Function gfx_device_gl::create_main_targets_raw

pub fn create_main_targets_raw(
    dim: Dimensions, 
    color_format: SurfaceType, 
    depth_format: SurfaceType
) -> (RawRenderTargetView<Resources>, RawDepthStencilView<Resources>)

Create the proxy target views (RTV and DSV) for the attachments of the main framebuffer. These have GL names equal to 0. Not supposed to be used by the users directly.