RoundRectangle.cs
//
// This code is part of GrapeCity Documents for Imaging samples.
// Copyright (c) GrapeCity, Inc. All rights reserved.
//
using System;
using System.IO;
using System.Drawing;
using GrapeCity.Documents.Imaging;
using GrapeCity.Documents.Text;
using GrapeCity.Documents.Drawing;

namespace GcImagingWeb.Samples
{
    // This sample demonstrates how to draw round rectangles
    // using dedicated DrawRoundRect/FillRoundRect methods.
    // It also shows how the same result may be achieved with
    // graphics paths.
    public class RoundRectangle
    {
        public GcBitmap GenerateImage(int pixelWidth = 1024, int pixelHeight = 1024, bool opaque = true, float dpiX = 96, float dpiY = 96)
        {
            var bmp = new GcBitmap(pixelWidth, pixelHeight, true, dpiX, dpiY);
            var Inch = dpiX;
            using (var g = bmp.CreateGraphics(Color.RoyalBlue))
            {
                var rc = Common.Util.AddNote(
                "GcGraphics has dedicated methods to easily draw and fill rectangles with rounded corners. " +
                "This sample also shows how the same result may be achieved using graphics paths. " +
                "While they are not really needed for drawing round rectangles, graphics paths allow " +
                "to draw and fill arbitrary figures with complex geometries.",
                g);

                // Rounded rectangle's radii:
                float rx = 36, ry = 24;

                // Using dedicated methods to draw and fill round rectangles:
                var rEasy = new RectangleF(rc.Left, rc.Bottom + Inch / 2, Inch * 2, Inch);
                g.FillRoundRect(rEasy, rx, ry, Color.PaleGreen);
                g.DrawRoundRect(rEasy, rx, ry, Color.Blue, 4);
                // Add a label:
                var tf = new TextFormat()
                {
                    Font = Font.FromFile(Path.Combine("Resources", "Fonts", "times.ttf")),
                    FontSize = Inch / 6
                };
                g.DrawString("The easy way.", tf, rEasy, TextAlignment.Center, ParagraphAlignment.Center, false);

                // Using graphics path to achieve the same result:
                var rHard = rEasy;
                rHard.Offset(0, rEasy.Height + Inch / 2);
                var path = MakeRoundRect(g, rHard, rx, ry);
                g.FillPath(path, Color.PaleVioletRed);
                g.DrawPath(path, Color.Purple, 4);
                // Add a label:
                g.DrawString("The hard way.", tf, rHard, TextAlignment.Center, ParagraphAlignment.Center, false);

                // Done:
            }
            // Done:
            return bmp;
        }

        // This method shows how to create a graphics path that may be used
        // to fill or draw arbitrary shapes on a GcGraphics.
        private IPath MakeRoundRect(GcGraphics g, RectangleF rc, float rx, float ry)
        {
            var path = g.CreatePath();
            var sz = new SizeF(rx, ry);
            // start from horizontal top left
            path.BeginFigure(new PointF(rc.Left + rx, rc.Top));
            path.AddLine(new PointF(rc.Right - rx, rc.Top));
            path.AddArc(new ArcSegment() { Point = new PointF(rc.Right, rc.Top + ry), SweepDirection = SweepDirection.Clockwise, Size = sz });
            path.AddLine(new PointF(rc.Right, rc.Bottom - ry));
            path.AddArc(new ArcSegment() { Point = new PointF(rc.Right - rx, rc.Bottom), SweepDirection = SweepDirection.Clockwise, Size = sz });
            path.AddLine(new PointF(rc.Left + rx, rc.Bottom));
            path.AddArc(new ArcSegment() { Point = new PointF(rc.Left, rc.Bottom - ry), SweepDirection = SweepDirection.Clockwise, Size = sz });
            path.AddLine(new PointF(rc.Left, rc.Top + ry));
            path.AddArc(new ArcSegment() { Point = new PointF(rc.Left + rx, rc.Top), SweepDirection = SweepDirection.Clockwise, Size = sz });
            path.EndFigure(FigureEnd.Closed);
            return path;
        }
    }
}