Inside Macintosh: QuickTime /

Chapter 2 - Movie Toolbox / Movie Toolbox Reference

Matrix Functions /

ScaleMatrix

The ScaleMatrix function allows your application to modify the contents of a matrix so that it defines a scaling operation.

pascal void ScaleMatrix (MatrixRecord *m, Fixed scaleX, 
                        Fixed scaleY, Fixed aboutX, Fixed aboutY);

m

Contains a pointer to a matrix structure. The ScaleMatrix function updates the contents of this matrix so that the matrix describes a scaling operation--that is, it concatenates the respective transformations onto whatever was initially in the matrix structure. You specify the magnitude of the scaling operation with the scaleX and scaleY parameters. You specify the anchor point with the aboutX and aboutY parameters.

scaleX

Specifies the scaling factor applied to x coordinates.

scaleY

Specifies the scaling factor applied to y coordinates.

aboutX

Specifies the x coordinate of the anchor point.

aboutY

Specifies the y coordinate of the anchor point.

ERROR CODES

None