"The idea of this new OpenGL feature is :
- set RestartIndex = "n"
- draw elements strip
-> when the index is "n", the strip is "stopped" and restarted
It's very usefull for drawing tiles with a single strip and a "restart" at the end of each row.
The idea a an OSG StateAttribute is :
Usually we use to build geometry from code, because software modelers rarely support it (and 3d file formats doesn't support it) :
-RootNode <= "PrimitiveRestartIndex=0" // So now, we know that our restart index is 0 for all drawables under this node
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- Drawable 1 : triangles => as usual
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- Drawable 2 : triangles strip => as usual
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- Drawable 3 : triangles strip + "GL_PRIMITIVE_RESTART" mode = ON => use the restart index
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- Drawable 4 : triangles strip + "GL_PRIMITIVE_RESTART" mode = ON => use the restart index
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- Drawable 5 : triangles strip => as usual
With a StateAttribute, it's easy for the developper to say "0 will be my restart index for all this object" and then activate the mode only on some nodes.
The main problem is if you set and restart index value which is not included in the vertex array (for exemple set restart index = 100 but you have only 50 vertex). There is no problem with OpenGL, but some OSG algorithms will try to access the vertex[100] and will segfault.
To solve this, I think there is two ways :
1/ add restart index in osg::PrimitiveSet and use this value in all algorithms. It's a lot of work, maybe dangerous, and it concern only a few situations : developpers who use this extension should be aware of advanced OpenGL (and OSG) data management
2/ use a StateAttribute, and choose a "correct" restart index. In my applications, I always use "0" as a restart index and duplicate the first vertex (vertex[0] = vertex[1]). So there is no difference for OpenGL and all OSG algorithms works properly.
"
- add non square matrix
- add double
- add all uniform type available in OpenGL 4.2
- backward compatibility for Matrixd to set/get an float uniform matrix
- update of IVE / Wrapper ReadWriter
implementation of AtomicCounterBuffer based on BufferIndexBinding
add example that use AtomicCounterBuffer and show rendering order of fragments,
original idea from geeks3d.com."
A few things remain to do:
* The binding between a uniform block in a shader program and a buffer indexed target number is fixed, like a vertex attribute binding. This is too restrictive because that binding can be changed without relinking the program. This mapping should be done by name in the same way that uniform values are handled i.e., like a pseudo state attribute;
* There's no direct way yet to query for the offset of uniforms in uniform block, so only the std140 layout is really usable. A helper class that implemented the std140 rules would be quite helpful for setting up uniform blocks without having to link a program first;
* There's no direct support for querying parameters such as the maximum block length, minimum offset alignment, etc. Having that information available outside of the draw thread would make certain instancing techniques easier to implement."
handle scenes with multiple views with elements that need coordinating on a per view basis.
Added beginings of new osgText::FadeText class (not functionality yet).
"updates for GLSL core integration:
Code compiles and runs on win32.
Basic functionality of Program and Shader in place.
Program derived from StateAttribute.
Uniform value propagation is not yet functional (in development)
Includes some patches by Nathan Cournia.
includes example testcase to demo use of new classes."
