GraphicsDevice.DrawIndexedPrimitives Method

项目
08/15/2012

Renders the specified geometric primitive, based on indexing into an array of vertices.

Syntax

'Declaration
Public Sub DrawIndexedPrimitives ( _
         primitiveType As PrimitiveType, _
         baseVertex As Integer, _
         minVertexIndex As Integer, _
         numVertices As Integer, _
         startIndex As Integer, _
         primitiveCount As Integer _
)

public void DrawIndexedPrimitives (
         PrimitiveType primitiveType,
         int baseVertex,
         int minVertexIndex,
         int numVertices,
         int startIndex,
         int primitiveCount
)

public:
void DrawIndexedPrimitives(
         PrimitiveType primitiveType,
         int baseVertex,
         int minVertexIndex,
         int numVertices,
         int startIndex,
         int primitiveCount
)

Parameters

primitiveType
Type: PrimitiveType
Describes the type of primitive to render. PrimitiveType.PointList is not supported with this method.
baseVertex
Type: Int32
Offset to add to each vertex index in the index buffer.
minVertexIndex
Type: Int32
Minimum vertex index for vertices used during the call. The minVertexIndex parameter and all of the indices in the index stream are relative to the baseVertex parameter.
numVertices
Type: Int32
Number of vertices used during the call. The first vertex is located at index: baseVertex + minVertexIndex.
startIndex
Type: Int32
Location in the index array at which to start reading vertices.
primitiveCount
Type: Int32
Number of primitives to render. The number of vertices used is a function of primitiveCount and primitiveType.

Exceptions

Exception type	Condition
ArgumentOutOfRangeException	primitiveCount is less than or equal to zero. When drawing, at least one primitive must be drawn.
InvalidOperationException	One of the following conditions is true: A valid vertex shader and pixel shader was not set before calling DrawIndexedPrimitives. Both a valid vertex shader and pixel shader (or valid effect) must be set on the device before any draw operations may be performed. Indices is not a valid index buffer. A valid vertex buffer and a valid index buffer must be set on the device before any draw operations may be performed. The active render target and depth stencil surface do not have the same pixel size and multisampling type.
NotSupportedException	The profile does not support an elementSize of IndexElementSize.ThirtyTwoBits; use IndexElementSize.SixteenBits or a type that has a size of two bytes.

ArgumentOutOfRangeException

primitiveCount is less than or equal to zero. When drawing, at least one primitive must be drawn.

InvalidOperationException

One of the following conditions is true:

A valid vertex shader and pixel shader was not set before calling DrawIndexedPrimitives. Both a valid vertex shader and pixel shader (or valid effect) must be set on the device before any draw operations may be performed.
Indices is not a valid index buffer. A valid vertex buffer and a valid index buffer must be set on the device before any draw operations may be performed.
The active render target and depth stencil surface do not have the same pixel size and multisampling type.

NotSupportedException

The profile does not support an elementSize of IndexElementSize.ThirtyTwoBits; use IndexElementSize.SixteenBits or a type that has a size of two bytes.

Example

The vertex buffer and index data of the graphics device must be set before any call to DrawIndexedPrimitives. The following example sets the index data and vertex buffer.

VertexBuffer  vertexBuffer = new VertexBuffer(GraphicsDevice, typeof(VertexPositionColor), 8, BufferUsage.None);

vertexBuffer.SetData<VertexPositionColor>(primitiveList);

IndexBuffer  lineListIndexBuffer = new IndexBuffer(
    GraphicsDevice,
    IndexElementSize.SixteenBits,
    sizeof(short) * lineListIndices.Length,
    BufferUsage.None);

lineListIndexBuffer.SetData<short>(lineListIndices);

GraphicsDevice.Indices = lineListIndexBuffer;
GraphicsDevice.SetVertexBuffer(vertexBuffer);
GraphicsDevice.DrawIndexedPrimitives(PrimitiveType.LineList, 0, 0, 8, 0, 7);

Remarks

This method draws indexed primitives from the current set of data input streams.

The minVertexIndex and numVertices parameters specify the range of vertex indices used for each call to DrawIndexedPrimitives. These vertex indices are used to optimize vertex processing of indexed primitives by processing a sequential range of vertices prior to indexing into them. Indices used during this call cannot reference any vertices outside this range.

If no index array is set, DrawIndexedPrimitives fails.

Requirements

Namespace: Microsoft.Xna.Framework.Graphics

Assembly: Microsoft.Xna.Framework.Graphics (in microsoft.xna.framework.graphics.dll)

Platforms

Windows Phone

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