Abstract: A system and method for modifying the configuration of one or more graphics adapters and one or more displays without rebooting the system allows a user to quickly transition between different graphics adapter/display configurations. A single display driver interfaces between the operating system and the one or more graphics devices. The display driver reconfigures the one or more graphics devices to change the adapter/display configuration without shutting down or rebooting the system. Unlike a conventional system reboot performed by the operating system, the display driver checks that there are no memory leaks or error conditions during the reconfiguration.

Abstract: A system and method for modifying the configuration of one or more graphics adapters and one or more displays without rebooting the system allows a user to quickly transition between different graphics adapter/display configurations. A single display driver interfaces between the operating system and the one or more graphics devices. The display driver reconfigures the one or more graphics devices to change the adapter/display configuration without shutting down or rebooting the system. Unlike a conventional system reboot performed by the operating system, the display driver checks that there are no memory leaks or error conditions during the reconfiguration.

Abstract: Systems and methods for providing on-demand memory management. In response to a mapping request from a device driver or other program, a first portion of the memory is mapped to one or more virtual addresses in a first region of a virtual memory space so that it can be directly accessed by the CPU. In response to an unmapping request the first portion of the memory is unmapped. Mapping and unmapping requests may be made at any time.

Abstract: An apparatus for processing high level instructions including a plurality of processing units, means for generating a plurality of instructions to perform said high level instructions, and means for dynamically organizing said generated instructions into at least one group, each group including at least one instruction to be processed by one of said processing units. In addition, a method of processing high level instructions by a plurality of processing units including generating a plurality of instructions to perform said high level instructions, and dynamically organizing said generated instructions into at least one group, each group including at least one instruction to be processed by one of said processing units.

Abstract: A system and method is provided for displaying trimmed surfaces on a computer graphics system. The present invention tessellates a three-dimensional surface into triangles and determines whether a trimming curve intersects any triangles. If an intersection occurs, a polygon trimming mask is formed by performing an exclusive OR operation and rendering the polygon into a mask plane. The XOR operation sets the bits in the mask plane corresponding to the trimming mask to logical 1. The rendering hardware then compares the bits in the mask plane with the bits in the frame buffer and draws those pixels which correspond to the bits set to 1 in the mask plane. Since, the trimming mask is a polygon the rendering hardware can perform shading, or lighting calculations using values for points which are contained on the tessellated triangle. In this manner, consistent lighting of a trimmed surface can be achieved.

Abstract: A method for producing realistic shading of three-dimensional objects depicted in a graphics display system. Computationally efficient Gouraud shading is practiced in the rendering of images which routinely require Phong shading to obtain suitable realism. Gouraud shading is adaptively applied to polygon regions of preferably triangular shape at a granularity defined by heuristically derived relationships using surface normal vectors, incident light vectors and relative pixel separation information. When division of the base triangle is dictated, the methodology produces a mesh of polygons sized to be individually rendered with Gouraud shading yet provide Phong-like realism for the whole of the original polygon region.

Abstract: This invention enables voice energy to be distinguished from energy due to other sources such as telephone call progress signals. A portion of the audio spectrum is divided into a high and into a low frequency band and the energy content of these bands is examined. The audio energy of a signal is passed through a set of filters and compared. A frequency boundary crossing of an input signal subsequent to filtering is used to signify the receipt of a voice signal. By operating in this manner, voice, whose predominant frequency switches in a random fashion from being greater than to less than a cutoff frequency, can be distinguished from other signals either below or above the cutoff frequencies of the filters. The detection of voice energy is not begun until a predetermined threshold of energy has been received for a specified period of time. This specified period of time need not be continuous after a ringback signal is received.