Abstract: A method, apparatus, and computer instructions for managing color maps in a data processing system. Responsive to a request to add a color map to a color table, a determination is made as to whether the color map is already installed in the color table. If the color map is not already installed in the color table, a decision is made as to whether a free block of color table entries sufficient to hold the color map is present in the color table. A determination is made as to whether existing blocks of color table entries in the color table can be rearranged to form a new free block of color table entries, if the free block of color table entries is insufficient to hold the color map. The existing blocks of color table entries in the color table are rearranged if the existing blocks of color table entries can be rearranged to form the new free block of color table entries.

Abstract: A method, data processing system, and computer instructions for simulating direct frame buffer access. A request for access to a frame buffer memory is received from an application. A portion of system memory is allocated for use as the frame buffer memory in response to receiving the request. A pointer to the portion of system memory is returned to the application. The application writes data to the portion of system memory, treating the portion of system memory like the frame buffer memory.

Abstract: The present invention provides a mechanism by which the number of bits used to identify the WIDs for each of the color buffer and the overlay buffer may be programmed into the graphics adapter based on the currently active application environment. With the apparatus and method of the present invention, a programmable WAT color size selection device is provided in a RAMDAC of the graphics adapter. This programmable WAT color size selection device may be dynamically programmed to use varying bit splits of a WID from a WID buffer to obtain different indexes into a color WAT table and an overlay WAT table. In this way, different splits of, for example, an eight bit WID may be obtained based on the setting of the programmable WAT color size selection device such that varying color and overlay capabilities are obtainable dynamically.

Abstract: A method, apparatus and computer instructions for processing graphics data in a graphics adapter for a set of clip areas in a clip region. Trivial rejection is performed on primitives to reject any primitive outside of the set of clip rectangles, wherein a set of identified primitives is formed in which the set of identified primitives contain unrejected primitives. The set of identified primitives is sent to a memory in the graphics adapter as a command stream to form a set of stored commands. A hardware clipper in the graphics adapter is set to an unprocessed clip rectangle within the set of clip rectangles. The set of identified primitives for the unprocessed clip rectangle is processed using the hardware clipper with the set of stored commands in the memory. The setting of the hardware clipper and the rendering of the set of identified primitives is repeated for each unprocessed clip rectangle until all of the clip rectangles in the set of clip rectangles are processed.

Abstract: A system and method for tracking memory leaks is presented. A user sets a memory tracking flag that notifies the system to track memory allocations and memory de-allocations. A memory array is initialized which includes multiple memory array slots. Each memory array slot includes a free flag and fields to store information corresponding to a memory allocation. When memory is allocated to an application or file, the system locates an unused memory array slot, sets the free flag to false, and stores memory allocation information in the memory array slot. When the application or file de-allocates the memory, the system locates the corresponding allocated memory array slot and sets the corresponding free flag to true, indicating a proper memory de-allocation. Upon shutdown, the system reviews the status of each free flag corresponding to each memory array slot, and generates a report which includes memory allocations that are not properly de-allocated.

Abstract: Smoother transitions between changing cursor images which are less stressful to the interactive user of a computer controlled display are provided by apparatus for changing the cursor image, including a frame buffer for storing the display screen image as a pixel array, a separate display buffer for storing the current cursor image as a pixel array, together with apparatus for storing an alternate cursor image as a pixel array during the display of the current cursor image, and means for replacing the current cursor image with the alternate cursor image. In raster scan apparatus for maintaining screen images in the frame buffer on said display screen, there are means for effecting the replacement of said cursor images during a vertical blanking period in said raster scanning.

Abstract: In a basic display screen interface implementation for enabling an interactive user to move a data component from a source to a destination in said system via means for representing said data component by an item, e.g. icon on said display screen combined with means for interactively dragging said item from an initial location on said screen representative of said source to a final location representative of said destination, there is provided a further expedient for interactively modifying the data component before said dragged item reaches said final location. The implement for dragging said icon includes an implement for dragging the icon into contact with another icon to thereby activate the means for interactively modifying the data component represented by said dragged icon.

Abstract: A method, apparatus, and computer instructions for managing a plurality of color tables in a display device. A request is received for a requested colormap of a particular type. In response to the colormap being absent, a determination is made as to whether an empty color table is present. In response to an empty color table being absent, a determination is made as to whether a color table containing a current colormap of the particular type is present. The current colormap is replaced with the requested colormap in response to a current color table of the particular type being present.

Abstract: A method, apparatus, and computer instructions for displaying data. Each entry in a plurality of entries for an overlay window attribute table (WAT) is set with identical information in which a window identifier is unnecessary for accessing the information in the overlay WAT. Information in a color WAT is retrieved using the set of window identifiers in response to receiving a set of window identifiers. The information in the overlay WAT is retrieved without requiring the window identifier. Pixels are displayed on a display screen using the information retrieved from the color WAT and the information retrieved from the overlay WAT.

Abstract: A system and method for tracking memory leaks is presented. A user sets a memory tracking flag that notifies the system to track memory allocations and memory de-allocations. A memory array is initialized which includes multiple memory array slots. Each memory array slot includes a free flag and fields to store information corresponding to a memory allocation. When memory is allocated to an application or file, the system locates an unused memory array slot, sets the free flag to false, and stores memory allocation information in the memory array slot. When the application or file de-allocates the memory, the system locates the corresponding allocated memory array slot and sets the corresponding free flag to true, indicating a proper memory de-allocation. Upon shutdown, the system reviews the status of each free flag corresponding to each memory array slot, and generates a report which includes memory allocations that are not properly de-allocated.