PaintOverlay(RasterImage,Graphics,Int32,LeadRect,LeadRect,LeadRect,LeadRect,RasterPaintProperties) Method

Paints the overlay at the specified index. Use this method to paint overlays that are not automatically painted.

Syntax

C#
Visual Basic
Objective-C
Java
C++

public static void PaintOverlay( 
   RasterImage image,
   Graphics graphics,
   int index,
   LeadRect srcRect,
   LeadRect srcClipRect,
   LeadRect destRect,
   LeadRect destClipRect,
   RasterPaintProperties properties
)

'Declaration

Public Overloads Shared Sub PaintOverlay( _
   ByVal image As RasterImage, _
   ByVal graphics As Graphics, _
   ByVal index As Integer, _
   ByVal srcRect As LeadRect, _
   ByVal srcClipRect As LeadRect, _
   ByVal destRect As LeadRect, _
   ByVal destClipRect As LeadRect, _
   ByVal properties As RasterPaintProperties _
)

'Usage

Dim image As RasterImage
Dim graphics As Graphics
Dim index As Integer
Dim srcRect As LeadRect
Dim srcClipRect As LeadRect
Dim destRect As LeadRect
Dim destClipRect As LeadRect
Dim properties As RasterPaintProperties
 
RasterImagePainter.PaintOverlay(image, graphics, index, srcRect, srcClipRect, destRect, destClipRect, properties)

public:
static void PaintOverlay( 
   RasterImage^ image,
   Graphics^ graphics,
   int index,
   LeadRect srcRect,
   LeadRect srcClipRect,
   LeadRect destRect,
   LeadRect destClipRect,
   RasterPaintProperties properties
)

Parameters

image: The source image.
graphics: The destination graphics object where the image will be displayed.
index: The index of the overlay used for painting. The overlay should have an image. If the overlay is embedded into an image bitplane, make sure you create an overlay image prior to calling this method. This index is zero-based.
srcRect: Rectangle which determines the portion of the image to paint.
srcClipRect: Rectangle which further clips the source image.
destRect: Rectangle which determines where the image is placed, and how it is scaled.
destClipRect: Rectangle which clips the image display.
properties: Options for the display.

Remarks

This method will paint an overlay image. For more information on the paint rectangles, see Paint(RasterImage,Graphics,LeadRect,RasterPaintProperties).

Paint(RasterImage,Graphics,LeadRect,RasterPaintProperties) will paint all the overlays that have RasterOverlayAttributes.AutoPaint set to true. The overlays are painted in ascending index order: overlay 0 is painted first, then overlay 1, etc.

Use this method to manually paint an overlay. For example, to change the order in which the overlays are painted, set the RasterOverlayAttributes.AutoPaint property of the overlay to false then call PaintOverlay(RasterImage,Graphics,Int32,LeadRect,LeadRect,LeadRect,LeadRect,RasterPaintProperties) directly.

To temporarily make an overlay top-most, call PaintOverlay(RasterImage,Graphics,Int32,LeadRect,LeadRect,LeadRect,LeadRect,RasterPaintProperties) after Paint(RasterImage,Graphics,LeadRect,RasterPaintProperties). To permanently make an overlay top-most, change its index and give it the highest defined index.

The overlay image's 1 pixels are painted with the color set in the RasterOverlayAttributes.Color property of the overlay. The overlay image's 0 pixels are considered transparent.

For more information on the overlay attributes, including the RasterOverlayAttributes.AutoPaint property and the RasterOverlayAttributes.Color property, refer to Leadtools.RasterOverlayAttributes.

For more information, refer to Overlay Overview.

For more information refer to RasterImage and GDI/GDI+.

Example

C#
Visual Basic
WinRT C#
WinRT JavaScript
Silverlight C#
Silverlight VB

Copy Code

Imports Leadtools
Imports Leadtools.Codecs
Imports Leadtools.Drawing
Imports Leadtools.ImageProcessing

<TestMethod()> _
Public Sub PaintOverlayExample()
   Dim f As New PaintOverlayForm()
   f.ShowDialog()
End Sub
Class PaintOverlayForm
   Inherits Form
   Private image As RasterImage
   Private props As RasterPaintProperties

   Public Sub New()
      ' Load the image
      Dim codecs As New RasterCodecs()

      image = codecs.Load(LeadtoolsExamples.Common.ImagesPath.Path + "Image2.dcm")

      Using overlay As RasterImage = codecs.Load(LeadtoolsExamples.Common.ImagesPath.Path + "Ocr1.tif")
         Dim cmd As New ResizeCommand()
         Using destImage As New RasterImage(RasterMemoryFlags.Conventional, image.Width, image.Height, 1, RasterByteOrder.Bgr, image.ViewPerspective, Nothing, IntPtr.Zero, 0)
            cmd.Flags = RasterSizeFlags.FavorBlack
            cmd.DestinationImage = destImage
            cmd.Run(overlay)
            image.SetOverlayImage(0, destImage, RasterGetSetOverlayImageMode.Copy)
         End Using
      End Using

