Matrix Structure (Microsoft.DirectX)

How Do I...?

• Set Up a Projection Matrix

Describes and manipulates a matrix.

Definition

Visual Basic	Public Structure Matrix
C#	public struct Matrix
C++	public value class Matrix sealed
JScript	In JScript, you can use structures, but you cannot define your own.

Members Table

The following table lists the members exposed by the object.

Fields

Field	Description
M11	Retrieves or sets the element in the first row and the first column of the matrix.
M12	Retrieves or sets the element in the first row and the second column of the matrix.
M13	Retrieves or sets the element in the first row and the third column of the matrix.
M14	Retrieves or sets the element in the first row and the fourth column of the matrix.
M21	Retrieves or sets the element in the second row and the first column of the matrix.
M22	Retrieves or sets the element in the second row and the second column of the matrix.
M23	Retrieves or sets the element in the second row and the third column of the matrix.
M24	Retrieves or sets the element in the second row and the fourth column of the matrix.
M31	Retrieves or sets the element in the third row and the first column of the matrix.
M32	Retrieves or sets the element in the third row and the second column of the matrix.
M33	Retrieves or sets the element in the third row and the third column of the matrix.
M34	Retrieves or sets the element in the third row and the fourth column of the matrix.
M41	Retrieves or sets the element in the fourth row and the first column of the matrix.
M42	Retrieves or sets the element in the fourth row and the second column of the matrix.
M43	Retrieves or sets the element in the fourth row and the third column of the matrix.
M44	Retrieves or sets the element in the fourth row and the fourth column of the matrix.

Methods

Method	Description
Add	Adds two matrices.
AffineTransformation	Builds a 3-D affine transformation matrix.
AffineTransformation2D	Builds a 2-D affine transformation matrix in the xy plane.
Equals	Returns a value that indicates whether the current instance is equal to a specified object.
GetHashCode	Returns the hash code for the current instance.
Invert	Calculates the inverse of a matrix.
LookAtLH	Builds a left-handed look-at matrix.
LookAtRH	Builds a right-handed look-at matrix.
Matrix	Initializes a new instance of the Matrix class.
Multiply	Determines the product of two matrices.
MultiplyTranspose	Calculates the transposed product of two matrices.
op_Addition	Adds two instances of the Matrix structure.
op_Equality	Compares the current instance of a class to another instance to determine whether they are the same.
op_Inequality	Compares the current instance of a class to another instance to determine whether they are different.
op_Multiply	Determines the product of two matrices.
op_Subtraction	Subtracts two instances of the Matrix structure.
OrthoLH	Builds a left-handed orthogonal projection matrix.
OrthoOffCenterLH	Builds a customized, left-handed orthogonal projection matrix.
OrthoOffCenterRH	Builds a customized, right-handed orthogonal projection matrix.
OrthoRH	Builds a right-handed orthogonal projection matrix.
PerspectiveFovLH	Builds a left-handed perspective projection matrix based on a field of view.
PerspectiveFovRH	Builds a right-handed perspective projection matrix based on a field of view (FOV).
PerspectiveLH	Builds a left-handed perspective projection matrix.
PerspectiveOffCenterLH	Builds a customized, left-handed perspective projection matrix.
PerspectiveOffCenterRH	Builds a customized, right-handed perspective projection matrix.
PerspectiveRH	Builds a right-handed perspective projection matrix.
Reflect	Builds a matrix that reflects the coordinate system about a plane.
RotateAxis	Rotates the matrix around an arbitrary axis.
RotateQuaternion	Rotates a matrix from a quaternion.
RotateX	Rotates a matrix around the x-axis.
RotateY	Rotates a matrix around the y-axis.
RotateYawPitchRoll	Rotates a matrix with a specified yaw, pitch, and roll.
RotateZ	Rotates the matrix around the z-axis.
RotationAxis	Builds a matrix that rotates around an arbitrary axis.
RotationQuaternion	Builds a matrix from a quaternion.
RotationX	Builds a matrix that rotates around the x-axis.
RotationY	Builds a matrix that rotates around the y-axis.
RotationYawPitchRoll	Builds a matrix with a specified yaw, pitch, and roll.
RotationZ	Builds a matrix that rotates around the z-axis.
Scale	Scales the matrix along the x-axis, y-axis, and z-axis.
Scaling	Builds a matrix that scales along the x-axis, y-axis, and z-axis.
Shadow	Builds a matrix that flattens geometry into a plane.
Subtract	Subtracts one matrix from another.
ToString	Obtains a string representation of the current instance.
Transform	Transforms the matrix.
Transformation	Builds a transformation matrix.
Transformation2D	Builds a 2-D transformation matrix in the xy plane.
Translate	Translates the matrix using specified offsets.
Translation	Builds a matrix using specified offsets.
Transpose	Transposes the matrix using a source matrix.
TransposeMatrix	Returns the matrix transpose of a given matrix.

Properties

Property	Description
Determinant	Retrieves the determinant of the matrix.
Identity	Retrieves the identity of the matrix.
Zero	Retrieves an empty matrix.

Remarks

This structure represents a 4x4 matrix of Single values. The fields of this structure are named with the row number first, then the column number.

In Microsoft Direct3D, the M34 element of a projection matrix cannot be a negative number. If an application needs to use a negative value in this location, it should scale the entire projection matrix by -1 instead.

How Do I...?

Set Up a Projection Matrix

This example demonstrates how to set up the projection transformation matrix, which transforms 3-D camera or view space coordinates into 2-D screen coordinates.

See the following C# code example, the Projection transformation matrix is set to be equal to the left-handed (LH) PerspectiveFovLH matrix. Input arguments to PerspectiveFovLH are as follows.

1. Field of view in radians: pi/4.
2. Aspect ratio, or view-space height divided by width: 1, for a square window.
3. Near clipping plane distance: 1 unit.
4. Far clipping plane distance: 100 units.

              [C#]
              

using Microsoft.DirectX;

Direct3D.Device device = null;  // Create rendering device.

// For the projection matrix, you set up a perspective transform (which
//   transforms geometry from 3-D view space to 2-D viewport space, with
//   a perspective divide making objects smaller in the distance). To build
//   a perspective transform, you need the field of view (1/4 pi is common),
//   the aspect ratio, and the near and far clipping planes (which define 
//   the distances at which geometry should no longer be rendered).

device.Transform.Projection = Matrix.PerspectiveFovLH(
                              (float)Math.PI / 4, 1.0f, 1.0f, 100.0f );

Structure Information

Namespace	Microsoft.DirectX
Assembly	Microsoft.DirectX (microsoft.directx.dll)
Strong Name	Microsoft.DirectX,  Version=1.0.900.0,  Culture=neutral,  PublicKeyToken=d3231b57b74a1492

See Also

• Device.GetTransform
• Device.SetTransform
• Device.SetTransform
• Microsoft.DirectX.UnsafeNativeMethods.Matrix Class