ActionScript® 3.0 Reference for the Adobe® Flash® Platform
Home  |  Show Packages and Classes List |  Packages  |  Classes  |  What's New  |  Index  |  Appendixes
flash.display3D 

VertexBuffer3D  - AS3

Packageflash.display3D
Classpublic class VertexBuffer3D
InheritanceVertexBuffer3D Inheritance Object

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 11, AIR 3

The VertexBuffer3D class represents a set of vertex data uploaded to a rendering context.

Use a VertexBuffer3D object to define the data associated with each point in a set of vertexes. You can upload the vertex data either from a Vector array or a ByteArray. (Once uploaded, the data in the original array is no longer referenced; changing or discarding the source array does not change the vertex data.)

The data associated with each vertex is in an application-defined format and is used as the input for the vertex shader program. Identify which values belong to which vertex program input using the Context3D setVertexBufferAt() function. A vertex program can use up to eight inputs (also known as vertex attribute registers). Each input can require between one and four 32-bit values. For example, the [x,y,z] position coordinates of a vertex can be passed to a vertex program as a vector containing three 32 bit values. The Context3DVertexBufferFormat class defines constants for the supported formats for shader inputs. You can supply up to sixty-four 32-bit values (256 bytes) of data for each point (but a single vertex shader cannot use all of the data in this case).

The setVertexBufferAt() function also identifies which vertex buffer to use for rendering any subsequent drawTriangles() calls. To render data from a different vertex buffer, call setVertexBufferAt() again with the appropriate arguments. (You can store data for the same point in multiple vertex buffers, say position data in one buffer and texture coordinates in another, but typically rendering is more efficient if all the data for a point comes from a single buffer.)

The Index3DBuffer object passed to the Context3D drawTriangles() method organizes the vertex data into triangles. Each value in the index buffer is the index to a vertex in the vertex buffer. A set of three indexes, in sequence, defines a triangle.

You cannot create a VertexBuffer3D object directly. Use the Context3D createVertexBuffer() method instead.

To free the render context resources associated with a vertex buffer, call the object's dispose() method.

View the examples

Related API Elements



Public Properties
 PropertyDefined By
 Inheritedconstructor : Object
A reference to the class object or constructor function for a given object instance.
Object
Public Methods
 MethodDefined By
  
Frees all resources associated with this object.
VertexBuffer3D
 Inherited
Indicates whether an object has a specified property defined.
Object
 Inherited
Indicates whether an instance of the Object class is in the prototype chain of the object specified as the parameter.
Object
 Inherited
Indicates whether the specified property exists and is enumerable.
Object
 Inherited
Sets the availability of a dynamic property for loop operations.
Object
 Inherited
Returns the string representation of this object, formatted according to locale-specific conventions.
Object
 Inherited
Returns the string representation of the specified object.
Object
  
uploadFromByteArray(data:ByteArray, byteArrayOffset:int, startVertex:int, numVertices:int):void
Uploads the data for a set of points to the rendering context from a byte array.
VertexBuffer3D
  
uploadFromVector(data:Vector.<Number>, startVertex:int, numVertices:int):void
Uploads the data for a set of points to the rendering context from a vector array.
VertexBuffer3D
 Inherited
Returns the primitive value of the specified object.
Object
Method Detail

dispose

()method
public function dispose():void

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 11, AIR 3

Frees all resources associated with this object. After disposing a vertex buffer, calling upload() and rendering using this object will fail.

uploadFromByteArray

()method 
public function uploadFromByteArray(data:ByteArray, byteArrayOffset:int, startVertex:int, numVertices:int):void

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 11, AIR 3

Uploads the data for a set of points to the rendering context from a byte array.

Parameters

data:ByteArray — a byte array containing the vertex data. Each data value is four bytes long. The number of values in a vertex is specified at buffer creation using the data32PerVertex parameter to the Context3D createVertexBuffer3D() method. The length of the data in bytes must be byteArrayOffset plus four times the number of values per vertex times the number of vertices. The ByteArray object must use the little endian format.
 
byteArrayOffset:int — number of bytes to skip from the beginning of data
 
startVertex:int — The index of the first vertex to be loaded. A value for startVertex not equal to zero may be used to load a sub-region of the vertex data.
 
numVertices:int — The number of vertices to be loaded from data.

Throws
TypeError — Null Pointer Error: when data is null.
 
RangeError — Bad Input Size: if byteArrayOffset is less than 0, or if byteArrayOffset is greater than or equal to the length of data, or if there isn't enough data in the byte array after the offset position for the number of vertices uploaded.
 
Error — 3768: The Stage3D API may not be used during background execution.

uploadFromVector

()method 
public function uploadFromVector(data:Vector.<Number>, startVertex:int, numVertices:int):void

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 11, AIR 3

Uploads the data for a set of points to the rendering context from a vector array.

Parameters

data:Vector.<Number> — a vector of 32-bit values. A single vertex is comprised of a number of values stored sequentially in the vector. The number of values in a vertex is specified at buffer creation using the data32PerVertex parameter to the Context3D createVertexBuffer3D() method. The length of the vector must be the number of values per vertex times the number of vertexes.
 
startVertex:int — The index of the first vertex to be loaded. A value for startVertex not equal to zero may be used to load a sub-region of the vertex data.
 
numVertices:int — The number of vertices represented by data.

Throws
TypeError — Null Pointer Error: when data is null.
 
RangeError — Bad Input Size: when there isn't enough data in the vector for the number of vertices uploaded.
Context3D_createVertex.as

The following example illustrates how to create and load a vertex data buffer. The buffer in the example contains two types of data for each vertex: the position, as x, y, z coordinates; and the color, as rgb components. After the vertex buffer is created, the example calls the setVertexBufferAt() method to specify that the first three data points are passed to the vertex program as 3 Floating point values in va0 and that the second three data points are passed as va1. A vertex program can have up to 8 inputs, also known as vertex attribute registers, defined in this way.
const dataPerVertex:int = 6;
var vertexData:Vector.<Number> = Vector.<Number>(
    [
      // x, y, z    r, g, b format
         0, 0, 0,   1, 1, 1,
        -1, 1, 0,   0, 0,.5,
         1, 1, 0,   0, 0, 1,
         1,-1, 0,  .5, 0, 0,
        -1,-1, 0,   1, 0, 0
    ]
);
var vertexes:VertexBuffer3D = renderContext.createVertexBuffer( vertexData.length/dataPerVertex, dataPerVertex );
vertexes.uploadFromVector( vertexData, 0, vertexData.length/dataPerVertex );
            
//Identify vertex data inputs for vertex program
renderContext.setVertexBufferAt( 0, vertexes, 0, Context3DVertexBufferFormat.FLOAT_3 ); //Defines shader input va0 as the position data
renderContext.setVertexBufferAt( 1, vertexes, 3, Context3DVertexBufferFormat.FLOAT_3 ); //Defines shader input va1 as the color data