How to render hidden lines of OutlinePass as dashed lines?

Is there any way to set hidden outline to dashed line? I can not set dashed line by caculate distance from position in outlinePass.js’s shader.
Website: https://threejs.org/examples/?q=outline#webgl_postprocessing_outline

I’m sorry I didn’t make myself clear. In the picture below I want to render the hidden line to dashed line. Is it feasible? Thank you very much for your help.

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