optimized drawing of bitmaps in viewer

ImageViewer.cpp

@@ -1,232 +1,234 @@
-// ImageViewer.cpp : implementation file
-//
-
-#include "stdafx.h"
-#include "CP_Main.h"
-#include "ImageViewer.h"
-#include "BitmapHelper.h"
-
-
-// CImageViewer
-
-IMPLEMENT_DYNAMIC(CImageViewer, CWnd)
-
-CImageViewer::CImageViewer()
-{
-	m_scrollHelper.AttachWnd(this);
-	m_hoveringOverImage = false;
-	m_pGdiplusBitmap = NULL;
-}
-
-CImageViewer::~CImageViewer()
-{
-	delete m_pGdiplusBitmap;
-}
-
-
-BEGIN_MESSAGE_MAP(CImageViewer, CWnd)
-	ON_WM_HSCROLL()
-	ON_WM_VSCROLL()
-	ON_WM_MOUSEWHEEL()
-	ON_WM_PAINT()
-	ON_WM_SIZE()
-	ON_WM_SETCURSOR()
-	ON_WM_LBUTTONUP()
-	ON_WM_MOUSEHWHEEL()
-END_MESSAGE_MAP()
-
-BOOL CImageViewer::Create(CWnd* pParent)
-{
-	BOOL bSuccess;
-
-	// Register window class
-	CString csClassName = AfxRegisterWndClass(CS_OWNDC | CS_HREDRAW | CS_VREDRAW,
-		LoadCursor(NULL, IDC_ARROW),
-		CBrush(::GetSysColor(COLOR_BTNFACE)));
-
-
-
-	// If no parent supplied then try and get a pointer to it anyway
-	if (!pParent)
-		pParent = AfxGetMainWnd();
-
-	// Create popup window
-	//bSuccess = CreateEx(WS_EX_DLGMODALFRAME|WS_EX_TOPMOST, // Extended style
-	bSuccess = CreateEx(0,
-		csClassName,                       // Classname
-		_T(""),                          // Title
-		WS_CHILD | WS_VISIBLE | WS_VSCROLL | WS_HSCROLL,     // style
-		0, 0,                               // position - updated soon.
-		390, 130,                           // Size - updated soon
-		pParent->GetSafeHwnd(),            // handle to parent
-		0,                                 // No menu
-		NULL);
-	if (!bSuccess) return FALSE;
-
-
-
-	return TRUE;
-}
-
-void CImageViewer::UpdateBitmapSize()
-{
-	if (m_pGdiplusBitmap != NULL)
-	{
-		if (CGetSetOptions::GetScaleImagesToDescWindow())
-		{
-			CRect rect;
-			GetClientRect(rect);
-
-			m_scrollHelper.SetDisplaySize(0, 0);
-			m_scrollHelper.DetachWnd();
-			
-		}
-		else
-		{
-			m_scrollHelper.AttachWnd(this);
-			m_scrollHelper.SetDisplaySize(m_pGdiplusBitmap->GetWidth(), m_pGdiplusBitmap->GetHeight());
-		}
-	}
-}
-
-void CImageViewer::OnPaint()
-{
-	CPaintDC dc(this); // device context for painting
-
-	CRect rect;
-	GetClientRect(rect);	
-
-	CBrush  Brush, *pOldBrush;
-	Brush.CreateSolidBrush(g_Opt.m_Theme.DescriptionWindowBG());
-
-	pOldBrush = dc.SelectObject(&Brush);
-
-	dc.FillRect(&rect, &Brush);
-
-	if (m_pGdiplusBitmap)
-	{
-		int width = m_pGdiplusBitmap->GetWidth();
-		int height = m_pGdiplusBitmap->GetHeight();
-		
-		if (CGetSetOptions::GetScaleImagesToDescWindow())
-		{
-			double newWidth = rect.Width();
-			double newHeight = rect.Height();
-
-			if (width > 0 &&
-				height > 0 &&
-				rect.Width() > 0 &&
