//// This code is part of Document Solutions for Imaging demos.// Copyright (c) MESCIUS inc. All rights reserved.//using System;using System.Drawing;using GrapeCity.Documents.Imaging;using GrapeCity.Documents.Text;using GrapeCity.Documents.Drawing;
namespace DsImagingWeb.Demos{    // Sample shows how to create gradient fills using LinearGradientBrush and RadialGradientBrush.    public class Gradients    {        public GcBitmap GenerateImage(Size pixelSize, float dpi, bool opaque, string[] sampleParams = null)        {            var bmp = new GcBitmap(pixelSize.Width, pixelSize.Height, true, dpi, dpi);            var Inch = dpi;            using (var g = bmp.CreateGraphics(Color.RoyalBlue))            {                var testRectSize = new SizeF(Inch * 6, Inch);                var dy = Inch / 6;                // TextLayout to draw labels:                var tl = g.CreateTextLayout();                tl.DefaultFormat.FontSize = Inch / 6;                tl.DefaultFormat.ForeColor = Color.Chartreuse;                tl.MaxWidth = testRectSize.Width;                tl.MaxHeight = testRectSize.Height;                tl.TextAlignment = TextAlignment.Center;                tl.ParagraphAlignment = ParagraphAlignment.Center;                // Note 1:                var rc = Common.Util.AddNote("Linear gradients using LinearGradientBrush:", g, new RectangleF(Inch, Inch / 2, 500, 100));                // Text insertion point:                PointF ip = new PointF(rc.Left, rc.Bottom + dy);                // Local action to draw a gradient-filled rectangle:                Action<GrapeCity.Documents.Drawing.Brush, string> drawSwatch = (b_, txt_) =>                {                    var rect = new RectangleF(ip, testRectSize);                    // Fill the rectangle with a gradient brush:                    g.FillRectangle(rect, b_);                    // Draw a border, text info etc:                    g.DrawRectangle(rect, Color.Magenta);                    tl.Clear();                    tl.Append(txt_);                    tl.MaxHeight = testRectSize.Height;                    tl.MaxWidth = testRectSize.Width;                    tl.PerformLayout(true);                    g.DrawTextLayout(tl, ip);                    ip.Y += rect.Height + dy;                };                // LinearGradientBrush:                // Horizontal gradient:                LinearGradientBrush linearGradBrush = new LinearGradientBrush(Color.Red, Color.Blue);                drawSwatch(linearGradBrush, $"Linear gradient\nfrom {linearGradBrush.StartPoint} to {linearGradBrush.EndPoint}");                // Vertical gradient:                linearGradBrush = new LinearGradientBrush(Color.Red, new PointF(0, 0), Color.Green, new PointF(0, 1));                drawSwatch(linearGradBrush, $"Linear gradient\r\nfrom {linearGradBrush.StartPoint} to {linearGradBrush.EndPoint}");                // Diagonal gradient (increase swatch height to better show diagonal):                testRectSize.Height *= 2;                linearGradBrush = new LinearGradientBrush(Color.Red, new PointF(0, 0), Color.Teal, new PointF(1, 1));                drawSwatch(linearGradBrush, $"Linear gradient\r\nfrom {linearGradBrush.StartPoint} to {linearGradBrush.EndPoint}");                // RadialGradientBrush                rc = Common.Util.AddNote("Radial gradients using RadialGradientBrush:", g, new RectangleF(ip, new SizeF(500, 100)));                ip.Y = rc.Bottom + dy;                // Centered:                // testRectSize.Height *= 2;                RadialGradientBrush radialGradBrush = new RadialGradientBrush(Color.Orange, Color.Purple);                drawSwatch(radialGradBrush, $"Radial gradient\r\nwith origin at {radialGradBrush.GradientOrigin}");                // Center in bottom right corner:                radialGradBrush = new RadialGradientBrush(Color.OrangeRed, Color.DarkBlue, new PointF(1, 1));                drawSwatch(radialGradBrush, $"Radial gradient\r\nwith origin at {radialGradBrush.GradientOrigin}");            }            // Done:            return bmp;        }    }}