I agree; this seems like a scene attribute, so I'd put it on the camera - like the background color. I'd suggest that you look for an attribute attached to the camera.
GregI Randall Hopper <[EMAIL PROTECTED]>@opendx.watson.ibm.com on 02/12/2002 02:36:00 PM Please respond to [email protected] Sent by: [EMAIL PROTECTED] To: [email protected] cc: Subject: [opendx-dev] Fog (was Re: Translucent Texturing) Richard Gillilan: |Hi Randall. It's fantastic to see someone working on the OpenGl |parts. Every thought of enabling glFog? I've wanted this function for |years because linear black fog (depth cuing) is a pretty essential |feature for any molecular modeling program. I've looked at some of the |source code, and will make a serious attempt at it soon, but you may have |already thought about it. It would seem like a natural for enviro-viz |uses. The pure OpenGL bits should be pretty simple. The questions in my mind relate to how this would map to the data model (which objects are affected by it, are the fog bits object attributes or global Render settings, are screen objects exempt, ...) Conceptually it's a scene attribute, so it'd be a shame to have to set it identically on all the fields in a scene (can Options even do this?). Maybe something like Transform that affects a tree of objects, like fog attributes on a Group node? I think that's a departure from the current model however. Hopefully Greg will have some insight on this. In terms of what attributes, I "think" this covers OpenGL: fog = { on/off } fog_mode = { linear, exp, exp2 } fog_color = { r,g,b,a } fog_density = density fog_distance = { min, max } fog_hint = { dont_care, nicest, fastest } Which begs the question what would be good defaults in case none of these except fog on/off are specified. Randy -- Randall Hopper (mailto:[EMAIL PROTECTED]) Lockheed Martin Operation Support EPA Scientific Visualization Center US EPA N127-01; RTP, NC 27711
