# 贴图来源

本目录的 PBR 贴图均来自 CC0（公共领域）素材库，可自由使用、修改、商用，无需署名；这里仍逐一列出出处。
文件命名：`<id>_diffuse.jpg`（颜色）、`<id>_nor_gl.jpg`（OpenGL 法线）、`<id>_arm.jpg`（R = AO，G = 粗糙度，B = 金属度）。
处理：统一缩到 1K 或 512，JPG 质量 82；个别做了旋转 / 调色 / 合成（见“处理”一栏）。

## 建筑外墙与构件

| 文件 id | 素材 | 来源 | 许可 | 处理 |
|---|---|---|---|---|
| tiles136a | Tiles 136 A | https://ambientcg.com/a/Tiles136A | CC0 | AO + Roughness 打包成 ARM；法线 / ARM 1K / 512 |
| long_white_tiles_h | Long White Tiles | https://polyhaven.com/a/long_white_tiles | CC0 | 旋转 90° 成横排条砖（法线通道同步旋转） |
| rounded_square_tiled_wall | Rounded Square Tiled Wall | https://polyhaven.com/a/rounded_square_tiled_wall | CC0 | ARM 缩到 512 |
| square_tiled_wall | Square Tiled Wall | https://polyhaven.com/a/square_tiled_wall | CC0 | ARM 缩到 512；颜色图压平大尺度色带、对比度适度降低（远看不起条纹） |
| rectangular_facade_tiles_02 | Rectangular Facade Tiles 02 | https://polyhaven.com/a/rectangular_facade_tiles_02 | CC0 | ARM 缩到 512；颜色图压平大尺度色带、对比度降到约 0.55（远看不起条纹） |
| red_brick | Red Brick | https://polyhaven.com/a/red_brick | CC0 | ARM 缩到 512 |
| brick_wall_08 | Brick Wall 08 | https://polyhaven.com/a/brick_wall_08 | CC0 | ARM 缩到 512 |
| brick_wall_006 | Brick Wall 006 | https://polyhaven.com/a/brick_wall_006 | CC0 | — |
| painted_plaster_wall | Painted Plaster Wall | https://polyhaven.com/a/painted_plaster_wall | CC0 | — |
| concrete_wall_003 | Concrete Wall 003 | https://polyhaven.com/a/concrete_wall_003 | CC0 | 降饱和度、压低对比、提亮（便于着色）；法线 / ARM 512 |
| damaged_plaster | Damaged Plaster | https://polyhaven.com/a/damaged_plaster | CC0 | 512 / ARM 256 |
| concrete_layers_02 | Concrete Layers 02 | https://polyhaven.com/a/concrete_layers_02 | CC0 | 降饱和度；ARM 512 |
| granite_tile_03 | Granite Tile 03 | https://polyhaven.com/a/granite_tile_03 | CC0 | 512 / ARM 256 |
| corrugated_iron_02 | Corrugated Iron 02 | https://polyhaven.com/a/corrugated_iron_02 | CC0 | 去色提亮（便于着成蓝色 / 白灰彩钢板）；512 |
| painted_metal_shutter | Painted Metal Shutter | https://polyhaven.com/a/painted_metal_shutter | CC0 | 512 / ARM 256 |
| rusty_metal_02 | Rusty Metal 02 | https://polyhaven.com/a/rusty_metal_02 | CC0 | 512 / ARM 256 |
| roof_flat_mix | Concrete Layers 02 + Bitumen | https://polyhaven.com/a/concrete_layers_02 ， https://polyhaven.com/a/bitumen | CC0 | 两套贴图按无缝周期噪声遮罩合成（水泥屋面上补的沥青卷材）；512 |
| grey_roof_tiles | Grey Roof Tiles | https://polyhaven.com/a/grey_roof_tiles | CC0 | — |
| weathered_plank_siding | Weathered Plank Siding | https://polyhaven.com/a/weathered_plank_siding | CC0 | — |

## 断面与碎块

| 文件 id | 素材 | 来源 | 许可 | 处理 |
|---|---|---|---|---|
| hacked_concrete | Hacked Concrete | https://polyhaven.com/a/hacked_concrete | CC0 | 512 / ARM 256 |
| broken_brick_wall | Broken Brick Wall | https://polyhaven.com/a/broken_brick_wall | CC0 | 512 / ARM 256 |
| concrete_debris | Concrete Debris | https://polyhaven.com/a/concrete_debris | CC0 | — |

## 地面与地形

| 文件 id | 素材 | 来源 | 许可 |
|---|---|---|---|
| asphalt_02 | Asphalt 02 | https://polyhaven.com/a/asphalt_02 | CC0 |
| concrete_pavement | Concrete Pavement | https://polyhaven.com/a/concrete_pavement | CC0 |
| sparse_grass | Sparse Grass | https://polyhaven.com/a/sparse_grass | CC0 |
| aerial_grass_rock | Aerial Grass Rock | https://polyhaven.com/a/aerial_grass_rock | CC0 |
| rock_face | Rock Face | https://polyhaven.com/a/rock_face | CC0 |
| dry_ground_rocks | Dry Ground Rocks | https://polyhaven.com/a/dry_ground_rocks | CC0 |

## 其他

| 文件 | 说明 |
|---|---|
| waternormals.jpg | 水面法线贴图，早于本记录加入，出处未核实（常见于 three.js 示例，three.js 为 MIT 许可） |