Blender Tutorial: Geometry Nodes for Beginners - Part 1

Summary

This tutorial introduces Geometry Nodes in Blender, a powerful tool for artists to create complex 3D models with ease. The instructor walks through the basics, explaining how Geometry Nodes function as a modifier and can be used to manipulate mesh data. The video demonstrates creating a sugar-coated candy effect on a cube by scattering points and using them to instance smaller cube objects, which represent sugar crystals. Key concepts like joining nodes, applying transformations, and randomizing properties are covered, providing a foundation for more advanced Geometry Nodes techniques.

Takeaways

• 🎨 **Geometry Nodes as Artist-Friendly Programming:** The script introduces Geometry Nodes as a tool that allows artists to perform actions based on defined rules, enabling the creation of complex or previously impossible designs.
• 📚 **Learning the Basics:** It emphasizes the importance of learning the core functionality of Geometry Nodes, which is the focus of the tutorial series.
• 🔧 **Geometry Nodes as Modifiers:** The script explains that Geometry Nodes function as modifiers in Blender, similar to others, and their order in the stack matters.
• 📦 **Understanding the Geometry Nodes System:** It's described as a post-processing tool for meshes, where the input is the mesh and the output is the result of the node operations.
• 🔄 **Transforming Meshes:** The tutorial demonstrates how to use Geometry Nodes to transform meshes, such as moving, rotating, and scaling, without actually altering the mesh data.
• 🍬 **Practical Application:** The script outlines a practical application of Geometry Nodes by creating a sugar-coated candy effect on a cube.
• 🔍 **Using the Spreadsheet:** It mentions the spreadsheet, a feature that shows the coordinates of vertices and faces, which is useful in specific cases but can be hidden for simplicity.
• 🔗 **Connecting Nodes:** The process of connecting nodes is explained, highlighting the importance of matching colors to ensure data flows correctly.
• 🌐 **Scattering Points on Faces:** The tutorial covers how to scatter points on the faces of a mesh using the 'Distribute Points on Faces' node.
• 🔄 **Joining Geometry:** It introduces the 'Join Geometry' node, which allows for multiple inputs to be combined into a single output, a powerful feature for complex setups.

Q & A

What is Geometry Nodes in Blender?

Geometry Nodes is a node-based system in Blender that allows artists to create and manipulate geometry through a visual programming interface, enabling complex tasks and custom tools for faster production.

Why should artists learn the basics of Geometry Nodes?

Artists should learn the basics of Geometry Nodes to expand their capabilities, enabling them to create effects and tools that were previously impossible or difficult, thus streamlining their workflow.

How does the order of modifiers affect Geometry Nodes in Blender?

The order of modifiers in Blender, including Geometry Nodes, matters as they are applied top to bottom. For instance, having a Subsurf modifier before or after Geometry Nodes will result in different outcomes.

What is the role of the 'Spreadsheet' in Geometry Nodes?

The 'Spreadsheet' in Geometry Nodes displays the exact coordinates of vertices and faces, which is useful in specific cases but is often hidden as it can be overwhelming for most users.

How does the 'Join Geometry' node function in Geometry Nodes?

The 'Join Geometry' node allows users to combine multiple geometry inputs into a single output, which can be used for various purposes, such as using the same mesh data for rendering and creating points.

What is the purpose of the 'Distribute Points on Faces' node?

The 'Distribute Points on Faces' node scatters points across the surface of a mesh, which can be used as a basis for more complex operations, such as creating detailed textures or particle systems.

Why is it necessary to apply transformations in Geometry Nodes?

Transformations such as scale, rotation, and location must be applied in Geometry Nodes by pressing Ctrl+A to ensure that the modified values are used correctly in subsequent nodes and operations.

How does the 'Instance on Points' node work in Geometry Nodes?

The 'Instance on Points' node replaces the scattered points with instances of another object, which can be used to create effects like scattering objects across a surface.

What is the significance of the 'Random Value' node in creating random rotations?

The 'Random Value' node generates random values between zero and one, which can be used to create random rotations for each instance on points by plugging it into the rotation inputs of the 'Instance on Points' node.

Why are radians used in Geometry Nodes for rotations?

Radians are used in Geometry Nodes for rotations because they are a standard unit in mathematical calculations. One radian is approximately 57.29 degrees, and using radians allows for precise and consistent mathematical operations.

How can you ensure that instances maintain a cubic shape when scaling?

