Several rendering changes have resulted in a non-rendering build that
failed to build from source. Dummy out all of these functions to make it
work again.
Cherry-picked.
Author: Nicolas Hake <isilkor@openclonk.org>
Date: Wed Jun 17 21:30:56 2015 +0200
Conflicts:
src/lib/StdMesh.h
The last row of the bone transformation matrix always is 0,0,0,1 so
there's no point in uploading it. Also reducing the max bone count to 80
which means the uniform array will fit into the available space on 6000
and 7000 series Geforce GPUs.
If we're short on uniform components, don't transpose the transformation
matrix before sending it to the shader, and transpose it in the shader
itself instead, saving 4 components per bone.
Instead of transforming all vertices on the CPU every time an animation
progresses, we now only recalculate the skeleton, leaving the heavy
lifting for the GPU. This also means we no longer have to push all
vertices onto the bus every frame, because the mesh isn't changing and
can therefore be stored in a GL_STATIC_DRAW VBO when it's first loaded.
The downside of this approach is that there's only a limited number of
uniforms and vertex attributes we can pass to the shader. At the moment
these limits are a maximum of 128 bones per skeleton, and no vertex can
be influenced by more than 8 bones at once. So far this is no problem,
as the most complex skeleton in the base game uses less than 64 bones
and no more than 6 bone weights per vertex.
The idea here is that we compose shaders out of "slices", which can
come from the engine ("built-in"), from files or possibly even from
models. This should allow us to more easily share the code between
different rendering shaders (e.g. for lights / normals).
TODO: Workarounds not yet implemented, so this might degrade less
gracefully.
Nicolas Hake