Textures.html 21 KB

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  1. <!DOCTYPE html>
  2. <html lang="zh">
  3. <head>
  4. <meta charset="utf-8" />
  5. <base href="../../../" />
  6. <script src="page.js"></script>
  7. <link type="text/css" rel="stylesheet" href="page.css" />
  8. </head>
  9. <body>
  10. <h1>纹理常量(Texture Constants)</h1>
  11. <h2>映射模式</h2>
  12. <code>
  13. THREE.UVMapping
  14. THREE.CubeReflectionMapping
  15. THREE.CubeRefractionMapping
  16. THREE.EquirectangularReflectionMapping
  17. THREE.EquirectangularRefractionMapping
  18. THREE.CubeUVReflectionMapping
  19. THREE.CubeUVRefractionMapping
  20. </code>
  21. <p>
  22. 这些常量定义了纹理贴图的映射模式。<br />
  23. [page:Constant UVMapping]是默认值,纹理使用网格的坐标来进行映射。<br /><br />
  24. 其它的值定义了环境映射的类型。<br /><br />
  25. [page:Constant CubeReflectionMapping] 和 [page:Constant CubeRefractionMapping] 用于 [page:CubeTexture CubeTexture] ——
  26. 由6个纹理组合而成,每个纹理都是立方体的一个面。
  27. 对于[page:CubeTexture CubeTexture]来说,[page:Constant CubeReflectionMapping]是其默认值。<br /><br />
  28. [page:Constant EquirectangularReflectionMapping] 和 [page:Constant EquirectangularRefractionMapping]
  29. 用于等距圆柱投影的环境贴图,也被叫做经纬线映射贴图。等距圆柱投影贴图表示沿着其水平中线360°的视角,以及沿着其垂直轴向180°的视角。贴图顶部和底部的边缘分别对应于它所映射的球体的北极和南极。
  30. <br /><br />
  31. 请查看示例:[example:webgl_materials_envmaps materials / envmaps] 。
  32. </p>
  33. <h2>包裹模式</h2>
  34. <code>
  35. THREE.RepeatWrapping
  36. THREE.ClampToEdgeWrapping
  37. THREE.MirroredRepeatWrapping
  38. </code>
  39. <p>
  40. 这些常量定义了纹理贴图的 [page:Texture.wrapS wrapS] 和 [page:Texture.wrapT wrapT] 属性,定义了水平和垂直方向上纹理的包裹方式。
  41. <br /><br />
  42. 使用[page:constant RepeatWrapping],纹理将简单地重复到无穷大。
  43. With [page:constant RepeatWrapping] the texture will simply repeat to infinity.<br /><br />
  44. [page:constant ClampToEdgeWrapping]是默认值,纹理中的最后一个像素将延伸到网格的边缘。<br /><br />
  45. 使用[page:constant MirroredRepeatWrapping], 纹理将重复到无穷大,在每次重复时将进行镜像。
  46. </p>
  47. <h2>放大滤镜(Magnification Filters)</h2>
  48. <code>
  49. THREE.NearestFilter
  50. THREE.LinearFilter
  51. </code>
  52. <p>
  53. 这些常量用于纹理的[page:Texture.magFilter magFilter]属性,它们定义了当被纹理化的像素映射到小于或者等于1纹理元素(texel)的区域时,将要使用的纹理放大函数。<br /><br />
  54. [page:constant NearestFilter]返回与指定纹理坐标(在曼哈顿距离之内)最接近的纹理元素的值。<br /><br />
  55. [page:constant LinearFilter]是默认值,返回距离指定的纹理坐标最近的四个纹理元素的加权平均值,
  56. 并且可以包含纹理的其他部分中,被包裹或者被重复的项目,具体取决于 [page:Texture.wrapS wrapS] 和 [page:Texture.wrapT wrapT] 的值,and on the exact mapping。
  57. </p>
  58. <h2>缩小滤镜(Minification Filters)</h2>
  59. <code>
  60. THREE.NearestFilter
  61. THREE.NearestMipmapNearestFilter
  62. THREE.NearestMipmapLinearFilter
  63. THREE.LinearFilter
  64. THREE.LinearMipmapNearestFilter
  65. THREE.LinearMipmapLinearFilter
  66. </code>
  67. <p>
  68. 这些常量用于纹理的[page:Texture.minFilter minFilter]属性,它们定义了当被纹理化的像素映射到大于1纹理元素(texel)的区域时,将要使用的纹理缩小函数。<br /><br />
  69. 除了[page:constant NearestFilter] 和 [page:constant LinearFilter],
  70. 下面的四个函数也可以用于缩小:<br /><br />
