Function

CGRectInset

Returns a rectangle that is smaller or larger than the source rectangle, with the same center point.

Declaration

CGRect CGRectInset(CGRect rect, CGFloat dx, CGFloat dy);

Parameters

rect

The source CGRect structure.

dx

The x-coordinate value to use for adjusting the source rectangle. To create an inset rectangle, specify a positive value. To create a larger, encompassing rectangle, specify a negative value.

dy

The y-coordinate value to use for adjusting the source rectangle. To create an inset rectangle, specify a positive value. To create a larger, encompassing rectangle, specify a negative value.

Return Value

A rectangle. The origin value is offset in the x-axis by the distance specified by the dx parameter and in the y-axis by the distance specified by the dy parameter, and its size adjusted by (2*dx,2*dy), relative to the source rectangle. If dx and dy are positive values, then the rectangle’s size is decreased. If dx and dy are negative values, the rectangle’s size is increased.

Discussion

The rectangle is standardized and then the inset parameters are applied. If the resulting rectangle would have a negative height or width, a null rectangle is returned.

See Also

Modifying Rectangles

CGRectDivide

Divides a source rectangle into two component rectangles.

CGRectIntegral

Returns the smallest rectangle that results from converting the source rectangle values to integers.

CGRectIntersection

Returns the intersection of two rectangles.

CGRectOffset

Returns a rectangle with an origin that is offset from that of the source rectangle.

CGRectStandardize

Returns a rectangle with a positive width and height.

CGRectUnion

Returns the smallest rectangle that contains the two source rectangles.