Patent ID: 6337690
Filing Date: 2002-01-08
Classification: G09G

Abstract:
A method of organizing and utilizing an image buffer to reduce the frequency of buffer clear operations, comprising the steps of:a) storing a clear color value in a first clear color register in a frame buffer controller and in a second clear color register in a video controller; b) storing a count value in a first clear count register in the frame buffer controller and in a second clear count register in the video controller; c) for each pixel in the image buffer, writing the clear color value into a color bit field and writing the count value into a count bit field; d) drawing an image into the image buffer while writing the count value stored in the first clear count register into the count bit field of each pixel modified during the drawing step; and e) incrementing the count value stored in the first and second clear count registers; f) repeating steps d) and e) until the count value stored in the first and second clear count registers reaches a maximum value; and then g) repeating steps a), b) and c).