[BlenderBIM] clash detection first impressions
My first post here!
Below is the post from OSArch IRC forum. Hope it helps. More experiened users can add more points.
<I wanted to to check the precision of my 3d model and wanted to carry out clash detection. So I used blenderbim clash detection and a few other tools. After needing to figuring it out a bit I got bbim clash detection working. These are some points i found, not necessarily an universal issue. Also please note that these opinions are only mine and I am in no way criticising the addon itself.
blender version used 2.93.7 with bbim v0.0.220422
1) For me, the button "Add clash source" was a bit confusing, I was thinking that there is some .py file that needs to be loaded from the blenderbim user directory. So may be "Add ifc file" or "path to ifc file" would be better here? I figured it out after watching the tutorial video here https://wiki.osarch.org/index.php?title=BlenderBIM_Add-on_Clash_detection
2) Moving from one clash to the other seems to not exit at the moment. A way to navigate from one clash to another needs to be implemented in the UI.
-Open IFC viewer has a list view that one can double click.
-DDSCAD viewer also shows a list view and double clicking it highlights the clashed objects.
The issue in bbim is when highlighted objects are deselected, I was not able to re-highlight them. Running it again, didn't seem to do anything.
3) I think an option to choose the kind of clash would be good. Intersection type, Clearance type and any other, if any.
4) Getting back to regular mode after using "create snapshot" would be useful. Since I don't know how to do this with blender natively, I will have to learn it as an extra step. The whole model turns translucent and i don't know how to get back to regular mode from here. The snapshot itself has a lot of noise since all objects have the same transparency level and the actual object that has a clash cannot be identified properly even though highlighted.
5) Carrying out clash detection with all objects should also be possible, I don't know if it is present in bbim currently.
6) instead of adding syntax, which might lead to spelling and capitalisation errors, a list with a tick box would be extremely helpful. May be another option "clash all" can be provided here as well ?
7) When I press "Execute IFC clash" all objects that have a clash are selected, I don't exactly know where the clash is happening. This becomes important when the clash is less that a few millimetres. Again I find the automatic zoom to "clash object" and the way objects are highlighted with transparency settings in open ifc viewer very useful. Even the clip to clash option in DDSCAD viewer is good.
I have used DDSCAD viewer, open ifc viewer and blenderbim for clash detection of ifc files and Open ifc viewer seems to be the best of the 3 because it is the easiest to use. OIV has zero learning curve, however advance controls seem to be missing currently. For example, checking all clashes between only walls & beams, levels, etc are missing. It also doesn't highlight clashed objects in tree view which is crucial to create snapshots for making clash reports.
DDSCAD viewer is more advanced and needs a bit more learning but has a lot of features.>