使用Vuforia、ARCore与Unity时模型无法受光问题求助

Hey there! Let's figure out why your knight model is staying dark while the tree asset works perfectly. Since the tree renders correctly with your current lighting setup, the issue is definitely tied to the knight model's own settings or import configuration. Here are the most common fixes to check step by step:

1. Audit the Model's Material & Shader #

• First off, check what shader the knight's material is using. If it's an Unlit Shader or a custom shader that doesn't support real-time lighting, that's almost certainly the problem. Swap it out for the same shader your tree uses (like Unity's built-in Standard shader) and see if it brightens up.
• Double-check the material's Albedo color—if it's set to a near-black value, even proper lighting won't make it look bright. Also ensure the alpha/transparency slider isn't cranked down accidentally.
• Verify that Receive Shadows and Cast Shadows are enabled in the material settings. While disabled shadows might not make it fully dark, it can contribute to a flat, unlit look.

2. Check Mesh, UVs, and Normals #

• UV mapping issues can break lighting calculations. If the knight's UVs are unassigned, overlapping, or stretched, the shader can't properly sample light data. Select the knight model, go to the Mesh Renderer component, and look for any warnings about UV problems in the Inspector.
• Inverted normals are a classic culprit. If the model's normals are pointing inward, only the "inside" of the mesh will receive light, making the outside appear dark. You can fix this by:
  • Adding a Normal Recalculation component to the knight in Unity, or
  • Re-exporting the model from your 3D software with correct normals enabled.

3. Fix Import Settings #

• Select the knight model in your Project window, open the Import Settings panel, and head to the Model tab:
  • Set Normals to Calculate (instead of None or Import) to let Unity generate proper lighting normals for the mesh.
  • Jump to the Materials tab—if it's set to Do not import materials, the model might be using a default, unlit material. Switch it to Import materials or manually assign a working material from your tree asset.

4. Verify Layer & Scene Setup #

• Make sure the knight is on the same layer as the tree. Some custom layers might be excluded from real-time lighting calculations. Check the layer dropdown in the top-right of the Inspector when the knight is selected.
• Rule out accidental occlusion: Is there an invisible collider, AR tracker object, or other mesh blocking light from reaching the knight? Toggle the visibility of other objects in the scene to test this.

5. Check Vuforia/ARCore Lighting Integration #

• Even though the tree works, confirm that ARCore Light Estimation is playing nice with the knight's material. Light Estimation adjusts scene lighting to match the real environment—if the knight's shader doesn't support dynamic light adjustments, it might stay dark. Try temporarily disabling Light Estimation in your ARCore session settings to see if that fixes it.
• Quick check: Ensure your Vuforia Image Target doesn't have any special lighting overrides enabled (like disabling light influence for tracked objects). This is less likely since the tree works, but it's worth a quick glance.

If none of these steps work, try re-exporting the knight model as a clean FBX from your 3D software (making sure to include materials and correct normals) and re-import it into Unity. That often resolves hidden import glitches.

内容的提问来源于stack exchange，提问作者bluiska