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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. </code>
  20. <p>
  21. 这些常量定义了纹理贴图的映射模式。<br />
  22. [page:Constant UVMapping]是默认值,纹理使用网格的坐标来进行映射。<br /><br />
  23. 其它的值定义了环境映射的类型。<br /><br />
  24. [page:Constant CubeReflectionMapping] 和 [page:Constant CubeRefractionMapping] 用于 [page:CubeTexture CubeTexture] ——
  25. 由6个纹理组合而成,每个纹理都是立方体的一个面。
  26. 对于[page:CubeTexture CubeTexture]来说,[page:Constant CubeReflectionMapping]是其默认值。<br /><br />
  27. [page:Constant EquirectangularReflectionMapping] 和 [page:Constant EquirectangularRefractionMapping]
  28. 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。
  29. <br /><br />
  30. 请查看示例:[example:webgl_materials_envmaps materials / envmaps] 。
  31. </p>
  32. <h2>包裹模式</h2>
  33. <code>
  34. THREE.RepeatWrapping
  35. THREE.ClampToEdgeWrapping
  36. THREE.MirroredRepeatWrapping
  37. </code>
  38. <p>
  39. 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。
  40. <br /><br />
  41. 使用[page:constant RepeatWrapping],纹理将简单地重复到无穷大。
  42. With [page:constant RepeatWrapping] the texture will simply repeat to infinity.<br /><br />
  43. [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 />
  44. 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。
  45. </p>
  46. <h2>放大滤镜(Magnification Filters)</h2>
  47. <code>
  48. THREE.NearestFilter
  49. THREE.LinearFilter
  50. </code>
  51. <p>
  52. 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 />
  53. [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 />
  54. [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,
  55. 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。
  56. </p>
  57. <h2>缩小滤镜(Minification Filters)</h2>
  58. <code>
  59. THREE.NearestFilter
  60. THREE.NearestMipmapNearestFilter
  61. THREE.NearestMipmapLinearFilter
  62. THREE.LinearFilter
  63. THREE.LinearMipmapNearestFilter
  64. THREE.LinearMipmapLinearFilter
  65. </code>
  66. <p>
  67. 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 />
  68. 除了[page:constant NearestFilter] 和 [page:constant LinearFilter],
  69. 下面的四个函数也可以用于缩小:<br /><br />
  70. [page:constant NearestMipmapNearestFilter]选择与被纹理化像素的尺寸最匹配的mipmap,
  71. 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。
  72. <br /><br />
  73. [page:constant NearestMipmapLinearFilter]选择与被纹理化像素的尺寸最接近的两个mipmap,
  74. 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。
  75. <br /><br />
  76. [page:constant LinearMipmapNearestFilter]选择与被纹理化像素的尺寸最匹配的mipmap,
  77. 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。
  78. <br /><br />
  79. [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,
  80. 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 />
  81. 请查看示例:[example:webgl_materials_texture_filters materials / texture / filters]。
  82. </p>
  83. <h2>类型</h2>
  84. <code>
  85. THREE.UnsignedByteType
  86. THREE.ByteType
  87. THREE.ShortType
  88. THREE.UnsignedShortType
  89. THREE.IntType
  90. THREE.UnsignedIntType
  91. THREE.FloatType
  92. THREE.HalfFloatType
  93. THREE.UnsignedShort4444Type
  94. THREE.UnsignedShort5551Type
  95. THREE.UnsignedInt248Type
  96. </code>
  97. <p>
  98. 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 />
  99. [page:constant UnsignedByteType] 是默认值。
  100. </p>
  101. <h2>格式</h2>
  102. <code>
  103. THREE.AlphaFormat
  104. THREE.RedFormat
  105. THREE.RedIntegerFormat
  106. THREE.RGFormat
  107. THREE.RGIntegerFormat
  108. THREE.RGBAFormat
  109. THREE.RGBAIntegerFormat
  110. THREE.LuminanceFormat
  111. THREE.LuminanceAlphaFormat
  112. THREE.DepthFormat
  113. THREE.DepthStencilFormat
  114. </code>
  115. <p>
  116. 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 />
  117. [page:constant AlphaFormat] 丢弃红、绿、蓝分量,仅读取Alpha分量。<br /><br />
  118. [page:constant RedFormat] discards the green and blue components and reads just the red component.<br /><br />
  119. [page:constant RedIntegerFormat] discards the green and blue components and reads just the red component.
