Dynamically generating images in ISAPI extension using GDI+ with live demo

#include "StdAfx.h"
#include "gdipexample.h"
#include "GDIpISAPI.h"

void CGdipExample::SetSize(int iWidth,int iHeight)
{
	m_size = CSize( __max( 1, __min( 1024, iWidth)), __max( 1, __min( 1024, iHeight)) );  
}


void CGdipExample::DrawStuff(Gdiplus::Image& image)
{
	using namespace Gdiplus;
	USES_CONVERSION;
	CString str,str2;


	if (!m_pServer || !m_pCtxt)
		return;

	DWORD dwBuffer=1024;
	int w=image.GetWidth();
	int h= image.GetHeight();

	Graphics graphics(&image);

	// Create a Pen object.
	LinearGradientBrush white(
		Point(0, 0),	
		Point(w,h),
		Color(255, 255, 255),   // opaque red
		Color(220, 220, 220));  // opaque blue
	LinearGradientBrush redyellow(
		Point(0, 0),	
		Point(w,h),
		Color(0,0,255,0),   // opaque red
		Color(200, 255, 255,0));  // opaque blue

	SolidBrush blue(Color(0, 0, 50));
	Pen black(Color(0, 0, 0), 3);
	FontFamily  fontFamily(L"Tahoma");
	Font        font(&fontFamily, 14, FontStyleRegular, UnitPixel);

	graphics.FillRectangle(&white, 0,0,w, h);
	graphics.FillRectangle(&redyellow, 5,5,50, h-10);
	graphics.DrawRectangle(&black, 5,5,w-10, h-10);

	str+="This image has been generated by GDI+ (on the server)\r\n and sent to your browser using an ISAPI extension.\r\n\r\n";
	str+="Time/Date: "; str+=CTime::GetCurrentTime().Format("%b-%d-%Y, %H:%M:%S"); str+="\r\n";
	m_pCtxt->GetServerVariable(_T("REMOTE_HOST"), str2.GetBufferSetLength(dwBuffer), &dwBuffer);
	str2.ReleaseBuffer();
	str+="Client adress: "; str+=str2; str+="\r\n";
	str+="Type: "; str+=m_sImageType; str+="\r\n";
	str2.Format("%dx%d",w, h);
	str+="Size (pixels): "; str+=str2; str+="\r\n";
	str+="Method: "; str+=m_pCtxt->m_pECB->lpszMethod; str+="\r\n";
	str+="Coded by Jonathan de Halleux, dehalleux@auto.ucl.ac.be\r\n";
	LPWSTR lpwz = A2W(str);
	graphics.DrawString(lpwz, -1, &font, PointF((REAL)30, (REAL)30), &blue);
	graphics.Flush(  FlushIntentionFlush);
}


void CGdipExample::Render()
{
	CSingleLock lock(&m_mutex);
	lock.Lock();
	if (lock.IsLocked())
	{
		Gdiplus::Bitmap bitmap(m_size.cx, m_size.cy);

		DrawStuff(bitmap);
	
		CGDIpISAPI gdip(m_pServer, m_pCtxt, &bitmap);
	
		m_sImageType.MakeLower();
		if (m_sImageType=="jpeg" || m_sImageType=="jpg")
			gdip.SetImageType(CGDIpISAPI::ImageJPEG);
		else if (m_sImageType=="bmp")
			gdip.SetImageType(CGDIpISAPI::ImageBMP);
		else
			gdip.SetImageType(CGDIpISAPI::ImagePNG);
	
		gdip.WriteImage();
		
		lock.Unlock();
	}
}