About QuickDraw GX Graphics
With QuickDraw GX, you create graphics by creating QuickDraw GX shapes. Graphics shapes include geometric shapes, bitmap shapes, and picture shapes:
All QuickDraw GX shapes share the same basic structure. They are all represented by a shape object and its associated style, ink, and transform objects. Figure 1-1 shows the four basic QuickDraw GX objects and lists the properties of each. This figure includes all of the properties of these objects. However, this book examines only a subset of these properties. Properties not examined in this book are grayed out.
- Geometric shapes are the building blocks for graphics. These shapes, which include points, lines, curves, rectangles, polygons, and paths, make up the graphic elements supported by most drawing programs. There are also two special types of geometric shapes: empty shapes, which cover no area, and full shapes, which cover all area.
- Bitmap shapes contain pixel images. These shapes allow you to create graphics by specifying the color value of each pixel in the image.
- Picture shapes are collections of QuickDraw GX shapes, including other picture shapes.
Figure 1-1 Shape object structure
Like all shapes, geometric shapes are represented by a shape object in memory. Three of the properties of the shape object--shape type, shape geometry, and shape
fill--and how they apply to geometric shapes in particular, are introduced in the
section "Geometric Shapes" beginning on page 1-7 and are fully discussed in the chapter "Geometric Shapes" in this book.Geometric shapes use the style object properties highlighted in Figure 1-1. These properties are introduced in the section "Geometric Styles, Inks, and Transforms" beginning on page 1-11 and are fully examined in the chapter "Geometric Styles" in this book.
Geometric shapes also use the properties of their ink and transform objects. You can find more information about these objects in the chapters "Ink Objects" and "Transform Objects" in Inside Macintosh: QuickDraw GX Objects.
Bitmap shapes use their shape, style, ink, and transform objects, although they make limited use of some of the properties of these objects. Bitmap shapes are introduced in the section "Bitmap Shapes" beginning on page 1-17 and are fully examined in the chapter "Bitmap Shapes" in this book.
Picture shapes use their shape and transform objects, but do not use their style or ink objects. Picture shapes are introduced in the section "Picture Shapes" beginning on page 1-20 and are fully examined in the chapter "Picture Shapes" in this book.
QuickDraw GX allows you to convert between the different types of shapes. Table 1-1 describes where to look in each book for information regarding each possible kind of conversion.
Main | Page One | What's New | Apple Computer, Inc. | Find It | Contact Us | Help
