Thu, 11/03/2011 - 13:29
Forums:
I have to display some thousands of points(more than 1000000), and each point is assigned an unique color.
I tried to sovle it using some methods mentioned below, but they do not work well. Any ideas of how to to this?
http://www.opencascade.org/org/forum/thread_21359/
http://www.opencascade.org/org/forum/thread_1125/
Thanks in advance!
Fri, 11/04/2011 - 12:01
OCC is not IMO the best library for visualization or large data sets. You should have a look at some specialized libraries (such as VTK http://www.vtk.org/, http://mayavi.sourceforge.net).
Thomas
Mon, 11/07/2011 - 10:01
Thanks very much.
Wed, 11/09/2011 - 10:43
Hi Gao, I was able to do 2 million points on 32 bit and about 4 million points on 64 bit, but even if you draw all the points using pure opengl calls (you can do this by attaching a callback function in the user draw of group, which in turn calls opengl directly), you would want to do some optimization, like check if the point is visible by the cameras frustum and only if its inside it then draw the point, look into a software called Qsplat, he wrote everything in pure c++ and some techniques can be borrowed from all the papers published, he even did a version that downloads pointcloud data on request from a server in a non asynchronous manner.
Hope that Helps.
Best
Alex
Wed, 11/09/2011 - 10:45
i mean: ...server in a asynchronous manner.