Questions tagged [mathematics]
Use of maths inside blender.
438
questions
0
votes
1
answer
10
views
Calibrate a FirstPerson movement combination
Given a script that listens for key inputs and checks which keys are pressed, how should I deal with combinations like up and right ?
up will increase local Y velocity and right local Y, but if ...
- 699
0
votes
0
answers
25
views
documentation for Math Function -> XYZ Math Surface
I struggled to find any documentation on the definition of math functions for the module XYZ math Surface.
For example how is the "Tan inverse" written?
Thanks!
- 475
1
vote
0
answers
20
views
How to get a high peformance `not operator` in shader nodes?
In Is there a way to use logic operators in Blender Shader nodes? the answer provides a not operator however it uses a nand operator to achieve this which is too ...
- 1,189
0
votes
0
answers
26
views
How to test if a value is exactly 0.0 in shader nodes?
I have a node setup where I need to test whether or not a value is exactly 0.
Blender's math node has a comparison mode but it uses an epsilon value to check if a value is within a certain tolerance, ...
- 1,189
5
votes
2
answers
107
views
What happens when a vector is fed into a value slot of the add node?
I was wondering what happens when a vector is fed into a Math -> Add node. Notice that I'm asking about the Math -> Add node, not the Vector Math -> Add node.
My guess was that the node ...
- 101
1
vote
0
answers
18
views
Difficult to phrase blender problem with a rig using the tangent function
What I want to happen, when I move the target bone, is for the Child bone to move only on the X and Y axis, NOT THE Z.
I figured I would use the rotational values of the constrained bone as drivers ...
- 11
4
votes
3
answers
81
views
How to get Circumference of Corners or Outer Edges? (Geometry Nodes)
I want to ask if there is any geometry node for getting the circumference of the corners or "outer edges" of a mesh.
I'm very new to geometry nodes and have been trying to make cake where ...
- 43
-1
votes
2
answers
112
views
Control over attributes of individual objects of a collection info node (part 2)
I have tried to implement the advice from a previous question, combined with controling the density of each instance on points. However, I still can't quite figure it out. I have done the following:
...
- 191
2
votes
0
answers
17
views
How to get the exact distance to the closest edge from voronoi texture?
The voronoi texture itself comes with a distance to edge option, however it only lets you use the euclidean distance to edge. What I want is the distance to edge for the Manhatten and Chebichev ...
- 1,189
7
votes
4
answers
191
views
Geonodes mix position with random index values - How to make random values unique?
I'm animating a Mix-RGB position change in a geonode setup that shifts an instanced plane from 2400 grid vertices to a different series of grids that add up to an equal 2400.
The mix animation didn't ...
0
votes
1
answer
20
views
MATH: Using sine w/frame count to dictate emission
I have 2 scenes at 35 fps (yes, non-standard)
Scene "L" 175 frames:
5 sections of 35 frame each
Emission should turn on/off once during each 35 frame interval per object
There are 5 objects, ...
- 11
0
votes
1
answer
33
views
How does the topology in Blender relate to the mathematical topology?
In many videos of Blender that I have seen, it goes over the topic of "topology" what I seem to think it is about is about setting a grid line on the surface / seeing the inverse of the grid ...
0
votes
1
answer
36
views
Getting the vector of specific vertex indexes and performing math using geometry nodes
Getting the vector of specific vertex indexes and performing math using geometry nodes.
My goal is to get the vector of specific vertices of an object and perform math. I'm having trouble getting the ...
- 2,610
0
votes
1
answer
32
views
Is it possible to get two Voronoi textures, F1 and F2, to use consistent colors for points?
In other words, if F1 returns point X as closest, and another F2 returns the same X as closest, is it possible to ensure that they are always set to the same color?
I assumed this would be the default,...
- 1,081
1
vote
1
answer
50
views
How do I get the minimum value of a node?
There is a range of values coming out of the length node as shown below, and I want to capture the minimum value out of all of them.
Any idea how to do this?
Thank you!
- 31
1
vote
1
answer
81
views
What is the fastest way to set global vertices coordinates to a numpy array using bpy?
The fastest way I know to get the vertices coordinates from the mesh is to use .foreach_get() method:
...
- 1,180
0
votes
3
answers
55
views
Geometry Nodes Equation/Method for bouncing objects?