  120. The texels are read as integers instead of floating point.
  121. (can only be used with a WebGL 2 rendering context).
  122. <br /><br />
  123. [page:constant RGFormat] discards the alpha, and blue components and reads the red, and green components.
  124. (can only be used with a WebGL 2 rendering context).
  125. <br /><br />
  126. [page:constant RGIntegerFormat] discards the alpha, and blue components and reads the red, and green components.
  127. The texels are read as integers instead of floating point.
  128. (can only be used with a WebGL 2 rendering context).
  129. <br /><br />
  130. [page:constant RGBAFormat] 是默认值,它将读取红、绿、蓝和Alpha分量。<br /><br />
  131. [page:constant RGBAIntegerFormat] is the default and reads the red, green, blue and alpha components.
  132. The texels are read as integers instead of floating point.
  133. (can only be used with a WebGL 2 rendering context).
  134. <br /><br />
  135. [page:constant LuminanceFormat] 将每个元素作为单独的亮度分量来读取。
  136. 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 />
  137. [page:constant LuminanceAlphaFormat] 将每个元素同时作为亮度分量和Alpha分量来读取。
  138. 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 />
  139. [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。
  140. 它是[page:DepthTexture DepthTexture]的默认值。<br /><br />
  141. [page:constant DepthStencilFormat]将每个元素同时作为一对深度值和模板值来读取。
  142. 其中的深度分量解释为[page:constant DepthFormat]。
  143. 模板分量基于深度+模板的内部格式来进行解释。
  144. <br /><br />
  145. 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。
  146. 请参阅[link:https://developer.mozilla.org/en/docs/Web/API/WebGLRenderingContext/texImage2D WebGLRenderingContext.texImage2D]
  147. 来获得有关详细信息。
  148. </p>
  149. <h2>DDS / ST3C 压缩纹理格式</h2>
  150. <code>
  151. THREE.RGB_S3TC_DXT1_Format
  152. THREE.RGBA_S3TC_DXT1_Format
  153. THREE.RGBA_S3TC_DXT3_Format
  154. THREE.RGBA_S3TC_DXT5_Format
  155. </code>
  156. <p>
  157. 要使用[page:CompressedTexture CompressedTexture]中的[page:Texture.format format]属性,
  158. 需要获得[link:https://www.khronos.org/registry/webgl/extensions/WEBGL_compressed_texture_s3tc/ WEBGL_compressed_texture_s3tc]
  159. 扩展的支持。<br /><br />
  160. 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 />
  161. [page:constant RGB_S3TC_DXT1_Format]:RGB图像格式的DXT1压缩图像。
  162. [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 />
  163. [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 />
  164. [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 />
  165. </p>
  166. <h2>PVRTC 压缩纹理格式(PVRTC Compressed Texture Formats)</h2>
  167. <code>
  168. THREE.RGB_PVRTC_4BPPV1_Format
  169. THREE.RGB_PVRTC_2BPPV1_Format
  170. THREE.RGBA_PVRTC_4BPPV1_Format
  171. THREE.RGBA_PVRTC_2BPPV1_Format
  172. </code>
  173. <p>
  174. 要使用[page:CompressedTexture CompressedTexture]中的[page:Texture.format format]属性,需要获得
  175. [link:https://www.khronos.org/registry/webgl/extensions/WEBGL_compressed_texture_pvrtc/ WEBGL_compressed_texture_pvrtc]
  176. 扩展的支持。<br />
  177. 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 />
  178. 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 />
  179. [page:constant RGB_PVRTC_4BPPV1_Format]:4位模式下的RGB压缩,每4x4像素一个块。<br />
  180. [page:constant RGB_PVRTC_2BPPV1_Format]:2位模式下的RGB压缩,每8x4像素一个块。<br />
  181. [page:constant RGBA_PVRTC_4BPPV1_Format]: 4位模式下的RGBA压缩,每4x4像素一个块。<br />
  182. [page:constant RGBA_PVRTC_2BPPV1_Format]: 2位模式下的RGB压缩,每8x4像素一个块。<br />
  183. </p>
  184. <h2>ETC 压缩纹理格式</h2>
  185. <code>
  186. THREE.RGB_ETC1_Format
  187. THREE.RGB_ETC2_Format
  188. THREE.RGBA_ETC2_EAC_Format
  189. </code>
  190. <p>
  191. For use with a [page:CompressedTexture CompressedTexture]'s [page:Texture.format format] property,
  192. these require support for the [link:https://www.khronos.org/registry/webgl/extensions/WEBGL_compressed_texture_etc1/ WEBGL_compressed_texture_etc1]
