Houdini 19.5, UE5 - Procedural Stylized Pencil Case(s) + RBD

Name: Houdini 19.5, UE5 - Procedural Stylized Pencil Case(s) + RBD
Rating: 4.2 (2 reviews)

In this project-based Houdini & UE5 course we'll create 4 HDAs and go over common procedural modeling approaches.

Created byDmitriy Zub

Last updated 8/2023

English

English [Auto],

What you'll learn

Better understand procedural modeling in Houdini with provided examples.
Increase understanding of Houdini.
Houdini's For Each Loop.
How to randomize shape, colors, etc.
How to create Houdini Digital Asset specifically for Unreal Engine 5.
How to add Rigid Body Simulation to pencils per case.
How to create Unreal Engine 5 specific attributes (Nanite, LOD screen size).
How to create Unreal Engine 5 collision and LODs groups.
How to add vertex colors to procedural model(s).
How to create procedural pencil.
How to scatter pencils within pencil case.
How to create procedural pencil case.
How to scatter pencil cases within area bounds and randomize each case/pencil.

Course content

3 sections • 68 lectures • 4h 15m total length

Creating base shape1:24
Create a base pencil in Houdini 19.5 UE5 by turning a circle into a polygon, orient on the z plane, reverse normals, and extrude with a distance parameter.
Creating wood and tip3:02
Closing bottom hole, modifying base shape0:42
Explore closing bottom holes and modifying base shapes while shaping a pencil via extrusion, adjusting circle divisions, and refining parameters for a clean pencil look.
Creating groups4:15
Here we will be creating groups that will be used down stream in the node graph, especially in the coloring phase.
Adding shaving effect4:41
Resample node is used to create more points on the surface which is needed for the Mountain node to distort its shape.

In other words, the more points will be, the more points will the Mountain node have to distort (create different shapes).

With 6 points, it's not possible. Try to turn off resample node and see the difference after the Boolean node.
Polishing shaving effect2:34
Polish the shaving effect by isolating the bottom face, refining geometry with subdivide and surface adjustments, tweaking the crisp white attribute, and reprojecting with distance controls before grouping base.
Finishing tip3:44
Adding bottom circle (pencil lead part)1:55
Create the bottom circle as a primitive in the xy plane, increase divisions to 24–32, use a geometry bounding box with parameter reference and relative reference, set offset, then merge.
Fixing bottom circle open hole1:30
Polish base shape (get rid of harsh edges)2:08
Apply tweaks to amount, scale, and ratio to soften harsh edges, then subdivide and increase division size to add edge loops for a smoother base shape.
Organizing node graph1:33
Adding vertex color3:12
Rigid Body: preparation1:13
Rigid Body preparation: making pencil as a single mesh7:12
Creating Rigid Body Simulation5:52
Create a rigid body simulation by pairing a pencil with a collider using an object merge node, then export frames with a timeshift node and tune collision patterns.
Rigid body: dynamically place pencil on top of any input geometry3:38
Demonstrates dynamic rigid-body pencil placement on top of any input geometry using mesh size and y-axis justification, updating the bounding box as shapes merge and simulation runs.
Finalize: creating normals1:19
Finalize normals by creating three normal groups—base, tip, and wood—set the angle to 52, and mark the bottom circle as a primitive to avoid Unreal normal issues.
Finalize: additional cleaning0:38
Finalize the procedural stylized pencil case workflow by cleaning attributes and groups in Houdini 19.5, removing degenerate primitives, and preserving only color and normal.
Finalize: creating collision group0:18
Finalize: creating Nanite attribute0:44
Create a Nanite attribute named enable the night and use a switch node to toggle night mode, set default 0 or 1 with integer type, and experiment with presets.
Finalize: creating LODs2:10
Create four LOD groups from highest to lowest, naming them after the node. Apply poly reduce: 10% for the lowest, 20% for the next, and 50–65% for the rest.
Finalize: creating LOD Screen Size3:16
Create and configure a log screen size attribute with attribute create, assign presets, and apply screen size to log zero, defining 1 as highest load and 0 as lowest.
Finalize: organize graph1:04
Finalize the scene by cleaning up items, preparing geometry for the simulation, and coloring it pink, then create an interface and test it inside Unreal Engine before creating HDR.
HDA: Creating HDA0:14
Select the completed model and convert it into an HDA by creating a subnet, either via the subnet icon or using the Shift C shortcut.
HDA: creating shape parameters8:31
Add tweakable radius with min/max ranges and lockable defaults in Houdini 19.5. Use collapsible shading folders and set screen size and polygons to keep for preview.
HDA: controlling parameter(s) visibility with "hide when" parameter option2:29
Master Houdini 19.5 hda parameter visibility by using a toggle and the hide when option to hide folders when off, with default value 1 and 0 disables.
HDA: creating color parameters1:47
Create a collapsible folder named coloring to hide and show parameters. Copy the toggle parameter into switch node as a relative reference, then set the base color and ink color.
HDA: creating nanite parameter0:36
Copy, paste, and save daily while enabling logs and night attribute; then manage four group log groups and detail attributes for screen size to create the nanite parameter in hda.
HDA: adding simulation parameters5:39
Learn to set up Houdini HDA simulation parameters for a stylized pencil case, including collision objects, wind, timescale, substeps, toggle switches, reset controls, and testing.
Unreal Engine: creating project0:58
Unreal Engine: testing HDA4:17
Test Houdini digital assets in Unreal Engine 5 by dragging into scene, enabling simulation, and configuring collision objects in the world outliner to observe realistic rigid-body collisions.
Unreal Engine: enabling Nanite and LODs3:25
Learn to enable nanite and manage LODs in Unreal Engine by adjusting static mesh settings, toggling render collision geometry, rebuilding assets, and exploring load size options.
End of the Section0:12
Conclude this section by reviewing the pencil model, parameter creation, and simulation tests. Preview how it looks inside Unreal Engine.

