fltk/fluid/gif.cxx

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//
Buttons with box(FL_NO_BOX) did not draw. Apparently they did in older versions of fltk, I restored this. (bug 108771) Removed 8-bit colormap drawing code that was not doing anything in fl_draw_image due to Mike's changes. I also made fl_color(r,g,b) actually allocate the requested color rather than the nearest fltk color-cube color (this is only done for the first color that maps to a given entry in the fltk color cube), the result is that pixmaps with a small number of colors are drawn much more accurately. The resulting code seems to produce better images and is a good deal smaller! Fixed makeinclude.in so CFLAGS are used for c source code instead of CXXFLAGS. (bug 108694) Better fix for gif files suggested by pauly (bug 108770) Performance of Fl_Gl_Window may be improved on some types of OpenGL implementations, in particular MESA or other software emulators, by setting the GL_SWAP_TYPE environment variable. This variable declares what is in the back buffer after you do a swapbuffers. setenv GL_SWAP_TYPE COPY This indicates that the back buffer is copied to the front buffer, and still contains it's old data. This is true of many hardware implementations. Setting this will speed up emulation of overlays, and widgets that can do partial update can take advantage of this as damage() will not be cleared to -1. setenv GL_SWAP_TYPE NODAMAGE This indicates that nothing changes the back buffer except drawing into it. This is true of MESA and Win32 software emulation and perhaps some hardware emulation on systems with lots of memory. All other values for GL_SWAP_TYPE, and not setting the variable, cause fltk to assumme that the back buffer must be completely redrawn after a swap. This is easily tested by running the gl_overlay demo program and seeing if the display is correct when you drag another window over it or if you drag the window off the screen and back on. You have to exit and run the program again for it to see any changes to the environment variable. git-svn-id: file:///fltk/svn/fltk/branches/branch-1.0@1246 ea41ed52-d2ee-0310-a9c1-e6b18d33e121
2000-07-07 12:38:58 +04:00
// "$Id: gif.cxx,v 1.3.2.3 2000/07/07 08:38:58 spitzak Exp $"
//
// GIF support for the Fast Light Tool Kit (FLTK).
//
// Copyright 1998-2000 by Bill Spitzak and others.
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Library General Public
// License as published by the Free Software Foundation; either
// version 2 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Library General Public License for more details.
//
// You should have received a copy of the GNU Library General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
// USA.
//
// Please report all bugs and problems to "fltk-bugs@fltk.org".
//
// Read a .gif file and convert it to a "xpm" format (actually my
// modified one with compressed colormaps).
// Extensively modified from original code for gif2ras by
// Patrick J. Naughton of Sun Microsystems. The original
// copyright notice follows:
/* gif2ras.c - Converts from a Compuserve GIF (tm) image to a Sun Raster image.
*
* Copyright (c) 1988 by Patrick J. Naughton
*
* Author: Patrick J. Naughton
* naughton@wind.sun.com
*
* Permission to use, copy, modify, and distribute this software and its
* documentation for any purpose and without fee is hereby granted,
* provided that the above copyright notice appear in all copies and that
* both that copyright notice and this permission notice appear in
* supporting documentation.
*
* This file is provided AS IS with no warranties of any kind. The author
* shall have no liability with respect to the infringement of copyrights,
* trade secrets or any patents by this file or any part thereof. In no
* event will the author be liable for any lost revenue or profits or
* other special, indirect and consequential damages.
*
* Comments and additions should be sent to the author:
*
* Patrick J. Naughton
* Sun Microsystems, Inc.
