Hi Vincent, "V. de Weger" <[EMAIL PROTECTED]> wrote on 02/05/2007 09:39:19 AM:
> Just my luck: I have to rotate! > > I've got the save part working, but how do I zoom/pan/rotate after loading > the saved viewport? There are a large number of approaches to solve this problem. My suggestion would be to map three of your points through the 'current' ScreenCTM. This will give you three points in screen space s0,s1,s2. Now what you want to do is calculate the Affine Matrix that will map those three points (say top-left, bottom-left, top-right) to the windows corners w0, w1, w2. Now an affine matrix has six values, and with three points you have six equations (x & y for each). Now it's just a matter of doing a little algebra. s0.x*sx + s0.y*shy + tx = w0.x s0.x*shy + s0.y*sy + ty = w0.y [...] When you calculate that transform then just preConcatenate it with the current Rendering Transform and set the result as the new rendering transform. --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