      Dim attributes As RasterOverlayAttributes = image.GetOverlayAttributes(0, _
         RasterGetSetOverlayAttributesFlags.Color Or _
         RasterGetSetOverlayAttributesFlags.Flags Or _
         RasterGetSetOverlayAttributesFlags.Origin Or _
         RasterGetSetOverlayAttributesFlags.BitIndex)

      attributes.AutoPaint = False
      attributes.Color = New RasterColor(255, 0, 0)

      image.UpdateOverlayAttributes( _
         0, _
         attributes, _
         RasterGetSetOverlayAttributesFlags.Color Or _
         RasterGetSetOverlayAttributesFlags.Flags Or _
         RasterGetSetOverlayAttributesFlags.Origin Or _
         RasterGetSetOverlayAttributesFlags.BitIndex)

      Text = "PaintOverlay Example"
      props = RasterPaintProperties.Default
      props.UsePaintPalette = True
   End Sub

   Protected Overrides Sub Dispose(ByVal disposing As Boolean)
      ' Clean up
      If disposing Then
         image.Dispose()
      End If

      MyBase.Dispose(disposing)
   End Sub

   Protected Overrides Sub OnPaint(ByVal e As PaintEventArgs)
      ' Draw the image fit and center on this form
      Dim destRect As LeadRect = LeadRect.FromLTRB(ClientRectangle.Left, ClientRectangle.Top, ClientRectangle.Right, ClientRectangle.Bottom)
      destRect = RasterImage.CalculatePaintModeRectangle( _
         image.ImageWidth, _
         image.ImageHeight, _
         destRect, _
         RasterPaintSizeMode.Fit, _
         RasterPaintAlignMode.Center, _
         RasterPaintAlignMode.Center)
      RasterImagePainter.Paint(image, e.Graphics, LeadRect.Empty, destRect, props)
      RasterImagePainter.PaintOverlay(image, e.Graphics, 0, LeadRect.Empty, LeadRect.Empty, destRect, LeadRect.Empty, props)

      MyBase.OnPaint(e)
   End Sub
End Class

using Leadtools;
using Leadtools.Codecs;
using Leadtools.Drawing;
using Leadtools.ImageProcessing;

[TestMethod]
public void PaintOverlayExample()
{
   PaintOverlayForm f = new PaintOverlayForm();
   f.ShowDialog();
}
class PaintOverlayForm : Form
{
   private RasterImage image;
   private RasterPaintProperties props;

   public PaintOverlayForm()
   {
      // Load the image
      RasterCodecs codecs = new RasterCodecs();

      image = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "Image2.dcm"));

      using(RasterImage overlay = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir,  "Ocr1.tif")))
      {
         ResizeCommand cmd = new ResizeCommand();
         using(RasterImage destImage = new RasterImage(RasterMemoryFlags.Conventional, image.Width, image.Height, 1, RasterByteOrder.Bgr, image.ViewPerspective, null, IntPtr.Zero, 0))
         {
            cmd.Flags = RasterSizeFlags.FavorBlack;
            cmd.DestinationImage = destImage;
            cmd.Run(overlay);
            image.SetOverlayImage(0, destImage, RasterGetSetOverlayImageMode.Copy);
         }
      }

      RasterOverlayAttributes attributes = image.GetOverlayAttributes(0,
         RasterGetSetOverlayAttributesFlags.Color |
         RasterGetSetOverlayAttributesFlags.Flags |
         RasterGetSetOverlayAttributesFlags.Origin |
         RasterGetSetOverlayAttributesFlags.BitIndex);

      attributes.AutoPaint = false;
      attributes.Color = new RasterColor(255, 0, 0);

      image.UpdateOverlayAttributes(
         0,
         attributes,
         RasterGetSetOverlayAttributesFlags.Color |
         RasterGetSetOverlayAttributesFlags.Flags |
         RasterGetSetOverlayAttributesFlags.Origin |
         RasterGetSetOverlayAttributesFlags.BitIndex);

      Text = "PaintOverlay Example";
      props = RasterPaintProperties.Default;
      props.UsePaintPalette = true;
   }

   protected override void Dispose(bool disposing)
   {
      // Clean up
      if(disposing)
      {
         image.Dispose();
      }

      base.Dispose(disposing);
   }

   protected override void OnPaint(PaintEventArgs e)
   {
      // Draw the image fit and center on this form
      LeadRect destRect = LeadRect.FromLTRB(ClientRectangle.Left, ClientRectangle.Top, ClientRectangle.Right, ClientRectangle.Bottom);
      destRect = RasterImage.CalculatePaintModeRectangle(
         image.ImageWidth,
         image.ImageHeight,
         destRect,
         RasterPaintSizeMode.Fit,
         RasterPaintAlignMode.Center,
         RasterPaintAlignMode.Center);
      RasterImagePainter.Paint(image, e.Graphics, LeadRect.Empty, destRect, props);
      RasterImagePainter.PaintOverlay(image, e.Graphics, 0, LeadRect.Empty, LeadRect.Empty, destRect, LeadRect.Empty, props);

      base.OnPaint(e);
   }
}

static class LEAD_VARS
{
public const string ImagesDir = @"C:\Users\Public\Documents\LEADTOOLS Images";
}

Requirements

Target Platforms

Reference

RasterImagePainter Class
RasterImagePainter Members
Overload List