CpuGLVB: reading data back from the GPU each time model is changed is not very efficient.
Model the GL VB after D3D11 one, where there are no data read backs, however this means
an extra memory copy of the buffer. 4th level uniform subdiv on Car, glGetBufferSubData
was taking 50% of CPU time before (actual subdiv 22%), now that is gone. Full CPU Draw
62ms -> 54ms, looks like most of overhead now is just waiting on GL queries).
glViewer: line widths larger than 1.0 are deprecated in core GL (generates a GL error)
glViewer: don't generate GL errors with invalid UBO indices (happens on OSX since tessellation is not supported)
glViewer: set sync off on all platforms
CpuGLVB: dirty flag to not keep on uploading if data did not change
Update README.md
osd_regression: add "CL" backend that tests OpenCL kernel with GL buffer backing
CpuGLVB: code review changes
build fixes :
- remove ptexViewer from the build on OSX (doesnt work)
- remove maya plugins from the build on OSX (until we have a compatible version available)

glViewer fixes :
- fix incorrect GLFW version check in #ifdefs (now done in cmake)
- fix default program GL version (downgraded to 1.5 where necessary)
- remove non core-profile GL calls (triggering errors)

this should allow OSX 10.7 builds to produce a functional, if restricted, glViewer.

fixes #111
Revamped Python bindings that use SWIG
partial solution to run-time environment configuration :
- add bool OsdGLDrawContext::SupportsAdaptiveTessellation() method
- modify glViewer to use that instead of #ifdefs

Note : this is not the final word on this as OSD really needs a more comprehensive
system to provide run-time information about available features to the client code.

fixes #111
removing more #ifdef's related to adaptive tessellation ability

fixes #111
add some logic to enable full-screen mode with GLFW 3.0

confirmed working on Windows - needs checking on other
platforms / versions of GLFW

fixes #113
Fixed WIN32 build breakage.

GLFW tries to avoid including windows.h, but by hijacking
macro definitions provided by windows.h GLFW actually
further pollutes the global namespace.
fixes a problem on Linux where apparently there is no "primary" monitor returned (NULL)

fixes #113
Fix ptex guttering on corner pixels.

Fixes #114
Merge branch 'master' of https://github.com/PixarAnimationStudios/OpenSubdiv
Merge pull request #110 from aras-p/osd_regression_work

osd_regression: add "CL" backend that tests OpenCL kernel
iterating on the cmake stuff for a python module
- fixed GL context crashes for Linux / GLFW 3.0
- refactored CLI arguments parsing
- minor code style cleanups