-				rect.Height() > 0)
-			{
-				float origAspect = (width / (float)height);
-				float newAspect = (rect.Width() / (float)rect.Height());
-
-				if (origAspect > newAspect)
-				{
-					newHeight = (rect.Width() * height) / width;
-				}
-				else
-				{
-					newWidth = (rect.Height() * width) / height;
-				}
-			}
-
-			Gdiplus::ImageAttributes attrs;
-			Gdiplus::Rect dest(0, 0, (int)newWidth, (int)newHeight);
-
-			Gdiplus::Graphics graphics(dc);
-			graphics.SetInterpolationMode(Gdiplus::InterpolationModeHighQualityBicubic);
-			graphics.SetPixelOffsetMode(Gdiplus::PixelOffsetModeHalf);
-
-			graphics.DrawImage(m_pGdiplusBitmap, dest, 0, 0, width, height, Gdiplus::UnitPixel, &attrs);
-
-
-		}
-		else
-		{
-			CSize s = m_scrollHelper.GetScrollPos();
-			Gdiplus::Graphics graphics(dc);
-			graphics.DrawImage(m_pGdiplusBitmap, rect.left, rect.top, s.cx, s.cy, width, height, Gdiplus::UnitPixel);
-
-			//dc.BitBlt(rect.left, rect.top, width, height, &MemDc, s.cx, s.cy, SRCCOPY);
-		}
-		
-		rect.top += height;
-	}
-	
-	// Cleanup
-	dc.SelectObject(pOldBrush);
-}
-
-
-void CImageViewer::OnHScroll(UINT nSBCode, UINT nPos, CScrollBar* pScrollBar)
-{
-	m_scrollHelper.OnHScroll(nSBCode, nPos, pScrollBar);
-}
-
-void CImageViewer::OnVScroll(UINT nSBCode, UINT nPos, CScrollBar* pScrollBar)
-{
-	m_scrollHelper.OnVScroll(nSBCode, nPos, pScrollBar);
-}
-
-BOOL CImageViewer::OnMouseWheel(UINT nFlags, short zDelta, CPoint pt)
-{
-	BOOL wasScrolled = m_scrollHelper.OnMouseWheel(nFlags, zDelta, pt);
-	return wasScrolled;
-}
-
-void CImageViewer::OnMouseHWheel(UINT nFlags, short zDelta, CPoint pt)
-{
-	BOOL wasScrolled = m_scrollHelper.OnMouseHWheel(nFlags, zDelta, pt);
-
-	CWnd::OnMouseHWheel(nFlags, zDelta, pt);
-}
-
-void CImageViewer::OnSize(UINT nType, int cx, int cy)
-{
-	CWnd::OnSize(nType, cx, cy);
-	m_scrollHelper.OnSize(nType, cx, cy);
-}
-
-BOOL CImageViewer::OnSetCursor(CWnd* pWnd, UINT nHitTest, UINT message)
-{
-	if (this->m_pGdiplusBitmap &&
-		pWnd->m_hWnd == this->m_hWnd &&
-		nHitTest == HTCLIENT)
-	{
-		if (CGetSetOptions::GetScaleImagesToDescWindow())
-		{
-			::SetCursor(AfxGetApp()->LoadCursor(IDC_CURSOR_ZOOM_IN));
-		}
-		else
-		{
-			::SetCursor(AfxGetApp()->LoadCursor(IDC_CURSOR_ZOOM_OUT));
-		}
-
-		m_hoveringOverImage = true;
-
-		return TRUE;
-	}
-
-	m_hoveringOverImage = false;
-
-	return CWnd::OnSetCursor(pWnd, nHitTest, message);
-}
-
-
-void CImageViewer::OnLButtonUp(UINT nFlags, CPoint point)
-{
-	if (this->m_pGdiplusBitmap &&
-		m_hoveringOverImage)
-	{
-		CGetSetOptions::SetScaleImagesToDescWindow(!CGetSetOptions::GetScaleImagesToDescWindow());
-		this->UpdateBitmapSize();
-		Invalidate();
-		return;
