[Savannah-hackers] submission of Waves, Clouds, and Sand - savannah.nongnu.org

[planet10]

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M.C. Lewis <address@hidden> described the package as follows:
License: gpl
Other License: 
Package: Waves, Clouds, and Sand
System name: oceanscene
Type: non-GNU

Description:
OpenGL-based research project for simulating natural phenomenae.  First plan is 
ocean waves, then clouds, then terrain (sand).  Intend to use latest features 
of 3D cards such as texture/fragment shaders, register combiners, and vertex 
programs.  Development on GNU/Linux.

There are a few \"free\" issues here.  One is that the two video card 
manufacturers which have extensive OpenGL functionality (ATI and NVidia) have 
proprietary drivers, which load into the x86 Linux kernel, sometimes FreeBSD, 
Windows (of course), and that\'s about it.  Unfortunately, no useful Free 
drivers exist for this hardware.  Hopefully, by making advanced graphics 
software that runs primarily on GNU/Linux and other free platforms, 3D on Linux 
will stay current, so that we won\'t just be starting on 3D years down the road 
when Free drivers become available.

Second, I may wish to make use of some software with free-looking, but 
nonstandard, licensing.  E.g., GLVU:
http://www.cs.unc.edu/~walk/software/glvu/
// GLVU : Copyright 1997 - 2002
//        The University of North Carolina at Chapel Hill
//------------------------------------------------------------------------------
// Permission to use, copy, modify, distribute and sell this software and its
// documentation for any purpose is hereby granted without fee, provided that
// the above copyright notice appear in all copies and that both that copyright
// notice and this permission notice appear in supporting documentation.
// Binaries may be compiled with this software without any royalties or
// restrictions.
//
// The University of North Carolina at Chapel Hill makes no representations
// about the suitability of this software for any purpose. It is provided
// \"as is\" without express or implied warranty.

Also, OpenEXR:
http://www.openexr.net/

Which uses the modified BSD license:
http://www.ilm.com/opensource/ilm-bsd-lic.html

Since I will be using the GNU GPL for my software, I am not sure if I can 
\"swallow\" some of the software, meaning release it under the GNU GPL if 
compatible; or if I can only link against it.

Part of the issue is that there are numerous re-implementations of common items 
like 3D vectors, matrices, etc.  They all essentially say the same thing; dot 
products are simply math!  GLVU uses a vector basis camera; its LookAt() 
function is virtually identical to the GLU (GL Utility library)\'s version 
(http://mesa3d.org), except in C++.  I am quite confused as to copyright issues 
on classes that simply implement straight math, where any implementation is 
virtually indistinguishable from another, except for formatting!
Most of these classes need to be compiled into the program, not just linked, 
because of inlined function speed.  

Third, I have downloaded an extensive set of research papers describing 
graphics techniques, some of which are hard to find; I am not sure how much of 
these I can excerpt for tutorials on a technique.

Fourth, Intel has a very fast \"approximate math library\", which seems to be 
under a rather onerous license.  They know how to write a faster sqrt(), seeing 
as they made the chips.  Probably any independent implementation of some of 
these functions using SSE2 would result in identical ASM code.
http://www.intel.com/design/Pentium4/devtools/

As an example of the usefulness of fast math in 3D, POVray doubled in speed 
just from a better sqrt() on the Alpha:
http://www.uwsg.iu.edu/hypermail/linux/alpha/9601.1/0046.html

I\'m currently working through research papers; no code yet, but I will likely 
be using a good deal of GLfx++, a GNU GPLed project at:

http://www.mpi-sb.mpg.de/~bg/software/GLfxpp.shtml


Other Software Required:
URLs given above; possibilities include:
GLVU
GLfx++
OpenEXR


Other Comments:
This is planned to be A (one of many) client for my other project, MOFO, hosted 
here at Savannah.