Add support for GL_ARB_shading_language_include. Usage is identical to the way GL_GOOGLE_include_directive currently works glslang (since GL_ARB_shading_language_include is inherently a runtime feature and glslang is an offline compiler).
Users can simulate their runtime environment by using a custom glslang::TShader::Includer or using filenames that match their GL runtime names.
Add support for GL_ARB_shading_language_include. Usage is identical to the way GL_GOOGLE_include_directive currently works glslang (since GL_ARB_shading_language_include is inherently a runtime feature and glslang is an offline compiler).
Users can simulate their runtime environment by using a custom glslang::TShader::Includer or using filenames that match their GL runtime names.
Closes #249.