* 2550 Garcia Ave, MS 14-40
* Mountain View, CA 94043
* (415) 336-1080
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
typedef unsigned char uchar;
#define NEXTBYTE getc(GifFile)
#define GETSHORT(var) var = NEXTBYTE; var += NEXTBYTE << 8
int gif2xpm(
const char *infname,// filename for error messages
FILE *GifFile, // file to read
char*** datap, // return xpm data here
int** lengthp, // return line lengths here
int inumber // which image in movie (0 = first)
) {
{char b[6];
if (fread(b,1,6,GifFile)<6) return 0; /* quit on eof */
if (b[0]!='G' || b[1]!='I' || b[2] != 'F') {
fprintf(stderr,"%s is not a GIF file.\n", infname); return 0;}
if (b[3]!='8' || b[4]>'9' || b[5]!= 'a')
fprintf(stderr,"%s is version %c%c%c.\n",infname,b[3],b[4],b[5]);
}
int Width; GETSHORT(Width);
int Height; GETSHORT(Height);
uchar ch = NEXTBYTE;
char HasColormap = ((ch & 0x80) != 0);
int BitsPerPixel = (ch & 7) + 1;
int ColorMapSize = 1 << BitsPerPixel;
// int OriginalResolution = ((ch>>4)&7)+1;
// int SortedTable = (ch&8)!=0;
NEXTBYTE; // Background Color index
NEXTBYTE; // Aspect ratio is N/64
// Read in global colormap:
uchar transparent_pixel = 0;
char has_transparent = 0;
uchar Red[256], Green[256], Blue[256]; /* color map */
if (HasColormap) {
for (int i=0; i < ColorMapSize; i++) {
Red[i] = NEXTBYTE;
Green[i] = NEXTBYTE;
Blue[i] = NEXTBYTE;
}
} else {
fprintf(stderr,"%s does not have a colormap.\n", infname);
for (int i = 0; i < ColorMapSize; i++)
Red[i] = Green[i] = Blue[i] = (i*256+ColorMapSize-1)/ColorMapSize;
}
int CodeSize; /* Code size, init from GIF header, increases... */
char Interlace;
for (;;) {
int i = NEXTBYTE;
if (i<0) {fprintf(stderr,"%s: unexpected EOF\n",infname); return 0;}
int blocklen;
// if (i == 0x3B) return 0; eof code
if (i == 0x21) { // a "gif extension"
ch = NEXTBYTE;
blocklen = NEXTBYTE;
if (ch==0xF9 && blocklen==4) { // Netscape animation extension
char bits;
bits = NEXTBYTE;
NEXTBYTE; NEXTBYTE; // GETSHORT(delay);
transparent_pixel = NEXTBYTE;
if (bits & 1) has_transparent = 1;
blocklen = NEXTBYTE;
} else if (ch == 0xFF) { // Netscape repeat count
;
} else if (ch == 0xFE) { //Gif Comment
#if 0
if(blocklen>0) {
char *comment=new char[blocklen+1];
int l;
for(l=0;blocklen;l++,blocklen--)
comment[l]=NEXTBYTE;
comment[l]=0;
fprintf(stderr,"%s: Gif Comment: '%s'\n", infname, comment);
delete comment;
NEXTBYTE; //End marker
}
#endif
} else {
fprintf(stderr,"%s: unknown gif extension 0x%02x\n", infname, ch);
}
} else if (i == 0x2c) { // an image
NEXTBYTE; NEXTBYTE; // GETSHORT(x_position);
NEXTBYTE; NEXTBYTE; // GETSHORT(y_position);
GETSHORT(Width);
GETSHORT(Height);
ch = NEXTBYTE;
Interlace = ((ch & 0x40) != 0);
if (ch&0x80) {
// read local color map
int n = 1<<((ch&7)+1); // does this replace ColorMapSize ??
