public int BitsPerPixel { get; set; }
Valid values are 0, 1, 2, 3, 4, 5, 6, 7, 8, 12, 16, 24, 32, 48, and 64.
The image data will need to be converted to these bits per pixel before the RasterImagePaintCallbackFunction.StretchDIBitsCallback callback. The conversion will be performed by the built-in conversion function or the RasterImagePaintCallbackFunction.ConvertLineCallback callback
using Leadtools;
using Leadtools.Codecs;
using Leadtools.Drawing;
public void RasterPaintPropertiesExample()
{
// Create the form
RasterPaintDibInfo_Example f = new RasterPaintDibInfo_Example();
f.ShowDialog();
}
public void AddCallBack()
{
// Load the image
RasterCodecs codecs = new RasterCodecs();
string srcFileName = Path.Combine(LEAD_VARS.ImagesDir, "Ocr1.tif");
image = codecs.Load(srcFileName);
// Whenever the Leadtools.RasterImage object needs to paint,
// it searches through the RasterPaintProperties.PaintCallbacks list until it finds
// a compatible RasterPaintCallbacks object. If the list is empty or there is no compatible
// RasterPaintCallbacks object, the default paint functions are used.
RasterPaintCallbacks cb = new RasterPaintCallbacks();
cb.SetCallback(RasterImagePaintCallbackFunction.GetDibInfoCallback, DibFunctionDelegate);
props = RasterPaintProperties.Default;
props.PaintDisplayMode = RasterPaintDisplayModeFlags.FastPaint;
props.PaintCallbacks.Add(cb);
props.PaintEngine = RasterPaintEngine.GdiPlus;
}
private object DibFunctionDelegate(RasterImage image, object[] args)
{
// Describe the image data expected by the custom paint callback:
// RasterImagePaintCallbackFunction.GetDibInfoCallback.
//
// Set and use as needed in application, in this case the values are taken from image.
// Then return the updated RasterPaintDibInfo
rasterPaintDibInfo.BitsPerPixel = image.BitsPerPixel;
rasterPaintDibInfo.BytesPerLine = Convert.ToUInt32(image.BytesPerLine);
rasterPaintDibInfo.Flags = RasterPaintDibInfoFlags.LowHighBitValid | RasterPaintDibInfoFlags.IgnoreLut;
rasterPaintDibInfo.Order = RasterByteOrder.Bgr;
rasterPaintDibInfo.ViewPerspective = RasterViewPerspective.RightTop;
return rasterPaintDibInfo;
}
public void RasterImagePainterPaint(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);
}
protected override void OnPaint(PaintEventArgs e)
{
RasterImagePainterPaint(e);
base.OnPaint(e);
}
protected override void OnDoubleClick(EventArgs e)
{
if ((props.PaintDisplayMode & RasterPaintDisplayModeFlags.ScaleToGray) == RasterPaintDisplayModeFlags.ScaleToGray)
{
Text = "Normal - doubleclick to change.";
props.PaintDisplayMode &= ~RasterPaintDisplayModeFlags.ScaleToGray;
}
else
{
Text = "ScaleToGray - doubleclick to change.";
props.PaintDisplayMode |= RasterPaintDisplayModeFlags.ScaleToGray;
}
Invalidate();
base.OnDoubleClick(e);
}
static class LEAD_VARS
{
public const string ImagesDir = @"C:\LEADTOOLS23\Resources\Images";
}