I would like to have a bunch of cubes bounce in a specific space. I have set up a simple equation of abs(cos(x))/x which terminates after 3 bounces. It looks kinda ...
- 1,103
3
votes
2
answers
283
views
Unfold cylindrical object around rotation axis
Good evening!
Sometime ago i asked a similar question but i did not get the right answer and the discussion went into a wrong direction. Maybe i did not express myself correctly.
That's why i did a ...
- 41
5
votes
1
answer
396
views
Using math nodes to create geometry in geometry nodes
Using math nodes to create geometry in geometry nodes
I'm trying to create some geometry using math nodes in geometry nodes see image below of what I'm trying to create. Yes I know I could model a ...
- 2,610
10
votes
4
answers
1k
views
How do you draw sin, cos and tan with shaders?
I want to draw sin, cos, tan and other mathematical functions with the shader editor. How do I do this?
- 1,254
0
votes
0
answers
55
views
0
votes
0
answers
30
views
Faking acurate reflections with an environmet texture on a model with a normal map
So, I've tried making cubemap-like reflections on a model with an environment texture (the ones that come with blender for now).
The sphere on the right has just the regular reflection from the ...
3
votes
1
answer
168
views
Selecting every n'th index between the numerical index ranges of b and c using modulo in geometry nodes
This question is similar to Selecting every n'th index using modulo in geometry nodes but with an added range option.
I can select every n'th number thanks to Hulifier
I'm trying to select every ...
- 2,610
1
vote
2
answers
49
views
If there is any way in Blender I can use a mathematical formula to control particle density?
I'm trying to visualize something in physics. I have a formula that determines the density of particles at each point in 3D space. How can I visualize this?
For example: density=1/r^2
- 11
4
votes
1
answer
265
views
Selecting every n'th index using modulo in geometry nodes
How can I go about selecting every n'th index using modulo in geometry nodes.
Example: I have an index range of 0-35 and would like to select every 9th index so I can place an icosphere on it, which ...
- 2,610
4
votes
4
answers
184
views
Geometry Nodes Fields - Semi Circle
Is it possible to create a semi-circle with Geometry Nodes?
It's for a particle system, so a math based approach rather than a boolean approach would be ideal to keep the vert count/calculation time ...
- 184
0
votes
2
answers
55
views
How to create Sine "Pulse" with math nodes and "From/To" inputs Amplitude?
Based on this answer:Sine wave using only Math nodes?
I have the ability to create an animated waveform with an amplitude from 0 to 1.
Very interesting and useful.
But now I would like to ask the more ...
- 955
0
votes
0
answers
45
views
Need help translating a mathematical formula to nodes
Recently I went deep into the shader nodes rabbit hole, and just straight up started recreating the code for all kinds of fractals, raymarchers, ray-tracers and even path-tracers in shader nodes in ...
1
vote
0
answers
39
views
Geometry Nodes: How to calculate Custom normal deformation from real Normals?
AFAIK There is no Custom Normals at moment in GN.
As a workaround, Custom Normals can be baked into Vertex colors.
Which works great... until the mesh gets deformed.
Is it possible to calculate in ...
- 615
2
votes
1
answer
116
views
How can I transform my coffee cup into a torus as seen on wikipidea?
I'm animating the coffee mug torus homeomorphism.
I want my animation to match this gif as closely as possible.
The gif above, along with the POV-ray code used to create it, can be found here:https://...
- 334
2
votes
2
answers
50
views
1
vote
4
answers
82
views
Help with math formula to maintain distance along the x-axis between an Outer cube and an inner cube of 0.88 while scaling
Help with math formula to maintain distance along the x-axis between an outer cube and an inner cube of 0.88 while scaling.
...
- 2,610
0
votes
0
answers
27
views
How to properly combine Rotation Quaternion with Matrix for viewport/RegionView3D manipulation?
(Copy and pasted it from another place since I wasnt getting any replies)
Hi,
I am working on an addon that uses external application's touch gesture to send information to a socket, which then is ...
0
votes
1
answer
38
views
Sine offset of Vertices based on Position/Normal not Index
I am working on a Geometry Node System that can turn every simple mesh into cardboard with the infamous wave curve between both flat borders. I use the sine function for that and have a complicated ...
