X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/e4b8154a65be71ca58edf394546b19b0d3516438..9dc1d18069c519c807c2476a837e710b5ef932c6:/src/common/imagpcx.cpp?ds=sidebyside

diff --git a/src/common/imagpcx.cpp b/src/common/imagpcx.cpp
index e203698796..58eb0034c2 100644
--- a/src/common/imagpcx.cpp
+++ b/src/common/imagpcx.cpp
@@ -2,17 +2,12 @@
 // Name:        imagpcx.cpp
 // Purpose:     wxImage PCX handler
 // Author:      Guillermo Rodriguez Garcia <guille@iies.es>
-// Version:     1.00
+// Version:     1.1
 // CVS-ID:      $Id$
 // Copyright:   (c) 1999 Guillermo Rodriguez Garcia
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 
-/*
-   We don't put pragma implement in this file because it is already present in
-   src/common/image.cpp
-*/
-
 // For compilers that support precompilation, includes "wx.h".
 #include "wx/wxprec.h"
 
@@ -22,22 +17,74 @@
 
 #ifndef WX_PRECOMP
 #  include "wx/defs.h"
+#  include "wx/palette.h"
 #endif
 
-#if wxUSE_STREAMS && wxUSE_PCX
+#if wxUSE_IMAGE && wxUSE_PCX
 
-#include "wx/image.h"
+#include "wx/imagpcx.h"
 #include "wx/wfstream.h"
 #include "wx/module.h"
 #include "wx/log.h"
 #include "wx/intl.h"
 
+#include "wx/hash.h"
+#include "wx/list.h"
+#include "wx/object.h"
+
+//-----------------------------------------------------------------------------
+// wxPCXHandler
+//-----------------------------------------------------------------------------
+
+IMPLEMENT_DYNAMIC_CLASS(wxPCXHandler,wxImageHandler)
+
+#if wxUSE_STREAMS
+
 //-----------------------------------------------------------------------------
-// PCX decoding
+// RLE encoding and decoding
 //-----------------------------------------------------------------------------
 
-void RLEencode(unsigned char *WXUNUSED(p), unsigned int WXUNUSED(size), wxOutputStream& WXUNUSED(s))
+void RLEencode(unsigned char *p, unsigned int size, wxOutputStream& s)
 {
+    unsigned int data, last, cont;
+
+    // Write 'size' bytes. The PCX official specs say there will be
+    // a decoding break at the end of each scanline, so in order to
+    // force this decoding break use this function to write, at most,
+    // _one_ complete scanline at a time.
+
+    last = (unsigned char) *(p++);
+    cont = 1;
+    size--;
+
+    while (size-- > 0)
+    {
+        data = (unsigned char) *(p++);
+
+        // Up to 63 bytes with the same value can be stored using
+        // a single { cont, value } pair.
+        //
+        if ((data == last) && (cont < 63))
+        {
+            cont++;
+        }
+        else
+        {
+            // need to write a 'counter' byte?
+            if ((cont > 1) || ((last & 0xC0) == 0xC0))
+                s.PutC((char) (cont | 0xC0));
+
+            s.PutC((char) last);
+            last = data;
+            cont = 1;
+        }
+    }
+
+    // write the last one and return;
+    if ((cont > 1) || ((last & 0xC0) == 0xC0))
+        s.PutC((char) (cont | 0xC0));
+
+    s.PutC((char) last);
 }
 
 void RLEdecode(unsigned char *p, unsigned int size, wxInputStream& s)
@@ -49,7 +96,7 @@ void RLEdecode(unsigned char *p, unsigned int size, wxInputStream& s)
     // end of each plane inside a scanline). Only use this function
     // to read one or more _complete_ scanlines. Else, more than
     // 'size' bytes might be read and the buffer might overflow.
-    //
+
     while (size > 0)
     {
         data = (unsigned char)s.GetC();
@@ -57,10 +104,10 @@ void RLEdecode(unsigned char *p, unsigned int size, wxInputStream& s)
         // If ((data & 0xC0) != 0xC0), then the value read is a data
         // byte. Else, it is a counter (cont = val & 0x3F) and the
         // next byte is the data byte.
-        //
+
         if ((data & 0xC0) != 0xC0)
         {
-            *(p++) = data;
+            *(p++) = (unsigned char)data;
             size--;
         }
         else
@@ -68,14 +115,19 @@ void RLEdecode(unsigned char *p, unsigned int size, wxInputStream& s)
             cont = data & 0x3F;
             data = (unsigned char)s.GetC();
             for (i = 1; i <= cont; i++)
-                *(p++) = data;
+                *(p++) = (unsigned char)data;
             size -= cont;
         }
     }
 }
 
