Instance Method

drawAtPoint:fromRect:operation:fraction:

Draws all or part of the image at the specified point in the current coordinate system.

Declaration

- (void)drawAtPoint:(NSPoint)point fromRect:(NSRect)fromRect operation:(NSCompositingOperation)op fraction:(CGFloat)delta;

Parameters

point

The location in the current coordinate system at which to draw the image.

srcRect

The source rectangle specifying the portion of the image you want to draw. The coordinates of this rectangle are specified in the image's own coordinate system. If you pass in NSZeroRect, the entire image is drawn.

op

The compositing operation to use when drawing the image. See the NSCompositingOperation constants.

delta

The opacity of the image, specified as a value from 0.0 to 1.0. Specifying a value of 0.0 draws the image as fully transparent while a value of 1.0 draws the image as fully opaque. Values greater than 1.0 are interpreted as 1.0.

Discussion

The image content is drawn at its current resolution and is not scaled unless the CTM of the current coordinate system itself contains a scaling factor. The image is otherwise positioned and oriented using the current coordinate system.

Unlike the compositeToPoint:fromRect:operation: and compositeToPoint:fromRect:operation:fraction: methods, this method checks the rectangle you pass to the srcRect parameter and makes sure it does not lie outside the image bounds.

See Also

Drawing the Image

- drawInRect:

Draws the image in the specified rectangle.

- drawInRect:fromRect:operation:fraction:

Draws all or part of the image in the specified rectangle in the current coordinate system.

- drawInRect:fromRect:operation:fraction:respectFlipped:hints:

Draws all or part of the image in the specified rectangle respecting the hints and the orientation of the current coordinate system.

- drawRepresentation:inRect:

Draws the image using the specified image representation object.

NSCompositingOperation

Compositing operators, described in terms of having source and destination images, each having an opaque and transparent region.