Comparing FPS between instance and merge drawcall and native

Question

I am testing the FPS with my laptop using the Intel(R) Iris(R) Plus Graphics 655 card. To test the threeJS example with Instance rendering and merge-drawcall re

Answer 1

This is only guesses

1. Three.js by default culls if things are outside the frustum.

   We can turn this off with mesh.frustumCulled = false. I didn't notice a difference and this should show up in the draw count.

2. Three.js by default sorts opaque objects back to front.

   This means everything else being equal, sorted will run faster than unsorted because of the depth test. If I set the depth test to always

   material.depthFunc = THREE.AlwaysDepth
   

   Then I seem to get slightly faster rendering with instanced vs native. Of course everything else is not equal.

3. An issue in Chrome.

   If I run in Firefox or Safari I get the expected results. Merged > Instanced > Native

   It could be a bug or it could be they're working around a driver or security issue that the other browsers are not. You'd have to ask.