Curl Noise Geometry Filter

This example demonstrates using a geometry filter to deform a 3D mesh in real-time with curl noise.

Overview

A 3D model is loaded and its vertices are displaced each frame by a curl noise function written in GLSL. The deformation intensity is modulated by an LFO through an exponential smoothing filter, creating a fluid, organic animation. The result is textured with a procedural sine warp gradient and rendered through bloom and long exposure post-processing effects.

Key concepts

• Geometry filters: GLSL shaders that modify vertex positions directly on the GPU. They provide a way to deform meshes in real-time without compute shader support.
• Curl noise: A divergence-free 3D noise field derived from simplex noise. It produces smooth, swirling displacements well suited for fluid-like motion.
• Modulation: An LFO drives a Smooth filter that controls the curl noise scale parameter, producing gradual deformation changes.

Data flow

1. Object loader loads the mesh
2. The curl noise Geometry Filter preset displaces vertices based on time and noise parameters
3. A basic shader provides procedural texturing
4. Model display renders the deformed geometry
5. Bloom and long exposure shaders are applied as post-processing

Try it

Open this example to see real-time vertex deformation driven by curl noise.

Download this example

Learn more

• Object loader - Loading 3D models
• ISF Shaders - Interactive Shader Format for GPU effects
• LFO - Low-frequency oscillator for animation
• Model display - 3D mesh rendering process
• Graphics pipeline - How rendering works in ossia score

---