To ensure that instances maintain a cubic shape when scaling, use the 'Random Value' node to generate random float values and connect it to the scale input of the 'Instance on Points' node, making sure all axes use the same scale value.

Outlines

00:00

🎨 Introduction to Geometry Nodes

The paragraph introduces Geometry Nodes as a user-friendly programming tool in Blender that allows artists to perform actions based on defined rules, enabling the creation of complex or previously impossible designs. It emphasizes the importance of learning the basics, which is the focus of the video series. The tutorial begins with a new scene and guides viewers through accessing the Geometry Nodes tab, explaining the initial setup involving a 3D viewport and the 'spreadsheet' that displays vertex and face coordinates. The instructor suggests hiding the spreadsheet and demonstrates how to apply a Geometry Nodes system to a cube, introducing the concept of modifiers and their order. The core functionality of Geometry Nodes is likened to post-processing for meshes, with an example of how to transform the cube using the nodes without altering the original mesh.

05:00

🍭 Creating a Candy-like Texture with Geometry Nodes

This section delves into using Geometry Nodes to create a sugar scattering system on a cube to mimic a lollipop or candy appearance. The tutorial explains how to add nodes and connect them correctly, focusing on the 'Distribute Points on Faces' node to scatter points across the cube's surface. The instructor discusses the rendering of points and introduces the 'Join Geometry' node to use the cube data twice—once for rendering and once for scattering points. The 'Instance on Point' node is then used to replace the scattered points with an object, in this case, a smaller cube referred to as a 'sugar crystal.' The process of scaling down the sugar crystal, applying the scale, and ensuring it is correctly referenced in the Geometry Nodes is also covered, setting the stage for creating a detailed candy texture.

10:02

🔄 Randomization and Transformation in Geometry Nodes

The final paragraph focuses on adding randomness and variation to the scattered objects using Geometry Nodes. It starts with the use of the 'Random Value' node to generate random rotation values for each sugar crystal, explaining the difference between radians and degrees and how to adjust the rotation range. The tutorial then moves on to scaling, where it's important to maintain the cube shape of the sugar crystals by using the same random value for all axes. The concept of 'tau' (2π) is introduced to create a full rotation range. The paragraph concludes with a teaser for the next part of the series, which promises to explore more advanced features of Geometry Nodes.

Keywords

💡Geometry Nodes

Geometry Nodes is a node-based visual programming system in Blender that allows artists to create complex geometry operations and effects without writing code. It's described as artist-friendly programming, enabling users to perform actions based on rules they define. In the video, Geometry Nodes are used to demonstrate how to create a practical sugar-coated candy, showcasing its capability to perform tasks that were previously impossible or to build tools for faster production.

💡Modifiers

In the context of the video, a modifier is a feature in Blender that can alter the geometry of an object. Geometry Nodes are introduced as a type of modifier, which means their order in the modifier stack matters, as they process the mesh data in a top-to-bottom sequence. This is crucial for understanding how different modifications interact and affect the final geometry.

💡Spreadsheet

The spreadsheet in Geometry Nodes is a panel that displays detailed information about the mesh, such as the coordinates of vertices and faces. Although it's mentioned that it's not heavily used in the tutorial, it's a useful tool for those who need precise control or want to understand the underlying data of their mesh. The video suggests that while it's not necessary for beginners, it's an advanced feature that can be beneficial in certain cases.

💡Post Processing

Post processing in the video refers to the steps taken after the initial creation of a mesh to modify or enhance its properties. Geometry Nodes are likened to post-processing for meshes, where the input is the original mesh, and various operations are performed on it to produce an output. This concept is fundamental to understanding how Geometry Nodes work within the Blender workflow.

💡Transform

Transform is a node in Geometry Nodes that allows for the manipulation of geometry through translation, rotation, and scaling. In the script, the Transform node is used to demonstrate how Geometry Nodes can alter the appearance of a mesh without actually changing its underlying data, which is a key concept in non-destructive editing.

💡Distribute Points on Faces

This is a node in Geometry Nodes that scatters points across the surface of a mesh. In the video, it's used to create the effect of sugar crystals on a candy model by distributing points that will later be instanced as smaller cube objects, illustrating how Geometry Nodes can be used to create detailed and realistic textures.

💡Instance on Points

The Instance on Points node is used to replace points with instances of a chosen object. In the tutorial, it's used after points have been distributed on the faces of the cube to create the effect of sugar crystals. This node is essential for turning points, which are invisible in renders, into visible geometry that can be rendered.

