Animation blitting with C++11 help please.

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GUI

C++11

I have read about using buffers to move a ball on the screen.

I am using C++11 on Microsoft Windows 32 bit.

No visual C++. No Visual Basic. No .NET. No Active X. Please.

Thank you.

Would you please look at what I have and adjust it to correct logic? It works but I want it to be better.

Thank you.

//  Each time that this proceedure is called four (4) buffers are created.
//  The hdcBacdkgroundBitmapBuffer will be stretch blitted to the
//  hdcWorkingBackBuffer. This will be behind the animation and is placed
//  there EVERY time that the animation changes in order to erase the
//  previous animation.
//
//  The hdcAnimationBuffer_001 will have the animation mask placed into
//  it with SRCAND.
//  The hdcAnimationBuffer_001 will have the animation bitmap placed into
//  it with SRCPAINT.
//  With the mask and bitmap combined the hdcAnimationBuffer_001 will have
//  a custom shaped region.
//            
//  I am not certain what the hbmOldBuffer does. I think that it is not
//  necessary but I do not know.
//
//  The hdcWorkingBackBuffer will be blitted to the screen which in this
//  case is hdc.
//
void DrawBall(HDC hdc, RECT* prc)
{
   //  This creates a back buffer to blt to.
   HDC hdcWorkingBackBuffer = CreateCompatibleDC(hdc);

   //  HBITMAP is An object handle that manages bitmap data.
   HBITMAP hbmBuffer = CreateCompatibleBitmap(hdc, prc->right, prc->bottom);

   //  Where is this hbmOldBuffer used? It looks like it is created, then
   //  a lot of stuff is done without it, then it is selected (not used) and
   //  then deleted. What is the use of the next line?
   HBITMAP hbmOldBuffer = (HBITMAP)SelectObject(hdcWorkingBackBuffer, hbmBuffer);

   // This puts the background in place. EACH TIME! BEFORE the animation is put
   // into place.
   // This creates another buffer for the background bitmap to be blitted from.
   HDC hdcBacdkgroundBitmapBuffer = CreateCompatibleDC(hdc);
   HBITMAP hbmOldRed =
      (HBITMAP)SelectObject(hdcBacdkgroundBitmapBuffer, g_RedGreenBlue);

   //  This blitts the background buffer onto a back buffer.
   StretchBlt(hdcWorkingBackBuffer, 0, 0, 320, 240,
      hdcBacdkgroundBitmapBuffer, 0, 0, 320, 240, SRCCOPY);

   //  This puts the animation in place. EACH TIME! AFTER the animation is put
   //  into place.
   //  This creates another buffer for the animation bitmap to be blitted from.
   HDC hdcAnimationBuffer_001 = CreateCompatibleDC(hdc);

   //  What is hbmOld and why is it not defined earlier like
   //     HBITMAP g_hbmMask = NULL; is?
   //  Why can't I say (HBITMAP hbmOld = NULL) and then say
   //     hbmOld = (HBITMAP)SelectObject(hdcAnimationBuffer_001, g_hbmMask); ?
   //  Doesn't that mean that hbmOld has to be defined over and over again as
   //  DrawBall is called or used?
   //  That seems kind of inefficient to me unless there is some reason for
   //  doing it this was being better.
   //  What is the next line doing and why is it necessary (in full) here?
   HBITMAP hbmOld = (HBITMAP)SelectObject(hdcAnimationBuffer_001, g_hbmMask);

   //  Does the next line put the ball image into a back buffer? I think that
   //  it does. Is this hdcWorkingBackBuffer what a pointer would point to if
   //  I had an animation? Please explain your answer.
   BitBlt(hdcWorkingBackBuffer, g_ballInfo.x, g_ballInfo.y, g_ballInfo.width, 
      g_ballInfo.height, hdcAnimationBuffer_001, 0, 0, SRCAND);

   //  What is the use of the next line?
   //  Would it be more efficient to use a pointer to the bitmap?
   SelectObject(hdcAnimationBuffer_001, g_hbmBall);
   BitBlt(hdcWorkingBackBuffer, g_ballInfo.x, g_ballInfo.y, g_ballInfo.width,
      g_ballInfo.height, hdcAnimationBuffer_001, 0, 0, SRCPAINT);
   //  Like this
   //  BitBlt(hdcWorkingBackBuffer, g_ballInfo.x, g_ballInfo.y, g_ballInfo.width,
   //     g_ballInfo.height, [pointer to the bitmap in memory], 0, 0, SRCPAINT);

   //  This blitts the working (composted) buffer to the front (screen) buffer.
   BitBlt(hdc, 0, 0, prc->right, prc->bottom, hdcWorkingBackBuffer,
       0, 0, SRCCOPY);

   //  Background stuff
   SelectObject(hdcAnimationBuffer_001, hbmOldRed);
   DeleteDC(hdcBacdkgroundBitmapBuffer);

   //  Animation stuff
   SelectObject(hdcAnimationBuffer_001, hbmOld);
   DeleteDC(hdcAnimationBuffer_001);

   //  Why are we selecting and then deleting the following when we never
   //  used it (as far as I know)?
   SelectObject(hdcWorkingBackBuffer, hbmOldBuffer);
   DeleteDC(hdcWorkingBackBuffer);
   DeleteObject(hbmBuffer);

   //  Where is the part that fills a back buffer or two (etc.) of them and
   //  then "points" to them? It looks like a buffer is filled, then copied
   //  instead of pointed to, then deleted. That looks not so efficient, or
   //  maybe I am wrong about this. I would like to have 5 buffers that I can
   //  fill once or re-fill as I like and then "point" to them or whatever
   //  that is. Help!
}

What I have tried:

I have studied this and I think that I am beginning to understand the creation of an animation via blitting, and more specifically how to do this with a bitmap background. But now that it works, I have been trying to further understand what it is doing.

I have added comments. I would like someone that is more advanced than me to look at it and correct where I am wrong.

It works but I want it to be better.

Thank you.