  71. [page:constant NearestMipmapNearestFilter]选择与被纹理化像素的尺寸最匹配的mipmap,
  72. 并以[page:constant NearestFilter](最靠近像素中心的纹理元素)为标准来生成纹理值。
  73. <br /><br />
  74. [page:constant NearestMipmapLinearFilter]选择与被纹理化像素的尺寸最接近的两个mipmap,
  75. 并以[page:constant NearestFilter]为标准来从每个mipmap中生成纹理值。最终的纹理值是这两个值的加权平均值。
  76. <br /><br />
  77. [page:constant LinearMipmapNearestFilter]选择与被纹理化像素的尺寸最匹配的mipmap,
  78. 并以[page:constant LinearFilter](最靠近像素中心的四个纹理元素的加权平均值)为标准来生成纹理值。
  79. <br /><br />
  80. [page:constant LinearMipmapLinearFilter]是默认值,它选择与被纹理化像素的尺寸最接近的两个mipmap,
  81. 并以[page:constant LinearFilter]为标准来从每个mipmap中生成纹理值。最终的纹理值是这两个值的加权平均值。<br /><br />
  82. 请查看示例:[example:webgl_materials_texture_filters materials / texture / filters]。
  83. </p>
  84. <h2>类型</h2>
  85. <code>
  86. THREE.UnsignedByteType
  87. THREE.ByteType
  88. THREE.ShortType
  89. THREE.UnsignedShortType
  90. THREE.IntType
  91. THREE.UnsignedIntType
  92. THREE.FloatType
  93. THREE.HalfFloatType
  94. THREE.UnsignedShort4444Type
  95. THREE.UnsignedShort5551Type
  96. THREE.UnsignedShort565Type
  97. THREE.UnsignedInt248Type
  98. </code>
  99. <p>
  100. 这些常量用于纹理的[page:Texture.type type]属性,这些属性必须与正确的格式相对应。详情请查看下方。<br /><br />
  101. [page:constant UnsignedByteType] 是默认值。
  102. </p>
  103. <h2>格式</h2>
  104. <code>
  105. THREE.AlphaFormat
  106. THREE.RedFormat
  107. THREE.RedIntegerFormat
  108. THREE.RGFormat
  109. THREE.RGIntegerFormat
  110. THREE.RGBAFormat
  111. THREE.RGBAIntegerFormat
  112. THREE.LuminanceFormat
  113. THREE.LuminanceAlphaFormat
  114. THREE.DepthFormat
  115. THREE.DepthStencilFormat
  116. </code>
  117. <p>
  118. 这些常量用于纹理的[page:Texture.format format]属性,它们定义了shader(着色器)将如何读取的2D纹理或者*texels*(纹理元素)的元素。.<br /><br />
  119. [page:constant AlphaFormat] 丢弃红、绿、蓝分量,仅读取Alpha分量。<br /><br />
  120. [page:constant RedFormat] discards the green and blue components and reads just the red component.<br /><br />
  121. [page:constant RedIntegerFormat] discards the green and blue components and reads just the red component.
  122. The texels are read as integers instead of floating point.
  123. (can only be used with a WebGL 2 rendering context).
  124. <br /><br />
  125. [page:constant RGFormat] discards the alpha, and blue components and reads the red, and green components.
  126. (can only be used with a WebGL 2 rendering context).
  127. <br /><br />
  128. [page:constant RGIntegerFormat] discards the alpha, and blue components and reads the red, and green components.
  129. The texels are read as integers instead of floating point.
  130. (can only be used with a WebGL 2 rendering context).
  131. <br /><br />
  132. [page:constant RGBAFormat] 是默认值,它将读取红、绿、蓝和Alpha分量。<br /><br />
  133. [page:constant RGBAIntegerFormat] is the default and reads the red, green, blue and alpha components.
  134. The texels are read as integers instead of floating point.
  135. (can only be used with a WebGL 2 rendering context).
