摘要:
Circuitry for drawing lines includes a video memory for storing pixel data and circuitry for generating a sequence of addresses defining a line of pixels in the video memory. A first memory stores a sequence of pattern units corresponding to the generated sequence of addresses. A second memory stores a value indicating a current pattern unit. Writing circuitry writes to the video memory at a generated address responsive to a current pattern unit. A third memory stores a control value which is accessed by update circuitry for updating the second memory to indicate the next pattern unit. The update circuitry may selectively update the second memory to the sequential pattern unit or reset the second memory to a predetermined pattern unit.
摘要:
Line draw circuitry receives parameters defining first and second endpoints of a line and calculates line parameters based on the first and second endpoints. The line parameters are then stored in a memory. A "calculate-only" control signals determines whether a line is drawn immediately after calculation (and storing) of the end parameters or whether the line is drawn responsive to a subsequent "start" signal. If the line is to be drawn responsive to the start signal, the line parameters may be modified prior to drawing the line.
摘要:
A graphics processor uses a line draw facility to receive first and second values indicative of the coordinates of respective first and second end points of a line. The reception of the second value is sensed by the line draw facility and line data is generated responsive to the sensing of the second value.