LVectorBase::Paint

#include "ltwrappr.h"

virtual L_INT LVectorBase::Paint(hdc, bEraseBkgnd)

Draws the specified vector into a given device context.

Parameters

HDC hdc

Device context.

L_BOOL bEraseBkgnd

Flag that indicates whether or not to erase the background rectangle when rendering the vector. Possible values are:

Returns

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.

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; 
}