Creating Pencil Case Part 12:49
Creating Pencil Case Part 24:45
Close bottom holes with polyfill, select faces by normals, and add thickness using point extrude in pencil case part 2, then refine edges with poly bubble to complete the case.
Adding Vertex Colors, Unreal Attributes, Collision Group, Low Poly11:42
Design a procedural stylized pencil case in Houdini 19.5 for UE5, adding vertex colors, unreal attributes, a collision group, and a low poly option.
Creating Case HDA0:41
Create a Houdini case HDA by highlighting the subnet, naming it Udemy Pencil Case, using the Digital Asset Create New option, selecting the branch, and applying the use this options setting.
Case HDA - part 117:19
In Houdini 19.5, build a procedural pencil case from a line sweep, add edge loops, close holes with polyfill, and apply Unreal material attributes for a reusable asset.
Case HDA - creating parameters - part 21:15
Enable and disable parameters in the case hda by right-clicking a parameter, using channel references and the switch node to set values (1 on, 0 off) for materials and colors.
Case HDA - creating parameters - part 3 (controlling UI with toggles)4:54
Master how to use toggles in houdini hda to enable or disable parameters and nodes, hide unused controls, and drive materials and colors via channel references.
Preparation for scattering pencils within the case bounds6:36
Creating For Each Loop with For Each Metadata node0:22
Create a for each loop for each point, ensure a metadata node in the begin block, and use the metadata node to access the iteration number during the loop.
Copying (scattering) pencils inside case shape1:59
Procedurally generate and scatter pencils inside the case shape, copying to points and adjusting placement, height, scale, and case length for the desired stylized look.
Creating randomization controller (Null node)3:49
Create a null as a randomization controller in Houdini to mix radius, height, shaping, and color parameters, then expose these controls via a parameter interface for efficient randomization and optimization.
Randomizing pencils/case colors/etc16:47
Master per-pencil randomization in houdini by driving offsets, sizes, radii, and height with iteration-based seeds. Also learn to randomize pencil colors using per-channel rgb seeds for base and top colors.
Adding RBD and fixing attributes mismatch on Merge9:25
Master Houdini 19.5 RBD simulations for a pencil case in UE5, using RPD bullet solver, collision inputs, and merges, with performance switches and attribute fixes for normals and vertex colors.
Sped up RBD simulation0:36
Clean up, normals and collision group2:15
clean up geometry, remove degenerate primitives, preserve a group via wildcard, set collision group rendered collision, add nodes, configure python group with relative reference, and set pencils to ten degrees.
Creating group LODs and lodx_screensize attributes2:52
Organizing node graph0:48
Organize the node graph and establish parameters to drive procedural stylized pencil cases, emphasizing clear organization and deliberate randomization in the workflow.
Pencil case HDA - creating parameters - part 16:36
Pencil case HDA - creating parameters and testing - part 29:01
Testing Pencil Case HDA in Unreal Engine 5 and creating two variations3:46

