From: Joe Van Dyk <joevandyk@...>
Date: 2005-03-01T03:55:07+09:00
Subject: Re: Rendering ruby openGL output to a file.

On Tue, 1 Mar 2005 01:02:43 +0900, Eric Peden <eric@ericpeden.com> wrote:
> On Feb 28, 2005, at 5:26 AM, Brian Schr�der wrote:
> > ow I want to include the images into
> > my thesis, and I'd like to use a higher resolution that what my screen
> > can give. Is it possible to render the image not onto the screen, but
> > into a file, using a bigger-than-screen resolution? I'm quite an
> > opengl newbie so maybe this is obious?
> 
> You might get some use out of RMagick, a Ruby interface for
> ImageMagick/GraphicsMagick:
> 
>    http://rmagick.rubyforge.org/
> 
> The OpenGL API works with raw color values packed into an array;
> RMagick (as far as I can tell) cannot. You should be able to draw your
> scene offscreen, then do a readPixels() and then convert the resulting
> array to RMagick Pixel values. Tell RMagick what your intended
> resolution is, and it will handle the rest.
> 

I did something like this, except with C and ImageMagick.  It was
actually easier for me (for some reason) to process the arrays in C
rather than in Ruby back then.