  136. <br /><br />
  137. [page:constant LuminanceFormat] 将每个元素作为单独的亮度分量来读取。
  138. 将其转换为范围限制在[0,1]区间的浮点数,然后通过将亮度值放入红、绿、蓝通道,并将1.0赋给Alpha通道,来组装成一个RGBA元素。<br /><br />
  139. [page:constant LuminanceAlphaFormat] 将每个元素同时作为亮度分量和Alpha分量来读取。
  140. 和上面[page:constant LuminanceFormat]的处理过程是一致的,除了Alpha分量具有除了*1.0*以外的值。<br /><br />
  141. [page:constant DepthFormat]将每个元素作为单独的深度值来读取,将其转换为范围限制在[0,1]区间的浮点数。
  142. 它是[page:DepthTexture DepthTexture]的默认值。<br /><br />
  143. [page:constant DepthStencilFormat]将每个元素同时作为一对深度值和模板值来读取。
  144. 其中的深度分量解释为[page:constant DepthFormat]。
  145. 模板分量基于深度+模板的内部格式来进行解释。
  146. <br /><br />
  147. 请注意,纹理必须具有正确的[page:Texture.type type]设置,正如上一节所描述的那样。
  148. 请参阅[link:https://developer.mozilla.org/en/docs/Web/API/WebGLRenderingContext/texImage2D WebGLRenderingContext.texImage2D]
  149. 来获得有关详细信息。
  150. </p>
  151. <h2>DDS / ST3C 压缩纹理格式</h2>
  152. <code>
  153. THREE.RGB_S3TC_DXT1_Format
  154. THREE.RGBA_S3TC_DXT1_Format
  155. THREE.RGBA_S3TC_DXT3_Format
  156. THREE.RGBA_S3TC_DXT5_Format
  157. </code>
  158. <p>
  159. 要使用[page:CompressedTexture CompressedTexture]中的[page:Texture.format format]属性,
  160. 需要获得[link:https://www.khronos.org/registry/webgl/extensions/WEBGL_compressed_texture_s3tc/ WEBGL_compressed_texture_s3tc]
  161. 扩展的支持。<br /><br />
  162. 通过这个扩展,这里的四种[link:https://en.wikipedia.org/wiki/S3_Texture_Compression S3TC]格式将可以使用:<br />
  163. [page:constant RGB_S3TC_DXT1_Format]:RGB图像格式的DXT1压缩图像。
  164. [page:constant RGBA_S3TC_DXT1_Format]:RGB图像格式的DXT1压缩图像,Alpha仅具有是/否透明两个值。<br />
  165. [page:constant RGBA_S3TC_DXT3_Format]:RGBA图像格式的DXT3压缩图像,和32位RGBA纹理贴图相比,它提供了4:1的压缩比。<br />
  166. [page:constant RGBA_S3TC_DXT5_Format]:RGBA图像格式的DXT5压缩图像,它也提供了4:1的压缩比,但与DX3格式的不同之处在于其Alpha是如何被压缩的。<br />
  167. </p>
  168. <h2>PVRTC 压缩纹理格式(PVRTC Compressed Texture Formats)</h2>
  169. <code>
  170. THREE.RGB_PVRTC_4BPPV1_Format
  171. THREE.RGB_PVRTC_2BPPV1_Format
  172. THREE.RGBA_PVRTC_4BPPV1_Format
  173. THREE.RGBA_PVRTC_2BPPV1_Format
  174. </code>
  175. <p>
  176. 要使用[page:CompressedTexture CompressedTexture]中的[page:Texture.format format]属性,需要获得
  177. [link:https://www.khronos.org/registry/webgl/extensions/WEBGL_compressed_texture_pvrtc/ WEBGL_compressed_texture_pvrtc]
  178. 扩展的支持。<br />
  179. PVRTC通常只在具有PowerVR芯片的移动设备上可用,这些设备主要是苹果设备。<br /><br />
  180. 通过这个扩展,这里的四种[link:https://en.wikipedia.org/wiki/PVRTC PVRTC]格式将可以使用:<br />
  181. [page:constant RGB_PVRTC_4BPPV1_Format]:4位模式下的RGB压缩,每4x4像素一个块。<br />
  182. [page:constant RGB_PVRTC_2BPPV1_Format]:2位模式下的RGB压缩,每8x4像素一个块。<br />
  183. [page:constant RGBA_PVRTC_4BPPV1_Format]: 4位模式下的RGBA压缩,每4x4像素一个块。<br />
  184. [page:constant RGBA_PVRTC_2BPPV1_Format]: 2位模式下的RGB压缩,每8x4像素一个块。<br />
  185. </p>
  186. <h2>ETC 压缩纹理格式</h2>
  187. <code>
  188. THREE.RGB_ETC1_Format
  189. THREE.RGB_ETC2_Format
  190. THREE.RGBA_ETC2_EAC_Format
  191. </code>
  192. <p>
  193. For use with a [page:CompressedTexture CompressedTexture]'s [page:Texture.format format] property,
  194. these require support for the [link:https://www.khronos.org/registry/webgl/extensions/WEBGL_compressed_texture_etc1/ WEBGL_compressed_texture_etc1]
  195. (ETC1) or [link:https://www.khronos.org/registry/webgl/extensions/WEBGL_compressed_texture_etc/ WEBGL_compressed_texture_etc]
  196. (ETC2) extensions. <br /><br />
  197. </p>
  198. <h2>ASTC Compressed Texture Format</h2>
  199. <code>
  200. THREE.RGBA_ASTC_4x4_Format
  201. THREE.RGBA_ASTC_5x4_Format
  202. THREE.RGBA_ASTC_5x5_Format
