Unreal Engine 4 Tutorial - Splines - Spline Meshes

Unreal Engine 4 Tutorial - Splines - Spline Meshes

Creating Spline Meshes in UE4

Introduction to Spline Meshes

  • The tutorial focuses on creating spline meshes in Unreal Engine 4 (UE4), highlighting their utility for procedural mesh generation within game environments.
  • The presenter demonstrates the creation of a pipe mesh, emphasizing the importance of having multiple segments along its length for accurate bending.

Setting Up the Blueprint Actor

  • To start, a new blueprint class actor named "Pipe Spline" is created. This actor will utilize spline components to define shapes.
  • A spline component is added to the actor; it functions similarly to a pen tool in graphic design software, allowing users to create shapes based on defined points.

Understanding Splines and Construction Scripts

  • The construction script runs whenever changes occur or when the object is spawned, making it essential for procedural content creation.
  • The number of points on the spline is determined using a loop that iterates through each point, which helps manage how many sections are drawn.

Configuring Spline Points and Meshes

  • Adjustments are made to account for how many sections should be represented by subtracting from the total number of spline points.
  • A spline mesh component is added within the loop; this allows for bending along the defined spline path while ensuring proper alignment with specified axes.

Finalizing Mesh Properties

  • Each mesh's forward axis must be set according to its orientation in 3D space, which can be verified by inspecting the mesh's gizmo.

Creating and Modifying a Pipe Spline in Unreal Engine

Setting Up the Pipe Spline

  • The process begins by dragging from the river to set the end position, followed by copying and pasting spline points to connect them to the end position and tangent.
  • After compiling, the pipe spline is visible in the world. Users can manipulate it using control points represented by red dotted lines that adjust its shape.

Adjusting Pipe Shape

  • By holding down the Alt key, additional points can be added to bend the spline as desired. The user can also rotate these points for various shapes.
  • Initially, there is no collision on the pipe; however, collision can be easily added through settings in the pipe spline component.

Addressing Uniformity Issues

  • A problem arises when extending the pipe: endpoints become unevenly stretched. This inconsistency is not realistic for a uniform pipe design.
  • To resolve this issue, a new spline actor is created by duplicating the existing one and renaming it "pipe spline fixed" for later differentiation.

Implementing Section Length Calculation

  • Instead of relying on individual spline points, this method calculates how far along the spline each section should be placed based on total length divided by desired section length.
  • A variable named "section length" is introduced to store default values based on mesh size (e.g., 100 units).

Creating Spline Mesh Components

  • The next step involves calculating how many sections are needed based on total length divided by section length. This allows for consistent placement of mesh components along the spline.
  • Each segment of mesh will now be generated at specific distances along the spline rather than at individual points.

Finalizing Tangent Control

  • The method retrieves locations and tangents at specified distances instead of predefined points. This adjustment ensures more accurate placement of meshes along curves.
  • As pieces spawn correctly along the curve, an issue with tangents stretching remains; further adjustments are necessary to clamp these tangents effectively.

Creating Realistic Pipes with Spline Techniques

Setting Up the Tangent and Section Length

  • The process begins by discussing how to manage tangents in a spline setup. A long spline is dragged out of the vector, and its size is clamped before connecting it to the tangent.
  • The maximum value for this operation will be determined by the section length, which is also connected at the end of the tangent.

Achieving Realism in Pipe Design

  • When spawning elements into the scene, there should be no stretching observed, enhancing realism in pipe appearance. This allows for flexible adjustments to curve points as desired.
  • Scaling operations on the mesh can lead to unexpected results; for instance, making a pipe thicker may cause distortion if not handled correctly.

Adjusting Proportions and Distances

  • To maintain proportionality while scaling pipes, it's essential to adjust distances accordingly. For example, multiplying by 4.5 ensures that dimensions remain consistent.
  • The distance between each pipe segment should be calculated as 100 times 4.5 (resulting in 450), ensuring proper spacing when scaled up.

Final Adjustments and Project Conclusion

  • Additional segments can be added or removed from the pipeline design based on space requirements; removing one segment prevents unnecessary duplication.
  • The video concludes with an invitation for viewer support through platforms like Patreon, emphasizing community engagement and future project development.

Support and Community Engagement

Video description

We continue to look at splines and their many uses in this episode. Spline meshes allow you to procedurally create meshes such as pipes, wires, and roads easily in engine. We look at two types here: ones with a flexible section length, and ones with fixed length sections. Support me on my Patreon and see episodes 2 weeks early: https://www.patreon.com/ryanlaley