]> git.saurik.com Git - wxWidgets.git/blobdiff - src/msw/dc.cpp
Implement wxWindowDC::Clear()
[wxWidgets.git] / src / msw / dc.cpp
index 8a05efa95c76f6b68e7d0206eff9e4e6c8ea2ba5..a795a51b5e0f52b20a7a0fd6b8d23fbd4d4acfdf 100644 (file)
@@ -5,7 +5,7 @@
 // Modified by:
 // Created:     01/02/97
 // RCS-ID:      $Id$
-// Copyright:   (c) Julian Smart and Markus Holzem
+// Copyright:   (c) Julian Smart
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 
 #include "wx/sysopt.h"
 #include "wx/dcprint.h"
 #include "wx/module.h"
+#include "wx/dynload.h"
+
+#ifdef wxHAVE_RAW_BITMAP
+#include "wx/rawbmp.h"
+#endif
 
 #include <string.h>
 #include <math.h>
     #include <print.h>
 #endif
 
+#ifndef AC_SRC_ALPHA
+#define AC_SRC_ALPHA 1
+#endif
+
 /* Quaternary raster codes */
 #ifndef MAKEROP4
 #define MAKEROP4(fore,back) (DWORD)((((back) << 8) & 0xFF000000) | (fore))
@@ -108,6 +117,25 @@ static const int MM_METRIC = 10;
 // convert degrees to radians
 static inline double DegToRad(double deg) { return (deg * M_PI) / 180.0; }
 
+// call AlphaBlend() to blit contents of hdcSrc to hdcDst using alpha
+//
+// NB: bmpSrc is the bitmap selected in hdcSrc, it is not really needed
+//     to pass it to this function but as we already have it at the point
+//     of call anyhow we do
+//
+// return true if we could draw the bitmap in one way or the other, false
+// otherwise
+static bool AlphaBlt(HDC hdcDst,
+                     int x, int y, int w, int h,
+                     HDC hdcSrc,
+                     const wxBitmap& bmpSrc);
+
+#ifdef wxHAVE_RAW_BITMAP
+// our (limited) AlphaBlend() replacement
+static void
+wxAlphaBlend(HDC hdcDst, int x, int y, int w, int h, const wxBitmap& bmp);
+#endif
+
 // ----------------------------------------------------------------------------
 // private classes
 // ----------------------------------------------------------------------------
@@ -272,10 +300,12 @@ void wxDC::SelectOldObjects(WXHDC dc)
         if (m_oldBitmap)
         {
             ::SelectObject((HDC) dc, (HBITMAP) m_oldBitmap);
+#ifdef __WXDEBUG__
             if (m_selectedBitmap.Ok())
             {
                 m_selectedBitmap.SetSelectedInto(NULL);
             }
+#endif
         }
         m_oldBitmap = 0;
         if (m_oldPen)
@@ -644,7 +674,7 @@ void wxDC::DoDrawCheckMark(wxCoord x1, wxCoord y1,
     wxCoord x2 = x1 + width,
             y2 = y1 + height;
 
-#if defined(__WIN32__) && !defined(__SC__) && !defined(__WXMICROWIN__)
+#if defined(__WIN32__) && !defined(__SYMANTEC__) && !defined(__WXMICROWIN__)
     RECT rect;
     rect.left   = x1;
     rect.top    = y1;
@@ -939,6 +969,15 @@ void wxDC::DoDrawBitmap( const wxBitmap &bmp, wxCoord x, wxCoord y, bool useMask
     HPALETTE oldPal = 0;
 #endif // wxUSE_PALETTE
 
+    if ( bmp.HasAlpha() )
+    {
+        MemoryHDC hdcMem;
+        SelectInHDC select(hdcMem, GetHbitmapOf(bmp));
+
+        if ( AlphaBlt(GetHdc(), x, y, width, height, hdcMem, bmp) )
+            return;
+    }
+
     if ( useMask )
     {
         wxMask *mask = bmp.GetMask();
@@ -1360,40 +1399,9 @@ void wxDC::SetBackground(const wxBrush& brush)
 
     m_backgroundBrush = brush;
 
