This is the kind of information that should be in the manuals.

Thanks, Luc-Eric.

Matt



-----Original Message-----
From: [email protected] 
[mailto:[email protected]] On Behalf Of Luc-Eric Rousseau
Sent: Tuesday, December 03, 2013 8:45 AM
To: [email protected]
Subject: Re: Open GL High Quality ?

OK, since no one discussed it, here is the explanation as to why the High 
Quality Viewport does not implement depth cut/fog.

The fog parameter in the display setting is an OpenGL 1.x feature, "glFog".  
Like all old OpenGL features, "fixed pipeline" stuff, it is not implemented 
with fragment shaders.  When you use fragment shaders, the shader must 
implement *everything*, lighting/shading/texturing.
If it were to be fog, than it's up to that shader to implement that.
When you switch to any real time shader viewport in Softimage, fog ceases to 
work, because it's no longer the opengl fixed pipeline driving this stuff, it's 
your render tree.

Now, what is the HQV?  It's not an OpenGL 1.x emulator, it's your
render tree compiled as realtime shader format with MetaSL.   When you
draw a render region there is no fog. The "phong" in Softimage/Mental Ray does 
not have a fog parameter.

So what you need to do is to make a render tree that implements that fog 
shading.

On Mon, Dec 2, 2013 at 4:54 AM, olivier jeannel <[email protected]> wrote:
> Joke aside,
> I'm consulted for WebGL aplication. I just wanted to rough-up a scene 
> (which has to include fog and normal maps) in XSI to kind of make a 
> fast preview and set some lighting /ambient.
> It's completly useless here...

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