Graphics display system with color look-up table loading mechanism

A color lookup table (CLUT) loading mechanism for an integrated circuit graphics display system, said mechanism comprising:

• a window controller for processing a data structure that can provide an indicator to load the CLUT, and for generating a CLUT memory request signal and a CLUT memory write signal to control CLUT loading, wherein the data structure can alternatively be used to define graphics contents of a window;
• a CLUT controller for resetting a write pointer for the CLUT responsive to the CLUT memory request signal;
• a memory clock;
• and
• a direct memory access (DMA) module for transferring conversion data from memory to the CLUT synchronously to the memory clock

A graphics display system on an integrated circuit, comprising:

• a window controller for processing a data structure that can provide an indicator to load the CLUT, and for generating a CLUT memory request signal and a CLUT memory write signal to control CLUT loading, wherein the data structure can alternatively be used to define graphics contents of a window;
• a CLUT controller for resetting a write pointer for the CLUT responsive to the CLUT memory request signal;
• a memory clock;
• a direct memory access (DMA) module for transferring conversion data from memory to the CLUT synchronously to the memory clock;
• a display engine for receiving CLUT-formatted graphics data, and converting the CLUT-formatted graphics data into first graphics data having a common format using the CLUT, for receiving other graphics data and converting the other graphics data into second graphics data having the common format, and for blending the first graphics data with the second graphics data to generate blended graphics.

A method of processing graphics data in a display engine that processes graphics images formatted in a plurality of formats including a color look up table (CLUT) format, the method comprising the steps of:

• generating a plurality of common data structures, said common data structures comprising at least one data structure that describes graphics contents of a window and at least one data structure that provides an indicator to load a CLUT, said common data structures being in a sequence;
• processing the common data structures to determine which ones of the common data structures describe graphics contents of a window and which ones of the common data structures provide an indicator to load the CLUT;
• and
• loading conversion data into the CLUT in response to the indicator to load the CLUT, the CLUT-formatted data capable of being applied to the conversion data as an address to access graphics data having different data format,
• wherein the data structures for providing an indicator to load the CLUT can appear anywhere in the sequence, and a whole scan line time is allowed for loading the CLUT in consideration that it generally takes longer to load the CLUT than time available in a horizontal blanking interval.

A CLUT loading mechanism for an integrated circuit graphics display system, said mechanism comprising:

• a window controller for sorting data, the data being formatted into data structures having a common structure and used to describe windows, according to the depth of the window on the display;
• a CLUT for receiving conversion data from memory;
• and
• a direct memory access module for transferring the conversion data from memory to the CLUT,
• wherein the data structures comprise at least one data structure that provides an indicator to load the CLUT, and wherein a whole scan line time is allowed for re-loading the CLUT in consideration that it generally takes longer to load the CLUT than time available in a horizontal blanking interval.