-    if (!m_backgroundBrush.Ok())
-        return;
-
-    if (m_canvas)
+    if ( m_backgroundBrush.Ok() )
     {
-        bool customColours = TRUE;
-        // If we haven't specified wxUSER_COLOURS, don't allow the panel/dialog box to
-        // change background colours from the control-panel specified colours.
-        if (m_canvas->IsKindOf(CLASSINFO(wxWindow)) && ((m_canvas->GetWindowStyleFlag() & wxUSER_COLOURS) != wxUSER_COLOURS))
-            customColours = FALSE;
-
-        if (customColours)
-        {
-            if (m_backgroundBrush.GetStyle()==wxTRANSPARENT)
-            {
-                m_canvas->SetTransparent(TRUE);
-            }
-            else
-            {
-                // New behaviour, 10/2/99: setting the background brush of a DC
-                // doesn't affect the window background colour. However,
-                // I'm leaving in the transparency setting because it's needed by
-                // various controls (e.g. wxStaticText) to determine whether to draw
-                // transparently or not. TODO: maybe this should be a new function
-                // wxWindow::SetTransparency(). Should that apply to the child itself, or the
-                // parent?
-                //        m_canvas->SetBackgroundColour(m_backgroundBrush.GetColour());
-                m_canvas->SetTransparent(FALSE);
-            }
-        }
-    }
-    COLORREF new_color = m_backgroundBrush.GetColour().GetPixel();
-    {
-        (void)SetBkColor(GetHdc(), new_color);
+        (void)SetBkColor(GetHdc(), m_backgroundBrush.GetColour().GetPixel());
     }
 }
 
@@ -1576,8 +1584,8 @@ void wxDC::SetMapMode(int mode)
             return;
         }
 
-        double mm2pixelsX = pixel_width / mm_width,
-               mm2pixelsY = pixel_height / mm_height;
+        double mm2pixelsX = (double)pixel_width / mm_width,
+               mm2pixelsY = (double)pixel_height / mm_height;
 
         switch (mode)
         {
@@ -1757,17 +1765,26 @@ bool wxDC::DoBlit(wxCoord xdest, wxCoord ydest,
                   int rop, bool useMask,
                   wxCoord xsrcMask, wxCoord ysrcMask)
 {
+    wxCHECK_MSG( source, FALSE, _T("wxDC::Blit(): NULL wxDC pointer") );
+
 #ifdef __WXMICROWIN__
     if (!GetHDC()) return FALSE;
 #endif
 
+    const wxBitmap& bmpSrc = source->m_selectedBitmap;
+    if ( bmpSrc.Ok() && bmpSrc.HasAlpha() )
+    {
+        if ( AlphaBlt(GetHdc(), xdest, ydest, width, height,
+                      GetHdcOf(*source), bmpSrc) )
+            return TRUE;
+    }
+
     wxMask *mask = NULL;
     if ( useMask )
     {
-        const wxBitmap& bmp = source->m_selectedBitmap;
-        mask = bmp.GetMask();
+        mask = bmpSrc.GetMask();
 
-        if ( !(bmp.Ok() && mask && mask->GetMaskBitmap()) )
+        if ( !(bmpSrc.Ok() && mask && mask->GetMaskBitmap()) )
         {
             // don't give assert here because this would break existing
             // programs - just silently ignore useMask parameter
@@ -1931,36 +1948,79 @@ bool wxDC::DoBlit(wxCoord xdest, wxCoord ydest,
     }
     else // no mask, just BitBlt() it
     {
-        // use StretchBlt() if available
-        if ( ::GetDeviceCaps(GetHdc(), RASTERCAPS) & RC_STRETCHBLT )
+        // if we already have a DIB, draw it using StretchDIBits(), otherwise
+        // use StretchBlt() if available and finally fall back to BitBlt()
+        const int caps = ::GetDeviceCaps(GetHdc(), RASTERCAPS);
+        if ( bmpSrc.Ok() && (caps & RC_STRETCHDIB) )
         {
-            StretchBltModeChanger changeMode(GetHdc(), COLORONCOLOR);
+            DIBSECTION ds;
+            wxZeroMemory(ds);
 
-            success = ::StretchBlt
-                        (
-                            GetHdc(),
-                            xdest, ydest, width, height,
-                            GetHdcOf(*source),
-                            xsrc, ysrc, width, height,
-                            dwRop
-                        ) != 0;
+            if ( ::GetObject(GetHbitmapOf(bmpSrc),
+                             sizeof(ds),
+                             &ds) == sizeof(ds) )
+            {
+                StretchBltModeChanger changeMode(GetHdc(), COLORONCOLOR);
+
+                if ( ::StretchDIBits(GetHdc(),
+                                     xdest, ydest,
+                                     width, height,
+                                     0, 0,
+                                     width, height,
+                                     ds.dsBm.bmBits,
+                                     (LPBITMAPINFO)&ds.dsBmih,
+                                     DIB_RGB_COLORS,
+                                     SRCCOPY
+                                     ) == (int)GDI_ERROR )
+                {
+                    wxLogLastError(wxT("StretchDIBits"));
+                }
+                else
+                {
+                    success = TRUE;
+                }
+            }
         }
-        else
+
+        if ( !success && (caps & RC_STRETCHBLT) )
         {
-            success = ::BitBlt
-                        (
-                            GetHdc(),
-                            xdest, ydest,
-                            (int)width, (int)height,
-                            GetHdcOf(*source),
-                            xsrc, ysrc,
-                            dwRop
-                        ) != 0;
+            StretchBltModeChanger changeMode(GetHdc(), COLORONCOLOR);
+
+            if ( !::StretchBlt
+                    (
+                        GetHdc(),
+                        xdest, ydest, width, height,
+                        GetHdcOf(*source),
+                        xsrc, ysrc, width, height,
+                        dwRop
+                    ) )
+            {
+                wxLogLastError(_T("StretchBlt"));
+            }
+            else
+            {
+                success = TRUE;
+            }
         }
 