 
-/* PCX header */
+//-----------------------------------------------------------------------------
+// PCX reading and saving
+//-----------------------------------------------------------------------------
+
+// PCX header
+#define HDR_MANUFACTURER    0
 #define HDR_VERSION         1
 #define HDR_ENCODING        2
 #define HDR_BITSPERPIXEL    3
@@ -85,6 +137,7 @@ void RLEdecode(unsigned char *p, unsigned int size, wxInputStream& s)
 #define HDR_YMAX            10
 #define HDR_NPLANES         65
 #define HDR_BYTESPERLINE    66
+#define HDR_PALETTEINFO     68
 
 // image formats
 enum {
@@ -100,6 +153,7 @@ enum {
     wxPCX_VERERR = 3        // error in pcx version number
 };
 
+
 // ReadPCX:
 //  Loads a PCX file into the wxImage object pointed by image.
 //  Returns wxPCX_OK on success, or an error code otherwise
@@ -117,18 +171,17 @@ int ReadPCX(wxImage *image, wxInputStream& stream)
     int nplanes;                    // number of planes
     int encoding;                   // is the image RLE encoded?
     int format;                     // image format (8 bit, 24 bit)
-    unsigned int i;
-    off_t pos;
+    unsigned int i, j;
 
     // Read PCX header and check the version number (it must
     // be at least 5 or higher for 8 bit and 24 bit images).
-    //
+
     stream.Read(hdr, 128);
 
     if (hdr[HDR_VERSION] < 5) return wxPCX_VERERR;
 
     // Extract all image info from the PCX header.
-    //
+
     encoding     = hdr[HDR_ENCODING];
     nplanes      = hdr[HDR_NPLANES];
     bitsperpixel = hdr[HDR_BITSPERPIXEL];
@@ -140,7 +193,7 @@ int ReadPCX(wxImage *image, wxInputStream& stream)
 
     // Check image format. Currently supported formats are
     // 8 bits (8 bpp, 1 plane) and 24 bits (8 bpp, 3 planes).
-    //
+
     if ((nplanes == 3) && (bitsperpixel == 8))
         format = wxPCX_24BIT;
     else if ((nplanes == 1) && (bitsperpixel == 8))
@@ -148,24 +201,19 @@ int ReadPCX(wxImage *image, wxInputStream& stream)
     else
         return wxPCX_INVFORMAT;
 
-    // If the image is of type wxPCX_8BIT, then there is a
-    // palette at the end of the file. Read it now before
-    // proceeding.
-    //
-    if (format == wxPCX_8BIT)
-    {
-        pos = stream.TellI();
-        stream.SeekI(-769, wxFromEnd);
+    // If the image is of type wxPCX_8BIT, then there is
+    // a palette at the end of the image data. If we were
+    // working with a file, we could seek at the end to the
+    // end (SeekI(-769, wxFromEnd) and read the palette
+    // before proceeding. Unfortunately, this would prevent
+    // loading several PCXs in a single stream, so we can't
+    // do it. Thus, 8-bit images will have to be decoded in
+    // two passes: one to read and decode the image data,
+    // and another to replace 'colour indexes' with RGB
+    // values.
 
-        if (stream.GetC() != 12)
-            return wxPCX_INVFORMAT;
+    // Resize the image and allocate memory for a scanline.
 
-        stream.Read(pal, 768);
-        stream.SeekI(pos, wxFromStart);
-    }
-
-    // Allocate memory for a scanline and resize the image.
-    //
     image->Create(width, height);
 
     if (!image->Ok())
@@ -176,10 +224,10 @@ int ReadPCX(wxImage *image, wxInputStream& stream)
 
     // Now start reading the file, line by line, and store
     // the data in the format required by wxImage.
-    //
+
     dst = image->GetData();
 
-    for (; height; height--)
+    for (j = height; j; j--)
     {
         if (encoding)
             RLEdecode(p, bytesperline * nplanes, stream);
@@ -192,9 +240,9 @@ int ReadPCX(wxImage *image, wxInputStream& stream)
             {
                 for (i = 0; i < width; i++)
                 {
-                    *(dst++) = pal[ 3 * (p[i]) ];
-                    *(dst++) = pal[ 3 * (p[i]) + 1];
-                    *(dst++) = pal[ 3 * (p[i]) + 2];
+                    // first pass, just store the colour index
+                    *dst = p[i];
+                    dst += 3;
                 }
                 break;
             }
@@ -213,18 +261,179 @@ int ReadPCX(wxImage *image, wxInputStream& stream)
 
     free(p);
 
