asked on

Getpixel

Hi,

I have loaded bitmap on the formview. I want the pixel color of bitmap where i left click the mouse button?

I wrote the following code in Lbuttondown() function but it is not working

COLORREF ref;
CDC *pDC = GetDC();
ref = GetPixel(point.x, point.y);

let me know what is the problem and Answer

bye
Arora

Arora

ASKER

Edited text of question.

arnond

better post this question in the windows programming area. you'd get much more traffic. After doing this, delete this question.

Arnon David.

BudVVeezer

your problem isn't so much where you post it(I know a LOT of programmers come to this section, including myself), it's with the GetDC call. Try this:

COLORREF c;
HDC dc = GetDC(hWnd);

c = GetPixel(x, y);

you can use point.x, point.y also if you choose, depends on how you handle the message. If this doesn work, send me the whole program, I'll figure it out! =)

~Aaron

BudVVeezer

OOPS! I forgot one thing, GetPixel(dc, x, y); LoL, tiny mistake. ;-P

~Aaron

ASKER CERTIFIED SOLUTION

GlennDean

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Arora

ASKER

Hi,

Ever I used HDC of the window as follows
HDC DC;
DC = GetDC(m_hWnd);
GetPixel( DC,point.x, point,Y);
still the GetPixel function is not succeeding.

bye
Arora

GlennDean

Arora:
Can you get the above code to even compile? IF you're in your LBUTTONDOWN handler, then the compiler "thinks" the
line
DC = GetDC(m_hWnd);
is trying to call the CDC class's GetDC function and won't compile. BUT, if you write
DC = ::GetDC(m_hWnd);
then it compiles fine because the compiler now knows you want the WIN32 API function GetDC.
The code I listed in my proposed answer works (on my computer), BUT if you want to use the WIN32 API functions then write:
HDC DC;
DC = ::GetDC(m_hWnd);
COLORREF color = ::GetPixel(point.x,point.y);
This works on my computer.
Glenn

GlennDean

OOPS! Change the above line to
COLORREF color = ::GetPixel(DC,point.x,point.y);