How to Enable POM and PBR in Optimum Realism (Iris/OptiFine Setup)

Pick the right shader pipeline

Optimum Realism ships POM (parallax occlusion mapping) and PBR (physically based rendering) data as separate texture maps, but nothing renders unless your shader loader is configured to read them. With Iris, open the shader selection screen and choose a shader that explicitly supports PBR and parallax — LabPBR-compatible packs are the safe bet. With OptiFine, go to Video Settings > Shaders and select a shader with the same support, then open its shader options.

Turn on the maps

Inside the shader options, look for toggles named Parallax, POM, Parallax Occlusion, or Depth. Enable them. Then find the PBR section and enable Normal Map, Specular Map, and Roughness (some shaders bundle these under one 'PBR' switch). Set Parallax Depth or Height to a low value first — high values cause visible warping on flat surfaces like planks and stone.

Verify it is working

Place a stone block, an anvil, and a bookshelf side by side. With POM active, the anvil's surface should show real depth when you move your camera, and the bookshelf spines should shift. If everything looks flat, your shader lacks PBR support — swap shaders rather than fiddling with resource pack order. Resource pack order does not affect POM/PBR; only the shader does.