1
vote
2
answers
100
views
Calculating distance between two objects in Geometry Nodes
I need to calculate the distance between two spheres. The outcome of equation should be value determinating speed of moving object (Trying to implement II Kepler's Law). I managed to do something like ...
- 11
8
votes
1
answer
142
views
Get Wave Texture to Follow Empty
What I'm looking for is some way to get a wave texture to function similar to a dampened track or a track to constraint. I don't want to have to rotate the actual sphere itself,
just the texture to ...
- 149
11
votes
2
answers
571
views
How do I create a 3D parametric surface using Geometry nodes?
This question asked how to plot the graph of 2D parametric equations using Geometry Nodes. But how about parametric surfaces generated by parametric equations of the form
$$ x = f(u, v)$$
$$ y = g(u, ...
- 29.7k
1
vote
1
answer
40
views
How do you type a square root for the surface plotter?
For the "Add Z function surface" addon, I tried typing $(1 - x**2 - y**2)**(1/2)$ and $pow(1 - x**2 - y**2,(1/2))$ and neither plotted, what do I do differently?
- 215
11
votes
3
answers
621
views
How do I plot a 2D parametric equation in Geometry Nodes?
Summary: How to graph a 2D parametric equation using Geometry Nodes?
Details:
This question asks about plotting 2D functions of the form $y = F(x)$ using Geometry Nodes, and of course the simplest way ...
- 29.7k
0
votes
2
answers
155
views
Scaling objects with a constant offset with geometry node
I'm looking to find a way to scale objects while maintaining a constant offset. I found a way to do it with two objects, but I don't know how I could do it with 3 or more.
ex: (scale = 1) cube 111, ...
- 21
0
votes
0
answers
62
views
Is there a way to convert Map Range Smoother Step to Color Ramp B-Spline?
Map Range makes it possible to place the nodes inside the group and adjust them at its discretion due to the presence of several input sockets. In this, its advantage compared to Color Ramp, but Color ...
- 1
2
votes
3
answers
72
views
How could I make a polygon generator using shader nodes
I want to make a node group that outputs a polygon with a customizable size and side count.
I'm using arctan2 to make a setup that I figured would allow for a customizable side count.
If I add these ...
- 597
2
votes
2
answers
98
views
Non-proportional scaling in Geometry Nodes
I asked a question last week, and the answer way very useful, but I don't find a way to use this solution to scale more than 2 objects. So, is there a way to do it ?
The question:
I want to scale 2 ...
- 21
2
votes
1
answer
131
views
Exclude zero from "Random Value"
I want to return either a -1 or a 1 from the Random Value node. Unfortunately, I get either -1, 1 or 0! Is there a way to exclude zero from the results?
3
votes
3
answers
186
views
Geonodes: Curl a line with increasing curvature from origin
I'm trying to curl a line via GeoNodes. See here:
As you can see, the line stays fixed at its origin and then curls according to an angle/curvature parameter.
The length along the curve stays ...
- 43
1
vote
0
answers
35
views
Work out if vertices can be "naturally" connected
Given two vertices that are a part of one face, work out if they can be connected without creating weird geometry.
Example of vertices that can be naturally connected:
Example of vertices that cannot ...
- 99
0
votes
1
answer
36
views
Volumetric shader and re-create Schwartz Primitive Topology in Blender 3.1
I'm using eevee and trying to re-create Schwartz Primitive Topology found here Link but using Blender 3.1, however it's not working, any ideas why? My node setup is below.
Working Node setup:
My ...
- 2,610
1
vote
1
answer
77
views
In Geometry Nodes how can I transform an object proportionally with another object that's being controlled by an integer value?
I'm attempting to build a modular airplane hangar. In my current setup I have the hangar model split into the following 3 parts using vertex groups.
The front end
The hangar walls
The back end
The ...
- 55
3
votes
2
answers
160
views
Smooth Modulo with Nodes Only
Trying to get a smooth modulo texture based on nodes only, is this possible? The modulo function produces hard edges.
Similar to the following wave example: $$\frac{1}{t}\arctan\left(\frac{t\sin\left(...
- 196
0
votes
0
answers
110
views
Mapping a range of numbers to another range using math nodes / geometry nodes
How can I have numbers 0-360 be mapped to a range from -45 to 0 to +45 using math nodes / geometry nodes? I was thinking of using the map range node with a mod node but got confused.
I also looked ...
- 2,610