for (i=0; i < n; i++) {
Red[i] = NEXTBYTE;
Green[i] = NEXTBYTE;
Blue[i] = NEXTBYTE;
}
}
CodeSize = NEXTBYTE+1;
if (!inumber--) break; // okay, this is the image we want
blocklen = NEXTBYTE;
} else {
fprintf(stderr,"%s: unknown gif code 0x%02x\n", infname, i);
blocklen = 0;
}
// skip the data:
while (blocklen>0) {while (blocklen--) {NEXTBYTE;} blocklen=NEXTBYTE;}
}
uchar *Image = new uchar[Width*Height];
if (!Image) {
fprintf (stderr, "Insufficient memory\n");
exit (2);
}
int YC = 0, Pass = 0; /* Used to de-interlace the picture */
uchar *p = Image;
uchar *eol = p+Width;
int InitCodeSize = CodeSize;
int ClearCode = (1 << (CodeSize-1));
int EOFCode = ClearCode + 1;
int FirstFree = ClearCode + 2;
int FinChar = 0;
int ReadMask = (1<<CodeSize) - 1;
int FreeCode = FirstFree;
int OldCode = ClearCode;
// tables used by LZW decompresser:
short int Prefix[4096];
uchar Suffix[4096];
int blocklen = NEXTBYTE;
uchar thisbyte = NEXTBYTE; blocklen--;
int frombit = 0;
for (;;) {
/* Fetch the next code from the raster data stream. The codes can be
* any length from 3 to 12 bits, packed into 8-bit bytes, so we have to
* maintain our location as a pointer and a bit offset.
* In addition, gif adds totally useless and annoying block counts
* that must be correctly skipped over. */
int CurCode = thisbyte;
if (frombit+CodeSize > 7) {
if (blocklen <= 0) {
blocklen = NEXTBYTE;
if (blocklen <= 0) break;
}
thisbyte = NEXTBYTE; blocklen--;
CurCode |= thisbyte<<8;
}
if (frombit+CodeSize > 15) {
if (blocklen <= 0) {
blocklen = NEXTBYTE;
if (blocklen <= 0) break;
}
thisbyte = NEXTBYTE; blocklen--;
CurCode |= thisbyte<<16;
}
CurCode = (CurCode>>frombit)&ReadMask;
frombit = (frombit+CodeSize)%8;
if (CurCode == ClearCode) {
CodeSize = InitCodeSize;
ReadMask = (1<<CodeSize) - 1;
FreeCode = FirstFree;
OldCode = ClearCode;
continue;
}
if (CurCode == EOFCode) break;
uchar OutCode[1025]; // temporary array for reversing codes
uchar *tp = OutCode;
int i;
if (CurCode < FreeCode) i = CurCode;
else if (CurCode == FreeCode) {*tp++ = FinChar; i = OldCode;}
else {fprintf(stderr,"%s : LZW Barf!\n",infname); break;}
while (i >= ColorMapSize) {*tp++ = Suffix[i]; i = Prefix[i];}
*tp++ = FinChar = i;
while (tp > OutCode) {
*p++ = *--tp;
if (p >= eol) {
if (!Interlace) YC++;
else switch (Pass) {
case 0: YC += 8; if (YC >= Height) {Pass++; YC = 4;} break;
case 1: YC += 8; if (YC >= Height) {Pass++; YC = 2;} break;
case 2: YC += 4; if (YC >= Height) {Pass++; YC = 1;} break;
case 3: YC += 2; break;
}
if (YC>=Height) YC=0; /* cheap bug fix when excess data */
p = Image + YC*Width;
eol = p+Width;
}
}
if (OldCode != ClearCode) {
Prefix[FreeCode] = OldCode;
Suffix[FreeCode] = FinChar;
FreeCode++;
if (FreeCode > ReadMask) {
if (CodeSize < 12) {
CodeSize++;
ReadMask = (1 << CodeSize) - 1;
}
else FreeCode--;
}
}
OldCode = CurCode;
}
// We are done reading the file, now convert to xpm:
// allocate line pointer arrays:
char** data = new char*[Height+3];
*datap = data;
int* length = new int[Height+2];
*lengthp = length;
// transparent pixel must be zero, swap if it isn't:
if (has_transparent && transparent_pixel != 0) {
// swap transparent pixel with zero
p = Image+Width*Height;
while (p-- > Image) {
if (*p==transparent_pixel) *p = 0;
else if (!*p) *p = transparent_pixel;
}
uchar t;
t = Red[0]; Red[0] = Red[transparent_pixel]; Red[transparent_pixel] = t;
t =Green[0];Green[0]=Green[transparent_pixel];Green[transparent_pixel]=t;
t =Blue[0];Blue[0] =Blue[transparent_pixel];Blue[transparent_pixel] = t;
}
// find out what colors are actually used:
uchar used[256]; uchar remap[256];
int i;
for (i = 0; i < ColorMapSize; i++) used[i] = 0;
p = Image+Width*Height;
while (p-- > Image) used[*p] = 1;
