Donna L Gresh wrote: > > I gather that you want the specific functionality that maptoplane > provides in creating just the right triangles that match the > cubes or tets of the original 3D field? Because you can certainly > just define a line (using two points to construct) and then refine > it to a level that works for the data set, then map the 3D data onto it. > Or are you mapping 2D data in 3 space and that's the issue? > > _________________________________ > Donna L. Gresh, Ph.D. > Visual Analysis Group > IBM T.J. Watson Research Center > (914) 784-5049 > [EMAIL PROTECTED] >
I'm looking for the specific functionality of MapToPlane. Basically, I want to shoot a ray through a dataset (in this case, a 4M Tet CFD simulation). If I refine to a level fine enough to put at least one sample in a tet at the boundry layer, I oversample 90% of the other tets by a factor of 1000. The application is for a volume render that runs inside of RenderMan. I've written a shader that use CallModule to compute the color and opacity at the requested point. I also have a slice shader. You pass to the the shader the dataset name and a colormap and dx computes the color. Pretty cool. However, the shaders are slower than molasses on tetrehedral grids (not bad on regular). For the slice shader, it's just doing a Map on the point generated by RenderMan. Since each point is taken in isolation (there is no assumption of the point being on a plane, the "surface" being shaded could be a cylinder for instance), you pay a massive overhead for the cell search. I think the best thing for me is to write a new module that would cache the point and start the search for the next cell from the last cell. Ideas? Mark -- Mark Bolstad Lockheed-Martin Services Inc. [EMAIL PROTECTED] (919)-541-3604
