter a second, main pass operation is performed in which the further processing of fragments for primitives that were processed during the first, pre-pass operation is controlled based on the determined visibility information for the sequence of primitives, such that for fragments for which the visibility information indicates that the fragments should not be processed further for the render output some or all of the processing during the second, main pass is omitted. The visibility information indicates which primitives should be rendered for which sampling positions of the render output in a hierarchical manner.

Abstract: When performing tile-based rendering a first, pre-pass operation in which primitives in a sequence of primitives for a tile are processed to determine visibility information for the sequence of primitives, the visibility information being usable to determine whether or not fragments for a primitive in the sequence of primitives should subsequently be processed further for the render output, is performed. Thereafter a second, main pass operation is performed in which the further processing of fragments for primitives that were processed during the first, pre-pass operation is controlled based on the determined visibility information for the sequence of primitives, such that for fragments for which the visibility information indicates that the fragments should not be processed further for the render output some or all of the processing during the second, main pass is omitted. A data structure is also built to allow entire primitives to be culled.

Abstract: In a tile-based graphics processor when rendering a tile of a render output, which sub-regions, of a plurality of sub-regions that the tile has been divided into for fragment tracking purposes, fragments generated by the rasterisation stage fall within is determined. Then, for at least one sub-region of the plurality of sub-regions that the tile has been divided into, the processing of fragments for the sub-region of the tile is tracked to determine when the processing of all fragments for the sub-region of the tile has been finished. The writing of rendered fragment data for the sub-region of the tile from the tile buffer to memory is controlled on the basis of the tracking of the processing of fragments for the sub-region of the tile.

Abstract: When performing tile-based rendering in a graphics processing system, lists indicative of fragments to be processed are maintained for respective sub-regions of tiles to be rendered, with each list entry including, inter alia, at least an indication of the coverage within the tile sub-region of the group of fragments that the list entry represents, and an indication of whether the group of fragments that the list entry represents is eligible to undergo particular processing operations. The coverage information and eligibility information for the list entries is then used to control the processing of fragments for sub-regions of a tile, in such a way as to ensure that processing order dependencies are enforced and met.

Abstract: When performing tile-based rendering in a graphics processing system, lists indicative of fragments to be processed are maintained for respective sub-regions of tiles to be rendered, with each list entry representing a group of one or more fragments and including an indication of the coverage within the tile sub-region of the group of fragments that the list entry represents. The coverage information for the list entries is then used to set for entries in the list indicative of fragments to be processed for a sub-region, information indicating whether one or more processing operations are eligible to be performed for fragments that entries in the list represent.

Abstract: In a tile-based graphics processor when rendering a tile of a render output, which sub-regions, of a plurality of sub-regions that the tile has been divided into for fragment tracking purposes, fragments generated by the rasterisation stage fall within is determined. Then, for at least one sub-region of the plurality of sub-regions that the tile has been divided into, the processing of fragments for the sub-region of the tile is tracked to determine when the processing of all fragments for the sub-region of the tile has been finished. The writing of rendered fragment data for the sub-region of the tile from the tile buffer to memory is controlled on the basis of the tracking of the processing of fragments for the sub-region of the tile.

Abstract: A primitive that triggers performance of a graphics operation for the entirety of a tile is included in the sequence of primitives for a sequence of rendering tiles being provided to subsequent stages of the graphics processing pipeline for processing at least one tile in advance of the tile to which the primitive that is to trigger a graphics processing operation for the entirety of the tile relates. If, subsequent to the starting of the processing of the primitive that performs a processing operation for the entirety of the tile, it is determined that no other primitives will be processed for the tile, at least one of the subsequent processing stages of the graphics processing pipeline is caused to stop performing processing in respect of the primitive that performs a processing operation for the entirety of the tile.

Abstract: A method of operating a tile-based graphics processor that can use one of plural different rendering tile sizes is disclosed. The tile-based graphics processor includes a rasteriser that can rasterise primitives in a hierarchical manner. A patch size at which to begin the hierarchical testing of primitives in the rasteriser is selected based on the rendering tile size that is to be used. This can reduce the overall number of tests performed to rasterise primitives without impacting the correct functioning of the hierarchical rasterisation process.

Abstract: A method of operating a tile-based graphics processor that can use one of plural different rendering tile sizes is disclosed. The tile-based graphics processor includes a rasteriser that can rasterise primitives in a hierarchical manner. A patch size at which to begin the hierarchical testing of primitives in the rasteriser is selected based on the rendering tile size that is to be used. This can reduce the overall number of tests performed to rasterise primitives without impacting the correct functioning of the hierarchical rasterisation process.

Abstract: A method of operating a graphics processor that executes a graphics processing pipeline that can generate a render output using different shading rates is disclosed. First and second input shading rates are combined prior to rasterisation, and a combined shading rate may be propagated through the pipeline instead of the first and second input shading rates. The combined shading rate may then be combined with a third input shading rate at or after the rasterisation stage. This can reduce bandwidth, hardware and energy requirements.

Abstract: Disclosed herein is a bounding box that can be generated for a set of one or more primitive(s) and then passed to a rasteriser circuit for use thereby when generating the graphics fragments to be processed. The bounding box generation integrates a scissor test and allows primitives for which an initial bounding box has zero intersection with a specified scissor box to be discarded, whereas for primitives whose initial bounding box does intersect the scissor box, a new bounding box can be generated for output based on the area of intersection.

Abstract: Disclosed herein is a bounding box that can be generated for a set of one or more primitive(s) and then passed to a rasteriser circuit for use thereby when generating the graphics fragments to be processed. The bounding box generation integrates a scissor test and allows primitives for which an initial bounding box has zero intersection with a specified scissor box to be discarded, whereas for primitives whose initial bounding box does intersect the scissor box, a new bounding box can be generated for output based on the area of intersection.