Curve radius presets and options
Many O Scale Locomotives and passenger cars require a minimum radius of O72. According to the creator of fastback most will run on as tight a cutie as O48 at reasonable speeds.
Allow users to preset a minimum curve of O72 with optional use of O60 and O48 curves in specific situations. Concurrently, display only the library for the minimum curve and above unless tighter radiuses are opted for.
A per-layout minimum radius constraint is scheduled for a future update
Sean Franklin commented
Running into this issue now, I'm using (like many modelers) only Flextrack and specific elements otherwise required - e.g. switches and crossovers. Then joining the elements with Flex, using the Control-F tool. But RailModeller will happily bend flex track to any ridiculous angle. What I'd want is to be able to set my minimum radius and have RailModeller adjust the flex as necessary - even using an "S" shape if that will let it connect - and if it won't, just let me know that it won't without violating the radius.
This should not be a "per-layout" constraint though, it should be something we can set as needed. My mainline minimum radius is 48" but my sidings can be much tighter.
A minimum radius constraint - optionally specified for each layout - is planned for a future update.
All layout constraints will appear as messages or warnings and won't prevent users from 'violating' them.