[edit: most problems fixed, one problem remaining] Invalidate rectangle follow up, flickering and no movement

Calin Negru

[edit] I solved the background flickering problem by changing the last argument in the InvalidateRect() function to false. I also got the test rectangle moving. The only problem left is that the white moving rectangle is still flickering. [/edit] I wrote some code, for some reason the rectangle that should work as background is flickering and I can`t get a test rectangle to move. I`m pasting the source bellow, please help me get my code in proper configuration.

while (WM_QUIT != msg.message)
{
if (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
else
{
UpdateGame();
}
}

//...
switch (msg)
{
case WM_PAINT:
hdc = BeginPaint(hwnd, &ps);
draw(hdc);
movingR = movingR + 0.1;
RECT ARectangle;
ARectangle.left = 0;
ARectangle.top = 0;
ARectangle.right = 600;
ARectangle.bottom = 600;

InvalidateRect(hwnd, &ARectangle, false);
UpdateWindow(hwnd);

EndPaint(hwnd, &ps);
return 0;

//...

void draw(HDC hdc)
{
Gdiplus::Graphics gf(hdc);
Gdiplus::Pen pen(Gdiplus::Color(255, 255, 0, 0));
Gdiplus::SolidBrush brush(Gdiplus::Color(255, 0, 255, 0));
Gdiplus::SolidBrush brush2(Gdiplus::Color(255, 255, 255, 255));

gf.FillRectangle(&brush, 0, 0, 600, 600);
gf.FillRectangle(&brush2,(int)movingR, 200, 100, 100);

}
//...

void UpdateGame()
{
//movingR = movingR + 1;
}

Mircea Neacsu

You should use double buffering. Just google for “OpenGL double buffering”.

Mircea

Lost User

Do not call InvalidateRect and UpdateWindow from inside your WM_PAINT handler. You should be setting the rectangle's dimensions from outside the handler, and then calling InvalidateRect to cause the update to happen. Then when you get to the drawing code you get the rectangle details from inside the Paintstruct. Also using hardcoded values like you show above is not the correct way to do it.

Calin Negru

Richard and Mircea thanks for advice