Matrix.CreateOrthographic Method (Single, Single, Single, Single, Matrix)
Assembly: Microsoft.Xna.Framework (in microsoft.xna.framework.dll)
public static void CreateOrthographic ( float width, float height, float zNearPlane, float zFarPlane, out Matrix result )
Projection space refers to the space after applying projection transformation from view space. After the projection transformation, visible content has x and y coordinates ranging from -1 to 1, and z coordinates ranging from 0 to 1.
Unlike perspective projection, in orthographic projection there is no perspective foreshortening.
The viewable area of this orthographic projection is centered on 0,0,0. The x-axis of the area ranges from -width/2 to width/2. The y-axis of the area ranges from -height/2 to height/2. The z-axis of the area ranges from zNearPlane to zFarPlane. These values are relative to the position and x, y, and z-axes of the view.
To obtain the viewable area (in world space) of a scene, create a BoundingFrustum and pass the combined view and projection matrix to the constructor.