I have a 1d texture with GL_NEAREST filtering.
I have also a textured mesh like the following picture:

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Name:	lala0.5.jpg 
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ID:	899

I'm trying to draw a black line (1px width) in between texture colors like the following picture:

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Name:	lala0.6.jpg 
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Size:	16.2 KB 
ID:	900

How can i achived that?