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BufferAttribute.html 9.4 KB

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  1. <!DOCTYPE html>
  2. <html lang="en">
  3. <head>
  4. <meta charset="utf-8" />
  5. <base href="../../../" />
  6. <script src="list.js"></script>
  7. <script src="page.js"></script>
  8. <link type="text/css" rel="stylesheet" href="page.css" />
  9. </head>
  10. <body>
  11. <h1>[name]</h1>
  12. <p class="desc">
  13. This class stores data for an attribute (such as vertex positions, face indices, normals,
  14. colors, UVs, and any custom attributes ) associated with a [page:BufferGeometry], which allows
  15. for more efficient passing of data to the GPU. See that page for details and a usage example.<br /><br />
  16. Data is stored as vectors of any length (defined by [page:BufferAttribute.itemSize itemSize]),
  17. and in general in the methods outlined below if passing in an index, this is automatically
  18. multiplied by the vector length.
  19. </p>
  20. <h2>Constructor</h2>
  21. <h3>[name]( [param:TypedArray array], [param:Integer itemSize], [param:Boolean normalized] )</h3>
  22. <p>
  23. [page:TypedArray array] -- Must be a [link:https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/TypedArray TypedArray].
  24. Used to instantiate the buffer. <br />
  25. This array should have
  26. <code>itemSize * numVertices</code>
  27. elements, where numVertices is the number of vertices in the associated [page:BufferGeometry BufferGeometry].<br /><br />
  28. [page:Integer itemSize] -- the number of values of the array that should be associated with
  29. a particular vertex. For instance, if this
  30. attribute is storing a 3-component vector (such as a position, normal, or color), then itemSize should be 3.
  31. <br /><br />
  32. [page:Boolean normalized] -- (optional) Applies to integer data only. Indicates how the underlying data
  33. in the buffer maps to the values in the GLSL code. For instance, if [page:TypedArray array] is an instance
  34. of UInt16Array, and [page:Boolean normalized] is true, the values 0 - +65535 in the array
  35. data will be mapped to 0.0f - +1.0f in the GLSL attribute. An Int16Array (signed) would map
  36. from -32767 - +32767 to -1.0f - +1.0f. If [page:Boolean normalized] is false, the values
  37. will be converted to floats unmodified, i.e. 32767 becomes 32767.0f.
  38. </p>
  39. <h2>Properties</h2>
  40. <h3>[property:TypedArray array]</h3>
  41. <p>
  42. The [page:TypedArray array] holding data stored in the buffer.
  43. </p>
  44. <h3>[property:Integer count]</h3>
  45. <p>
  46. Stores the [page:BufferAttribute.array array]'s length divided by the [page:BufferAttribute.itemSize itemSize].<br /><br />
  47. If the buffer is storing a 3-component vector (such as a position, normal, or color),
  48. then this will count the number of such vectors stored.
  49. </p>
  50. <h3>[property:Boolean dynamic]</h3>
  51. <p>
  52. Whether the buffer is dynamic or not. Default is *false*.<br />
  53. If false, the GPU is informed that contents of the buffer are likely to be used often and not change often.
  54. This corresponds to the [link:https://developer.mozilla.org/en-US/docs/Web/API/WebGLRenderingContext/bufferData gl.STATIC_DRAW] flag.<br />
  55. if true, the GPU is informed that contents of the buffer are likely to be used often and change often.
  56. This corresponds to the [link:https://developer.mozilla.org/en-US/docs/Web/API/WebGLRenderingContext/bufferData gl.DYNAMIC_DRAW] flag.
  57. </p>
  58. <h3>[property:Boolean isBufferAttribute]</h3>
  59. <p>
  60. Used to check whether this or derived classes are BufferAttributes. Default is *true*.<br /><br />
  61. You should not change this, as it used internally for optimisation.
  62. </p>
  63. <h3>[property:Integer itemSize]</h3>
  64. <p>The length of vectors that are being stored in the [page:BufferAttribute.array array].</p>
  65. <h3>[property:String name]</h3>
  66. <p>
  67. Optional name for this attribute instance. Default is an empty string.
  68. </p>
  69. <h3>[property:Boolean needsUpdate]</h3>
  70. <p>
  71. Flag to indicate that this attribute has changed and should be re-sent to the GPU.
  72. Set this to true when you modify the value of the array.<br /><br />
  73. Setting this to true also increments the [page:BufferAttribute.version version].
  74. </p>
  75. <h3>[property:Boolean normalized]</h3>
  76. <p>
  77. Indicates how the underlying data in the buffer maps to the values in the GLSL shader code.
  78. See the constructor above for details.
  79. </p>
  80. <h3>[property:Function onUploadCallback]</h3>
  81. <p>
  82. A callback function that is executed after the Renderer has transferred the attribute array data to the GPU.
  83. </p>
  84. <h3>[property:Object updateRange]</h3>
  85. <p>Object containing:<br />
  86. [page:Integer offset]: Default is *0*. Position at which to start update.<br />
  87. [page:Integer count]: Default is *-1*, which means don't use update ranges. <br /><br />
  88. This can be used to only update some components of stored vectors (for example, just the component
  89. related to color).