💡Random Value

The Random Value node generates random numbers, which is used in the video to create variation in the rotation and scale of the sugar crystal instances. This node is crucial for achieving a natural and random distribution of objects, which is essential for creating realistic effects like the scattering of sugar on candy.

💡Tau (2π)

Tau, or 2π, is a mathematical constant representing the circumference of a circle and is used in the video to set the range for random rotations of the sugar crystals. Understanding Tau is important for creating rotations that span a full 360 degrees, which is more intuitive for artists than working with π.

💡Join Geometry

The Join Geometry node is used to combine multiple geometry inputs into a single output. In the video, it's used to utilize the cube data twice: once for rendering the original cube and once for creating points that will be replaced with instances of the sugar crystal. This node showcases the flexibility of Geometry Nodes in handling complex operations.

Highlights

Geometry nodes allow artists to perform actions based on defined rules, enabling the creation of previously impossible designs or tools for faster production.

Every artist should learn the basics of geometry nodes for core functionality understanding.

The tutorial begins by opening a new scene and accessing the geometry nodes tab.

The spreadsheet, showing exact coordinates of vertices and faces, is introduced but deemed not essential for the tutorial.

Geometry nodes are modifiers that affect the mesh, and their order in the modifier stack matters.

The concept of input and output in geometry nodes is explained, demonstrating post-processing for meshes.

A transform node is used to move, rotate, and scale the cube, showing the difference between node operations and actual mesh changes.

The tutorial aims to create a sugar scattering system on a cube to make it look like a lolly or candy.

The 'Distribute Points on Faces' node is used to scatter points on the cube's surface.

The 'Join Geometry' node is introduced to use the cube data twice within the node setup.

The 'Instance on Points' node replaces points with instances of another object, such as sugar crystals.

A new cube is added as a sugar crystal and scaled down to be used as an instance in the node setup.

The importance of applying the scale of an object in geometry nodes before referencing it is discussed.

The 'Random Value' node is used to generate random rotation values for each sugar crystal instance.

The concept of radians is introduced, explaining the difference between degrees and radians in geometry nodes.

The 'Random Value' node is also used to create random scaling for sugar crystals, but keeping them as cubes.

The tutorial concludes with a preview of the sugar crystal effect on the cube, encouraging viewers to join for the next part.

