Hi, 
When experimenting with outlinetext, I found it generally works well for both text and equations but seems to fail for fractions or square roots. The code below demonstrates the issue: 
____________________________
\startMPpage
draw outlinetext("$\frac{1}{\sqrt{2}}$");
\stopMPpage
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The ‘1’ and ‘2’ seem to be at the right positions, but the fraction bar and horizontal part of the radical are missing.
Is there a different fonction I should use for getting the outlines of equations?

Best regards,
Florent