ModifyCTM.cs :  » PDF » PDF-Clown » it » stefanochizzolini » clown » documents » contents » objects » C# / CSharp Open Source

/*
  Copyright 2007 Stefano Chizzolini. http://clown.stefanochizzolini.it

  Contributors:
    * Stefano Chizzolini (original code developer, http://www.stefanochizzolini.it)

  This file should be part of the source code distribution of "PDF Clown library"
  (the Program): see the accompanying README files for more info.

  This Program is free software; you can redistribute it and/or modify it under
  the terms of the GNU General Public License as published by the Free Software
  Foundation; either version 2 of the License, or (at your option) any later version.

  This Program is distributed in the hope that it will be useful, but WITHOUT ANY
  WARRANTY, either expressed or implied; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the License for more details.

  You should have received a copy of the GNU General Public License along with this
  Program (see README files); if not, go to the GNU website (http://www.gnu.org/).

  Redistribution and use, with or without modification, are permitted provided that such
  redistributions retain the above copyright notice, license and disclaimer, along with
  this list of conditions.
*/

using it.stefanochizzolini.clown.bytes;
using it.stefanochizzolini.clown.objects;

using System.Collections.Generic;
using System.Drawing.Drawing2D;

namespace it.stefanochizzolini.clown.documents.contents.objects{
  /**
    <summary>'Modify the current transformation matrix (CTM) by concatenating the specified matrix'
    operation [PDF:1.6:4.3.3].</summary>
  */
  public sealed class ModifyCTM
    : Operation
  {
    #region static
    #region fields
    public static readonly string OperatorKeyword = "cm";
    #endregion

    #region interface
    #region public
    public static ModifyCTM GetResetCTM(
      double[] ctm
      )
    {
      Matrix matrix = new Matrix((float)ctm[0],(float)ctm[1],(float)ctm[2],(float)ctm[3],(float)ctm[4],(float)ctm[5]);
      matrix.Invert();
      float[] inverseMatrixData = matrix.Elements;

      return new ModifyCTM(
        inverseMatrixData[0],
        inverseMatrixData[1],
        inverseMatrixData[2],
        inverseMatrixData[3],
        inverseMatrixData[4],
        inverseMatrixData[5]
        );
    }
    #endregion
    #endregion
    #endregion

    #region dynamic
    #region constructors
    public ModifyCTM(
      double a,
      double b,
      double c,
      double d,
      double e,
      double f
      ) : base(
        OperatorKeyword,
        new List<PdfDirectObject>(
          new PdfDirectObject[]
          {
            new PdfReal(a),
            new PdfReal(b),
            new PdfReal(c),
            new PdfReal(d),
            new PdfReal(e),
            new PdfReal(f)
          }
          )
        )
    {}

    public ModifyCTM(
      List<PdfDirectObject> operands
      ) : base(OperatorKeyword,operands)
    {}
    #endregion

    #region interface
    #region public
    /**
      <summary>Applies the transformation to the specified transformation matrix
      by concatenation.</summary>
      <param name="ctm">Current Transformation Matrix.</param>
      <returns>Transformed transformation matrix.</returns>
    */
    public double[] ApplyTo(
      double[] ctm
      )
    {
      // Get the new transformation matrix!
      double[] ntm = GetMatrix();
      // Initialize the resulting transformation matrix!
      double[] rtm = new double[6];
      // Apply the transformation to the existing transformation matrix!
      rtm[0] = ntm[0]*ctm[0] + ntm[1]*ctm[2]; // a.
      rtm[1] = ntm[0]*ctm[1] + ntm[1]*ctm[3]; // b.
      rtm[2] = ntm[2]*ctm[0] + ntm[3]*ctm[2]; // c.
      rtm[3] = ntm[2]*ctm[1] + ntm[3]*ctm[3]; // d.
      rtm[4] = ntm[4]*ctm[0] + ntm[5]*ctm[2] + 1*ctm[4]; // e.
      rtm[5] = ntm[4]*ctm[1] + ntm[5]*ctm[3] + 1*ctm[5]; // f.

      return rtm;
    }

    public double[] GetMatrix(
      )
    {
      return new double[]
        {
          ((IPdfNumber)operands[0]).RawValue, // a.
          ((IPdfNumber)operands[1]).RawValue, // b.
          ((IPdfNumber)operands[2]).RawValue, // c.
          ((IPdfNumber)operands[3]).RawValue, // d.
          ((IPdfNumber)operands[4]).RawValue, // e.
          ((IPdfNumber)operands[5]).RawValue // f.
        };
    }
    #endregion
    #endregion
    #endregion
  }
}