Options to use with RenderRedirect to re-direct the rendering of the content of the viewer to an external context.
public class ImageViewerRenderRedirectOptions
public ref class ImageViewerRenderRedirectOptions
For more information, refer to RenderRedirect and Image Viewer Rendering.
using Leadtools;
using Leadtools.Controls;
using Leadtools.Codecs;
using Leadtools.Drawing;
using Leadtools.ImageProcessing;
using Leadtools.ImageProcessing.Color;
public ImageViewerForm _form = new ImageViewerForm();
public ImageViewer _imageViewer;
public PictureBox redirectRenderControl;
public void ImageViewerRedirectRenderExample()
{
// Get the ImageViewer control from the form
_imageViewer = _form.ImageViewer;
// Load an image
using (var codecs = new RasterCodecs())
_imageViewer.Image = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "cannon.jpg"));
// PanZoom Interactive Mode
_imageViewer.DefaultInteractiveMode = new ImageViewerPanZoomInteractiveMode();
// Separate Form with PictureBox control
Form redirectRenderForm = new Form();
redirectRenderControl = new PictureBox();
redirectRenderControl.Width = 400;
redirectRenderControl.Dock = DockStyle.Fill;
redirectRenderForm.Controls.Add(redirectRenderControl);
redirectRenderForm.Show();
// Invalidate on double-click
bool renderView = false;
redirectRenderControl.DoubleClick += (sender, e) =>
{
renderView = !renderView;
redirectRenderControl.Invalidate();
};
redirectRenderControl.Paint += (sender, e) =>
{
if (_imageViewer.Image == null)
return;
// Get PictureBox Graphics object
Graphics graphics = e.Graphics;
// Destination rectangle in PictureBox
int margin = 20;
LeadRect destRect = LeadRect.Create(margin, margin, redirectRenderControl.ClientSize.Width - margin * 2, redirectRenderControl.ClientSize.Height - margin * 2);
LeadRect clipRect = destRect;
// Source rectangle
Debug.WriteLine(_imageViewer.ViewSize);
// RenderRedirect Options
ImageViewerRenderRedirectOptions options = new ImageViewerRenderRedirectOptions();
options.BackgroundColor = Color.Transparent;
// Try to get item from the viewer
ImageViewerItem item = null;
if (!renderView)
item = _imageViewer.Items[0];
LeadRectD sourceRect = LeadRectD.Empty;
if (item == null)
sourceRect = _imageViewer.GetViewBounds(true, false);
else
{
sourceRect = _imageViewer.GetItemViewBounds(item, ImageViewerItemPart.Image, false);
options.RenderBackgrounds = false;
options.RenderBorders = false;
options.RenderItemStates = false;
options.RenderShadows = false;
options.RenderText = false;
}
// Transformation Matrix (represents rotation, zooming...etc)
Debug.WriteLine(_imageViewer.ViewTransform);
options.CreateTransform(_imageViewer, destRect, sourceRect, ControlSizeMode.FitAlways, ControlAlignment.Center, ControlAlignment.Center);
clipRect = options.Transform.TransformRect(sourceRect).ToLeadRect();
// Redirect rendering to the PictureBox Graphics object (Outlined with a black rectangle)
_imageViewer.RenderRedirect(graphics, options, clipRect);
graphics.DrawRectangle(Pens.Black, destRect.X, destRect.Y, destRect.Width + 1, destRect.Height + 1);
// Calculate visible view
LeadRectD rect;
if (item == null)
rect = _imageViewer.GetViewBounds(true, true);
else
rect = _imageViewer.GetItemViewBounds(item, ImageViewerItemPart.Image, true);
LeadPointD[] points =
{
LeadPointD.Create(rect.Left, rect.Top),
LeadPointD.Create(rect.Right, rect.Bottom)
};
options.Transform.TransformPoints(points);
double xmin = points[0].X;
double ymin = points[0].Y;
double xmax = xmin;
double ymax = ymin;
for (int i = 1; i < points.Length; i++)
{
if (points[i].X < xmin) xmin = points[i].X;
if (points[i].X > xmax) xmax = points[i].X;
if (points[i].Y < ymin) ymin = points[i].Y;
if (points[i].Y > ymax) ymax = points[i].Y;
}
// Draw yellow rectangle showing visible part of the view
LeadRectD bounds = LeadRectD.FromLTRB(xmin, ymin, xmax, ymax);
RectangleF rc = new RectangleF((float)bounds.X, (float)bounds.Y, (float)bounds.Width, (float)bounds.Height);
graphics.DrawRectangle(Pens.Yellow, rc.X, rc.Y, rc.Width - 1, rc.Height - 1);
};
_imageViewer.RedirectRender += (sender, e) =>
{
redirectRenderControl.Invalidate();
};
}
static class LEAD_VARS
{
public const string ImagesDir = @"C:\LEADTOOLS23\Resources\Images";
}
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