how to make an interactive world map for conquest game

hello im trying to make a world conquest game where a player chooses a region to start with ten expands there empire to other regions and conquer them in till they own the whole world but my first problem is how am i suppose to create the world map i was going to use an image but i want it to be interactive and make different areas change color depending on the who controls the area then i was going to make 3d models of each region in blender then put them all together in unity but i cant model d continents right in the first place so idk how to make a interactive world map Plz help keep in mind its modern warfare so its not just land battles its also naval and air.

A solution commonly used for this problem is to make a mask that matches the aspect ratio of the map where each region you want to identify by clicking is a different color. You can then use the textureCoord in the RaycastHit structure to get the color and identify what region was clicked. Here is a question where someone is trying to do a map:

http://answers.unity3d.com/questions/462851/how-to-use-part-of-an-image-for-a-button.html

And in this question I provide some sample source for doing this hit testing (for buttons, though the concept is the same):

http://answers.unity3d.com/questions/516609/empty-spaces-in-buttons-are-detected-by-mouse.html

Hi!
This is the main reason I created World Political Map. This is an interactive geographic-based asset that provides what you need.
Take a look: Unity Asset Store - The Best Assets for Game Making

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