public void FindOrAdd2()
        {
            using (GraphicsWindow window = Device.CreateWindow(1, 1))
            {
                ShaderCache cache = new ShaderCache();

                ShaderProgram sp = cache.FindOrAdd("PassThrough",
                    ShaderSources.PassThroughVertexShader(),
                    ShaderSources.PassThroughFragmentShader());
                ShaderProgram sp2 = cache.FindOrAdd("PassThrough2",
                    ShaderSources.PassThroughVertexShader(),
                    ShaderSources.PassThroughFragmentShader());

                Assert.AreNotEqual(sp, sp2);

                cache.Release("PassThrough");
                cache.Release("PassThrough2");
            }
        }