wm_paint : 100% cpu

[kiberg]

Hi

When I listen WM_PAINT event, the cpu is max.

LRESULT CALLBACK WindowProcedure(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
int x, y;  HDC hdc; HPEN hOldPen, hPen; HBRUSH hOldBrush, hBrush;
y = lParam / 65536;
x = lParam % 65536;
    switch (message)
    {  // SetTextColor(hdc,RGB(0,0,255));
             //SetBkColor(hdc, RGB(236,232,245));
           case WM_DESTROY:
           PostQuitMessage(0);
           break;
           case WM_PAINT:
              hdc=GetDC(hwnd);
              hPen= CreatePen(PS_SOLID, 1, RGB(215, 0, 0));
              hOldPen=(HPEN)SelectObject(hdc,hPen);
 
              //drawing
 
              SelectObject(hdc,hOldPen);
              DeleteObject(hPen);
              SelectObject(hdc,hOldBrush);
              DeleteObject(hBrush);
              ReleaseDC(hwnd,hdc);
 
           break;
           case WM_MOUSEMOVE:
            //.....
           break;
           case WM_LBUTTONDOWN:
              //.... 
           break;
           default:
           return DefWindowProc(hwnd, message, wParam, lParam);
    }
  }
 

So, I think the wm_paint message every time run.(if need not redraw the window at the time, run wm_paint message, too)
What can I do?
thanks!

[Banfa]

You should not be calling GetDC(...) and ReleaseDC(...) from the WM_PAINT message.

The are special functions for this, instead you should use BeginPaint(...) and EndPaint(...).

See the example here.

I am afraid it is not clear to me what you mean by "when I listen WM_PAINT event".

[kiberg]

I am afraid it is not clear to me what you mean by "when I listen WM_PAINT event".
Sorry, i dont speak english only little...
But your solution is good.
Thank you very much!