Inside Macintosh: Apple Game Sprockets Guide /

Chapter 2 - DrawSprocket / DrawSprocket Reference

DrawSprocket Functions / Manipulating Color Lookup Tables

DSpContext_SetCLUTEntries

You can use the DSpContext_SetCLUTEntries function to assign one or more color entries to a color lookup table.

OSStatus DSpContext_SetCLUTEntries (
		DSpContextReference inContext,
		const ColorSpec *inEntries,
		UInt16 inStartingEntry,
		UInt16 inEntryCount);

inContext

The context whose color lookup table is to be modified.

inEntries

A pointer to an array of color specification records.

inStartingEntry

The (zero-based) index position in the color lookup table of the first entry to replace.

inEntryCount

The number of entries to replace.

function result

A result code.

DESCRIPTION

The DSpContext_SetCLUTEntries function allows you to change a range of entries in a color lookup table, for purposes such as color-table animation. You pass in the context whose color lookup table is to be modified in the inContext parameter, the index position of the first entry to replace in the inStartingEntry parameter, and the number of entries to replace in the inEntryCount parameter. The inEntries parameter contains a pointer to the array of new entries.

Because of video hardware limitations, the changes you make to a color table with this function may not take effect until the next vertical retrace. Nevertheless, this function attempts to execute asynchronously and return immediately, so your program can continue execution without having to wait for the changes to be made.

CALLING RESTRICTIONS

Do not call this function during an interrupt.