Dear Friends
I am wirting an application for drawing a rectangle on the screen using opengl and mfc. So I implemented the OnPaint function, OnDraw function is also giving the same problem. It's drawing fine. I want to implement pan, zoom, and rotate functionalities. Now everytime the mouse moves I am calling Invalidate() or otherwise I can call Invalidate()
in the ::OnDraw function
. Pan, zoom and rotate everything is happening but its heavily flickering. I have serached a lot and tried all means like return 1 in the OnEraseBackground()
functio for WM_ERASEBACKGROUND
etc. But I am getting still flickering . Please help getting rid of this problem. Check the code snippet below.
void CRevolutionProjView::OnPaint()
{
CPaintDC dc(this); // device context for painting
// TODO: Add your message handler code here
CRect RectAff;
GetClientRect(RectAff);
glClearColor ( 0.0f, 0.0f, 0.0f, 0.0f ) ;
glClear ( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT ) ;
glPushMatrix( ) ;
glTranslatef(trans[0], trans[1], trans[2]);
glRotatef(rot[0], 1.0f, 0.0f, 0.0f);
glRotatef(rot[1], 0.0f, 1.0f, 0.0f);
drawcube();
glPopMatrix( ) ;
glFinish( ) ;
glFlush();
SwapBuffers(hDC);
Invalidate(false);
// Do not call CView::OnPaint() for painting messages
}
void CRevolutionProjView::OnMouseMove(UINT nFlags, CPoint point)
{
newP = point;
// TODO: Add your message handler code here and/or call default
int dx = oldP.x - newP.x;
int dy = newP.y - oldP.y;
switch(STATE)
{
case PAN:
{
trans[0] -= dx/100.0f;
trans[1] -= dy/100.0f;
// Invalidate();
}
break;
case ZOOM:
{
trans[2] -= (dx+dy) / 100.0f;
// Invalidate();
}
break;
case ROTATE:
{
rot[0] += (dy * 180.0f) / 500.0f;
rot[1] -= (dx * 180.0f) / 500.0f;
#define clamp(x) x = x > 360.0f ? x-360.0f : x < -360.0f ? x+=360.0f : x
clamp(rot[0]);
clamp(rot[1]);
// Invalidate();
}
break;
}
oldP = newP;
CView::OnMouseMove(nFlags, point);
}