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BBF
04-06-2004, 04:03 AM
I want to reduce my object's vertex number dynamicly in the program but I can't find any way
to do it,here's a function in the DX but I do not want to use it in an opengl program.
And I can't find any document about it except for the terrain^How can i do it for ordinary object??
Thanks for any help

capn_midnight
04-06-2004, 07:27 AM
personally, I would start by defining a vertex object, that I can assign a weighted value to. When I render my scene, if a vertex is more than a certain distance away, and it's weight value isn't high enough, then I would abstain from rendering that vertex. Now, this is a lot of work on your part, because you have to be able to figure out which vertexes can be eliminated at far off distances.

BBF
04-07-2004, 01:00 AM
But the problem is that it's complex to rebuild the face list after I elimated my vertex array.
And I have no idea of how to do it in an ordinary object at all

capn_midnight
04-07-2004, 05:13 AM
http://www.ship.edu/~sm8236/other/lod.png
okay, here's an idea that popped into my head involving binary trees. the numbers indicate levels of detail. One of the points in the white triangle is the root node of the tree, and the other two points in the triangle are the child nodes of the root node. Each of those child nodes is the parent node to one triangle at level 2, with two child nodes of their own to make 3 new triangles (3 of the points are duplicates). And it continues on down, recursively, until the shape of the circle is approximated.

BBF
04-08-2004, 11:24 PM
OK,I'v got it!Thank you very much

BBF
04-09-2004, 12:36 AM
See this
http://cc.zju.edu.cn/uploadfile/20044917295234028.jpg

and next
http://cc.zju.edu.cn/uploadfile/20044917293612170.jpg

:( :confused:
I can't connect the triangles correctly