public override void Draw(TextureArray2D texture)
{
// draw checkerss
base.Draw(texture);
GL.Enable(EnableCap.Blend);
GL.BlendFunc(BlendingFactorSrc.SrcAlpha, BlendingFactorDest.OneMinusSrcAlpha);
shader.Bind();
shader.SetTransform(GetTransform());
shader.SetFarplane(CalcFarplane());
shader.SetLevel((float)models.Display.ActiveMipmap);
shader.SetGrayscale(models.Display.Grayscale);
models.GlData.BindSampler(shader.GetTextureLocation(), true, models.Display.LinearInterpolation);
texture.BindAsCubemap(shader.GetTextureLocation());
// draw via vertex array
models.GlData.Vao.DrawQuad();
GL.Disable(EnableCap.Blend);
Program.Unbind();
}