clean up pointmass render code

[vitchyr]

• remove render enable. Just call render with a specific mode.
• remove duplicate draw code

[snasiriany]

What is the context for these changes? From a quick look, I wasn't able to understand the motivation for the PR.

[vitchyr]

Did you see my first comment? It removes duplicate code and render_enable, which I think isn't particularly clean and isn't necessary.