Mark Satterthwaite 83ad7e246f Implemented desktop OpenGL support for GL_ARB_separate_shader_objects without requiring any additional shader platforms to reduce shader compile/link hitches. ...

- Shaders which emit layout location data use INTERFACE_LOCATION & INTERFACE_BLOCK macros to defer to the runtime whether they can be used as separable or non-separable shaders.
- The runtime supplies the correct #define for each so that the shaders still work on platforms where the glLinkProgram implementation fails with separable shader code.
- Shader model 5 platforms (GLSL 430 or ES 3.10) which were already specifying & using layout location data continue to do so, even when using glLinkProgram.
- The 'OpenGL.UseSeparateShaderObjects' console variable allows switching between SSO/Link modes between executions, but not dynamically at runtime.
- Only defaults to on for Mac as that is the only platform which can guarantee that the extension is always available & so far the most tested platform.
- Updated hlslcc binaries are supplied for Mac, Linux & Windows.
- Added an OpenGL RHI stat for shader first draw time so that it is easy to see why hitches occur during runtime due to in-driver shader compilation.

reviewedby michael.trepka, nick.penwarden, dmitry.rekman, rolando.caloca

[CL 2435530 by Mark Satterthwaite in Main branch]

2015-02-06 11:35:30 -05:00

..

Private

Implemented desktop OpenGL support for GL_ARB_separate_shader_objects without requiring any additional shader platforms to reduce shader compile/link hitches.

2015-02-06 11:35:30 -05:00

ShaderFormatOpenGL.Build.cs

Update copyright notices to 2015.

2014-12-07 19:09:38 -05:00