Validation failures should not prevent geometry from being built

[hannobraun]

There are various requirements that shapes must uphold, in order to be considered valid. Most of these requirements are checked as objects are being constructed (only most; there are open issues for missing validation checks). Always checking these makes sense, to prevent bugs or user error.

Currently, a validation failure leads to a runtime panic. Aside from not being user-friendly, this is fundamentally the wrong behavior. The error messages from validation failures are often not bad, as far as error messages go, but they are still text-based. This makes understanding them very difficult.

What would make them easier to understand, is to see the invalid shape graphically, which is exactly what validation failures currently prevent. Eventually, it would be great to show the validation error graphically, pointing exactly where something is wrong. For now, it'll be enough to display the invalid geometry and show the validation error as a status message.

[hannobraun]

This issue is no longer applicable. The affected code has been removed. See A New Direction for context.