  203. THREE.RGBA_ASTC_6x5_Format
  204. THREE.RGBA_ASTC_6x6_Format
  205. THREE.RGBA_ASTC_8x5_Format
  206. THREE.RGBA_ASTC_8x6_Format
  207. THREE.RGBA_ASTC_8x8_Format
  208. THREE.RGBA_ASTC_10x5_Format
  209. THREE.RGBA_ASTC_10x6_Format
  210. THREE.RGBA_ASTC_10x8_Format
  211. THREE.RGBA_ASTC_10x10_Format
  212. THREE.RGBA_ASTC_12x10_Format
  213. THREE.RGBA_ASTC_12x12_Format
  214. </code>
  215. <p>
  216. For use with a [page:CompressedTexture CompressedTexture]'s [page:Texture.format format] property,
  217. these require support for the [link:https://www.khronos.org/registry/webgl/extensions/WEBGL_compressed_texture_astc/ WEBGL_compressed_texture_astc] extension. <br /><br />
  218. </p>
  219. <h2>Internal Formats</h2>
  220. <code>
  221. 'ALPHA'
  222. 'RGB'
  223. 'RGBA'
  224. 'LUMINANCE'
  225. 'LUMINANCE_ALPHA'
  226. 'RED_INTEGER'
  227. 'R8'
  228. 'R8_SNORM'
  229. 'R8I'
  230. 'R8UI'
  231. 'R16I'
  232. 'R16UI'
  233. 'R16F'
  234. 'R32I'
  235. 'R32UI'
  236. 'R32F'
  237. 'RG8'
  238. 'RG8_SNORM'
  239. 'RG8I'
  240. 'RG8UI'
  241. 'RG16I'
  242. 'RG16UI'
  243. 'RG16F'
  244. 'RG32I'
  245. 'RG32UI'
  246. 'RG32F'
  247. 'RGB565'
  248. 'RGB8'
  249. 'RGB8_SNORM'
  250. 'RGB8I'
  251. 'RGB8UI'
  252. 'RGB16I'
  253. 'RGB16UI'
  254. 'RGB16F'
  255. 'RGB32I'
  256. 'RGB32UI'
  257. 'RGB32F'
  258. 'RGB9_E5'
  259. 'SRGB8'
  260. 'R11F_G11F_B10F'
  261. 'RGBA4'
  262. 'RGBA8'
  263. 'RGBA8_SNORM'
  264. 'RGBA8I'
  265. 'RGBA8UI'
  266. 'RGBA16I'
  267. 'RGBA16UI'
  268. 'RGBA16F'
  269. 'RGBA32I'
  270. 'RGBA32UI'
  271. 'RGBA32F'
  272. 'RGB5_A1'
  273. 'RGB10_A2'
  274. 'RGB10_A2UI'
  275. 'SRGB8_ALPHA8'
  276. 'DEPTH_COMPONENT16'
  277. 'DEPTH_COMPONENT24'
  278. 'DEPTH_COMPONENT32F'
  279. 'DEPTH24_STENCIL8'
  280. 'DEPTH32F_STENCIL8'
  281. </code>
  282. <p>
  283. Heads up: changing the internal format of a texture will only affect the
  284. texture when using a WebGL 2 rendering context.<br /><br />
  285. For use with a texture's [page:Texture.internalFormat internalFormat] property,
  286. these define how elements of a texture, or *texels*, are stored on the GPU.<br /><br />
  287. [page:constant R8] stores the red component on 8 bits.<br /><br />
  288. [page:constant R8_SNORM] stores the red component on 8 bits. The component is stored as normalized. <br /><br />
  289. [page:constant R8I] stores the red component on 8 bits. The component is stored as an integer. <br /><br />
  290. [page:constant R8UI] stores the red component on 8 bits. The component is stored as an unsigned integer. <br /><br />
  291. [page:constant R16I] stores the red component on 16 bits. The component is stored as an integer. <br /><br />
  292. [page:constant R16UI] stores the red component on 16 bits. The component is stored as an unsigned integer. <br /><br />
  293. [page:constant R16F] stores the red component on 16 bits. The component is stored as floating point. <br /><br />
  294. [page:constant R32I] stores the red component on 32 bits. The component is stored as an integer. <br /><br />
  295. [page:constant R32UI] stores the red component on 32 bits. The component is stored as an unsigned integer. <br /><br />
  296. [page:constant R32F] stores the red component on 32 bits. The component is stored as floating point. <br /><br />
  297. [page:constant RG8] stores the red and green components on 8 bits each.<br /><br />
  298. [page:constant RG8_SNORM] stores the red and green components on 8 bits each.
