About Style Objects

A style object (or, more briefly, a style ) is a type of QuickDraw 3D object that determines some of the basic characteristics of the renderer used to draw the geometric objects in a scene. A style is of type TQ3StyleObject , which is a subclass of a shape object.

You can apply a style to a model by creating a style object and then submitting it to the model. QuickDraw 3D provides functions that allow both retained and immediate style submitting. Alternatively, you can create a style object and then add it to a group. Then, when the group is submitted for rendering, the style is applied to all objects in the group (if it's an ordered display group) or to all objects in the group following the style (if it's a display group).

See the chapter "Group Objects" for complete information on how styles are applied to the objects in a group.

QuickDraw 3D defines these types of styles that affect the rendering or picking of a scene:

• backfacing styles
• interpolation styles
• fill styles
• highlight styles
• subdivision styles
• orientation styles
• shadow-receiving styles
• picking ID styles
• picking parts styles

Unlike attributes, which define characteristics of the appearances of individual surfaces and can be applied to only part of a model, styles define characteristics of a renderer and are generally (but not always) applied to a model as a whole.

Some renderers might not support all types of styles, and some renderers might not be able to apply a given style to all geometric objects. For example, not all renderers can draw shadows; such renderers therefore ignore the shadow-receiving style.

If you apply a style to an object and then apply a different style of the same type to that object, the style applied second replaces the style applied first.

Backfacing Styles

Interpolation Styles

Fill Styles

Highlight Styles

Subdivision Styles

Orientation Styles

Shadow-Receiving Styles

Picking ID Styles

Picking Parts Styles

Anti-Alias Style

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© 1997 Apple Computer, Inc.

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