new (window:Window)
context:RenderContext
onContextLost:Event<Void ‑> Void> = new Event<Void>()
onContextRestored:Event<RenderContext ‑> Void> = new Event<RenderContext>()
onRender:Event<Void ‑> Void> = new Event<Void>()
type:RendererType
window:Window
create ():Void
flip ():Void
readPixels (?rect:Rectangle):Image