Click image for larger version. 

Name:	??.jpg 
Views:	115 
Size:	18.8 KB 
ID:	2409
The right four images are transformed to the left one, I do this in the shaders.
The vertices are like this:
Click image for larger version. 

Name:	???.jpg 
Views:	69 
Size:	6.4 KB 
ID:	2410


As you can see in the left image, there are seams in the red circles, so how to remove them in shaders.

gl version: gl es 3.0
raw image data format: rgb565