How to make a dynamicly revealing minimap

Im making a strategy game and Ive been fighting to make a dynamicly revealing minimap, cant make it work.

I’ve got a level and a Mini map static mesh actor that represents the same size as the level but if totaly black, and theres a camera-capture actor that captures every frame of this Mini map static mesh.

Controlled pawns spawn planes with relative offset on the mini map static mesh, those planes have white material with radial opacity mask.

The black and white mask that is produced every frame is being transmited to the black MiniMap Static mesh material.

The catch is that over it produces a memory leak that i need to clear those spawned white planes. But heres where the problem begins!

I have a two render targets that are in turn save captured mask image from the camera-capture-actor to add the missing detait.
But every i do the operation of deleting spawned planes, the image that camera-capture-actor produces is not the same level of colour I mean the new black and white data starts to fade out the old data, so over I lose information. And playing with the power, multieplier and clamp operations in the Material of the MiniMap mesh doesnt help becouse for some reason it makes an “explosion of exposure” effect.

For debugging I made the update proccess manual and clearing the spawned planes also manual. And Ive added image planes to the widget to see and debug the process, Ive binded keys to the events of the camera-capture-component using the level blueprint:

Is there any easier way to make a gradualy revealing minimap, just like in this video :

I’ll post my video showing what’s the problem in a bit.


Might seem away from what you are doing, but could you make mini map a widget, put lots of black images on it and make them transparent when area revealed?

Interesting idea, gona try that out, thank you! Does anyone else has an idea?