[NTG-context] Using metapost stuff in ConTeXt

Suppose I have a .mp file foo.mp, which contains some shared definitions and two images: beginfig(1); % some stuff endfig; beginfig(0); % some other stuff endfig; If I run mptopdf on this file I get foo-0.pdf and foo-1.pdf. And that works fine. But can I somehow interface directly from within ConTeXt to these images without doing the mptopdf myself in a way that the ConTeXt tools maintain the mp->image process, that these images are only recreated when the .mp file has changed and not on every run? Thanks, G