A rasterizer stage configured to implement multiple interpolators for graphics pipeline. The rasterizer stage includes a plurality of simultaneously operable low precision interpolators for computing a first set of pixel parameters for pixels of a geometric primitive and a plurality of simultaneously operable high precision interpolators for computing a second set of pixel parameters for pixels of the geometric primitive. The rasterizer stage also includes an output mechanism coupled to the interpolators for routing computed pixel parameters into a memory array. Parameters may be programmably assigned to the interpolators and the results thereof may be programmably assigned to portions of a pixel packet.

Method and system for implementing multiple high precision and low precision interpolators for a graphics pipeline

A method and system for rendering bicubic surfaces whereby at least a portion of the bicubic surfaces are defined by sixteen control points and bounded by four boundary curves, and each boundary curve is formed by boundary box of line segments formed between four of the control points. The method and system of include transforming only the control points of the surface given a view of the object, rather than points across the entire bicubic surface. Next, a pair of orthogonal boundary curves to process is selected. After the boundary curves have been selected, each of the curves is iteratively subdivided, wherein two new curves are generated with each subdivision. The subdivision of each of the curves is terminated when the curves satisfy a flatness threshold expressed in screen coordinates, whereby the number of computations required to render the object is minimized.

Bicubic surface rendering

Methods and computer-storage media are provided for rendering three-dimensional (3D) graphics by tessellating objects using novel structures and algorithms. Rendering utilizing “patches,” configurable functions that include a specified number of control points, allows for computation on a per-patch or per-control-point basis, in addition to traditional per-vertex, per-primitive, and per-pixel methods. This produces a number of advantages over previous tessellation methods, including the reuse of computations across existing vertices and the ability to process at a lower frequency. The operations to compute points are simplified in order to optimize system resources used in the process. Transitions from un-tessellated to tessellated objects are smoother utilizing the present invention, while developers have more flexibility in the level of detail present at different edges of the same patch. Detail within a displacement map also can be increased without negative effects associated with previous systems and methods.

Efficient geometric tessellation and displacement

A method and system is provided for rendering bicubic surfaces of an object on a computer system. Each bicubic surface is defined by sixteen control points and bounded by four boundary curves, each corresponding to an edge, and each boundary curve is formed by boundary box of line segments formed between four of the control points. The method and system of include transforming only the control points of the surface given a view of the object, rather than points across the entire bicubic surface, and using the four boundary edges for purposes of subdivision. Next, a pair of orthogonal boundary curves to process is selected. After the boundary curves have been selected, each of the curves is iteratively subdivided and the pair of orthogonal internal curves, wherein two new curves are generated with each subdivision. The subdivision of each of the curves is terminated when the curves satisfy a flatness threshold expressed in screen coordinates, whereby the number of computations required to render the object is minimized.

Rapid zippering for real time tesselation of bicubic surfaces

A drawing processing apparatus for performing tessellation processing, comprising a pixel shader and a texture unit. An internal division operation part of the pixel shader issues texture load instructions to the texture unit, specifying parametric coordinate values of a patch of a parametric surface, and thereby acquires internal division factors interpolated based on the parametric coordinate values from the texture unit. The internal division operation part issues texture load instructions to the texture unit further, specifying the internal division factors acquired from the texture unit as new interpolation factors, and thereby acquires control points internally divided based on the internal division factors in advance from the texture unit. Based on the internal division factors corresponding to the parametric coordinate values, the internal division operation part performs recursive internal division operations on the control points acquired from the texture unit, thereby determining a point on the parametric surface corresponding to the parametric coordinate values.

Drawing processing apparatus, texture processing apparatus, and tessellation method

The present invention provides a graphics processing unit for rendering objects from a software application executing on a processing unit in which the objects to be rendered are received as control points of bicubic surfaces. According to the method and system disclosed herein, the graphics processing unit includes a transform unit, a lighting unit, a renderer unit, and a tessellate unit for tessellating both rational and non-rational object surfaces in real-time.

Adrian Sfarti

Papers

Bicubic surface real time tesselation unit