Hi, I wonder if some one give me some idea on how to cut and merge mesh without affecting its texture mapping. e.g. merging like blender array and cutting like blender boolean features. by merging means I need to merge connecting vertices to reduce vertices count. e.g. I have 2 cylinder ends with 10 vertex points, 1st ends with 2nd start. so the overlapping vertices needs to merged. If I scale mesh than applied texture should repeat instead scaling along with mesh.
Well you’ll have to look into how vertex buffers, index buffers and UV buffers work, then it should become apparent how you can achieve what you want. Check the “custom meshes” tutorial in the manual or wiki.
Thanks normen, can you suggest any quick and easy tutorial for index buffer and UV buffer? do I need to learn GLSL for it?
No you don’t need any GLSL code for this, its simple data structures. The index buffer basically says which vertices in the vertex buffer are used and in which order they are used and the UV buffer basically gives an x/y coordinate on the texture for each vertex.
may be I’ll have to play around U/V index buffer.
Is there any way to pick vertex in point mode and pick line in line mode and highlight in different shade on mouse click?
Open Blender. Edit the mesh.
The SDK is not a model editor… that’s what Blender is for.
In short you mean to say there is no option. I know the SDK is not model editor but there is terrain editor with SDK. For large scene if SDK allows to let little model editing than I dont think its a bad idea.
Of course you can do this in code, e.g. with a separate viewport where you add the lines and points you select. And when you’re done you can also contribute a mesh editor for the SDK if you want 
I concur with Normen: we look forward to your patch submissions.
Sure, If I build something productive, I’ll contribute it in SDK. 
I just want to know, how can I change color of point or line on selection or mouse hover.
Which part don’t you understand?
Mesh in point mode, we can see number of points. out of these points if I want to show some points in different color. how can I do it?
In your app or in the scene editor?
Either way, given the information provided the answer is “write some code”.
ok, once I prepare some code I’ll show you.