Draw outlines effects like Civilization 6 map

cocos2d-x C++
#1

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I’m using kind of tile map in my 2d games. How to outline a merged area like the effect showed here? Using shaders?

Thanks very much.

#2

I would probably use waypoints and just draw a line between them.

#3

Sorry, what’s the meaning of “waypoints” here? It’s an existing class? a technique?

Further more, besides draw lines, how to draw the round corners?

#4

a technique: https://en.wikipedia.org/wiki/Waypoint

For rounded corners you could use opengl or sprites or, or, or