-	}
-
-	CWnd::OnLButtonUp(nFlags, point);
-}
-
-
-
+// ImageViewer.cpp : implementation file
+//
+
+#include "stdafx.h"
+#include "CP_Main.h"
+#include "ImageViewer.h"
+#include "BitmapHelper.h"
+#include "memdc.h"
+
+
+// CImageViewer
+
+IMPLEMENT_DYNAMIC(CImageViewer, CWnd)
+
+CImageViewer::CImageViewer()
+{
+	m_scrollHelper.AttachWnd(this);
+	m_hoveringOverImage = false;
+	m_pGdiplusBitmap = NULL;
+}
+
+CImageViewer::~CImageViewer()
+{
+	delete m_pGdiplusBitmap;
+}
+
+
+BEGIN_MESSAGE_MAP(CImageViewer, CWnd)
+	ON_WM_HSCROLL()
+	ON_WM_VSCROLL()
+	ON_WM_MOUSEWHEEL()
+	ON_WM_PAINT()
+	ON_WM_SIZE()
+	ON_WM_SETCURSOR()
+	ON_WM_LBUTTONUP()
+	ON_WM_MOUSEHWHEEL()
+END_MESSAGE_MAP()
+
+BOOL CImageViewer::Create(CWnd* pParent)
+{
+	BOOL bSuccess;
+
+	// Register window class
+	CString csClassName = AfxRegisterWndClass(CS_OWNDC | CS_HREDRAW | CS_VREDRAW,
+		LoadCursor(NULL, IDC_ARROW),
+		CBrush(::GetSysColor(COLOR_BTNFACE)));
+
+
+
+	// If no parent supplied then try and get a pointer to it anyway
+	if (!pParent)
+		pParent = AfxGetMainWnd();
+
+	// Create popup window
+	//bSuccess = CreateEx(WS_EX_DLGMODALFRAME|WS_EX_TOPMOST, // Extended style
+	bSuccess = CreateEx(0,
+		csClassName,                       // Classname
+		_T(""),                          // Title
+		WS_CHILD | WS_VISIBLE | WS_VSCROLL | WS_HSCROLL,     // style
+		0, 0,                               // position - updated soon.
+		390, 130,                           // Size - updated soon
+		pParent->GetSafeHwnd(),            // handle to parent
+		0,                                 // No menu
+		NULL);
+	if (!bSuccess) return FALSE;
+
+
+
+	return TRUE;
+}
+
+void CImageViewer::UpdateBitmapSize()
+{
+	if (m_pGdiplusBitmap != NULL)
+	{
+		if (CGetSetOptions::GetScaleImagesToDescWindow())
+		{
+			CRect rect;
+			GetClientRect(rect);
+
+			m_scrollHelper.SetDisplaySize(0, 0);
+			m_scrollHelper.DetachWnd();
+			
+		}
+		else
+		{
+			m_scrollHelper.AttachWnd(this);
+			m_scrollHelper.SetDisplaySize(m_pGdiplusBitmap->GetWidth(), m_pGdiplusBitmap->GetHeight());
+		}
+	}
+}
+
+void CImageViewer::OnPaint()
+{
+	CPaintDC dc(this); // device context for painting
+
+	CMemDCEx memDC(&dc);
+
+	CRect rect;
+	GetClientRect(rect);	
+
+	CBrush  Brush, *pOldBrush;
+	Brush.CreateSolidBrush(g_Opt.m_Theme.DescriptionWindowBG());
+
+	pOldBrush = memDC.SelectObject(&Brush);
+
+	memDC.FillRect(&rect, &Brush);
+
+	if (m_pGdiplusBitmap)
+	{
+		int width = m_pGdiplusBitmap->GetWidth();
+		int height = m_pGdiplusBitmap->GetHeight();
+		
+		if (CGetSetOptions::GetScaleImagesToDescWindow())
+		{
+
+			double newWidth = rect.Width();
+			double newHeight = rect.Height();
+
+			if (width > 0 &&
