{ "schemaVersion": "0.11.0", "canonical": "https://www.pystone.net/notes/ue-udim-texture/", "atlas": "https://www.pystone.net/?node=ue-udim-texture#knowledge-atlas", "markdown": "https://www.pystone.net/notes/ue-udim-texture.md", "context": "https://www.pystone.net/notes/ue-udim-texture.context.json", "knowledgeVersion": "224c990773de.5fa8af6e39fa", "build": { "siteCommit": "224c990773de166d23a886306577dd90379529ce", "notesCommit": "5fa8af6e39fa3891d1b9b4832bfa6c4e0ecaaf0a", "builtAt": "1970-01-01T00:00:00.000Z", "version": "224c990773de.5fa8af6e39fa" }, "id": "note:ue-udim-texture", "slug": "ue-udim-texture", "title": "UDIM贴图", "type": "note", "visibility": "public", "idStability": "rename-stable", "author": { "name": "Perrin Yong", "profile": "https://www.pystone.net/profile/" }, "publisher": { "name": "Perrin Yong", "profile": "https://www.pystone.net/profile/" }, "aliases": [], "summary": "UDIM贴图", "contentRole": "unspecified", "isMoc": false, "mocRecognition": "none", "generated": false, "attribution": "unspecified", "domain": "10-计算机、信息技术与工程", "tags": [], "mocs": [], "contentHash": "2cd075a6fd39fff855c3ae935444ad29d2dd2d7e51260aa04c2e01d7e9806c7f", "assets": [ { "reference": "assets/0014 - UDIM贴图__resource-001-171be606884d.png", "url": "/media/a01b8c3b253c6916f6c2.png", "mediaType": "image/png", "contentHash": "a01b8c3b253c6916f6c28f1cb6e03a52ff18337f546e9546b359c6f4fcd8b9a4", "byteLength": 575234, "width": 1404, "height": 761 }, { "reference": "assets/0014 - UDIM贴图__resource-002-a9b2cc5a9f31.png", "url": "/media/3a5a9f10a7832f2cd5b1.png", "mediaType": "image/png", "contentHash": "3a5a9f10a7832f2cd5b1267c50b8b38cc00d8f4e67495e9bf47932a66d6b2bd9", "byteLength": 691701, "width": 1180, "height": 804 }, { "reference": "assets/0014 - UDIM贴图__resource-003-123534db1ace.png", "url": "/media/ef5f2b7f11586429dc58.png", "mediaType": "image/png", "contentHash": "ef5f2b7f11586429dc58dc66c98b14b421254d749ed752a52dc788716fee7cdd", "byteLength": 387163, "width": 1101, "height": 370 } ], "headings": [ { "depth": 1, "text": "UDIM贴图", "anchor": "udim贴图", "citation": "https://www.pystone.net/notes/ue-udim-texture/#udim%E8%B4%B4%E5%9B%BE" } ], "claims": [], "outgoing": [], "incoming": [ { "id": "note:game-graphics-and-runtime", "title": "游戏图形与运行时", "url": "https://www.pystone.net/notes/game-graphics-and-runtime/", "atlas": "https://www.pystone.net/?node=game-graphics-and-runtime#knowledge-atlas", "label": "游戏图形与运行时", "origin": "explicit", "humanReviewed": true, "context": "Unreal中的“UDIM贴图”导航项", "citation": "https://www.pystone.net/notes/game-graphics-and-runtime/#unreal" } ], "contentMarkdown": "# UDIM贴图\n\n# UDIM贴图\n\n> 创建时间：2022/8/23 12:23\n\nU-Dimension (or \"UDIM\") is a texture naming convention that enables multiple texture images to map to separate UV regions on a Static Mesh or Skeletal Mesh model.\n\nUDIM（U-Dimension）是一套多想先贴图映射技术，是目前UV Mapping中比较流行的技术。 是对 UV 贴图和纹理工作流程的增强\n\nUDIM 只是一个自动 UV 偏移系统，它将图像分配到特定的 UV 平铺上，它允许您对相邻表面使用多个较低分辨率的纹理贴图，从而产生更高分辨率的结果，而不必求助于使用单个、超高分辨率图像。\n\nUV 映射是将三维表面转换为平面位图图像的二维坐标系. 原始表面的每个顶点在 UV 贴图上都有一个坐标，中间的像素值在平坦的多边形表面上进行插值，以实现高度精确的纹理控制。UV贴图坐标值被组织到一个网格系统中，其中图像本身出现在网格的0-1区域中，而此图块外部的区域仅向外重复图像。因此，传统上实际上只使用过UV 0-1空间（好在控制表面如何平铺图像的方式之外）。\n\n使用 UDIM 工作流，每个完整的切片部分（0-1、1-2、2-3 等）都可以分配给它自己的独立图像映射，所有这些都在同一表面内。每个图像也可以有自己的分辨率。\n\n普通的UV是在其他象限图像都不断重复的UDIM，UDIM是每个象限图像都不同的UV。\n\nMaya操作：\n\n材质 - 贴图 -UVTilingMode:UDIM\n\n把1001贴图选中，会自动识别UDIM贴图序列。\n\n引擎实现：\n\n编辑 - 项目设置 - 渲染 - 启用虚拟纹理支持，重启UE。 会编译Shader（空工程要等41分钟）\n\n选择UDIM的第一张导入UE Editor，就会自动生成VT\n\n纹理赋值给基础颜色\n\nShader实现原理：能根据U的值确定使用哪张纹理，也能根据V的值决定使用哪张纹理，那么，完成逻辑：分别根据U和V的范围，决定使用哪张纹理即可。\n\n![](assets/0014 - UDIM贴图__resource-001-171be606884d.png)\n\n![](assets/0014 - UDIM贴图__resource-002-a9b2cc5a9f31.png)\n\n![](assets/0014 - UDIM贴图__resource-003-123534db1ace.png)\n\n可以把一大段材质的逻辑打包成材质函数。\n\nUDIM贴图：组成的贴图数量太多的情况下，双击打开时，可能会挂掉\n\n相关资源：\n\n\n" }