         if ( !success )
         {
-            wxLogLastError(wxT("BitBlt/StretchBlt"));
+            if ( !::BitBlt
+                    (
+                        GetHdc(),
+                        xdest, ydest,
+                        (int)width, (int)height,
+                        GetHdcOf(*source),
+                        xsrc, ysrc,
+                        dwRop
+                    ) )
+            {
+                wxLogLastError(_T("BitBlt"));
+            }
+            else
+            {
+                success = TRUE;
+            }
         }
     }
 
@@ -2035,6 +2095,10 @@ void wxDC::SetLogicalScale(double x, double y)
     m_logicalScaleY = y;
 }
 
+// ----------------------------------------------------------------------------
+// DC caching
+// ----------------------------------------------------------------------------
+
 #if wxUSE_DC_CACHEING
 
 /*
@@ -2075,10 +2139,10 @@ wxDCCacheEntry::~wxDCCacheEntry()
 wxDCCacheEntry* wxDC::FindBitmapInCache(WXHDC dc, int w, int h)
 {
     int depth = ::GetDeviceCaps((HDC) dc, PLANES) * ::GetDeviceCaps((HDC) dc, BITSPIXEL);
-    wxNode* node = sm_bitmapCache.First();
+    wxNode* node = sm_bitmapCache.GetFirst();
     while (node)
     {
-        wxDCCacheEntry* entry = (wxDCCacheEntry*) node->Data();
+        wxDCCacheEntry* entry = (wxDCCacheEntry*) node->GetData();
 
         if (entry->m_depth == depth)
         {
@@ -2096,7 +2160,7 @@ wxDCCacheEntry* wxDC::FindBitmapInCache(WXHDC dc, int w, int h)
             return entry;
         }
 
-        node = node->Next();
+        node = node->GetNext();
     }
     WXHBITMAP hBitmap = (WXHBITMAP) ::CreateCompatibleBitmap((HDC) dc, w, h);
     if ( !hBitmap)
@@ -2111,10 +2175,10 @@ wxDCCacheEntry* wxDC::FindBitmapInCache(WXHDC dc, int w, int h)
 wxDCCacheEntry* wxDC::FindDCInCache(wxDCCacheEntry* notThis, WXHDC dc)
 {
     int depth = ::GetDeviceCaps((HDC) dc, PLANES) * ::GetDeviceCaps((HDC) dc, BITSPIXEL);
-    wxNode* node = sm_dcCache.First();
+    wxNode* node = sm_dcCache.GetFirst();
     while (node)
     {
-        wxDCCacheEntry* entry = (wxDCCacheEntry*) node->Data();
+        wxDCCacheEntry* entry = (wxDCCacheEntry*) node->GetData();
 
         // Don't return the same one as we already have
         if (!notThis || (notThis != entry))
@@ -2125,7 +2189,7 @@ wxDCCacheEntry* wxDC::FindDCInCache(wxDCCacheEntry* notThis, WXHDC dc)
             }
         }
 
-        node = node->Next();
+        node = node->GetNext();
     }
     WXHDC hDC = (WXHDC) ::CreateCompatibleDC((HDC) dc);
     if ( !hDC)
@@ -2170,6 +2234,143 @@ private:
 
 IMPLEMENT_DYNAMIC_CLASS(wxDCModule, wxModule)
 
