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GraphicsDevice.DrawUserPrimitives Generic Method

Renders the given geometric primitive with data specified by the user.

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

Syntax

public void DrawUserPrimitives<T> (
         PrimitiveType primitiveType,
         T[] vertexData,
         int vertexOffset,
         int primitiveCount
) where T : ValueType

Type Parameters

  • T

Parameters

  • primitiveType
    Describes the type of primitive to render.
  • vertexData
    The vertex data.
  • vertexOffset
    Offset at which to begin reading vertexData.
  • primitiveCount
    Number of primitives to render. The maximum number of primitives allowed is determined by checking MaxPrimitiveCount. The number of indices is a function of primitiveCount and primitiveType.

Exceptions

Exception type Condition
ArgumentException vertexOffset + numVertices is outside of the range of vertexData.
ArgumentNullException vertexData is null.
ArgumentOutOfRangeException

One of the following conditions is true:

  • primitiveCount is less than or equal to zero. When drawing, at least one primitive must be drawn.
  • vertexOffset is less than zero or greater than the length of vertexData.
InvalidOperationException

One of the following conditions is true:

  • VertexDeclaration is not a valid value. A valid vertex declaration must be set on the device before any draw operations can be performed.
  • A valid vertex shader and pixel shader was not set before calling DrawUserPrimitives. Both a valid vertex shader and pixel shader (or valid effect) must be set on the device before any draw operations may be performed. See How to: Use BasicEffect or How to: Create and Apply Custom Effects for more information on applying effects.
  • vertexData is not a valid vertex buffer. A valid vertex buffer must be set on the device before any draw operations may be performed.

Remarks

This method is intended for use when drawing dynamic geometry specified by the user. It supports only a single vertex stream. The effect of this call is to use the provided vertex data pointer and stride for vertex stream 0. It is invalid to have the declaration of the current vertex shader refer to vertex streams other than stream 0.

The vertex data passed to DrawUserPrimitives does not need to persist after the call. Access to the data is completed before returning from the call.

See Also

Tasks

How to: Draw Point Sprites

Reference

GraphicsDevice Class
GraphicsDevice Members
Microsoft.Xna.Framework.Graphics Namespace

Platforms

Xbox 360, Windows XP SP2, Windows Vista