ImageGear v26.5 - Updated
ImageGear.Formats.Pdf Assembly / ImageGear.Formats.PDF Namespace / ImGearPDFFixedMatrix Class
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    ImGearPDFFixedMatrix Class
    In This Topic
    Describes a matrix containing fixed numbers.
    Object Model
    ImGearPDFFixedMatrix Class
    Syntax
    'Declaration
     
    Public NotInheritable Class ImGearPDFFixedMatrix 
    'Usage
     
    Dim instance As ImGearPDFFixedMatrix
    public sealed class ImGearPDFFixedMatrix 
    public __gc __sealed class ImGearPDFFixedMatrix 
    public ref class ImGearPDFFixedMatrix sealed 
    Remarks
    This class defines a transformation matrix for the content object, which usually corresponds to the Matrix key in the dictionary. A transformation matrix specifies the relationship between two coordinate systems. By modifying a transformation matrix, objects can be scaled, rotated, translated, or transformed in other ways. The transformation between two coordinate systems is represented by a 3-by-3 transformation matrix written as follows:

    A B 0

    C D 0

    H V 1

    A transformation matrix has only six elements that can be changed as the six-element array [ a b c d h v ]. It can represent any linear transformation from one coordinate system to another. The transformation matrix multiplication can be presented as follows:

    x1 = x*A + y*C + H

    y1 = x*B + y* D + V

    The following lists the arrays that specify the most common transformations:

    • Translations are specified as [ 1 0 0 1 tx ty ], where tx and ty are the distances to translate the origin of the coordinate system in the horizontal and vertical dimensions, respectively.
    • Scaling is obtained by [ sx 0 0 sy 0 0 ]. This scales the coordinates so that 1 unit in the horizontal and vertical dimensions of the new coordinate system is the same size as sx and sy units, respectively, in the previous coordinate system.
    • Rotations are produced by [ cos Ang sin Ang -sin Ang cos Ang 0 0 ], which has the effect of rotating the coordinate system axes by an angle Ang counterclockwise.
    • Skew is specified by [ 1 tan a tan b 1 0 0 ], which skews the x axis by an angle a and the y axis by an angle b.

    If several transformations are combined, the order in which they are applied is significant. For example, first scaling and then translating the x axis is not the same as first translating and then scaling it.

    In general, to obtain the expected results, transformations should be done in the following order:

    Translate

    RotateScale or skew

    See section "4.2 Coordinate Systems" of the PDF Reference for more details.

    Inheritance Hierarchy

    System.Object
       ImageGear.Formats.PDF.ImGearPDFFixedMatrix

    See Also