Transcripts

geometry nodes is like artist-friendly

programming letting you perform actions

based on rules that you define and you

can do some crazy things with it create

things that were previously impossible

or build tools to enable faster

production

every artist should learn the basics

which is what this series is all about

you'll leave with an understanding of

how to use the core functionality of

geometry nodes while making a practical

sugar-coated candy let's begin

so with a brand new scene opened up go

to your geometry nodes tab which is at

the top there and when you do that you

will see a familiar 3d viewport on your

top right and then on the left you've

got this scary looking thing you've

never seen before it's called the

spreadsheet

you won't need to use it basically it's

just showing you the exact coordinates

of like vertices and faces and things

you can see the position of it is

changing as i move that vertically there

useful in a handful of cases but really

we don't need it out of sight out of

mind so i'm just going to right click

join these areas so we don't have to

look at it and now i'm going to click on

new and now we have a geometry nodes

system applied to this cube

you will also note you have a modifier

that has been added here called geometry

notes and that is because geometry nodes

are importantly a modifier

and just like any other modifier the

order of it matters whether i have my

subsurf modifier before it or after it

because it will work top to bottom

and also you could actually add another

geometry node system right underneath it

you could have two so it does this one

first and it does this one after it but

generally you only need one

so

this uh system here is the easiest way

to think of geometry nodes is really

like it is post processing for meshes

okay so we've got our input over here

which is our mesh this cube here and

then it's working left to right and then

it's feeding us an output over here so

whatever i put between those two points

it will do as a post-processing step and

let me demonstrate that you don't have

to follow this this is just for

demonstration i'm going to add in a

transform here and i could move the cube

i could

rotate the cube and i could scale the

cube now that looks like i have changed

the object looks like i've changed the

mesh but actually i haven't if you go

into edit mode you can see that the cube

is still there that hasn't changed that

hasn't moved because that part the mesh

part is what is over here it's only this

part here and then this part here which

is then creating and

it's basically doing that operation and

it's using it here as a modifier if i

disable it in the 3d viewport um you can

see that i've still got my original mesh

there right um so that's that's really

the easiest way to to think of geometry

nodes

but you can do a lot more fancier things

with it than just a simple rotation and

scale and things

like for example um we want to do a a

sugar scattering system on our cube and

the cube is then going to become a lolly

we're going to make it look like a lolly

or a candy if you're american or what

not everything has become american we

just call it candy now anyway um the the

node that we are looking for

by the way shift a if you want to add a

node you can also find it here

uh the note that we're looking for

look you've never heard of it before you

wouldn't know which one to use until

you follow a tutorial and then you see

it and honestly that's the easiest way i

think it that's the best way to learn in

my opinion is to not like look up like

in alphabetical order like what does

each of these things do and when do i

need to use it like just you need to

know it when you need to know it so like

try and do things yourself and then like

look up google it you find a screenshot

or a tutorial and then you learn about

that node that sounded complicated or

weird before so in this case we want to

create

scattered objects so we need points so

underneath points we're looking for

distribute points on faces so when you

click

and if i just you can see as i mouse

over this uh this line here

if i just click do a single click it'll

then automatically join it for me now

joining nodes is if you're familiar with

shaders it's roughly the same thing but

you generally want to have the same

color go into the same color so green to

green purple purple etc there are

exceptions to that and we'll talk about

that later but that's just a general uh

rule so what this has done is it has

taken our mesh data of a cube and it

said okay instead of the mesh you want

to see points and it has now scattered

points on that and you can see if i

increase the density there it looks like

the shape of my cube

okay cool i can do i can do really cool

things with these points i could do

animations i could make them fall i

could do everything but this is just you

know the the most basic form of it now

we actually want to have not just the

points by themselves because if i if i

was to render actually i would get

nothing

because points don't actually render

they're just for the 3d viewport until

you reference them and tell them what to

render them as

i

as well as these points i want to see

the cube so i want to use

the cube data twice and i can do that

with another node that you'll need all

the time which is join geometry shift a

join geometry by the way if you can't

ever remember which which menu it is

under if you just go up to search and

then just type in join or whatever it is

you're looking for you can find it that

way as well so if i drop this in here

after my points on faces you can see

this input here is different it's longer

than these other ones and this is

actually a new concept for geometry

nodes this didn't used to exist but this

will let you put in as many inputs as

you want into this so i can for example

i can take my output of my original cube

data and put it in here which is it's to

me that's pretty cool it's like it's

using the cube data twice it's using it

for rendering the cube and it's also

just taking removing the cube data

replacing it with points and then it's

using that as well and it's combining it

into one which is very cool

so um that's great now again if i was to

render this i wouldn't see those points

because they do not render unless you

tell them what to render as so to do

that we need another node

right after here not before but after it

points we're looking for

points no not points sorry instances

instance on

point not two points completely separate

uh instance on

points someone's honking their horn

right outside all right if i was to drop

this in here you can see the points of

vanish because now it has you're saying

replace those points with whatever is in

the instance right here and we've got

nothing in there right now

so we need another object we need to put

an object into this instance here and we

want them to look like sugar crystals

sugar crystals are basically little

cubes you can by the way you could if

you were fancy you could use cube

whereas mesh primitives you could add in

a cube if you want to but we want to

bevel it later and you know it's just

helpful if it's its own object so i'm

