Hi everyone,
I’m new to TouchDesigner and have been experimenting with point clouds. I am looking for a way to use 2D or 3D shapes to select parts of point clouds to apply noise, transform, hide, etc. I have seen some tutorials that achieve this using a threshold but I would like to find a way to use something like a cube or a 2d shape to select only a portion of a point cloud. The pointField comp seems like it it could be used to achieve what I’m looking for but i can’t find any tutorials, any recommendations would be much appreciated!
What you’re looking for is the second input of the pointTransform TOP.
Said input is the “Weights” input which acts as a sort of “filter” to let you decide what to apply transformation to and what to leave unchanged.
In the same section of the Palette where you found the pointField COMP you can also find the pointGenerator as well as the pointWeight COMPs (this second one has sadly never been updated) which can both be used as filters of your pointCloud (resolutions should be the same for the two inputs of the pointTransform).
If you wanna mask a certain 2D shape, you can use a second pointcloud that contains the shape you wanna use and is placed where you would like to “carve” your first pointcloud at and use it as your Weight input (I believe you could use a reorder TOP to turn a 2D texture into an RGB channel [I haven’t done it in ages but I strongly believe it can be done, just needs some patience] ).
Some good resources could be rgbmath in Touchdesigner and sculpting with height maps in Touchdesigner by paketa12 (as well as many other videos available on his channel).
Hope this clears some of your doubts.
This is all very helpful, thank you for the detailed response!