  299. Every component is stored as normalized.
  300. <br /><br />
  301. [page:constant RG8I] stores the red and green components on 8 bits each.
  302. Every component is stored as an integer.
  303. <br /><br />
  304. [page:constant RG8UI] stores the red and green components on 8 bits each.
  305. Every component is stored as an unsigned integer.
  306. <br /><br />
  307. [page:constant RG16I] stores the red and green components on 16 bits each.
  308. Every component is stored as an integer.
  309. <br /><br />
  310. [page:constant RG16UI] stores the red and green components on 16 bits each.
  311. Every component is stored as an unsigned integer.
  312. <br /><br />
  313. [page:constant RG16F] stores the red and green components on 16 bits each.
  314. Every component is stored as floating point.
  315. <br /><br />
  316. [page:constant RG32I] stores the red and green components on 32 bits each.
  317. Every component is stored as an integer.
  318. <br /><br />
  319. [page:constant RG32UI] stores the red and green components on 32 bits.
  320. Every component is stored as an unsigned integer.
  321. <br /><br />
  322. [page:constant RG32F] stores the red and green components on 32 bits.
  323. Every component is stored as floating point.
  324. <br /><br />
  325. [page:constant RGB8] stores the red, green, and blue components on 8 bits each.
  326. [page:constant RGB8_SNORM] stores the red, green, and blue components on 8 bits each.
  327. Every component is stored as normalized.
  328. <br /><br />
  329. [page:constant RGB8I] stores the red, green, and blue components on 8 bits each.
  330. Every component is stored as an integer.
  331. <br /><br />
  332. [page:constant RGB8UI] stores the red, green, and blue components on 8 bits each.
  333. Every component is stored as an unsigned integer.
  334. <br /><br />
  335. [page:constant RGB16I] stores the red, green, and blue components on 16 bits each.
  336. Every component is stored as an integer.
  337. <br /><br />
  338. [page:constant RGB16UI] stores the red, green, and blue components on 16 bits each.
  339. Every component is stored as an unsigned integer.
  340. <br /><br />
  341. [page:constant RGB16F] stores the red, green, and blue components on 16 bits each.
  342. Every component is stored as floating point
  343. <br /><br />
  344. [page:constant RGB32I] stores the red, green, and blue components on 32 bits each.
  345. Every component is stored as an integer.
  346. <br /><br />
  347. [page:constant RGB32UI] stores the red, green, and blue components on 32 bits each.
  348. Every component is stored as an unsigned integer.
  349. <br /><br />
  350. [page:constant RGB32F] stores the red, green, and blue components on 32 bits each.
  351. Every component is stored as floating point
  352. <br /><br />
  353. [page:constant R11F_G11F_B10F] stores the red, green, and blue components respectively on 11 bits, 11 bits, and 10bits.
  354. Every component is stored as floating point.
  355. <br /><br />
  356. [page:constant RGB565] stores the red, green, and blue components respectively on 5 bits, 6 bits, and 5 bits.<br /><br />
  357. [page:constant RGB9_E5] stores the red, green, and blue components on 9 bits each.<br /><br />
  358. [page:constant RGBA8] stores the red, green, blue, and alpha components on 8 bits each.<br /><br />
  359. [page:constant RGBA8_SNORM] stores the red, green, blue, and alpha components on 8 bits.
  360. Every component is stored as normalized.
  361. <br /><br />
  362. [page:constant RGBA8I] stores the red, green, blue, and alpha components on 8 bits each.
  363. Every component is stored as an integer.
  364. <br /><br />
  365. [page:constant RGBA8UI] stores the red, green, blue, and alpha components on 8 bits.