  193. (ETC1) or [link:https://www.khronos.org/registry/webgl/extensions/WEBGL_compressed_texture_etc/ WEBGL_compressed_texture_etc]
  194. (ETC2) extensions. <br /><br />
  195. </p>
  196. <h2>ASTC Compressed Texture Format</h2>
  197. <code>
  198. THREE.RGBA_ASTC_4x4_Format
  199. THREE.RGBA_ASTC_5x4_Format
  200. THREE.RGBA_ASTC_5x5_Format
  201. THREE.RGBA_ASTC_6x5_Format
  202. THREE.RGBA_ASTC_6x6_Format
  203. THREE.RGBA_ASTC_8x5_Format
  204. THREE.RGBA_ASTC_8x6_Format
  205. THREE.RGBA_ASTC_8x8_Format
  206. THREE.RGBA_ASTC_10x5_Format
  207. THREE.RGBA_ASTC_10x6_Format
  208. THREE.RGBA_ASTC_10x8_Format
  209. THREE.RGBA_ASTC_10x10_Format
  210. THREE.RGBA_ASTC_12x10_Format
  211. THREE.RGBA_ASTC_12x12_Format
  212. </code>
  213. <p>
  214. For use with a [page:CompressedTexture CompressedTexture]'s [page:Texture.format format] property,
  215. these require support for the [link:https://www.khronos.org/registry/webgl/extensions/WEBGL_compressed_texture_astc/ WEBGL_compressed_texture_astc] extension. <br /><br />
  216. </p>
  217. <h2>Internal Formats</h2>
  218. <code>
  219. 'ALPHA'
  220. 'RGB'
  221. 'RGBA'
  222. 'LUMINANCE'
  223. 'LUMINANCE_ALPHA'
  224. 'RED_INTEGER'
  225. 'R8'
  226. 'R8_SNORM'
  227. 'R8I'
  228. 'R8UI'
  229. 'R16I'
  230. 'R16UI'
  231. 'R16F'
  232. 'R32I'
  233. 'R32UI'
  234. 'R32F'
  235. 'RG8'
  236. 'RG8_SNORM'
  237. 'RG8I'
  238. 'RG8UI'
  239. 'RG16I'
  240. 'RG16UI'
  241. 'RG16F'
  242. 'RG32I'
  243. 'RG32UI'
  244. 'RG32F'
  245. 'RGB565'
  246. 'RGB8'
  247. 'RGB8_SNORM'
  248. 'RGB8I'
  249. 'RGB8UI'
  250. 'RGB16I'
  251. 'RGB16UI'
  252. 'RGB16F'
  253. 'RGB32I'
  254. 'RGB32UI'
  255. 'RGB32F'
  256. 'RGB9_E5'
  257. 'SRGB8'
  258. 'R11F_G11F_B10F'
  259. 'RGBA4'
  260. 'RGBA8'
  261. 'RGBA8_SNORM'
  262. 'RGBA8I'
  263. 'RGBA8UI'
  264. 'RGBA16I'
  265. 'RGBA16UI'
  266. 'RGBA16F'
  267. 'RGBA32I'
  268. 'RGBA32UI'
  269. 'RGBA32F'
  270. 'RGB5_A1'
  271. 'RGB10_A2'
  272. 'RGB10_A2UI'
  273. 'SRGB8_ALPHA8'
  274. 'DEPTH_COMPONENT16'
  275. 'DEPTH_COMPONENT24'
  276. 'DEPTH_COMPONENT32F'
  277. 'DEPTH24_STENCIL8'
  278. 'DEPTH32F_STENCIL8'
  279. </code>
  280. <p>
  281. Heads up: changing the internal format of a texture will only affect the
  282. texture when using a WebGL 2 rendering context.<br /><br />
  283. For use with a texture's [page:Texture.internalFormat internalFormat] property,
  284. these define how elements of a texture, or *texels*, are stored on the GPU.<br /><br />
  285. [page:constant R8] stores the red component on 8 bits.<br /><br />
  286. [page:constant R8_SNORM] stores the red component on 8 bits. The component is stored as normalized. <br /><br />
  287. [page:constant R8I] stores the red component on 8 bits. The component is stored as an integer. <br /><br />
  288. [page:constant R8UI] stores the red component on 8 bits. The component is stored as an unsigned integer. <br /><br />
  289. [page:constant R16I] stores the red component on 16 bits. The component is stored as an integer. <br /><br />
  290. [page:constant R16UI] stores the red component on 16 bits. The component is stored as an unsigned integer. <br /><br />
  291. [page:constant R16F] stores the red component on 16 bits. The component is stored as floating point. <br /><br />
  292. [page:constant R32I] stores the red component on 32 bits. The component is stored as an integer. <br /><br />
  293. [page:constant R32UI] stores the red component on 32 bits. The component is stored as an unsigned integer. <br /><br />
  294. [page:constant R32F] stores the red component on 32 bits. The component is stored as floating point. <br /><br />
  295. [page:constant RG8] stores the red and green components on 8 bits each.<br /><br />
  296. [page:constant RG8_SNORM] stores the red and green components on 8 bits each.
