// createContext creates an OpenGL context, binds it as the current context
// stored in thread-local storage, and locks the current goroutine to an os
// thread.
func createContext() *contextGL {
// The OpenGL active context is stored in TLS.
runtime.LockOSThread()
c := new(contextGL)
C.CGCreate(&c.ctx)
// Using attribute arrays in OpenGL 3.3 requires the use of a VBA.
// But VBAs don't exist in ES 2. So we bind a default one.
var id C.GLuint
C.glGenVertexArrays(1, &id)
C.glBindVertexArray(id)
return c
}
// createContext creates an OpenGL context, binds it as the current context
// stored in thread-local storage, and locks the current goroutine to an os
// thread.
func createContext() (*contextGL, error) {
// The OpenGL active context is stored in TLS.
runtime.LockOSThread()
c := new(contextGL)
if cglErr := C.CGCreate(&c.ctx); cglErr != C.kCGLNoError {
return nil, fmt.Errorf("CGL: %v", C.GoString(C.CGLErrorString(cglErr)))
}
// Using attribute arrays in OpenGL 3.3 requires the use of a VBA.
// But VBAs don't exist in ES 2. So we bind a default one.
var id C.GLuint
C.glGenVertexArrays(1, &id)
C.glBindVertexArray(id)
return c, nil
}