added the possibility to rescale the image during loading, especially useful with...

[wxWidgets.git] / src / common / imagbmp.cpp

diff --git a/src/common/imagbmp.cpp b/src/common/imagbmp.cpp
index 66718fc518fb63bd974134aeeb4b9c4e4669527f..4ba94c276e1afafa00ee804570c6ee12469be081 100644 (file)
--- a/src/common/imagbmp.cpp
+++ b/src/common/imagbmp.cpp
@@ -33,6 +33,7 @@
 #include "wx/filefn.h"
 #include "wx/wfstream.h"
 #include "wx/quantize.h"
+#include "wx/scopeguard.h"
 #include "wx/anidecod.h"
 
 // For memcpy
@@ -194,8 +195,8 @@ bool wxBMPHandler::SaveDib(wxImage *image,
 
         case wxIMAGE_RESOLUTION_INCHES:
             // convert resolution in inches to resolution in centimeters
-            hres = (wxUint32)(100*mm2inches*hres);
-            vres = (wxUint32)(100*mm2inches*vres);
+            hres = (wxUint32)(10*mm2inches*hres);
+            vres = (wxUint32)(10*mm2inches*vres);
             // fall through to convert it to resolution in meters
 
         case wxIMAGE_RESOLUTION_CM:
@@ -469,18 +470,20 @@ bool wxBMPHandler::SaveDib(wxImage *image,
 }
 
 
-typedef struct
+struct BMPPalette
 {
+    static void Free(BMPPalette* pal) { delete [] pal; }
+
     unsigned char r, g, b;
-}  _cmap;
+};
 
 bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
                              int bpp, int ncolors, int comp,
                              wxFileOffset bmpOffset, wxInputStream& stream,
                              bool verbose, bool IsBmp, bool hasPalette)
 {
-    wxInt32         aDword, rmask = 0, gmask = 0, bmask = 0;
-    int             rshift = 0, gshift = 0, bshift = 0;
+    wxInt32         aDword, rmask = 0, gmask = 0, bmask = 0, amask = 0;
+    int             rshift = 0, gshift = 0, bshift = 0, ashift = 0;
     int             rbits = 0, gbits = 0, bbits = 0;
     wxInt32         dbuf[4];
     wxInt8          bbuf[4];
@@ -488,11 +491,11 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
     wxUint16        aWord;
 
     // allocate space for palette if needed:
-    _cmap *cmap;
+    BMPPalette *cmap;
 
     if ( bpp < 16 )
     {
-        cmap = new _cmap[ncolors];
+        cmap = new BMPPalette[ncolors];
         if ( !cmap )
         {
             if (verbose)
@@ -500,8 +503,12 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
             return false;
         }
     }
-    else
+    else // no palette
+    {
         cmap = NULL;
+    }
+
+    wxON_BLOCK_EXIT1(&BMPPalette::Free, cmap);
 
     // destroy existing here instead of:
     image->Destroy();
@@ -513,11 +520,27 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
     {
         if ( verbose )
             wxLogError( _("BMP: Couldn't allocate memory.") );
-        if ( cmap )
-            delete[] cmap;
         return false;
     }
 
+    unsigned char *alpha;
+    if ( bpp == 32 )
+    {
+        // tell the image to allocate an alpha buffer
+        image->SetAlpha();
+        alpha = image->GetAlpha();
+        if ( !alpha )
+        {
+            if ( verbose )
+                wxLogError(_("BMP: Couldn't allocate memory."));
+            return false;
+        }
+    }
+    else // no alpha
+    {
+        alpha = NULL;
+    }
+
     // Reading the palette, if it exists:
     if ( bpp < 16 && ncolors != 0 )
     {
@@ -602,6 +625,9 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
             rmask = 0x00FF0000;
             gmask = 0x0000FF00;
             bmask = 0x000000FF;
+            amask = 0xFF000000;
+
+            ashift = 24;
             rshift = 16;
             gshift = 8;
             bshift = 0;
@@ -840,6 +866,11 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
                 ptr[poffset + 1] = temp;
                 temp = (unsigned char)((aDword & bmask) >> bshift);
                 ptr[poffset + 2] = temp;
+                if ( alpha )
+                {
+                    temp = (unsigned char)((aDword & amask) >> ashift);
+                    alpha[line * width + column] = temp;
+                }
                 column++;
             }
         }
@@ -852,8 +883,6 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
         }
     }
 
-    delete[] cmap;
-
     image->SetMask(false);
 
     const wxStreamError err = stream.GetLastError();