QM_RotateMatrix

QM_RotateMatrix(matrixRec; numDegrees; anchorH; anchorV):error
	matrixRec	Array real	Matrix record
	numDegrees	Real	Number of degrees
	anchorH	Real	Horizontal coordinate of the anchor point
	anchorV	Real	Vertical coordinate of the anchor point
	error	Longint	Error result

Adds a rotation transformation to a matrix record.

Parameter matrixRec specifies the matrix. It must be declared as a 3 x 3 array of reals. QMedia updates and returns the contents matrixRec with the specified rotation operation.

Parameter numDegrees specifies the number of degrees of the rotation operation.

Parameters anchorH and anchorV specify the horizontal and vertical coordinates of the anchor point.

Example

`Rotate track ID $trackID of movie $movie by 30 degrees around its center

ARRAY REAL($matrix;3;3)
$err:=QM_SetIdentityMatrix ($matrix)

C_REAL($trachWidth;$trackHeight)
$err:=QM_GetTrackDimensions ($movie;$trackID;$trachWidth;$trackHeight)

C_REAL($degrees;$hAnchor;$vAnchor)
$degrees:=30 `Rotate 30 degrees
$hAnchor:=$trachWidth/2 `Anchor at center of track
$vAnchor:=$trackHeight/2
$err:=QM_RotateMatrix ($matrix;$degrees;$hAnchor;$vAnchor)

$err:=QM_SetTrackMatrix ($movie;$trackID;$matrix)

Related commands

QM_SetIdentityMatrix	Sets the contents of a matrix record to the identity matrix.
QM_TranslateMatrix	Adds a translation transformation to a matrix record.
QM_ScaleMatrix	Adds a scaling transformation to a matrix record.
QM_SkewMatrix	Adds a skew transformation to a matrix record.
QM_ConcatMatrix	Concatenates two matrices.
QM_SetTrackMatrix	Changes the track's transormation matrix.
QM_GetTrackMatrix	Returns the track's transormation matrix.