  297. Every component is stored as normalized.
  298. <br /><br />
  299. [page:constant RG8I] stores the red and green components on 8 bits each.
  300. Every component is stored as an integer.
  301. <br /><br />
  302. [page:constant RG8UI] stores the red and green components on 8 bits each.
  303. Every component is stored as an unsigned integer.
  304. <br /><br />
  305. [page:constant RG16I] stores the red and green components on 16 bits each.
  306. Every component is stored as an integer.
  307. <br /><br />
  308. [page:constant RG16UI] stores the red and green components on 16 bits each.
  309. Every component is stored as an unsigned integer.
  310. <br /><br />
  311. [page:constant RG16F] stores the red and green components on 16 bits each.
  312. Every component is stored as floating point.
  313. <br /><br />
  314. [page:constant RG32I] stores the red and green components on 32 bits each.
  315. Every component is stored as an integer.
  316. <br /><br />
  317. [page:constant RG32UI] stores the red and green components on 32 bits.
  318. Every component is stored as an unsigned integer.
  319. <br /><br />
  320. [page:constant RG32F] stores the red and green components on 32 bits.
  321. Every component is stored as floating point.
  322. <br /><br />
  323. [page:constant RGB8] stores the red, green, and blue components on 8 bits each.
  324. [page:constant RGB8_SNORM] stores the red, green, and blue components on 8 bits each.
  325. Every component is stored as normalized.
  326. <br /><br />
  327. [page:constant RGB8I] stores the red, green, and blue components on 8 bits each.
  328. Every component is stored as an integer.
  329. <br /><br />
  330. [page:constant RGB8UI] stores the red, green, and blue components on 8 bits each.
  331. Every component is stored as an unsigned integer.
  332. <br /><br />
  333. [page:constant RGB16I] stores the red, green, and blue components on 16 bits each.
  334. Every component is stored as an integer.
  335. <br /><br />
  336. [page:constant RGB16UI] stores the red, green, and blue components on 16 bits each.
  337. Every component is stored as an unsigned integer.
  338. <br /><br />
  339. [page:constant RGB16F] stores the red, green, and blue components on 16 bits each.
  340. Every component is stored as floating point
  341. <br /><br />
  342. [page:constant RGB32I] stores the red, green, and blue components on 32 bits each.
  343. Every component is stored as an integer.
  344. <br /><br />
  345. [page:constant RGB32UI] stores the red, green, and blue components on 32 bits each.
  346. Every component is stored as an unsigned integer.
  347. <br /><br />
  348. [page:constant RGB32F] stores the red, green, and blue components on 32 bits each.
  349. Every component is stored as floating point
  350. <br /><br />
  351. [page:constant R11F_G11F_B10F] stores the red, green, and blue components respectively on 11 bits, 11 bits, and 10bits.
  352. Every component is stored as floating point.
  353. <br /><br />
  354. [page:constant RGB565] stores the red, green, and blue components respectively on 5 bits, 6 bits, and 5 bits.<br /><br />
  355. [page:constant RGB9_E5] stores the red, green, and blue components on 9 bits each.<br /><br />
  356. [page:constant RGBA8] stores the red, green, blue, and alpha components on 8 bits each.<br /><br />
  357. [page:constant RGBA8_SNORM] stores the red, green, blue, and alpha components on 8 bits.
  358. Every component is stored as normalized.
  359. <br /><br />
  360. [page:constant RGBA8I] stores the red, green, blue, and alpha components on 8 bits each.
