아래글에서 물음표 표시한곳에서
GetRValue(StartColor) 함수에 대한 내용이 없는데 어떻게
이용해야 되나요?
소스를 보면

Tcolor StartColor = clBlue;

int InitialRed   = GetRValue(StartColor);   
이렇게 되어 있는걸로 봐선.. color값을 받아서 int값으로 변경하는것 같은데..
제가 잘 몰라서....

아래 소스를 좀 변경해서 사용하려구 하는데...
GetRValue(StartColor)함수에 대한 내용이 없어서....
도움 바랍니다...



방태윤 님이 쓰신 글 :
: void __fastcall DrawClientWindow (HDC &Hdc)
: {
:   // this routine paints a gradient background that slowly
:   // changes from StartColor at the top to black at the bottom
:   const int    NumGradients = 64;   // number of shading levels
:   const TColor StartColor = clBlue; // initial color
:
:   TRect rect ;                      // calculate size of backgnd
:   ::GetClientRect (Form1->Handle, (RECT *) &rect) ;
:
:   // painting a shaded gradient is slow, and can cause flickering
:   // eliminate flicker by using memory bitmaps and BitBlit
:   Graphics::TBitmap *MemBitmap = new Graphics::TBitmap;
:   MemBitmap->Width = rect.Right - rect.Left;
:   MemBitmap->Height= rect.Bottom- rect.Top;
:   MemBitmap->Canvas->Brush->Style = bsSolid;
:   MemBitmap->Canvas->Brush->Color = clBlack;
:   MemBitmap->Canvas->FillRect(Rect(0,0,
:                                    MemBitmap->Width,
:                                    MemBitmap->Height));
:   // calculate the height of each little gradient section
:   int GradientHeight = MemBitmap->Height / NumGradients;
:
:   // calculate individual RGB intensities of the starting color.
:   int InitialRed   = GetRValue(StartColor);    ---------------------????
:   int InitialGreen = GetGValue(StartColor);    ---------------------????
:   int InitialBlue  = GetBValue(StartColor);    ---------------------????
:   int RedIncrement  = (InitialRed + 1)  / NumGradients; // calculate
:   int GreenIncrement= (InitialGreen + 1)/ NumGradients; // increment of
:   int BlueIncrement = (InitialBlue + 1) / NumGradients; // each gradient
:
:   TColor FillColor;
:   // the for loop draws each gradient section. the loop stops one pass
:   // away from black because black was drawn by FillRect above
:   for (int j=0;j< NumGradients;j++)
:   {
:     rect.Bottom = rect.Top + GradientHeight;
:     FillColor = (TColor) RGB( InitialRed   -(RedIncrement * j),
:                               InitialGreen -(GreenIncrement* j),
:                               InitialBlue  -(BlueIncrement * j));
:     MemBitmap->Canvas->Brush->Color = FillColor;
:     MemBitmap->Canvas->FillRect(rect);
:     rect.Top += GradientHeight;
:   }
:   // Use API BitBlt to copy pixels to the screen.
:   ::BitBlt(Hdc,0,0,MemBitmap->Width, MemBitmap->Height,
:            MemBitmap->Canvas->Handle,0,0,SRCCOPY);
:   delete MemBitmap; // delete the temporary bitmap.
: }
: void __fastcall TForm1::Button1Click(TObject *Sender)
: {
:   DrawClientWindow(Canvas->Handle);
: }
: <출처를알수없음>
:
: 박용우 님이 쓰신 글 :
: : 그라데이션 효과 아시죠..
: : 점점 진해진다든지 점점 밝아지는 그런 효과를 주려고하는데
: : 어떻게 하시는지 아시는분
: : 캔버스에 사각형을 그리고 싶어요 입체감있게 보이는.