Persistent buffer mapping is an OpenGL technique where the contents of a
buffer object are mapped to a persistent pointer instead of having to
map and unmap a buffer every time it is modified.
This decreases the overhead for updating data in a uniform buffer object
which now only consists of a memcpy and a flush call.
This is in preparation for using persistently mapped buffers for uniform
buffers. Since that functionality is not available in the OpenGL version
we are targetting I implemented a fall-back which simply uses
glBufferSubData.
I did a benchmark with these changes and there was no change in
performance to the current master version.
This allows to render screen space decals into the deferred lighting
buffers no matter how complex the underlying geometry is.
Currently there is only limited support for using this in the engine.
Only weapon impact decals are supported at the moment for testing
purposes.
This uses UBOs for building a buffer object of uniform data before
using that data to draw objects. This should reduce the CPU overhead by
reducing the amount of glUniform calls required for executing a single
draw call. This is especially useful if rendering is limited by the CPU
which should help performance for people with slower CPUs.
This fixes#910.
This converts the deferred lighting shader to use uniform buffers for
the dynamic data sent to the GPU while rendering the lighting effects.
This doesn't affect performance but the deferred lighting code is a
nicely isolated piece of rendering code where I could test how the
rendering code could use the uniform buffers.
This is related to #910.
asarium