DreamMat: High-quality PBR Material Generation with Geometry- and Light-aware Diffusion Models

TL;DR

DreamMat is a novel method that generates high-quality, physically-based rendering (PBR) materials from text descriptions by incorporating geometry and lighting awareness, overcoming limitations of traditional diffusion models.

Contribution

It introduces a light-aware diffusion model fine-tuned for accurate PBR material generation, addressing incorrect material decomposition issues in existing approaches.

Findings

Produces PBR materials with better visual quality

Achieves more accurate material decomposition

Outperforms baseline methods in rendering quality

Abstract

2D diffusion model, which often contains unwanted baked-in shading effects and results in unrealistic rendering effects in the downstream applications. Generating Physically Based Rendering (PBR) materials instead of just RGB textures would be a promising solution. However, directly distilling the PBR material parameters from 2D diffusion models still suffers from incorrect material decomposition, such as baked-in shading effects in albedo. We introduce DreamMat, an innovative approach to resolve the aforementioned problem, to generate high-quality PBR materials from text descriptions. We find out that the main reason for the incorrect material distillation is that large-scale 2D diffusion models are only trained to generate final shading colors, resulting in insufficient constraints on material decomposition during distillation. To tackle this problem, we first finetune a new light-aware 2D diffusion model to condition on a given lighting environment and generate the shading results on this specific lighting condition. Then, by applying the same environment lights in the material distillation, DreamMat can generate high-quality PBR materials that are not only consistent with the given geometry but also free from any baked-in shading effects in albedo. Extensive experiments demonstrate that the materials produced through our methods exhibit greater visual appeal to users and achieve significantly superior rendering quality compared to baseline methods, which are preferable for downstream tasks such as game and film production.