4 // require_extensions: GL_ARB_shader_subroutine
8 #extension GL_ARB_shader_subroutine: require
10 /* The ARB_shader_subroutine spec says nothing to
11 * explicitly disallow calling subroutine implementations
12 * as normal functions.
14 * It seems reasonable that this would still work.
17 subroutine void func_type();
19 /* A subroutine matching the above type */
20 subroutine (func_type) void impl() {}
22 /* Call the function directly, rather than via
23 * a subroutine uniform.