FREQ - Set a light to be active but not illuminate

Hi,

I think this would be a nice feature to have, to use in conjunction with Box2D and sensors. I was able to get the polygon made from the lit area of a light, and use that to create a Box2D body, fixture and sensor from this. However, this makes it reliant on the light being active before being able to get its shape, and sometimes, I don't want the light to be lighting anything, especially when I use the same system to carve out fog of war. Transparency is not an option a lot of imes, because of the blending involved with FoW etc. The best way would be a toggle to keep the light active, but not giving off light, while still interacting (raycasting) with Box2d objects.

An application for this feature would be toggling the light source to shed light, when an entity steps into its sensor range. In my specialized case, once a light starts illuminating, I can combine it's light field to the character's vision field, to create the actual visual area, and trigger/update all reliant controls, e.g. minimap, game events etc.

On a side note, I saw a FREQ for the ability to shed light to an FBO. I could perhaps use that to calculate light fields, cache them, and switch the lights off, although I think my FREQ is a simpler one to implement, and more accessible to novice users.

Thanks.

Start by tracing how lights are marked active, how illumination is generated, and how Box2D sensors and raycasting interact with that state. Compare the requested toggle with the FBO-based approach mentioned in the issue. Done means a light can remain active for shape and sensor calculations without illuminating, while normal lighting behavior remains available.