No this is not advertisement and I post here how to do it for free now.
Neobook is an application to build all this easily with few drag and drops. All neobook applications are royality free, so you can use them with your commercial FPS game. Neobook has a plugin (also free)which can recognize images on your screen, Therefore, for each of your choosen trigger, you display any image on your screen (I recomend colors), and Neobook application (that you built), will detect it and display whatever you want. Unfortunatelly, I don't have time to take you step by step there, but Neobook forum has experts which canguide you. I think that neobook cost: $165. I repeat, this is not advertisement, I use neobook and FPSC and I got this idea with help of many other users form both applications on their forums. If moderator open a dedicated area for this we can continue working on this, for free, just I need time to answer due to I work a full time job.
Thanks, Javier
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