Screen Capture Program
 

I am creating this simple program that will capture screen shots. I want to make it so the name of the image that is saved is what the user enters into a text field before the picture is taken. and if at all possible is there a way to make this window pop up above the game screen when a key combination is pressed?

thanks! this is the code i have so far btw.

#include<iostream>

#include<windows.h>

using namespace std;



inline int GetFilePointer(HANDLE FileHandle){

        return SetFilePointer(FileHandle, 0, 0, FILE_CURRENT);

}



bool SaveBMPFile(char *filename, HBITMAP bitmap, HDC bitmapDC, int width, int height){

        bool Success=0;

        HDC SurfDC=NULL;

        HBITMAP OffscrBmp=NULL;

        HDC OffscrDC=NULL;

        LPBITMAPINFO lpbi=NULL;

        LPVOID lpvBits=NULL;

        HANDLE BmpFile=INVALID_HANDLE_VALUE;

        BITMAPFILEHEADER bmfh;

        if ((OffscrBmp = CreateCompatibleBitmap(bitmapDC, width, height)) == NULL)

                return 0;

        if ((OffscrDC = CreateCompatibleDC(bitmapDC)) == NULL)

                return 0;

        HBITMAP OldBmp = (HBITMAP)SelectObject(OffscrDC, OffscrBmp);

        BitBlt(OffscrDC, 0, 0, width, height, bitmapDC, 0, 0, SRCCOPY);

        if ((lpbi = (LPBITMAPINFO)(new char[sizeof(BITMAPINFOHEADER) + 256 * sizeof(RGBQUAD)])) == NULL)

                return 0;

        ZeroMemory(&lpbi->bmiHeader, sizeof(BITMAPINFOHEADER));

        lpbi->bmiHeader.biSize = sizeof(BITMAPINFOHEADER);

        SelectObject(OffscrDC, OldBmp);

        if (!GetDIBits(OffscrDC, OffscrBmp, 0, height, NULL, lpbi, DIB_RGB_COLORS))

                return 0;

        if ((lpvBits = new char[lpbi->bmiHeader.biSizeImage]) == NULL)

                return 0;

        if (!GetDIBits(OffscrDC, OffscrBmp, 0, height, lpvBits, lpbi, DIB_RGB_COLORS))

                return 0;

        if ((BmpFile = CreateFile(filename,

                                                GENERIC_WRITE,

                                                0, NULL,

                                                CREATE_ALWAYS,

                                                FILE_ATTRIBUTE_NORMAL,

                                                NULL)) == INVALID_HANDLE_VALUE)

                return 0;

        DWORD Written;

        bmfh.bfType = 19778;

        bmfh.bfReserved1 = bmfh.bfReserved2 = 0;

        if (!WriteFile(BmpFile, &bmfh, sizeof(bmfh), &Written, NULL))

                return 0;

        if (Written < sizeof(bmfh))

                return 0;

        if (!WriteFile(BmpFile, &lpbi->bmiHeader, sizeof(BITMAPINFOHEADER), &Written, NULL))

                return 0;

        if (Written < sizeof(BITMAPINFOHEADER))

                return 0;

        int PalEntries;

        if (lpbi->bmiHeader.biCompression == BI_BITFIELDS)

                PalEntries = 3;

        else PalEntries = (lpbi->bmiHeader.biBitCount <= 8) ?

                                          (int)(1 << lpbi->bmiHeader.biBitCount) : 0;

        if(lpbi->bmiHeader.biClrUsed)

        PalEntries = lpbi->bmiHeader.biClrUsed;

        if(PalEntries){

        if (!WriteFile(BmpFile, &lpbi->bmiColors, PalEntries * sizeof(RGBQUAD), &Written, NULL))

                return 0;

                if (Written < PalEntries * sizeof(RGBQUAD))

                        return 0;

        }

        bmfh.bfOffBits = GetFilePointer(BmpFile);

        if (!WriteFile(BmpFile, lpvBits, lpbi->bmiHeader.biSizeImage, &Written, NULL))

                return 0;

        if (Written < lpbi->bmiHeader.biSizeImage)

                return 0;

        bmfh.bfSize = GetFilePointer(BmpFile);