+    // For 8 bit images, we read the palette, and then do a second
+    // pass replacing indexes with their RGB values;
+
+    if (format == wxPCX_8BIT)
+    {
+        unsigned char index;
+
+        if (stream.GetC() != 12)
+            return wxPCX_INVFORMAT;
+
+        stream.Read(pal, 768);
+
+        p = image->GetData();
+        for (unsigned long k = height * width; k; k--)
+        {
+            index = *p;
+            *(p++) = pal[3 * index];
+            *(p++) = pal[3 * index + 1];
+            *(p++) = pal[3 * index + 2];
+        }
+
+#if wxUSE_PALETTE
+        unsigned char r[256];
+        unsigned char g[256];
+        unsigned char b[256];
+        for (i = 0; i < 256; i++)
+        {
+            r[i] = pal[3*i + 0];
+            g[i] = pal[3*i + 1];
+            b[i] = pal[3*i + 2];
+        }
+        image->SetPalette(wxPalette(256, r, g, b));
+#endif // wxUSE_PALETTE
+    }
+
     return wxPCX_OK;
 }
 
+// SavePCX:
+//  Saves a PCX file into the wxImage object pointed by image.
+//  Returns wxPCX_OK on success, or an error code otherwise
+//  (see above for error codes). Will try to save as 8-bit
+//  PCX if possible, and then fall back to 24-bit if there
+//  are more than 256 different colours.
+//
+int SavePCX(wxImage *image, wxOutputStream& stream)
+{
+    unsigned char hdr[128];         // PCX header
+    unsigned char pal[768];         // palette for 8 bit images
+    unsigned char *p;               // space to store one scanline
+    unsigned char *src;             // pointer into wxImage data
+    unsigned int width, height;     // size of the image
+    unsigned int bytesperline;      // bytes per line (each plane)
+    unsigned char nplanes = 3;      // number of planes
+    int format = wxPCX_24BIT;       // image format (8 bit, 24 bit)
+    wxImageHistogram histogram;     // image histogram
+    unsigned long key;              // key in the hashtable
+    unsigned int i;
+
+    // See if we can save as 8 bit.
+
+    if (image->CountColours(256) <= 256)
+    {
+        image->ComputeHistogram(histogram);
+        format = wxPCX_8BIT;
+        nplanes = 1;
+    }
+
+    // Get image dimensions, calculate bytesperline (must be even,
+    // according to PCX specs) and allocate space for one complete
+    // scanline.
+
+    if (!image->Ok())
+        return wxPCX_INVFORMAT;
+
+    width = image->GetWidth();
+    height = image->GetHeight();
+    bytesperline = width;
+    if (bytesperline % 2)
+        bytesperline++;
+
+    if ((p = (unsigned char *) malloc(bytesperline * nplanes)) == NULL)
+        return wxPCX_MEMERR;
+
+    // Build header data and write it to the stream. Initially,
+    // set all bytes to zero (most values default to zero).
+
+    memset(hdr, 0, sizeof(hdr));
+
+    hdr[HDR_MANUFACTURER]     = 10;
+    hdr[HDR_VERSION]          = 5;
+    hdr[HDR_ENCODING]         = 1;
+    hdr[HDR_NPLANES]          = nplanes;
+    hdr[HDR_BITSPERPIXEL]     = 8;
+    hdr[HDR_BYTESPERLINE]     = (unsigned char)(bytesperline % 256);
+    hdr[HDR_BYTESPERLINE + 1] = (unsigned char)(bytesperline / 256);
+    hdr[HDR_XMAX]             = (unsigned char)((width - 1)  % 256);
+    hdr[HDR_XMAX + 1]         = (unsigned char)((width - 1)  / 256);
+    hdr[HDR_YMAX]             = (unsigned char)((height - 1) % 256);
+    hdr[HDR_YMAX + 1]         = (unsigned char)((height - 1) / 256);
+    hdr[HDR_PALETTEINFO]      = 1;
+
+    stream.Write(hdr, 128);
+
+    // Encode image data line by line and write it to the stream
+
+    src = image->GetData();
+
+    for (; height; height--)
+    {
+        switch (format)
+        {
+            case wxPCX_8BIT:
+            {
+                unsigned char r, g, b;
+
+                for (i = 0; i < width; i++)
+                {
+                    r = *(src++);
+                    g = *(src++);
+                    b = *(src++);
+                    key = (r << 16) | (g << 8) | b;
+
+                    p[i] = (unsigned char)histogram[key].index;
+                }
+                break;
+            }
+            case wxPCX_24BIT:
+            {
+                for (i = 0; i < width; i++)
+                {
+                    p[i] = *(src++);
+                    p[i + bytesperline] = *(src++);
+                    p[i + 2 * bytesperline] = *(src++);
+                }
+                break;
+            }
+        }
+
+        RLEencode(p, bytesperline * nplanes, stream);
+    }
+
+    free(p);
+
+    // For 8 bit images, build the palette and write it to the stream:
+    if (format == wxPCX_8BIT)
+    {
+        // zero unused colours
+        memset(pal, 0, sizeof(pal));
+
+        unsigned long index;
+
+        for (wxImageHistogram::iterator entry = histogram.begin();
+             entry != histogram.end(); ++entry )
+        {
+            key = entry->first;
+            index = entry->second.index;
+            pal[3 * index]     = (unsigned char)(key >> 16);
+            pal[3 * index + 1] = (unsigned char)(key >> 8);
+            pal[3 * index + 2] = (unsigned char)(key);
+        }
+
+        stream.PutC(12);
+        stream.Write(pal, 768);
+    }
+
+    return wxPCX_OK;
+}
 