  90. </p>
  91. <h3>[property:Integer version]</h3>
  92. <p>A version number, incremented every time the [page:BufferAttribute.needsUpdate needsUpdate] property is set to true.</p>
  93. <h2>Methods</h2>
  94. <h3>[method:BufferAttribute clone]() </h3>
  95. <p>Return a copy of this bufferAttribute.</p>
  96. <h3>[method:BufferAttribute copy]( [param:BufferAttribute bufferAttribute] )</h3>
  97. <p>Copies another BufferAttribute to this BufferAttribute.</p>
  98. <h3>[method:BufferAttribute copyArray]( array ) </h3>
  99. <p>Copy the array given here (which can be a normal array or TypedArray) into
  100. [page:BufferAttribute.array array].<br /><br />
  101. See [link:https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray/set TypedArray.set]
  102. for notes on requirements if copying a TypedArray.
  103. </p>
  104. <h3>[method:null copyAt] ( [param:Integer index1], [param:BufferAttribute bufferAttribute], [param:Integer index2] ) </h3>
  105. <p>Copy a vector from bufferAttribute[index2] to [page:BufferAttribute.array array][index1].</p>
  106. <h3>[method:BufferAttribute copyColorsArray]( [param:Array colors] ) </h3>
  107. <p>Copy an array representing RGB color values into [page:BufferAttribute.array array].</p>
  108. <h3>[method:BufferAttribute copyVector2sArray]( [param:Array vectors] ) </h3>
  109. <p>Copy an array representing [page:Vector2]s into [page:BufferAttribute.array array].</p>
  110. <h3>[method:BufferAttribute copyVector3sArray]( [param:Array vectors] ) </h3>
  111. <p>Copy an array representing [page:Vector3]s into [page:BufferAttribute.array array].</p>
  112. <h3>[method:BufferAttribute copyVector4sArray]( [param:Array vectors] ) </h3>
  113. <p>Copy an array representing [page:Vector4]s into [page:BufferAttribute.array array].</p>
  114. <h3>[method:Number getX]( [param:Integer index] ) </h3>
  115. <p>Returns the x component of the vector at the given index.</p>
  116. <h3>[method:Number getY]( [param:Integer index] ) </h3>
  117. <p>Returns the y component of the vector at the given index.</p>
  118. <h3>[method:Number getZ]( [param:Integer index] ) </h3>
  119. <p>Returns the z component of the vector at the given index.</p>
  120. <h3>[method:Number getW]( [param:Integer index] ) </h3>
  121. <p>Returns the w component of the vector at the given index.</p>
  122. <h3>[method:null onUpload]( [param:Function callback] ) </h3>
  123. <p>
  124. Sets the value of the onUploadCallback property.<br /><br />
  125. In the [example:webgl_buffergeometry WebGL / Buffergeometry] this is used to free memory
  126. after the buffer has been transferred to the GPU.
  127. </p>
  128. <h3>[method:BufferAttribute set] ( [param:Array value], [param:Integer offset] ) </h3>
  129. <p>
  130. value -- an [page:Array] or [page:TypedArray] from which to copy values. <br />
  131. offset -- (optional) index of the [page:BufferAttribute.array array] at which to start copying.<br /><br />
  132. Calls [link:https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray/set TypedArray.set]( [page:Array value], [page:Integer offset] )
  133. on the [page:BufferAttribute.array array].<br /><br />
  134. In particular, see that page for requirements on [page:Array value]
  135. being a [page:TypedArray].
  136. </p>
  137. <h3>[method:BufferAttribute setArray] ( [param:TypedArray array] ) </h3>
  138. <p>
  139. [page:BufferAttribute.array array] to the TypedArray passed in here.<br /><br />
  140. After setting the array, [page:BufferAttribute.needsUpdate needsUpdate] should be set to true.
  141. </p>
  142. <h3>[method:BufferAttribute setDynamic] ( [param:Boolean value] ) </h3>
  143. <p>Set [page:BufferAttribute.dynamic dynamic] to value.</p>
  144. <h3>[method:BufferAttribute setX]( [param:Integer index], [param:Float x] ) </h3>
  145. <p>Sets the x component of the vector at the given index.</p>
  146. <h3>[method:BufferAttribute setY]( [param:Integer index], [param:Float y] ) </h3>
  147. <p>Sets the y component of the vector at the given index.</p>
  148. <h3>[method:BufferAttribute setZ]( [param:Integer index], [param:Float z] ) </h3>
  149. <p>Sets the z component of the vector at the given index.</p>
  150. <h3>[method:BufferAttribute setW]( [param:Integer index], [param:Float w] ) </h3>
  151. <p>Sets the w component of the vector at the given index.</p>
  152. <h3>[method:BufferAttribute setXY]( [param:Integer index], [param:Float x], [param:Float y] ) </h3>
  153. <p>Sets the x and y components of the vector at the given index.</p>
  154. <h3>[method:BufferAttribute setXYZ]( [param:Integer index], [param:Float x], [param:Float y], [param:Float z] ) </h3>
  155. <p>Sets the x, y and z components of the vector at the given index.</p>
  156. <h3>[method:BufferAttribute setXYZW]( [param:Integer index], [param:Float x], [param:Float y], [param:Float z], [param:Float w] ) </h3>
  157. <p>Sets the x, y, z and w components of the vector at the given index.</p>
  158. <h2>Source</h2>
  159. [link:https://github.com/mrdoob/three.js/blob/master/src/[path].js src/[path].js]
  160. </body>
  161. </html>