Re: Drawing views into NSImage

FROM : Ricky Sharp
DATE : Mon Apr 04 13:11:50 2005

On Monday, April 04, 2005, at 01:28AM, Geert B. Clemmensen <<email_removed>> wrote:

>I have N views (or more specifically, N subviews of a content view that
>holds M subviews with M >= N). I want to draw these N views into an
>NSImage. I calculate the proper rect and initializes an NSImage
>instance accordingly, i.e. its size matches that of the calculated
>rect. I then do:
>
>    [myImage lockFocus];
>        // fill the image with clearColor
>        // draw the N views via drawRect: calls
>    [myImage unlockFocus];
>
>This kinda works, i.e. I get an NSImage that almost looks right, but I
>haven't been able to consistently have the N views draw so their
>relative position to each other is kept. I have tried enough variants
>of NSAffineTransform with -concat/-set (with and without
>save/restoreGraphicsState) to realize that this may not be the way to
>go. What is the recommended/preferred way to change the coordinate
>system before each call to drawRect:?


Check out the following sample:

<http://developer.apple.com/samplecode/Color_Sampler/Color_Sampler.html>

Specifically, look at NSView_snapshot.m which is a category on NSView that will generate an image of it.  Simply lock focus on your top-level view and send it a snapshot message.

--
Rick Sharp
Instant Interactive(tm)