Where to Begin in Geometry Nodes: Vector Math

[@ryut]

This kind of lesson was what I had been seeking for a long time. I always want to learn the principles under the hood but the majority of tutors teach only which button to press. You are amazing Thank you so much!

[@looseEdges]

You're welcome!

[@sander-wit]

Thanks so much for taking the time to explain these nodes, I am certainly going to recreate your simple setup with the arrows to see if I actually get it, but I think I do. I think seeing some practical use cases might help understanding these nodes even more, but I love that you took the time to make this video. 🙏

[@leahthegeek9677]

This is a really interesting explanation of vector maths that goes into details and I love it! Thank you so much.

[@fxnoob7486]

Thank you

[@JohnSatan]

Little advice for geometry nodes begginers, use frames and add labels to them with short description for every step, it greatly helps in arranging node setups and help you reading it later

[@looseEdges]

I think frames are fine if you prefer them, but I have a slightly different take on this. If there is a part of your graph that is too complicated to understand at a glance, I would group it and name the group rather than framing it. Groups have the added bonus of being easily reusable in other nodes.

[@JohnSatan]

@@looseEdges they does, but still doesn't improve readability, and i'm talking about small groups of nodes that all doing some unique stuff, like 3 nodes that just transfer some attribute, or like 8 nodes that converting marked edge to curve, arranging and framing them greatly improve readability, like i open my own old project and doesn't understand and thing in that tangled mess, with labelled frames i can return to old setup at any time and easily recall what doing what, and update that setup. Frames just super convenient. It's like taking notes or commenting your code. Groups for big stuff, frames for small stuff. Another convenient thing is that you can put text into frame, i can literally put documentation for my node group into node group itself, and if want to find what that particular slider do, i just tab into node and find entry for that slider with some additional hints

[@fergadelics]

Blender official has a free note/ annotation addon tool. It nice to be able to leave notes without all the hassle of having to write a note in the notes editor then attaching to a frame in gn or shader editor.

[@JayeshSarvaiya]

Thank you so much for these videos and your efforts to make them, Geometry nodes are difficult for me to begin with as they are not very intuitive as compared to modifiers, at least in modifiers we can mess around to se what can be done, its visual, but with geometry nodes there are lots of if's and but's, I am learning from various channels but still going through steep learning curve... Hope to have grip on it someday...

[@aliensoup2420]

This is a nice visual or geometrical explanation of vector operations, but it evades the mathematical essence of the concept. The geometric picture will only get you so far, and not very far. The underlying math will get you everywhere. There is no shortcut to understanding vector math...you HAVE to do the math. There are countless videos and short courses on KZbin. Khan Academy is a good start.

[@satishgoda]

Brilliant!

[@hectorescobar9450]

This is interesting and all, but I wonder if there is a way to translate this information for artist or in artist use cases language. I personally find it difficult to join the dots beginning from a vector to making a building or how it co relates to normals, faces and Vertices. Or maybe how to construct something cohesively into some easy to understand structure.

[@GaryParris]

great

[@goranradojicic6652]

Hello, instead of 0 and 1 can I use cm or in ?

[@looseEdges]

Hmm, I'm not sure what you mean exactly, in blender 0 and 1 would be 'blender units,' by default those are mapped to meters, you can change the default unit to something else in the Scene tab of the Properties panel under Units. On distance properties you can type in '5in' or '2cm' in the text box but after hitting enter that will be converted into whatever the scene unit is, so 0.02 for the default of meters.

[@simonw.1223]

for me this was simple but how did you do the arrow I know a line with two vectors as endpoint but tike the two other lines?

[@looseEdges]

The first endpoint is shared. To find the other, I subtracted the end points to get a direction vector, took the cross product of that direction and up to get a perpendicular vector, normalized the result, normalized the direction, added the result to the direction, then added a scaled amount of that vector to the endpoint.

[@simonw.1223]

@@looseEdges I dont get it. Like rn watching the vector math pt 2 and I get what you mean but in this comment I dont really get it.

[@simonw.1223]

@@looseEdges btw I made a similar arrow so I can play like this in the video and I see also that the two vector create liek an infinte 2d plane and you put the dot product above or below it.

[@Geistplan]

Hello, I bought your node. Can you please help me, I can't figure it out: I would like to display the value of a counted vertice in a different color. For example, if it is an even number it should be green, if it is an odd number it should be red. How can I proceed?

[@looseEdges]

You can achieve that using a math modulo node. Index modulo 2 will equal 0 for all even numbers and equal 1 for all odd numbers. If you plug the result into a color mix node or a switch node you can choose the two colors to alternate.

[@Geistplan]

@@looseEdges Thanks a lot for your tool and your answer!

[@PedroScherz]

How do I find the vector(X,Y,Z) of a particular vertex and use it as an input?

[@looseEdges]

Probably with the Sample Index node. Could also look at Sample Nearest. Just connect Position as the attribute to sample.

[@PedroScherz]

@@looseEdges I got it working. Yes it’s the sample index node, I forgot to add the position input. Thanks

[@hakankosebas2085]

can simulation nodes do rigid body dynamics and collision?

[@looseEdges]

No, not really. You might be able to make bouncing balls, but I don't think there is a good way to handle multiple contacts. In any case, I think it would be too complex and slow to be practical.

[@hakankosebas2085]

@@looseEdges ı need to spawn objects with every x frame, how can I achive it then without particles? particle collision seems to unrealistic

[@looseEdges]

@@hakankosebas2085 For spawning, you can use instance on points in a simulation zone. You can run the points it will instance on through a switch node, this will output points on every 'Xth' frame and nothing otherwise. The boolean value of the switch node would be connected to a sequence of nodes. Scene Time: Frame; to a Modulo Math node; to a compare equals node. The value on the modulo node is 'X', (so 2 for every other frame) and the equals can either be 0 (to output TRUE on the first frame) or any value less that 'X' (to output TRUE on a later frame) danielhickox.com/img/spawn_points.png

[@hakankosebas2085]

@@looseEdges thanks