Preparation: creating scatter area bounds2:15
Creating For Each Loop1:23
Implement a for each loop workflow in Houdini to generate three pencil case instances by using an import metadata node, accessing the iteration, and copying to points with optional coloring.
Creating Debug Plane2:32
Add a debug plane to visualize scattering area; drive its visibility with a switch node and a null reference, then merge after the for-each loop and toggle via hdr level.
Creating randomization controller (Null node)4:53
Create a randomization controller (null node) to drive pencil cases and pencils in Houdini 19.5, organizing simulation and color parameters to randomize the output frame number via time shift mode.
For each loop: randomizing pencils (shape, shaving, etc.)8:01
For each loop: randomizing case shape (height, radius)2:05
Use a for-each loop to randomize the case height and radius with a seed and adjustable min-max values for a stylized pencil case.
For each loop: randomizing case channel ramp shape5:05
For each loop: randomizing colors (pencils and cases)2:32
Use Houdini 19.5 and UE5 to procedurally color pencil cases and pencils, introducing random color variation via an expression and RGB channel controls (R, G, B).
Creating Rigid Body simulation2:58
Isolate pencils from cases to simulate pencil drops only, using a group, bullet solver, concave collision, and cartesian geometry for RPG creation.
RBD: troubleshooting (when object passing through geometry)3:15
Fix pencils passing through geometry by adjusting the pencil case generator settings—expand 2d, pencil radius, and transform multiply—and test with a reset simulation to ensure proper collision inside the shape.
Cleaning attributes, etc0:54
Clean all attributes and abnormals, enable open source, remove all groups by accepting group underscore, keep the default case, and add an output node.
Creating LODs1:52
Create lods by using a switch node to enable or disable a log group, set screen sizes, apply polygon reductions (70%, 40%, 20%, 10%), and test in Unreal Engine.
Creating HDA parameters18:52
Create and organize Houdini digital asset parameters for a stylized pencil case in UE5, using toggles, folders, and randomization. Manage collision settings, pencils, and color for testing inside Unreal Engine.
Testing inside Unreal Engine3:45
Test inside Unreal Engine by importing pencil cases and pencils, adjusting scale and height with a transform node before output, and experimenting with color, simulation, and radius parameters.
Creating a scene for renders (timelapse)0:30

Requirements

A basic knowledge of Houdini interface.
A basic understanding of Houdini channel (parameter) reference.
A basic understanding of what attributes in Houdini is.
A basic understanding of Houdini For Each Loops (nothing crazy).
Created at least few basic Houdini models (procedural or in traditional way). Optional.
A basic knowledge of Unreal Engine 5.
Unreal Engine 5 and Houdini Engine plugin installed.

Description

Grateful for you taking a look.

To adjust your expectations, I won't be sharing source files (HDA and HIP). This is done on purpose so you can practice and get a better feel using Houdini.

My personal mission is to do my best to help people actually get a feel of Houdini and use its power. There's no shortcut to understand something without practice.

The course is fully narrated. The only very last video is a timelapse.

Houdini is all about efficiency. You create a tool once, use it on multiple projects, and polish it to suit different tasks.

Even though the final models look simple, this course covers some common procedural modeling approaches such as randomization, for each loops, and other faced things when making procedural models. Understanding similar techniques will help to approach any other model that you need to create.

This course starts from the upper beginner level and "climbs" to the intermediate-advanced level. The course is split into small parts so it doesn't feel overwhelming.

This course is aimed to:
- provide examples that might be used in a real-world scenario rather than creating an abstract model.
- increase your understanding of Houdini and how certain things work.
- increase your understanding of uses cases of Houdini Engine for Unreal Engine 5.

This is a project-based course where we'll create 4 Houdini Digital Assets (HDA) that you can reuse in different projects:

1. Pencil HDA.
2. Case HDA.
3. Case + Pencil HDA (scatter pencils within the case).

4. Scatter cases with pencils within area bounds HDA.

All HDAs expect "Case HDA" will have support for Rigid Body Simulation, in other words, pencils will interact with collision geometry. I've created this model for my own environment project and thus decided to share my approach to creating it.

The course has 3 sections:

1. Pencil HDA creation + RBD.
2. Pencil case HDA + scattering pencil HDA within that case and randomizing pencils + RBD.
3. Scatter pencil cases, randomizing cases/pencils RBD.

Some of the lectures contain additional description with the information I missed explaining. Such as what's the purpose of certain node(s).

Who this course is for:

Environment artists who want to speed up/automate their workflow.
Indie developers.
3D modelers from other software (Blender, C4D, 3DS Max, Maya, Modo).
Beginner Houdini users.

Houdini 19.5, UE5 - Procedural Stylized Pencil Case(s) + RBD

What you'll learn

Explore related topics

Course content

Creating procedural pencil with RBD support33 lectures • 1hr 26min

Creating pencil case and adding RBD simulation to pencils20 lectures • 1hr 48min

Scattering pencils cases with pencils RBD simulation15 lectures • 1hr 1min

Requirements

Description

Who this course is for: