Inside Macintosh: QuickDraw GX Objects /

Chapter 4 - Colors and Color-Related Objects / About Color Set Objects

Color Set Properties

The interface to color set objects is entirely procedural. You manipulate the information in a color set by modifying its properties using QuickDraw GX functions.

Color set objects have four accessible properties, as shown in Figure 4-19. Note that, because a color set is an object and not a data structure, the order of the properties as shown in Figure 4-19 is completely arbitrary. Properties in italics are references to other objects.

Figure 4-19 The color set object and its properties

These are the four accessible properties in a color set:

• Color space. The color space of all the color values in the color set. A color set can have only a single color space, which cannot be gxIndexedSpace.
• Color-value array. An array of color values (not gxColor structures). Only the types of color values specified in the gxSetColor union are valid in a color set.
• Owner count. The number of existing references to this color set object.
• Tag list. A list of references to custom information about this color set object, stored in private data structures called tag objects. The chapter "Tag Objects" in this book describes tag objects in general and how you can use them to add custom information to objects.

QuickDraw GX provides functions to manipulate each of these properties. Note that there is no color profile property for a color set; profile information for the colors in a color set is found in the bitmap structure--or the color structure in the ink object--to which the color set is attached.