-#endif
-    // wxUSE_DC_CACHEING
+#endif // wxUSE_DC_CACHEING
+
+// ----------------------------------------------------------------------------
+// alpha channel support
+// ----------------------------------------------------------------------------
+
+static bool AlphaBlt(HDC hdcDst,
+                     int x, int y, int width, int height,
+                     HDC hdcSrc,
+                     const wxBitmap& bmp)
+{
+    wxASSERT_MSG( bmp.Ok() && bmp.HasAlpha(), _T("AlphaBlt(): invalid bitmap") );
+    wxASSERT_MSG( hdcDst && hdcSrc, _T("AlphaBlt(): invalid HDC") );
+
+    // do we have AlphaBlend() and company in the headers?
+#if defined(AC_SRC_OVER) && wxUSE_DYNLIB_CLASS
+    // yes, now try to see if we have it during run-time
+    typedef BOOL (WINAPI *AlphaBlend_t)(HDC,int,int,int,int,
+                                        HDC,int,int,int,int,
+                                        BLENDFUNCTION);
+
+    // bitmaps can be drawn only from GUI thread so there is no need to
+    // protect this static variable from multiple threads
+    static bool s_triedToLoad = FALSE;
+    static AlphaBlend_t pfnAlphaBlend = NULL;
+    if ( !s_triedToLoad )
+    {
+        s_triedToLoad = TRUE;
+
+        // don't give errors about the DLL being unavailable, we're
+        // prepared to handle this
+        wxLogNull nolog;
+
+        wxDynamicLibrary dll(_T("msimg32.dll"));
+        if ( dll.IsLoaded() )
+        {
+            pfnAlphaBlend = (AlphaBlend_t)dll.GetSymbol(_T("AlphaBlend"));
+            if ( pfnAlphaBlend )
+            {
+                // we must keep the DLL loaded if we want to be able to
+                // call AlphaBlend() so just never unload it at all, not a
+                // big deal
+                dll.Detach();
+            }
+        }
+    }
+
+    if ( pfnAlphaBlend )
+    {
+        BLENDFUNCTION bf;
+        bf.BlendOp = AC_SRC_OVER;
+        bf.BlendFlags = 0;
+        bf.SourceConstantAlpha = 0xff;
+        bf.AlphaFormat = AC_SRC_ALPHA;
+
+        if ( pfnAlphaBlend(hdcDst, x, y, width, height,
+                           hdcSrc, 0, 0, width, height,
+                           bf) )
+        {
+            // skip wxAlphaBlend() call below
+            return TRUE;
+        }
+
+        wxLogLastError(_T("AlphaBlend"));
+    }
+#endif // defined(AC_SRC_OVER)
+
+    // AlphaBlend() unavailable of failed: use our own (probably much slower)
+    // implementation
+#ifdef wxHAVE_RAW_BITMAP
+    wxAlphaBlend(hdcDst, x, y, width, height, bmp);
+
+    return TRUE;
+#else // !wxHAVE_RAW_BITMAP
+    // no wxAlphaBlend() neither, fall back to using simple BitBlt() (we lose
+    // alpha but at least something will be shown like this)
+    return FALSE;
+#endif // wxHAVE_RAW_BITMAP
+}
+
+
+// wxAlphaBlend: our fallback if ::AlphaBlend() is unavailable
+#ifdef wxHAVE_RAW_BITMAP
+
+static void
+wxAlphaBlend(HDC hdcDst, int xDst, int yDst, int w, int h, const wxBitmap& bmpSrc)
+{
+    // get the destination DC pixels
+    wxBitmap bmpDst(w, h, 32 /* force creating RGBA DIB */);
+    MemoryHDC hdcMem;
+    SelectInHDC select(hdcMem, GetHbitmapOf(bmpDst));
+
+    if ( !::BitBlt(hdcMem, 0, 0, w, h, hdcDst, 0, 0, SRCCOPY) )
+    {
+        wxLogLastError(_T("BitBlt"));
+    }
+
+    // combine them with the source bitmap using alpha
+    wxAlphaPixelData dataDst(bmpDst),
+                     dataSrc((wxBitmap &)bmpSrc);
+
+    wxCHECK_RET( dataDst && dataSrc,
+                    _T("failed to get raw data in wxAlphaBlend") );
+
+    wxAlphaPixelData::Iterator pDst(dataDst),
+                               pSrc(dataSrc);
+
+    for ( int y = 0; y < h; y++ )
+    {
+        wxAlphaPixelData::Iterator pDstRowStart = pDst,
+                                   pSrcRowStart = pSrc;
+
+        for ( int x = 0; x < w; x++ )
+        {
+            // note that source bitmap uses premultiplied alpha (as required by
+            // the real AlphaBlend)
+            const unsigned beta = 255 - pSrc.Alpha();
+
+            pDst.Red() = pSrc.Red() + (beta * pDst.Red() + 127) / 255;
+            pDst.Blue() = pSrc.Blue() + (beta * pDst.Blue() + 127) / 255;
+            pDst.Green() = pSrc.Green() + (beta * pDst.Green() + 127) / 255;
+
+            ++pDst;
+            ++pSrc;
+        }
+
+        pDst = pDstRowStart;
+        pSrc = pSrcRowStart;
+        pDst.OffsetY(dataDst, 1);
+        pSrc.OffsetY(dataSrc, 1);
+    }
+
+    // and finally blit them back to the destination DC
+    if ( !::BitBlt(hdcDst, xDst, yDst, w, h, hdcMem, 0, 0, SRCCOPY) )
+    {
+        wxLogLastError(_T("BitBlt"));
+    }
+}
 
+#endif // #ifdef wxHAVE_RAW_BITMAP