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Subject: Re: Redrawing graphics objects
Date: Wed, 15 Oct 2008 06:26:01 +0000 (UTC)
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Walter Roberson <roberson@hushmail.com> wrote in message <SdeJk.734$1r2.316@newsfe01.iad>...
> Which renderer are you using? If you are using the OpenGL renderer (only), then
> the stacking order of lines compared to flat objects at the same Z plane ignored.
> -Somewhere- it is documented which will show up on top, but I have found that
> in practice it depends upon your graphics drivers and upon your operating system --
> e.g., for me on Linux-64 over X, the order is the reverse of what is documented.
> 
> If you are using any renderer other than OpenGL, then the stacking order is
> supposedly obeyed... but OpenGL is the only renderer that supports transparency...
> In theory if you add a small Z offset to either the line or the image
> (or patch) then they will no longer be in the same plane and the one that
> is "closer" to the viewpoint will appear "on top". 

Hi Walter,

Thank you for the ideas.  I'm on Win Vista, and I tried all 3 renderers.  Zbuffer and OpenGL behave like you described for OpenGL.  It seems like the stacking of the objects is random when using these Renders because there is a lot of flashing as the image updates. 

Adding a zdata offset when using the painters renderer works well.

It would be nice to figure out a way to control the stacking order when using OpenGL, but I'm very happy this is working with Painters.

Thanks!