Missing, correct and doubled OutputPass
Pixel values are rounded to steps of 5. The last line is the washed-out look.
Post-processing draws the scene into a picture, then changes the picture with a chain of passes. On WebGL that is EffectComposer, and the chain must end with OutputPass once. On WebGPU a node pipeline does the same.
Change the code and press Run (Ctrl+Enter). Predict what will happen first, then break it on purpose and read what changes. Your edits are saved and match the lesson page.
Ready for more? This phase has 4 hands-on exercises with automatic checks.
Practice questions
Write the code in the editor, run it, then open the model answer to compare.
List the passes, in order, for a chain with an outline, bloom and FXAA.
Write a function createChain(renderer, scene, camera) that returns a plain renderer call when the GPU cannot draw into half-float targets.
Explain it without notes
Why must OutputPass come before FXAA, and why only once?
A teammate adds bloom to a page and the colours look washed out. List three things to check.
Console
Nothing logged yet.Expected console output
renderer.render (direct) orange: 255, 105, 45 grey: 130, 130, 130
Render + FXAA (no OutputPass) orange: 255, 35, 5 grey: 55, 55, 55
Render + Output + FXAA orange: 255, 105, 45 grey: 130, 130, 130
Render + Output + Output + FXAA orange: 255, 175, 115 grey: 190, 190, 190