#region Using directives

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Text;
using System.Windows.Forms;

#endregion

namespace TransformsSample {
  partial class MatrixMarginsForm : Form {
    public MatrixMarginsForm() {
      InitializeComponent();
    }

    string s = "For example, it’s not important that the ruler at the top of the document I’m typing this sentence into is currently showing an inch as 1 9/16 inches. What is important is the proportion of the dimensions of each line in proportion to the units shown as “inches” as compared to the width and height of each line as I type. The principle of WYSIWYG (What You See Is What You Get) says that I should be able to print something very similar to what I’m seeing on the screen . When my word processing program shows a line wrapping at a certain word when I get close to the 6 ½ inches area inside of my margins (my page settings are set to standard 8 ½ inch wide paper with a 1 inch margin on each side), I want that same wrap to happen at the same word when I print. To make that happen, we need to be able to write a program that can wrap text at units other than pixels, as shown in Figure 1.";

    private void MatrixMarginsForm_Load(object sender, EventArgs e) {
      ShowClientSize();
    }

    private void MatrixMarginsForm_Paint(object sender, PaintEventArgs e) {
      PaintInInches(e.Graphics);
    }

    private void MatrixMarginsForm_Resize(object sender, EventArgs e) {
      ShowClientSize();
    }

    private float InchesToPixels(float inches) {
      using( Graphics g = this.CreateGraphics() ) {
        return inches * g.DpiY;
      }
    }

    private RectangleF InchesToPixels(RectangleF rect) {
      return new RectangleF(InchesToPixels(rect.X), InchesToPixels(rect.Y), InchesToPixels(rect.Width), InchesToPixels(rect.Height));
    }

    private float PixelsToInches(float pixels) {
      using( Graphics g = this.CreateGraphics() ) {
        return pixels / g.DpiY;
      }
    }

    private void PaintInInches(Graphics g) {
      // Set units to inches using a transform
      Matrix matrix = new Matrix();
      matrix.Scale(g.DpiX, g.DpiY);
      g.Transform = matrix;

      using( Font rulerFont = new Font("MS Sans Serif", 8.25f / g.DpiY) )
      using( Pen blackPen = new Pen(Color.Black, 0) ) {
        float rulerFontHeight = rulerFont.GetHeight(g); // Inches
        // Specifiy units in inches
        RectangleF rulerRect =
          new RectangleF(
          0, 0,
          6.5f, rulerFontHeight * 1.5f);
        // Draw in inches
        g.DrawRectangle(
          blackPen,
          rulerRect.X, rulerRect.Y,
          rulerRect.Width, rulerRect.Height);

        // Draw 6.5 inches in inches
        for( float i = 1; i <= 6; ++i ) {
          // Specify units in inches
          RectangleF rect = new RectangleF(i - rulerFontHeight, 0, rulerFontHeight * 2, rulerFontHeight);
          StringFormat format = new StringFormat();
          format.Alignment = StringAlignment.Center;
          g.DrawString(i.ToString(), rulerFont, Brushes.Black, rect, format);
          //g.DrawLine(blackPen, i, 0, i, rulerFontHeight/2);
        }

        // Draw 6.5 inches in half inches
        for( float i = 0.5f; i <= 6.5f; i += 1.0f ) {
          g.DrawLine(blackPen, i, 0, i, rulerFontHeight / 2);
        }

        using( Font textFont = new Font("Times New Roman", 11f / g.DpiY) ) {
          // Draw text wrapped to 6.5 inch margin
          RectangleF textRect = new RectangleF(0, rulerRect.Height, 6.5f, PixelsToInches(this.ClientRectangle.Height) - rulerRect.Height);
          g.FillRectangle(Brushes.White, textRect);
          g.DrawRectangle(blackPen, textRect.X, textRect.Y, textRect.Width, textRect.Height);
          g.DrawString(s, textFont, Brushes.Black, textRect);
        }
      }
    }

    private void ShowClientSize() {
      using( Graphics g = this.CreateGraphics() ) {
        // Set units to inches using a transform
        Matrix matrix = new Matrix();
        matrix.Scale(g.DpiX, g.DpiY);
        g.Transform = matrix;

        PointF[] bottomRight =
          new PointF[] { new PointF(this.ClientSize.Width, this.ClientSize.Height) };
        // Convert client size from pixels to inches
        g.TransformPoints(
          CoordinateSpace.World, CoordinateSpace.Device, bottomRight);
        this.toolStripStatusLabel1.Text = string.Format("ClientSize= {0} pixels, {1} inches", this.ClientSize, bottomRight[0]);
      }
    }
  }
}