Performance & Optimizations¶
World Bending Shaders has been rigorously tested in both the editor and packaged builds to ensure reliable performance. Delivering stability is a top priority, and numerous optimizations have been applied throughout development to achieve optimal results. In this section, we’ll explore common issues along with their solutions, and also highlight some limitations of the asset pack.
Mesh Bounds¶
The first—and likely most common—issue you may encounter is meshes disappearing. This typically occurs when deformation pushes the mesh outside its original bounds, causing it to be culled. The fix is straightforward: increase the Bounds Scale in the Details panel. However, use this setting with care—setting it too high can negatively impact performance.
a. Hut in the back is culled
b. Hut with higher Bounds Scale
Max World Position Offset Displacement¶
Sometimes, increasing the Bounds Scale won’t affect the culling behavior. In these cases, you’ll need to raise the Max World Position Offset Displacement value in the Material’s Details panel. This will cause the mesh to clip beyond a certain point, and unfortunately, there’s no current workaround for this. To manage the clipping, you’ll have to get creative with hiding it. Also, if lowering the Bounds Scale doesn’t impact how the mesh deforms, keep it reduced to help preserve GPU performance as much as possible.
a. Max WPO Displacement = 0 | b. Max WPO Displacement = 7500
Nanite Holes¶
When using Nanite with certain shaders, you might notice holes appearing in the meshes. This issue is once again related to mesh bounds. In most cases, increasing the Max World Position Offset Displacement value will resolve the problem.
Nanite Holes when Max WPO Displacement is low.
Max WPO Displacement = 5000.
Note
If your mesh uses multiple materials, you don't need to set the Max WPO Displacement value in every one of them. Setting it in just a single material is usually sufficient.
Optimizations¶
Setting Max WPO Displacement too high can negatively impact performance. In shaders with strong Z-positive deformations—like MF_Runner—you might be tempted to increase the value to avoid clipping. But rather than applying a high value across the board, it’s better to split the mesh and assign a larger displacement only to the parts that actually deform upwards. This keeps unnecessary calculations to a minimum.
For example, in the Inception Town scene, only the upward-bending chunks use a high Max WPO Displacement, helping maintain performance.
Nanite Performance¶
It’s important to understand that Nanite doesn’t perform well with high Max World Position Offset Displacement values. The larger this value gets, the less effective Nanite becomes—and if it’s too high, it can actually result in worse performance than having Nanite disabled altogether.
Knowing when to use Nanite versus traditional LODs is key. The Infinite Racer example level is a good demonstration of this. At first, I enabled Nanite on all meshes, but performance took a hit because the Max WPO Displacement was too high. After switching to traditional LODs and disabling Nanite, performance improved significantly.
Packaged Infinite Racer using Nvidia Stats
Nanite Oversimplification¶
In Unreal Engine versions 5.4 and above, Nanite can sometimes over-simplify meshes, leading to unwanted "low poly" artifacts in certain shaders. For example, in the image below, you can see how the floor texture becomes warped near the end of the hallway, and the mesh edges start appearing noticeably sharper.
To fix this, go to your mesh settings, in the Nanite section increase the Max Edge Length Factor to something appropriate, in this case 100.
Once the settings are applied, the same hallway becomes much smoother.
Here's another comparison, side by side. Image A shows significant over-simplification at the end, Image B shows desired effect.
Note
The Max Edge Length Factor setting is available only in Unreal Engine 5.4 and later. Earlier versions did not show this over-simplification behavior during testing.
Instanced Static Meshes¶
Instanced Static Meshes (ISMCs) tend to perform poorly with materials that use World Position Offset (WPO). I tested this asset using 1000 instances of a 250k triangle mesh (totaling 2.5 million triangles), and the performance dropped significantly as soon as WPO was applied. This isn’t a flaw specific to this asset pack—it's a known issue with how the ISMC rendering pipeline handles WPO.
The easiest fix is to enable Nanite, which can greatly boost performance. Just be sure to keep in mind the Nanite limitations we discussed earlier.
500 Instances @250k tris (No Nanite)
500 Instances @250k tris (Nanite)
Particle Pivot¶
If you want certain shaders like MF_Balloon to use the instance’s own local pivot instead of a global or fixed one, just connect the Mesh Particle Pivot Location node to the shader’s Pivot input. This allows the deformation to originate from each instance’s center.
Individual Balloon Inflation
Particle Axis¶
For shaders like MF_TheScream, you might want the effect to align with the local direction each instance is facing. To achieve this, open MF_WaveFunction (found in WorldBendingToolkit/MaterialFunctions/TheScreamFunctions) and transform the input Position from World Space into Instance & Particle Space. This ensures the wave deformation respects the orientation of each instance.
(L) Global Axis, (R) Local Axis. Arrows indicate direction of wave.
Translucent and Other Materials¶
WPOs operate on the mesh itself, not the material type. This means you can apply vertex deformation to any mesh, regardless of the material it's using. For instance, in the Tiny Planet example, I applied WPO to a Single Layer Water Material without issue.
Simple water material using MF_TinyPlanet WPO
Render Velocities¶
Transparent materials give us a valuable chance to optimize performance by disabling Render Velocities. If your material has Output Velocity enabled, consider turning it off in the material’s detail panel. Velocity rendering is mainly used for effects like motion blur and temporal anti-aliasing, but it can be costly on the GPU. If your material doesn’t need it, disabling it can improve performance.
Dynamic Shadows¶
Another way to optimize performance is by disabling Dynamic Shadows, especially in large environments like terrains or landscapes. However, only consider this if you're okay with sacrificing some visual quality.
Landscapes¶
Landscapes can be a tricky subject with this asset. I’ve thoroughly tested each shader on landscapes and found that while WPO effects generally work fine, issues arise with normal compatibility. As discussed in the previous chapter, without dynamic normals, the landscape’s appearance can break down—especially with heavy deformations.
Additionally, optimizing performance on landscapes can be difficult and unpredictable. Because of that, I recommend importing your terrain as a separate mesh if you plan to use WPOs extensively. Still, you're encouraged to experiment and see what works for your setup!
Note
Make sure to increase Positive Bounds Extension or Negative Bounds Extension via details panel depending on your shader. This reduces flickering and clipping.
