Hello you guys. I'm working a bit on improving my C++ so I decided to mess around with screenshots. it's windows based an uses gdiplus and windows api. It gets your window with the windows api then handles the bitmap that it generates with gdiplus and saves it to a file.

The screenshot header file
#include <Windows.h>
#include <gdiplus.h>


#pragma comment(lib, "gdiplus.lib")
#pragma once

class Screenshot
{
public:
    Screenshot();
    ~Screenshot();
    void makeScreenshot(const WCHAR*);
private:
    ULONG_PTR token;
    int GetEncoderClsid(const WCHAR*, CLSID*);
};

The screenshot class

#include "Screenshot.h"

ULONG_PTR gdiToken;

Screenshot::Screenshot()
{
    Gdiplus::GdiplusStartupInput StartupInput;
    Gdiplus::GdiplusStartup(&gdiToken, &StartupInput, NULL);
}


Screenshot::~Screenshot()
{
    Gdiplus::GdiplusShutdown(gdiToken);
}

int Screenshot::GetEncoderClsid(const WCHAR* format, CLSID* pClsid) {
    UINT num = 0;
    UINT size = 0;

    Gdiplus::ImageCodecInfo* pImageCodecInfo = NULL;
    Gdiplus::GetImageEncodersSize(&num, &size);
   
    if (size == 0)
        return -1;

    pImageCodecInfo = (Gdiplus::ImageCodecInfo*)(malloc(size));

    if (pImageCodecInfo == NULL)
        return -1;

    Gdiplus::GetImageEncoders(num, size, pImageCodecInfo);

    for (UINT codec = 0; codec < num; ++codec)
    {
        if (wcscmp(pImageCodecInfo[codec].MimeType, format) == 0)
        {
            *pClsid = pImageCodecInfo[codec].Clsid;
            free(pImageCodecInfo);
            return codec;
        }
    }

    free(pImageCodecInfo);
    return -1;
}

void Screenshot::makeScreenshot(const WCHAR* filename) {
    int screenHeight = GetSystemMetrics(SM_CYSCREEN);
    int screenWidth = GetSystemMetrics(SM_CXSCREEN);

    HWND desktopWindow = GetDesktopWindow();

    HDC desktopDC = GetDC(desktopWindow);
    HDC captureDC = CreateCompatibleDC(desktopDC);

    HBITMAP captureBitmap = CreateCompatibleBitmap(desktopDC, screenWidth, screenHeight);
    SelectObject(captureDC, captureBitmap);
    BitBlt(captureDC, 0, 0, screenWidth, screenHeight, desktopDC, 0, 0, SRCCOPY | CAPTUREBLT);

    Gdiplus::Bitmap *bitmap = new Gdiplus::Bitmap(captureBitmap, NULL);
    CLSID clsId;

    int retVal = this->GetEncoderClsid(L"image/png", &clsId);
    bitmap->Save(filename, &clsId, NULL);
   
    ReleaseDC(desktopWindow, desktopDC);
    DeleteDC(captureDC);
    DeleteObject(captureBitmap);
}


A little script I made that fits in my desktop workflow

#!/usr/bin/ruby

require 'rubygems'
require 'json'
require 'etc'
require 'net/http'
require 'fileutils'
require 'configparser'

class Weather
  def initialize(location, link)
    @location = location
    @link = link
    @data = get_data
  end

  def kelvin_to_celcius(kelvin)
    ((kelvin - 273.15) * 1).round.to_s
  end

  def get_data
    uri = URI(@link + @location)
    Net::HTTP.get(uri)
  end

  def get_degrees
    json = JSON.parse( @data )
    kelvin_to_celcius(json["main"]["temp_min"].to_i)
  end

  def to_s
    get_degrees + "°C In " + @location
  end
end

conf_dir = '/home/' + ENV['USER'] + '/.weatherdzen/'

unless File.exists? conf_dir
  FileUtils.mkpath conf_dir
  FileUtils.touch conf_dir + 'config'
 
  File.open(conf_dir + 'config', "w") do |f|
    f.puts('[basic]')
    f.puts('location=Antwerp')
    f.puts('notify=notifysend')
    f.close
  end
end

cfg = ConfigParser.new(conf_dir + 'config')

weather = Weather.new(
  cfg["basic"]["location"],
  "http://api.openweathermap.org/data/2.5/weather?q="
)

notifier = cfg["basic"]["notify"]
wtr =  weather.to_s

if notifier == "dzen"
  exec 'echo ' + wtr + '| dzen2 -title-name "brightness" -l 3 -bg "#263238" -fg "#b1fff8" -x 790 -y 480 -w 270 -h 70 -p 3 -e'
elsif notifier == "notifysend"
  exec 'notify-send "' + wtr + '"'
end


Needs  etc and configparser gems + dzen2 installed.

EDIT:autowrite config, autowrite based on users location coming later
EDIT2: for people with xfce and unity and any other DE that uses notify-send you can now use that and configure in the config file