LVectorBase::Paint

#include "ltwrappr.h"

virtual L_INT LVectorBase::Paint(hdc, bEraseBkgnd)

HDC hdc;	/* device context */
L_BOOL bEraseBkgnd;	/* flag that indicates whether to erase the background */

Draws the specified vector into a given device context.

Parameter	Description
hdc	Device context.
bEraseBkgnd	Flag that indicates whether or not to erase the background rectangle when rendering the vector. Possible values are:
	Value	Meaning
	TRUE	The background rectangle will be erased when the vector image is rendered to the device context.
	FALSE	The background rectangle will not be erased.

Returns

SUCCESS	The function was successful.
< 1	An error occurred. Refer to Return Codes.

Comments

If hDC is NULL, this function will assume that the vector is already attached to a window, and will draw the vector image to the window DC.

The background color used to erase the rectangle where the vector image is rendered can be set with LVectorBase::SetBackgroundColor.

If LVectorBase::Paint is called in response to a WM_PAINT message, hDC should be the paint DC obtained from BeginPaint.

This function will use current camera and current viewport of the vector handle to do the necessary projection into the surface of the DC.

Required DLLs and Libraries

LVKRN

For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application.

See Also

Functions:	LVectorBase::Realize, LVectorBase::AttachToWindow, LVectorBase::SetCamera, LVectorBase::SetViewport, LVectorBase::SetBackgroundColor
Topics:	Vector Images: Viewing a Vector Image

Example

L_INT LVectorBase__PaintExample(HWND hWnd, LVectorBase &Vector)
{
   L_INT       nRet;
   HDC         hdc;
   PAINTSTRUCT ps;
   RECT        rect;
   HPALETTE    hOldPalette = NULL, hPal;
   hdc = BeginPaint (hWnd, &ps) ;
   GetClientRect(hWnd, &rect);
   nRet = Vector.SetViewport(&rect);
   if(nRet != SUCCESS)
      return nRet;
   if (Vector.IsAllocated())
   {
      // Create the palette that we will use to paint 
      hPal = Vector.GetPalette();
      if( hPal )
      {
         hOldPalette = ::SelectPalette( hdc, hPal, TRUE );
         ::RealizePalette( hdc );
      }
      nRet = Vector.Paint(hdc, TRUE);
      if(nRet != SUCCESS)
         return nRet;
      if (hOldPalette)
      {
         ::SelectPalette (hdc, hOldPalette, FALSE);
         DeleteObject(hPal);
      }
   }
   EndPaint (hWnd, &ps) ;
   return SUCCESS;
}