        SetFilePointer(BmpFile, 0, 0, FILE_BEGIN);

        if (!WriteFile(BmpFile, &bmfh, sizeof(bmfh), &Written, NULL))

                return 0;

        if (Written < sizeof(bmfh))

                return 0;

        return 1;

}

bool ScreenCapture(int x, int y, int width, int height, char *filename){

        HDC hDc = CreateCompatibleDC(0);

        HBITMAP hBmp = CreateCompatibleBitmap(GetDC(0), width, height);

        SelectObject(hDc, hBmp);

        BitBlt(hDc, 0, 0, width, height, GetDC(0), x, y, SRCCOPY);

        bool ret = SaveBMPFile(filename, hBmp, hDc, width, height);

        DeleteObject(hBmp);

        return ret;

}



int main() {

        int x1 = 0;

        int y1 = 0;

        int x2 = GetSystemMetrics(SM_CXSCREEN);

        int y2 = GetSystemMetrics(SM_CYSCREEN);

        ScreenCapture(x1, y1, x2 - x1, y2 - y1, "rename_me_before_upload.bmp");

        cin.ignore();

        return 0;

}

Re: Screen Capture Program
 

If all you want to do is let allow the user to input the bitmap name, use std::cin to get the name, and strcat ".bmp" on the end. Change your main code like this:

int main() {

  int x1 = 0;

  int y1 = 0;

  int x2 = GetSystemMetrics(SM_CXSCREEN);

  int y2 = GetSystemMetrics(SM_CYSCREEN);



  char bmp_name[100];

  cin.getline( bmp_name, 96 );

  strcat( bmp_name, ".bmp" );





  ScreenCapture(x1, y1, x2 - x1, y2 - y1, bmp_name);



  cin.ignore();

  return 0;

}

>if at all possible is there a way to make this window pop up above the game screen when a key combination is pressed?
Not quite sure what you mean by this.

Re: Screen Capture Program
 

Since this program is a anti-cheat parameter for the league, the picture wont be needed till once the player is in game. so once in game i would like the players to push lets say Shift+Alt+S to bring up the console app over top the game. Then once the picture is taken and saved then push Shift+Alt+S to minimize the console behind the top screen again.

Re: Screen Capture Program
 

Okay, that's tricky but possible. In this small example, I check to see if those keys are down. If they are down, it will toggle the windows visibility. I tried using windows hooks to give this example, but I couldn't set the hook without having a hInstance, so I tried this alternative method which works on console windows.

#define _WIN32_WINNT 0x0500

#include <windows.h>

#include <iostream>

using namespace std;



int main() {

  bool visible = false;

  ShowWindow( GetConsoleWindow(), SW_HIDE );



  for ( ; ; ) {



    if ( GetAsyncKeyState( VK_SHIFT ) &&

         GetAsyncKeyState( VK_MENU ) &&

         GetAsyncKeyState( VkKeyScanA('s') ) )

    {

      if ( visible )

        ShowWindow( GetConsoleWindow(), SW_HIDE );

      else

        ShowWindow( GetConsoleWindow(), SW_SHOW );



      visible = !visible;

      Sleep( 500 );

    }



    Sleep( 100 );

  }



  cin.ignore();

}

Whether or not ShowWindow will be enough to bring the console window in front of the game, I don't know, but that would be the next stage if the above doesn't work.

Hope this helps.

Code tags don't seem to work correctly, and can't get the C++ syntax, not sure why.

Re: Screen Capture Program
 

Alright. So i havent compiled any programs for a while and im compiling this using the Microsoft Visual C++ Toolkit 2003. When i click build it gives me an error saying:
Any idea what is wrong? And im building this in CodeBlocks 8.02.

Hello,

I'm trying to use the code in the first post to capture a smaller area than the whole screen. I have a point that is at the center of the area I need to capture. In my main() function I call ScreenCapture(xPos - 25, yPos - 25, 50, 50, "image.bmp"), where xPos is the x-position of the center and yPos is the y-position of the center point.

Everything is running OK, but the saved image is black. It has the right size, but it's black. What am I doing wrong?

Thanx!

What OS are you using ?

Windows Vista 32bit. Capturing the whole screen works well. I get normal screen shot.