Traditional CPU particle systems iterate through arrays of JavaScript objects to update velocities and positions, hitting performance walls at roughly 5,000 particles. WebGL 2.0 Transform Feedback executes particle physics entirely inside vertex shaders on the GPU, updating and rendering over 200,000 particles simultaneously without CPU bottlenecking.
1. Transform Feedback Pipeline Stages
| Stage | GPU Buffer Role | Shader Action |
|---|---|---|
| 1. Read State (VBO A) | Current positions, velocities, and lifetimes. | Vertex shader computes gravity, wind, and drag forces. |
| 2. Transform Feedback | Writes updated attributes into VBO B without fragment stage. | GPU streaming writes directly to video memory. |
| 3. Render Pass | Instanced draw call renders quads from VBO B. | Fragment shader applies texture and additive blending. |
| 4. Buffer Swap | Swaps VBO A and VBO B (Ping-Pong pattern). | Prepares buffer for the subsequent frame tick. |
