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Chapter 3 - Image Compression Manager / Image Compression Manager Reference

Application-Defined Functions

Alignment Functions

Your application can use alignment functions to specify the alignment in any of the Image Compression Manager's alignment functions (described in "Aligning Windows" beginning on page 3-136). You call the alignment function with a rectangle (defined in global screen coordinates) that has already been aligned using the default behavior. The alignment function then has the option of applying some additional alignment criteria to the rectangle, such as vertical alignment of some form. In the case of supporting hardware alignment, it is the function's responsibility to determine if the rectangle applies to the relevant device.

The AlignmentProcPtr data type defines a pointer to an alignment function. You assign an alignment function by passing a pointer to the alignment function structure, which identifies the alignment function to the appropriate function.

/* alignment function structure */
typedef struct 
{
   AlignmentProcPtr  alignmentProc;    /* pointer to your 
                                          alignment function */
   long              alignmentRefCon;  /* reference constant */
} AlignmentProcRecord, *AlignmentProcRecordPtr;

Field Description

alignmentProc

Points to your alignment function.

alignmentRefCon

Contains a reference constant for use by your alignment function.

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Subtopics

MyAlignmentProc