  366. Every component is stored as an unsigned integer.
  367. <br /><br />
  368. [page:constant RGBA16I] stores the red, green, blue, and alpha components on 16 bits.
  369. Every component is stored as an integer.
  370. <br /><br />
  371. [page:constant RGBA16UI] stores the red, green, blue, and alpha components on 16 bits.
  372. Every component is stored as an unsigned integer.
  373. <br /><br />
  374. [page:constant RGBA16F] stores the red, green, blue, and alpha components on 16 bits.
  375. Every component is stored as floating point.
  376. <br /><br />
  377. [page:constant RGBA32I] stores the red, green, blue, and alpha components on 32 bits.
  378. Every component is stored as an integer.
  379. <br /><br />
  380. [page:constant RGBA32UI] stores the red, green, blue, and alpha components on 32 bits.
  381. Every component is stored as an unsigned integer.
  382. <br /><br />
  383. [page:constant RGBA32F] stores the red, green, blue, and alpha components on 32 bits.
  384. Every component is stored as floating point.
  385. <br /><br />
  386. [page:constant RGB5_A1] stores the red, green, blue, and alpha components respectively on 5 bits, 5 bits, 5 bits, and 1 bit.<br /><br />
  387. [page:constant RGB10_A2] stores the red, green, blue, and alpha components respectively on 10 bits, 10 bits, 10 bits and 2 bits.<br /><br />
  388. [page:constant RGB10_A2UI] stores the red, green, blue, and alpha components respectively on 10 bits, 10 bits, 10 bits and 2 bits.
  389. Every component is stored as an unsigned integer.
  390. <br /><br />
  391. [page:constant SRGB8] stores the red, green, and blue components on 8 bits each.<br /><br />
  392. [page:constant SRGB8_ALPHA8] stores the red, green, blue, and alpha components on 8 bits each.<br /><br />
  393. [page:constant DEPTH_COMPONENT16] stores the depth component on 16bits.<br /><br />
  394. [page:constant DEPTH_COMPONENT24] stores the depth component on 24bits.<br /><br />
  395. [page:constant DEPTH_COMPONENT32F] stores the depth component on 32bits. The component is stored as floating point.<br /><br />
  396. [page:constant DEPTH24_STENCIL8] stores the depth, and stencil components respectively on 24 bits and 8 bits.
  397. The stencil component is stored as an unsigned integer.
  398. <br /><br />
  399. [page:constant DEPTH32F_STENCIL8] stores the depth, and stencil components respectively on 32 bits and 8 bits.
  400. The depth component is stored as floating point, and the stencil component as an unsigned integer.
  401. <br /><br />
  402. Note that the texture must have the correct [page:Texture.type type] set,
  403. as well as the correct [page:Texture.format format].
  404. See [link:https://developer.mozilla.org/en/docs/Web/API/WebGLRenderingContext/texImage2D WebGLRenderingContext.texImage2D], and
  405. [link:https://developer.mozilla.org/en-US/docs/Web/API/WebGL2RenderingContext/texImage3D WebGL2RenderingContext.texImage3D],
  406. for more details regarding the possible combination of [page:Texture.format format], [page:Texture.internalFormat internalFormat],
  407. and [page:Texture.type type].<br /><br />
  408. For more in-depth information regarding internal formats, you can also refer directly
  409. to the [link:https://www.khronos.org/registry/webgl/specs/latest/2.0/ WebGL2 Specification] and
  410. to the [link:https://www.khronos.org/registry/OpenGL/specs/es/3.0/es_spec_3.0.pdf OpenGL ES 3.0 Specification].
  411. </p>
  412. <h2>编码</h2>
  413. <code>
  414. THREE.LinearEncoding
  415. THREE.sRGBEncoding
  416. THREE.BasicDepthPacking
  417. THREE.RGBADepthPacking
  418. </code>
  419. <p>
  420. 这些常量用于纹理的[page:Texture.encoding encoding]属性。<br /><br />
  421. 如果编码类型在纹理已被一个材质使用之后发生了改变,
  422. 你需要来设置[page:Material.needsUpdate Material.needsUpdate]为*true*来使得材质重新编译。<br /><br />
  423. [page:constant LinearEncoding]是默认值。
  424. 除此之外的其他值仅在材质的贴图、envMap和emissiveMap中有效。
  425. </p>
  426. <h2>源代码</h2>
  427. <p>
  428. [link:https://github.com/mrdoob/three.js/blob/master/src/constants.js src/constants.js]
  429. </p>
  430. </body>
  431. </html>