Can decimate be done just on non detailed areas ?

[Steve003]

Hi,
decimate mesh spoils detail on areas that need the fine mesh, but its wrong to end up with so many faces causing my CAD prog to takes ages to do anything with the mesh , when there are planar or non detail areas not requiring thousand of minute polygons.

Is there a way to reduce the faces intelligently ?

Am I right in thinking such reduction is best done in the prog that holds the source photos ?

Could my CAD prog if it has more intelligent mesh revision be used if it has the texture .jpg applied in materials >allocate by object, browse to jpg, (need to do per viewport) carried out ?

Steve

[jenkinsm]

Here's what I would do (I'm working towards the same goal):

1) Build dense cloud with as much detail as possible
2) Select the areas that you want to have less detail and assign a class [Ctrl+Shift+C]
3) Generate the mesh one class at a time and set the detail level for each according to your needs.
4) Combine the meshes

There might be other ways of doing this, but this is what I've thought of so far. You can also use Tools>Dense Coud>Classify Points... to automatically classify points based on object type (cars, road, vegetation buildings, etc.) but that's been a bit hit-or-miss for me.

You might also be able to select portions of the finished hi-poly mesh and separate them into their own chunks, then decimate those pieces individually. But I don't know how well it will preserve the edges of the chunks so you might have issues combining them. Someone with more experience (or the patience to test it) would be able to tell you if that would work.