C language > Windows questions

Color inside the "Ellipse"

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alderman2:
I need to use the "Ellipse" function in a program I'm working on.  I can color the edges around but not inside the circle.  I've tried everything I can find on how to but nothing has worked yet.  The others I've seen do this use add-on libraries, but I don't want to do that.
 Anyone know the easiest way to color the circle surface with any color?

This is what it looks like when I can color the border around the circle, but how do you paint in the circle:

HPEN hpen,hpenOld;

   PAINTSTRUCT    ps ;
   BeginPaint(hwnd, &ps);



    hpen=CreatePen(PS_SOLID,0,color);
    hpenOld=SelectObject(hDC,hpen);
 
      Ellipse( hDC, 400, 300,200, 200);

    SelectObject(hDC,hpenOld);
    DeleteObject(hpen);

TimoVJL:
Using Filled Shapes

alderman2:

--- Quote from: TimoVJL on December 17, 2022, 10:43:23 PM ---Using Filled Shapes

--- End quote ---

I solved it!!!  After two weeks of trying, and when I finally post the question here, I found the solution!

This is how it works:

--- Code: ---HDC hDC;
HBRUSH hBrush;

hDC = GetDC(hwnd);

hBrush = CreateSolidBrush (RGB(0, 0, 255));

SelectObject (hDC, hBrush);


Ellipse( hDC, 300, 300, 100, 100);
--- End code ---


Is there something missing in the code?

MrBcx:

--- Quote from: alderman2 on December 17, 2022, 11:14:18 PM ---Is there something missing in the code?

--- End quote ---

Impossible to say because you only shared a fragment of code.
The function below was copied from the BCX runtime library.
It might provide clues that you can use.


--- Code: ---  int BCX_Circle (HWND Wnd, int X, int Y, int R, int Pen, int Fill, HDC DrawHDC)
        {
          int a,b=0;
          if (!DrawHDC) DrawHDC=GetDC(Wnd),b=1;
          HPEN   hNPen=CreatePen(PS_SOLID,1,Pen);
          HPEN   hOPen=(HPEN)SelectObject(DrawHDC,hNPen);
          HBRUSH hOldBrush;
          HBRUSH hNewBrush;
          if (Fill)
          {
            hNewBrush=CreateSolidBrush(Pen);
            hOldBrush=(HBRUSH)SelectObject(DrawHDC,hNewBrush);
          }
          else
          {
            hNewBrush=(HBRUSH)GetStockObject(NULL_BRUSH);
            hOldBrush=(HBRUSH)SelectObject(DrawHDC,hNewBrush);
          }
          a = Ellipse(DrawHDC,X-R,Y+R,X+R,Y-R);
          DeleteObject(SelectObject(DrawHDC,hOPen));
          DeleteObject(SelectObject(DrawHDC,hOldBrush));
          if (b) ReleaseDC(Wnd,DrawHDC);
          return a;

--- End code ---

John Z:
Hi MrBcx,


--- Quote from: MrBcx on December 18, 2022, 12:42:59 AM ---
--- Code: --- if (!DrawHDC) DrawHDC=GetDC(Wnd),b=1;

--- End code ---

--- End quote ---

This code snippet works? I've never seen this syntax, I surmise if no HDC it will get one, then it will set b equal to 1
as a flag to later allow the release of the DC;  but I've never run across this use of a comma..... I would have had to write

--- Code: --- if (!DrawHDC)
  { DrawHDC=GetDC(Wnd) ; b=1;}

--- End code ---

Are multiple commas allowed too? As in
 if (!DrawHDC) DrawHDC=GetDC(Wnd),b=1,c=2,d=3;

John Z

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