Geometry Nodes

I see, well currently if the output are scattered instances and you apply the modifier scattered instances get lost. There are two ways how to procede:

  • just press CTRL+A and pick Make Instances Real
  • Add any modifier that doesn’t affect your scattered instances(eg. Mask modifier) after geo nodes modifier, you’ll probably have to apply modifiers, not sure, haven’t tested that

thank you for the tip.
I had to “make the instances real”.

Update
If you have thousands of instances it become not a good way to do it.
I hope they’ll develop something clever for this.
Something like you can leave the geom node modifier and you’ll be able to use it for baking.

So, I’ve made a new tutorial focusing on Sample Texture and Attribute Maths to create a motion and VFX art. Portuguese only, but it’s pretty easy to follow I think. :smiley:

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I have been trying to setup a single geonode setup for morphing one mesh to another (with the same topology) without using shapekeys or other tricks. So far this does not seem to be possible given it is not possible to extract one set of attributes (position) from a mesh and plug it into another mesh in the same node set.

As far as I know there is no way to do this. One of the developers was writing of possible solution of similar problem but it was not covering this particular case. It looks like there is no even plans of implementation which would help to solve the problem yet.

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Now that Geometry Nodes are officially out, I have started a less technical/development-related thread over here if you feel like joining:

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The workaround to this issue that I have discovered is to connect your point instance node to a boolean node. You only need to connect into one input and it doesn’t matter which boolean mode you use. The other input can be blank. If you then use the apply command in the geonodes modifier, it gives you whole thing as one mesh without having to use the make instances real operator.

I have been making procedural rock generators by scattering low res meshes over a base mesh and then using a series of remesh and displace modifiers to get various procedural rock shapes. This technique was popularised with Houdini years ago and is quite a cool way of making rocks, etc.

This boolean hack works fine for a hundred or so instances, but will probably kill blender if there is a thousand! Anyway it is worth playing with until there is a dedicated make instances real node or equivalent.

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I’m curious, can you share any video about that technique?

Thank you…next week I’ll try with a scene I’m working on.

Not sure if you meant how it is done in Houdini or Blender, but here is a quick Houdini video that will give you the idea. I am planning on a Blender tutorial in the near future, but I can post a screenshot if that helps?

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Would using drivers solve this? So you could use the attribute as a driver for an other attribute in another geometry node graph?

I wanted to distribute my points accurately based on a custom texture without the necessity of subdividing the mesh.

So I created an identical object with the subdivision and copied it’s attribute texture sample result to my object with no subdivision. Object A actually has eight vertices and not four.

File attached.Point_Position Copied to Object_02.blend (1.2 MB)

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Here is a screenshot from a setup I created today in 2.93, though I am pretty sure it will also work in 2.92. It is actually a very easy geonodes setup, with the secret sauce being the list of remesh and displace modifiers in the stack that come after the intial scattering (which functions as the base mesh).

There is no right or wrong with these, just a matter of playing around till you get something you like. Just be careful with the multiple remeshers as they can be slow! I have also used a second geonodes scattering setup for the rocks. I am feeding the output of the first geonodes mesh into this second one and using the compare node to make sure the rocks are only on the +z axis, then remeshing again. This creates one single watertight mesh that you can decimate/remesh for a low poly version and derive a normal/ao map for gamedev.

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I think you can bake the coordinates of the first mesh into an image and sample that in the second mesh? (given that the two meshes have similar UV maps)

Edit: Tried it, works about fine except you have to add some value to the coordinates to get rid of the negatives

still in the end I have to feed it to something and that’s what’s missing. the only work around right now is to do it in one node. although now that I think about it I never tried node groups so that might be the better answer. (it’s same as doing it in one node but node group will stay the same on every node it uses it?!)

Yes, but that is not what I am looking for, that is just a work around trick and a static method. I would like to make it like a regular morph modifier. Back then I made a patch for an actual morph modifier that can be placed anywhere in the modifier stack but it was never accepted into the trunk. Basically trying to see if I can do it purely in the geonodes. This can be achieved with Sverchok or AN but the performance is not good with heavy meshes, so geonodes could have been a great performer for a morph modifier replacement.

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Could you go into a little more detail on how you achieved this? It seems simple enough, but I’m missing something in the geonode stage that prevents me from going any farther.

In short, I create two meshes. One instance, and one that I use as a volume for scattering the instances. I set up the appropriate nodes, get my results, but when I try to apply it to make it solid, my entire object disappears.

I’ve had a lot of bad luck today following what initially seems like simple instructions, so please, bear with me, and help me out.

My current hack to get around the “make instances real” workflow is to just feed what you already have into a boolean node before you go into the output node. No need to have anything in the second input. If you then apply the geonodes modifier it will give you one single mesh. You don’t need to apply any modifiers though until you have a final result, otherwise it would not be procedural! I would only start apply modifiers when I am happy with the result and want to create the high poly mesh, and derive a low poly to map onto.

Then after the geonodes modfifier start adding a remesh modifier at about 0.01 in voxel mode. Then various displace modifiers followed by another remesh modifier.
I took this a step further and created a second geonodes scattering setup to scatter rocks onto the resulting mesh from the first setup output mesh.

I still haven’t tried this on 2.92, as I use current master 2.93 but I think it should work.

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Geo Node “IN” (in-clude the modifier stack).
I hope this really clarifies everything. Great to have you on board @SteffenD.
I’ve been a Softimage ICE pilot for 10+ years. Imagine my joy on the evolution of (animation nodes) Geometry Nodes. :slight_smile:

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Nope, it doesn’t, hence my initial confusion. The resulting geometry from the geonodes won’t respond to any of the modifiers you stack on top of it in 2.92. If anyone wants to follow along with your tutorials, they’ll have to do so in 2.93.

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