going to in the 3d viewport add another

cube and let's just move this to the

side and i also want to scale it down so

that it's much smaller than this so i'll

just scale this and i'm going to type in

point one so s point one and then enter

and then it will scale it to uh

a tenth of the size okay i have to make

sure i'm like ten to one percent no ten

percent anyways all right also you'll

know by the way if you click on another

object like a camera a lamp or anything

like that the geometry nodes have

vanished and that's because it will by

default it'll only show you what is

selected and it'll also only show you

what's selected in your modifier stack

there if you don't want to have to keep

like searching for your object in order

to see this if you click that pin icon

there then that will pin this here no

matter what is selected this will always

be here until i unpin that so we want to

have that pinned all right so i'm going

to rename this cube here

sugar

crystal

and then i want to reference this in my

geometry node setup down here so i can

do that very simply i love that you can

do this now in blender just click from

my outliner down here

into this node setup and it's now

automatically created an object info

node with that object selected which is

pretty cool all right so i want to

reference this into the instance so you

can probably guess so let's just make

this a little bit bigger

we're going to go green to green

geometry to instance haha

all right now that we've done that um

you can see that it it's doing something

but it's not working the way that we had

hoped and that is because when we added

in this cube and we scaled it down when

you've scaled something down it's not

referencing it in your geometry nodes or

everywhere else in blender perhaps until

you have applied the scale of that so i

did this deliberately just so that you

could see the scale of this is still 0.1

so we need to apply it by hitting

control a and then hit scale and now

those values are one and now it's

referencing it correctly

right so if i was to adjust this uh

density here you can see that i can

choose how many sugar crystals do i want

to appear on my uh my cube it doesn't

look very detailed yet we'll get there

and that value will change it there

which is cool

all right now

it currently looks like i don't know

like a

lazy spaceship you know like how they

used to do like grebel on uh on

spaceships and things for like old

animations and it was just like blocky

shapes um we want this to look like

sugar crystals which are clinging on and

those have to be rotated so each of

these little cubes that we want to be

rotated now there is a rotation value

here in this instance on points but if

we were to change this it's changing all

of the points one by one whereas we want

to create a random value for each of

those points

so for that we need another node that

you will use all the time as well and

that is let's just move this up

shift a

utilities random value again you can

also search for it random if you can

never uh remember what it is random

value

and does what it says on the tin random

value generates a random value between

in this case zero and one

now this is a float a float is a single

number

and that's a gray output a single number

whereas rotation is three it's three

axes x a y and a z so you could actually

connect this into it like that and you

would get rotation but you would see

that you've got kind of like a pattern

right like they're all kind of

rotating almost to the same sort of

thing and it's because like let's say

it's generating a value of like for one

of these points like point two it's

rotating it at exactly

you know

0.2.2.2 or you know whatever like that

for all three of the axes which is not

actually what we want we want each axis

to have its own value independently so

instead of float what i'm looking for is

vector okay so now if i drop this in

here you can see we get a lot more

values

because there's three there's three

there's the min for each of the three

axes x y and z and x y and z for the max

but now that we've got that you can see

that we've got a lot more

uh random rotation happening right

um now the other thing to note is like

okay one is that one degree it looks

like it's more than one degree what is

going on this this value here these are

actually

radians

that's right radians what is a radian a

radian is

57.29

degrees all right it's a mathematical

concept and geometry nodes is generally

mathematical so it's you just have to

get used to it there's like a lot of

math functions and things like that when

it comes to geometry knows

and radians is one of them so this is

not one degree it is one radian which is

about 57 so it is giving us a random

value between 0 and 57-ish degrees if we

set this to 2 it's a little bit more

right it's giving us a little bit more

rotation but again it's not 360. it's

360. it's like you could actually type

in pi

pi would be 180 right because it's uh

3.142 it would be uh yeah it's half of

it but actually we want double pi so if

you wanted to you could type in two

times pi or there's a word for that

which is called

tau

which i didn't know was a word until i

needed it for this exact thing um and

arendelle uh erindale's youtube channel

everyone should subscribe if you want to

go deep into geometry nodes like really

deep um he's the master of it um but tau

towers twice pi it's the full

circumference or whatever of the

circle i should pay attention to math

shouldn't i um anyway

um and just quickly for environments

like if you were say scattering some

photo scan rocks from polygon or you're

building an environment in those cases

you would actually want to rotate on

every on only the z-axis anyways all

right so now let's do these scales so

i'm going to duplicate my random value

here and i'm going to plug this into my

scale

now in the case of scale

uh different to our rotation

we don't want to have um separate values

for our

x y and our z because we might get

something that is not a cube shape right

this looks like they're the same value

but remember each it's generating a

value like in between those right so

you'll get some that are like

rectangular prisms and things so we want

to keep it as a cube but yeah just like

different values of the cube so for that

we want to change it back to float and

then plug that into scale and now they

all stay as cubes but just different

values in there

now i would never have the minimum set

as 0 because then that could technically

be a value which you would not be able

to see but it would still be rendering

so i'm just going to make it just a

little bit more yeah you can see it's

exactly what it's doing there's like a

cube that's like invisible

so yeah i just make it a little bit more

than zero and then it comes through and

there you go and you can see now that

we've got that we've got the sizing that

looks pretty good if we cranked up our

density there you can sort of see what

we're getting at with this tutorial

so we've learned about the basics of

geometry nodes go ahead join me in the

next part as we delve a little more

deeper into some of the idiosyncrasies

so click here on the screen and i'll see

you there