 //-----------------------------------------------------------------------------
 // wxPCXHandler
 //-----------------------------------------------------------------------------
 
-#if !USE_SHARED_LIBRARIES
-IMPLEMENT_DYNAMIC_CLASS(wxPCXHandler,wxImageHandler)
-#endif
-
 bool wxPCXHandler::LoadFile( wxImage *image, wxInputStream& stream, bool verbose, int WXUNUSED(index) )
 {
     int error;
@@ -234,7 +443,7 @@ bool wxPCXHandler::LoadFile( wxImage *image, wxInputStream& stream, bool verbose
         if (verbose)
             wxLogError(_("PCX: this is not a PCX file."));
 
-        return FALSE;
+        return false;
     }
 
     image->Destroy();
@@ -245,36 +454,50 @@ bool wxPCXHandler::LoadFile( wxImage *image, wxInputStream& stream, bool verbose
         {
             switch (error)
             {
-                case wxPCX_INVFORMAT: wxLogError(_("wxPCXHandler: image format unsupported")); break;
-                case wxPCX_MEMERR:    wxLogError(_("wxPCXHandler: couldn't allocate memory")); break;
-                case wxPCX_VERERR:    wxLogError(_("wxPCXHandler: version number too low")); break;
-                default:              wxLogError(_("wxPCXHandler: unknown error !!!"));
+                case wxPCX_INVFORMAT: wxLogError(_("PCX: image format unsupported")); break;
+                case wxPCX_MEMERR:    wxLogError(_("PCX: couldn't allocate memory")); break;
+                case wxPCX_VERERR:    wxLogError(_("PCX: version number too low")); break;
+                default:              wxLogError(_("PCX: unknown error !!!"));
             }
         }
         image->Destroy();
-        return FALSE;
+        return false;
     }
 
-    return TRUE;
+    return true;
 }
 
-bool wxPCXHandler::SaveFile( wxImage *WXUNUSED(image), wxOutputStream& WXUNUSED(stream), bool verbose )
+bool wxPCXHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbose )
 {
-    wxFAIL_MSG(wxT("wxPCXHandler::SaveFile still not implemented"));
+    int error;
 
-    return FALSE;
+    if ((error = SavePCX(image, stream)) != wxPCX_OK)
+    {
+        if (verbose)
+        {
+            switch (error)
+            {
+                case wxPCX_INVFORMAT: wxLogError(_("PCX: invalid image")); break;
+                case wxPCX_MEMERR:    wxLogError(_("PCX: couldn't allocate memory")); break;
+                default:              wxLogError(_("PCX: unknown error !!!"));
+            }
+        }
+    }
+
+    return (error == wxPCX_OK);
 }
 
 bool wxPCXHandler::DoCanRead( wxInputStream& stream )
 {
-    unsigned char c;
-
-    c = stream.GetC();
-    stream.SeekI(-1, wxFromCurrent);
+    unsigned char c = stream.GetC();
+    if ( !stream )
+        return false;
 
     // not very safe, but this is all we can get from PCX header :-(
-    return (c == 10);
+    return c == 10;
 }
 
-#endif // wxUSE_STREAMS && wxUSE_PCX
+#endif // wxUSE_STREAMS
+
+#endif // wxUSE_IMAGE && wxUSE_PCX