BaseCustomLayer draw is not hit

Question

I create an object derived from BaseCustomLayer which draws a polyline.
I call Map.addLayer(myBaseCustomLayer) and the function

public override void Draw(esriDrawPhase drawPhase, IDisplay Display, ITrackCancel trackCancel)

is hit. BUT if I set DynamicMapEnabled = true the draw function is not hit !

This is driving me crazy. Thanks for any hints.

Answer 1

Here's my understanding, based on this illustration from the documentation:

When the map is put into dynamic mode, a background image is created. Any "non dynamic" layers (those that don't implement IDynamicLayer) are drawn to a cache and used as a background image. OpenGL is used to quickly draw display lists on top of this background image. Therefore, I would only expect ILayer.Draw for a custom layer to be called once - when the dynamicdisplay mode starts.