Thinking about it again, they could probably add a new event for your request without having the cursor part of the game state. It's like a build event, just not successful. Yea that was my thought. If you're curious when those `on_load` events fire then you can read more here . And those are event...

Right now entities that use a sprite variations when placing will use the first sprite. However, for an entity that is non-square like 2x5 in size this interacts weirdly with rotation, as the first variation will not line up with all rotations of that entity. For example I have an entity that I want...

Not to mention, the cursor isn't part of the game state. Meaning it's not possible for a mod to do calculations on the location of an item in the cursor, because it would desync. In Factorio all clients do all calculations for all players. Meaning if you have Factory Planner installed, and your fri...

One problem for the entity to be red: it would have to apply *every time* the entity could be built by the cursor. Filtering for an item or entity specifically might not be bad for singular entities, but to check every entity in a blueprint every time the blueprint is moved would be extremely disru...

I will add I kinda have been wanting something similar hence this post here: viewtopic.php?f=28&t=103637

I would also like to add this would be quite helpful to have. For something I am working on this would be quite handy as well. Trying to figure out some way to work around the cursor being such a black box right now. Other than the cursor stack.

So my idea is pretty simple for the event. The event is only fired/called after all checks game normally runs determines an entity can be placed, but right before it passes that boolean result to the rest of the game. Then the handler for event checks whatever criteria it wants and just returns fals...