ShareX/GreenshotImageEditor/Drawing/ArrowContainer.cs

/*
 * Greenshot - a free and open source screenshot tool
 * Copyright (C) 2007-2013  Thomas Braun, Jens Klingen, Robin Krom
 *
 * For more information see: http://getgreenshot.org/
 * The Greenshot project is hosted on Sourceforge: http://sourceforge.net/projects/greenshot/
 *
 * 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 1 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; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

using Greenshot.Drawing.Fields;
using Greenshot.Plugin.Drawing;
using System;
using System.Drawing;
using System.Drawing.Drawing2D;

namespace Greenshot.Drawing
{
    /// <summary>
    /// Description of LineContainer.
    /// </summary>
    [Serializable()]
    public class ArrowContainer : LineContainer
    {
        public enum ArrowHeadCombination { NONE, START_POINT, END_POINT, BOTH };

        private static readonly AdjustableArrowCap ARROW_CAP = new AdjustableArrowCap(4, 6);

        public ArrowContainer(Surface parent)
            : base(parent)
        {
            AddField(GetType(), FieldType.ARROWHEADS, 2);
            AddField(GetType(), FieldType.LINE_COLOR, Color.Red);
            //AddField(GetType(), FieldType.FILL_COLOR, Color.Transparent);
            AddField(GetType(), FieldType.SHADOW, true);
            AddField(GetType(), FieldType.ARROWHEADS, ArrowHeadCombination.END_POINT);
        }

        public override void Draw(Graphics graphics, RenderMode rm)
        {
            int lineThickness = GetFieldValueAsInt(FieldType.LINE_THICKNESS);
            bool shadow = GetFieldValueAsBool(FieldType.SHADOW);

            if (lineThickness > 0)
            {
                graphics.SmoothingMode = SmoothingMode.HighQuality;
                graphics.InterpolationMode = InterpolationMode.HighQualityBicubic;
                graphics.CompositingQuality = CompositingQuality.HighQuality;
                graphics.PixelOffsetMode = PixelOffsetMode.None;
                Color lineColor = GetFieldValueAsColor(FieldType.LINE_COLOR);
                ArrowHeadCombination heads = (ArrowHeadCombination)GetFieldValue(FieldType.ARROWHEADS);
                if (lineThickness > 0)
                {
                    if (shadow)
                    {
                        //draw shadow first
                        int basealpha = 100;
                        int alpha = basealpha;
                        int steps = 5;
                        int currentStep = 1;
                        while (currentStep <= steps)
                        {
                            using (Pen shadowCapPen = new Pen(Color.FromArgb(alpha, 100, 100, 100), lineThickness))
                            {
                                SetArrowHeads(heads, shadowCapPen);

                                graphics.DrawLine(shadowCapPen,
                                    Left + currentStep,
                                    Top + currentStep,
                                    Left + currentStep + Width,
                                    Top + currentStep + Height);

                                currentStep++;
                                alpha = alpha - (basealpha / steps);
                            }
                        }
                    }
                    using (Pen pen = new Pen(lineColor, lineThickness))
                    {
                        SetArrowHeads(heads, pen);
                        graphics.DrawLine(pen, Left, Top, Left + Width, Top + Height);
                    }
                }
            }
        }

        private void SetArrowHeads(ArrowHeadCombination heads, Pen pen)
        {
            if (heads == ArrowHeadCombination.BOTH || heads == ArrowHeadCombination.START_POINT)
            {
                pen.CustomStartCap = ARROW_CAP;
            }
            if (heads == ArrowHeadCombination.BOTH || heads == ArrowHeadCombination.END_POINT)
            {
                pen.CustomEndCap = ARROW_CAP;
            }
        }

        public override Rectangle DrawingBounds
        {
            get
            {
                int lineThickness = GetFieldValueAsInt(FieldType.LINE_THICKNESS);
                if (lineThickness > 0)
                {
                    using (Pen pen = new Pen(Color.White))
                    {
                        pen.Width = lineThickness;
                        SetArrowHeads((ArrowHeadCombination)GetFieldValue(FieldType.ARROWHEADS), pen);
                        using (GraphicsPath path = new GraphicsPath())
                        {
                            path.AddLine(Left, Top, Left + Width, Top + Height);
                            Rectangle drawingBounds = Rectangle.Round(path.GetBounds(new Matrix(), pen));
                            drawingBounds.Inflate(2, 2);
                            return drawingBounds;
                        }
                    }
                }
                else
                {
                    return Rectangle.Empty;
                }
            }
        }

        public override bool ClickableAt(int x, int y)
        {
            int lineThickness = GetFieldValueAsInt(FieldType.LINE_THICKNESS) + 10;
            if (lineThickness > 0)
            {
                using (Pen pen = new Pen(Color.White))
                {
                    pen.Width = lineThickness;
                    SetArrowHeads((ArrowHeadCombination)GetFieldValue(FieldType.ARROWHEADS), pen);
                    using (GraphicsPath path = new GraphicsPath())
                    {
                        path.AddLine(Left, Top, Left + Width, Top + Height);
                        return path.IsOutlineVisible(x, y, pen);
                    }
                }
            }
            else
            {
                return false;
            }
        }
    }
}