My bad for not logging for a while, there js wasn’t much to show for outputs, and tbh, there still isn’t too much.
So, I finally got the details for all molecules working. The PubChem REST API is now pulling in coordinates, bond information, and chemical formulas for everything, and I’ve got 7 unique molecules across 37 annotated objects in the test scene.
After that, I started building out the actual simulation side. First step was getting a single molecule to render in Panda3D with proper CPK coloring and bond visualization. That worked surprisingly well. You can see the second image, that’s the single molecule.
Next, I tried just stacking them one on top of the other, spamming them in XYZ directions, but it didn’t really look realistic, so now I have to go the long route. I needed a way to place thousands of molecule instances without duplicating all the coordinate data, so I built a whole state machine system. There’s now a MoleculeTemplate class that holds the immutable chemical structure, and MoleculeInstance that just tracks position and rotation. One template can have hundreds of instances pointing to it.
Then I wrapped that in an ObjectState class to handle each annotated object from the scene (like “books” or “desk”), and an Environment class to hold all of them together.
The idea is you load the bounding boxes from the annotations, and for each object, you populate its volume with molecule instances based on the material composition.
I also spent way too long refactoring type annotations into a central file and making a constants module for element colors and radii. The CPK color mappings were duplicated in three places and it was lowkey pmo.
Next up:
Need to make the molecule placement actually realistic. Need to add randomization, collision checking between neighboring instances, and probably some basic force field approximations to make molecules settle into reasonable configurations.