Inside Macintosh: QuickDraw GX Objects /

Chapter 2 - Shape Objects / Shape Objects Reference

Functions / Directly Manipulating a Shape's Geometry

GXChangedShape

You can use the GXChangedShape function to notify QuickDraw GX that you have directly edited the geometry of a shape.

void GXChangedShape(gxShape target);

target

A reference to the shape object whose geometry you have directly edited.

DESCRIPTION

The GXChangedShape function notifies QuickDraw GX that the geometry of the shape referenced by the target parameter has been modified. QuickDraw GX can then use that information to invalidate existing shape caches, if necessary.

You need to call this function only if you have directly edited a shape's geometry by using the pointer returned by the GXGetShapeStructure function. If you edit a shape geometry using any other shape-editing function, you do not need to call GXChangedShape.

To directly edit a shape's geometry, call GXLockShape followed by GXGetShapeStructure. After editing, call GXUnlockShape followed by GXChangedShape.

ERRORS, WARNINGS, AND NOTICES

Errors
shape_is_nil

SEE ALSO

The GXLockShape, GXUnlockShape, and GXGetShapeStructure functions are described in the previous sections.

Shape caches are discussed in the section "Caching Shape Objects" beginning on page 2-27.

Other functions for editing shape geometries are described in the shape-specific chapters of Inside Macintosh: QuickDraw GX Graphics and Inside Macintosh: QuickDraw GX Typography.