+				height > 0 &&
+				rect.Width() > 0 &&
+				rect.Height() > 0)
+			{
+				float origAspect = (width / (float)height);
+				float newAspect = (rect.Width() / (float)rect.Height());
+
+				if (origAspect > newAspect)
+				{
+					newHeight = (rect.Width() * height) / width;
+				}
+				else
+				{
+					newWidth = (rect.Height() * width) / height;
+				}
+			}
+
+			Gdiplus::ImageAttributes attrs;
+			Gdiplus::Rect dest(0, 0, (int)newWidth, (int)newHeight);
+
+			Gdiplus::Graphics graphics(memDC);
+			graphics.SetInterpolationMode(Gdiplus::InterpolationModeHighQualityBicubic);
+			graphics.SetPixelOffsetMode(Gdiplus::PixelOffsetModeHalf);
+
+			graphics.DrawImage(m_pGdiplusBitmap, dest, 0, 0, width, height, Gdiplus::UnitPixel, &attrs);
+
+
+		}
+		else
+		{
+
+			CSize s = m_scrollHelper.GetScrollPos();
+			Gdiplus::Graphics graphics(memDC);
+			graphics.DrawImage(m_pGdiplusBitmap, rect.left, rect.top, s.cx, s.cy, width, height, Gdiplus::UnitPixel);
+		}
+		
+		rect.top += height;
+	}
+	
+	memDC.SelectObject(pOldBrush);
+}
+
+
+void CImageViewer::OnHScroll(UINT nSBCode, UINT nPos, CScrollBar* pScrollBar)
+{
+	m_scrollHelper.OnHScroll(nSBCode, nPos, pScrollBar);
+}
+
+void CImageViewer::OnVScroll(UINT nSBCode, UINT nPos, CScrollBar* pScrollBar)
+{
+	m_scrollHelper.OnVScroll(nSBCode, nPos, pScrollBar);
+}
+
+BOOL CImageViewer::OnMouseWheel(UINT nFlags, short zDelta, CPoint pt)
+{
+	BOOL wasScrolled = m_scrollHelper.OnMouseWheel(nFlags, zDelta, pt);
+	return wasScrolled;
+}
+
+void CImageViewer::OnMouseHWheel(UINT nFlags, short zDelta, CPoint pt)
+{
+	BOOL wasScrolled = m_scrollHelper.OnMouseHWheel(nFlags, zDelta, pt);
+
+	CWnd::OnMouseHWheel(nFlags, zDelta, pt);
+}
+
+void CImageViewer::OnSize(UINT nType, int cx, int cy)
+{
+	CWnd::OnSize(nType, cx, cy);
+	m_scrollHelper.OnSize(nType, cx, cy);
+}
+
+BOOL CImageViewer::OnSetCursor(CWnd* pWnd, UINT nHitTest, UINT message)
+{
+	if (this->m_pGdiplusBitmap &&
+		pWnd->m_hWnd == this->m_hWnd &&
+		nHitTest == HTCLIENT)
+	{
+		if (CGetSetOptions::GetScaleImagesToDescWindow())
+		{
+			::SetCursor(AfxGetApp()->LoadCursor(IDC_CURSOR_ZOOM_IN));
+		}
+		else
+		{
+			::SetCursor(AfxGetApp()->LoadCursor(IDC_CURSOR_ZOOM_OUT));
+		}
+
+		m_hoveringOverImage = true;
+
+		return TRUE;
+	}
+
+	m_hoveringOverImage = false;
+
+	return CWnd::OnSetCursor(pWnd, nHitTest, message);
+}
+
+
+void CImageViewer::OnLButtonUp(UINT nFlags, CPoint point)
+{
+	if (this->m_pGdiplusBitmap &&
+		m_hoveringOverImage)
+	{
+		CGetSetOptions::SetScaleImagesToDescWindow(!CGetSetOptions::GetScaleImagesToDescWindow());
+		this->UpdateBitmapSize();
+		Invalidate();
+		return;
+	}
+
+	CWnd::OnLButtonUp(nFlags, point);
+}
+
+
+