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RasterPaintDibInfo Class
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This class describes the image data expected by the custom paint callbacks. It is used with the RasterPaintCallbacks callbacks.

Object Model

RasterPaintDibInfo Class

Syntax

Visual Basic (Declaration) 
Public Class RasterPaintDibInfo
Visual Basic (Usage)Copy Code
Dim instance As RasterPaintDibInfo
C# 
public class RasterPaintDibInfo
C++/CLI 
public ref class RasterPaintDibInfo

Example

This example will show how to indicate that the graphics device expects a 16-bit image with the image data in the low 12 bits. Also, this particular card expected the data to be top-down, unlike the usual GDI functions which expect the data to be upside-down.

The example is in C++/CLI because this is the most useful language for implementing these classes.

C#Copy Code
// macro that calculates the number of bytes per line, rounding up to a multiple of 4 bytes
#define DIB_WIDTH_BYTES(pixels) ((((pixels) + 31) & ~31) >> 3)
             
Object^ myPaintCallbacks::GetDibInfoCallback(RasterImage^ image, array<Object^>^ args)
{
   // make sure the parameters are correct
   if(args->Length != 2 || image == nullptr)
   {
      throw gcnew RasterException(RasterExceptionCode::InvalidParameter);
      return nullptr;
   }
   UInt32 uWidth = (UInt32)args[1];
   RasterPaintDibInfo^ pDibInfo = gcnew RasterPaintDibInfo;
   if(pDibInfo == nullptr)
   {
      throw gcnew RasterException(RasterExceptionCode::NoMemory);
      return nullptr;
   }
            
   pDibInfo->Default();
   pDibInfo->BitsPerPixel = 16;          // paint using 16-bit data, although there are only 12 significant bits
   pDibInfo->PlaneCount = 1;             // One plane
   pDibInfo->BytesPerLine = DIB_WIDTH_BYTES(uWidth * 16);   // bytes per line is a multiple of 4 bytes
   pDibInfo->ViewPerspective = RasterViewPerspective::TopLeft; // the data should be TOP_LEFT, not BOTTOM_LEFT like the data in the regular GDI functions
   pDibInfo->Order = RasterByteOrder::Gray;         // gray bitmap
            
   // indicate that the data should be in the low 12 bits
   pDibInfo->Flags = RasterPaintDibInfoFlags::LowHighBitValid;
   pDibInfo->LowBit = 0;
   pDibInfo->HighBit = 11;
            
   return pDibInfo;
}

Remarks

The user will typically allocate this class and return it from the RasterImagePaintCallbackFunction.GetDibInfoCallback callback.

Inheritance Hierarchy

System.Object
   Leadtools.Drawing.RasterPaintDibInfo

Requirements

Target Platforms: Silverlight 3.0, Windows XP, Windows Server 2003 family, Windows Server 2008 family, Windows Vista, Windows 7, MAC OS/X (Intel Only)

See Also