GetPixel and LoadLibrary gdi32.dll

[engmaster]

Hello,

I'm not accustomed to Visual C ++ and need a BIG help.

I hnow that I can use direct GetPixel including the windows.h, buy I need other way to call this func.
So.. I try it:
It'is a simple W32 Console app.

#include "stdafx.h"
#include "windows.h"
#include <windows.h>
#include <stdio.h>

int main()
{
	FARPROC pGetPixel;
	HINSTANCE _hGDI = LoadLibrary(L"gdi32.dll");
	if (_hGDI)
	{
		pGetPixel = GetProcAddress(_hGDI, "GetPixel");
		HDC _hdc = GetDC(NULL);
		if (_hdc)
		{
			while (1)
			{
				POINT _cursor;
				GetCursorPos(&_cursor);
				COLORREF _color = (*pGetPixel) (_hdc, _cursor.x, _cursor.y);
				int _red = GetRValue(_color);
				int _green = GetGValue(_color);
				int _blue = GetBValue(_color);

				printf("Red: %d\n", _red);
				printf("Green: %d\n", _green);
				printf("Blue: %d\n", _blue);
				Sleep(2000);
			}
		}
		FreeLibrary(_hGDI);
	}
	return 0;
}

But I have error on line:

COLORREF _color = (*pGetPixel) (_hdc, _cursor.x, _cursor.y);

Why I dont able to use it? How to I do it?

The Output from VS2015 C++

1>------ Rebuild All started: Project: GetPix, Configuration: Debug Win32 ------
1>  stdafx.cpp
1>  GetPix.cpp
1>c:\users\ ... \getpix.cpp(23): error C2197: 'int (__stdcall *)(void)': too many arguments for call
========== Rebuild All: 0 succeeded, 1 failed, 0 skipped ==========

[VictorN]

Hello,

I'm not accustomed to Visual C ++ and need a BIG help.

I hnow that I can use direct GetPixel including the windows.h, buy I need other way to call this func.
So.. I try it:
It'is a simple W32 Console app.

#include "stdafx.h"
#include "windows.h"
#include <windows.h>
#include <stdio.h>

int main()
{
	FARPROC pGetPixel;
	HINSTANCE _hGDI = LoadLibrary(L"gdi32.dll");
	...
	return 0;
}

But I have error on line:

COLORREF _color = (*pGetPixel) (_hdc, _cursor.x, _cursor.y);

Why I dont able to use it? How to I do it?

The Output from VS2015 C++

1>------ Rebuild All started: Project: GetPix, Configuration: Debug Win32 ------
1>  stdafx.cpp
1>  GetPix.cpp
1>c:\users\ ... \getpix.cpp(23): error C2197: 'int (__stdcall *)(void)': too many arguments for call
========== Rebuild All: 0 succeeded, 1 failed, 0 skipped ==========

You declared the pGetPixel as void and without the arguments.
Why?
Also see the example in GetProcAddress function article

[VictorN]

[moved thread...]

[engmaster]

VictorN,
I am very grateful for your information. (GetProcAddress function)
Thank you!!!

Now the code work!
But, I do it corret? Or still have any mistake.

#include "stdafx.h"
#include <windows.h>
#include <stdio.h>

typedef int(__stdcall *MYPROC)(HDC hd, int x, int y);

/* 
(Original) GetPixel(
_In_ HDC hdc,
_In_ int nXPos,
_In_ int nYPos )
*/
HINSTANCE hinstLib;
MYPROC ProcAdd;

int main()
{
	//FARPROC pGetPixel;

	hinstLib = LoadLibrary(TEXT("gdi32.dll"));
	if (hinstLib)
	{
		ProcAdd = (MYPROC)GetProcAddress(hinstLib, "GetPixel");
		HDC _hdc = GetDC(NULL);
		if (_hdc)
		{
			while (1)
			{
				POINT _cursor;
				GetCursorPos(&_cursor);
				COLORREF _color = (*ProcAdd) (_hdc, (int)_cursor.x, (int)_cursor.y);
				int _red = GetRValue(_color);
				int _green = GetGValue(_color);
				int _blue = GetBValue(_color);

				printf("Red: %d\n", _red);
				printf("Green: %d\n", _green);
				printf("Blue: %d\n", _blue);
				Sleep(100);
			}
		}
		FreeLibrary(hinstLib);
	}
    return 0;
}

Thank you!

[engmaster]

But, I do it right? Or still have some mistake. ****