Re: Graphics transforms

On Mar 19, 11:45 am, "visionset" <s...@xxxxxxxxxxxx> wrote:
I'm drawing a Rectangle somewhere on a Graphics object over an image and
rotating it some degrees about its centre.
I now want to use that rectangle to describe the part of the image I want to
grab.
To grab it I'm stuffing it in a BufferedImage by drawing on its Graphics
like so:

// rect is a Shape
// origin is the min x & min y of the rectangle
Point centre = rect.getCentre();

g2.rotate(-rect.getTheta(), centre.x, centre.y);

Point orig = rect.getOrigin();

g2.translate(-orig.x, -orig.y);

g2.setClip(rect);

renderTiles(g2);

The rotation works fine. But I can't figure out the translation to get it
back to 0,0

Any clues folks?

TIA

--

Mike W

You reverse the translations you've done.
g2d.translate(orig.x, orig.y);
g2d.rotate(rect.getTheta(), centre.x, centre.y);

.

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