How to Avoid Object Intersection | Blender Geometry Nodes Tutorial

In this Blender tutorial I break down the RayCast Node in a Geometry Nodes network. The RayCast node can be used for multiple things, including telling Blender to avoid objects on the ground plane where we want to grow grass.

[samuelsantos]

Nice one! I just noticed it's possible to use "Set Position" just after the "Object Info" to slightly scale the rock's vertices in its normal directions just in the context of "RayCast". This way you can have an even better behavior preventing intersections. Just plug "Normal" -> "Scale (vector)" - > "Set Position (Offset)".

[RealGaryGibson]

FINALLY someone explains raycast in a way that I can understand it. Thank you soooo much!

[SpencerMagnusson]

Great implementation of the Raycast node! Love seeing more people experimenting with it and coming up with good solutions. One tip I'll mention is that the "Ray Length" property for the raycast node can be shortened, not just to accidentally hit hovering objects that may not count as an intersection, but it can also drastically improve performance when colliding with more or more complex objects. The performance hit is minimal with smaller meshes like this, but may be helpful for big scenes.
This is coming from someone who's used the Python equivalent of the Raycast in Blender for an add-on and learned that the hard way :) cheers

[contentwhre]

i must have done something wrong. using blender 3.2.2 and all points disappear when i add the raycast, when i add the NOT bool, all points show even in the sphere? :(

[gordonbrinkmann]

Great basic tutorial on the Raycast node. Just a quick tip, when you hoped the points would be visible enough in the video, there is a Set Point Radius node which could make them larger and much easier to see in the video. Setting the sphere to wireframe or bounding box while leaving the viewport in Solid mode would have also helped and saved you always switching between modes.

[DavidWinstead]

Wow, that's very useful man, thanks for sharing your demonstration!

[nswij]

This is exactly what I was looking for! Thanks!

[iraisynn.attinom]

very nice! thanks! will implement it in my addon (ia scatter) asap. also, connecting a normal node to the ray direction input makes sense for both horizontal and vertical surfaces

[kazes]

I just discovered the Proximity Geometry node and I was wondering if we could achieve the same effect with it?

[kazes]

This is super cool and usefull for my project which is generate old stone houses. The wall ares mades with stones not the same sizes and shapes and no mortar, so I wanted them to scatter on wall faces but not overlap. Thanks!

[stephanepolin]

Thx a lot, very good and simple tuto for GN raycast

[DamianPatkowski]

Is there a way to create a pile of rocks so I'll have a collection of big rocks, 2nd collection of middle ones, and 3rd of small and these objects inside the collections will not intersect each other?
I wonder of is there an option to randomly create a pile of rocks where big ones are in the center, middle around, and smaller ones in small holes or outside.

[wildguardian]

Is there a way to use this in order to make every geometric shape randomly distributed into the instance points not to touch itself? "distance min" isn't good enought.. either too distant or then it clips elements when distance is setted as too close

[paulopma]

Hello. In this case you avoid collision of two different collections. I tried avoiding collision within the same collection but couldn't make it, is it possible?
I'm new to Blender, thx for your videos.

[abandonedcranium]

Very helpful video, although I still can't figure out something. This video demonstrates how to prevent an object from clipping into another object. I'm using "distribute points on faces" to place leaves on a tree. How do I prevent the leaves from clipping into themselves?

[Mr_SteveD]

Awesome, thanks. You can also get rid of all clipping by adding a scale elements node just before you realize :) It is the cheat method to get proximity!!!

[SkinnyBlackout]

Today I learned how to get rid of penetration.

[pcforgaming]

Now blender is becoming more powerful compared to houdini, Maya, 3dx, cenema4d

[AnthonyAragues]

thanks for this. I keep finding new uses for this node. Still have the big open question I came here for. If I instance on points, I want its instances to avoid colliding with each other. so far I managed to create some circular logic that errors :)

[sebastianosewolf]

why you jdont just added an object for the points before ? instead of "i hope you can see this little tiny gray on gray points ?