  361. Every component is stored as an integer.
  362. <br /><br />
  363. [page:constant RGBA8UI] stores the red, green, blue, and alpha components on 8 bits.
  364. Every component is stored as an unsigned integer.
  365. <br /><br />
  366. [page:constant RGBA16I] stores the red, green, blue, and alpha components on 16 bits.
  367. Every component is stored as an integer.
  368. <br /><br />
  369. [page:constant RGBA16UI] stores the red, green, blue, and alpha components on 16 bits.
  370. Every component is stored as an unsigned integer.
  371. <br /><br />
  372. [page:constant RGBA16F] stores the red, green, blue, and alpha components on 16 bits.
  373. Every component is stored as floating point.
  374. <br /><br />
  375. [page:constant RGBA32I] stores the red, green, blue, and alpha components on 32 bits.
  376. Every component is stored as an integer.
  377. <br /><br />
  378. [page:constant RGBA32UI] stores the red, green, blue, and alpha components on 32 bits.
  379. Every component is stored as an unsigned integer.
  380. <br /><br />
  381. [page:constant RGBA32F] stores the red, green, blue, and alpha components on 32 bits.
  382. Every component is stored as floating point.
  383. <br /><br />
  384. [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 />
  385. [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 />
  386. [page:constant RGB10_A2UI] stores the red, green, blue, and alpha components respectively on 10 bits, 10 bits, 10 bits and 2 bits.
  387. Every component is stored as an unsigned integer.
  388. <br /><br />
  389. [page:constant SRGB8] stores the red, green, and blue components on 8 bits each.<br /><br />
  390. [page:constant SRGB8_ALPHA8] stores the red, green, blue, and alpha components on 8 bits each.<br /><br />
  391. [page:constant DEPTH_COMPONENT16] stores the depth component on 16bits.<br /><br />
  392. [page:constant DEPTH_COMPONENT24] stores the depth component on 24bits.<br /><br />
  393. [page:constant DEPTH_COMPONENT32F] stores the depth component on 32bits. The component is stored as floating point.<br /><br />
  394. [page:constant DEPTH24_STENCIL8] stores the depth, and stencil components respectively on 24 bits and 8 bits.
  395. The stencil component is stored as an unsigned integer.
  396. <br /><br />
  397. [page:constant DEPTH32F_STENCIL8] stores the depth, and stencil components respectively on 32 bits and 8 bits.
  398. The depth component is stored as floating point, and the stencil component as an unsigned integer.
  399. <br /><br />
  400. Note that the texture must have the correct [page:Texture.type type] set,
  401. as well as the correct [page:Texture.format format].
  402. See [link:https://developer.mozilla.org/en/docs/Web/API/WebGLRenderingContext/texImage2D WebGLRenderingContext.texImage2D], and
  403. [link:https://developer.mozilla.org/en-US/docs/Web/API/WebGL2RenderingContext/texImage3D WebGL2RenderingContext.texImage3D],
  404. for more details regarding the possible combination of [page:Texture.format format], [page:Texture.internalFormat internalFormat],
  405. and [page:Texture.type type].<br /><br />
  406. For more in-depth information regarding internal formats, you can also refer directly
  407. to the [link:https://www.khronos.org/registry/webgl/specs/latest/2.0/ WebGL2 Specification] and
  408. to the [link:https://www.khronos.org/registry/OpenGL/specs/es/3.0/es_spec_3.0.pdf OpenGL ES 3.0 Specification].
  409. </p>
  410. <h2>编码</h2>
  411. <code>
  412. THREE.LinearEncoding
  413. THREE.sRGBEncoding
  414. THREE.BasicDepthPacking
  415. THREE.RGBADepthPacking
  416. </code>
  417. <p>
  418. 这些常量用于纹理的[page:Texture.encoding encoding]属性。<br /><br />
  419. 如果编码类型在纹理已被一个材质使用之后发生了改变,
  420. 你需要来设置[page:Material.needsUpdate Material.needsUpdate]为*true*来使得材质重新编译。<br /><br />
  421. [page:constant LinearEncoding]是默认值。
  422. 除此之外的其他值仅在材质的贴图、envMap和emissiveMap中有效。
  423. </p>
  424. <h2>源代码</h2>
  425. <p>
  426. [link:https://github.com/mrdoob/three.js/blob/master/src/constants.js src/constants.js]
  427. </p>
  428. </body>
  429. </html>