MakeRGBPat

MakeRGBPat Provides best possible RGB match on current device

#include <Quickdraw.h> Color Quickdraw

void MakeRGBPat( thePpat, myColor );

PixPatHandle thePpat ; the pixel pattern to create in memory

RGBColor *myColor ; closest match to the requested RGB color

components

MakeRGBPat generates a pixPat that approximates the requested color.

thePpat is the handle of the pixel pattern to create in memory.

myColor is the closest match to the requested RGB currently available.

Notes: MakeRGBPat generates the closest possible color match to the requested

RGB, given the current equipment. On a device with 4 bits per pixel,

MakeRGBPat will yield 125 possible colors -- as opposed to 16 colors

on the same device if you'd just set the foreground color and commenced

drawing.

MakeRGBPat makes more colors theoretically possible by alternating

between four colors in a pattern. While this gives you an increased range

of colors, the alternating color selection doesn't allow for a very solid

pattern and should be avoided when using elements that are one pixel wide.

Each 8-by-8 pattern component is composed of computed colors. Colors

are arranged in an RGB pattern as follows (with pattern map boundary

always containing (0,0,8,8) and the rowbytes equal to 2:

Value RGB

0 computed RGB color

1 computed RGB color

2 computed RGB color

3 computed RGB color

4 RGB color sent to MakeRGBPat

For each color table it creates, MakeRGBPat only fills in the last

colorSpec field. All the other values for colorSpec are computed on the

current device's pixel depth when the figure is drawn.

Referenced by (6):