// remap them to start with printing characters:
int base = has_transparent && used[0] ? ' ' : ' '+1;
int numcolors = 0;
for (i = 0; i < ColorMapSize; i++) if (used[i]) {
remap[i] = base++;
numcolors++;
}
// write the first line of xpm data (use suffix as temp array):
length[0] = sprintf((char*)(Suffix),
"%d %d %d %d",Width,Height,-numcolors,1);
data[0] = new char[length[0]+1];
strcpy(data[0], (char*)Suffix);
// write the colormap
length[1] = 4*numcolors;
data[1] = (char*)(p = new uchar[4*numcolors]);
for (i = 0; i < ColorMapSize; i++) if (used[i]) {
*p++ = remap[i];
*p++ = Red[i];
*p++ = Green[i];
*p++ = Blue[i];
}
// remap the image data:
p = Image+Width*Height;
while (p-- > Image) *p = remap[*p];
// split the image data into lines:
for (i=0; i<Height; i++) {
data[i+2] = (char*)(Image + i*Width);
length[i+2] = Width;
}
data[Height+2] = 0; // null to end string array
Buttons with box(FL_NO_BOX) did not draw. Apparently they did in older versions of fltk, I restored this. (bug 108771) Removed 8-bit colormap drawing code that was not doing anything in fl_draw_image due to Mike's changes. I also made fl_color(r,g,b) actually allocate the requested color rather than the nearest fltk color-cube color (this is only done for the first color that maps to a given entry in the fltk color cube), the result is that pixmaps with a small number of colors are drawn much more accurately. The resulting code seems to produce better images and is a good deal smaller! Fixed makeinclude.in so CFLAGS are used for c source code instead of CXXFLAGS. (bug 108694) Better fix for gif files suggested by pauly (bug 108770) Performance of Fl_Gl_Window may be improved on some types of OpenGL implementations, in particular MESA or other software emulators, by setting the GL_SWAP_TYPE environment variable. This variable declares what is in the back buffer after you do a swapbuffers. setenv GL_SWAP_TYPE COPY This indicates that the back buffer is copied to the front buffer, and still contains it's old data. This is true of many hardware implementations. Setting this will speed up emulation of overlays, and widgets that can do partial update can take advantage of this as damage() will not be cleared to -1. setenv GL_SWAP_TYPE NODAMAGE This indicates that nothing changes the back buffer except drawing into it. This is true of MESA and Win32 software emulation and perhaps some hardware emulation on systems with lots of memory. All other values for GL_SWAP_TYPE, and not setting the variable, cause fltk to assumme that the back buffer must be completely redrawn after a swap. This is easily tested by running the gl_overlay demo program and seeing if the display is correct when you drag another window over it or if you drag the window off the screen and back on. You have to exit and run the program again for it to see any changes to the environment variable. git-svn-id: file:///fltk/svn/fltk/branches/branch-1.0@1246 ea41ed52-d2ee-0310-a9c1-e6b18d33e121
2000-07-07 12:38:58 +04:00
return Height+1;
}
//
Buttons with box(FL_NO_BOX) did not draw. Apparently they did in older versions of fltk, I restored this. (bug 108771) Removed 8-bit colormap drawing code that was not doing anything in fl_draw_image due to Mike's changes. I also made fl_color(r,g,b) actually allocate the requested color rather than the nearest fltk color-cube color (this is only done for the first color that maps to a given entry in the fltk color cube), the result is that pixmaps with a small number of colors are drawn much more accurately. The resulting code seems to produce better images and is a good deal smaller! Fixed makeinclude.in so CFLAGS are used for c source code instead of CXXFLAGS. (bug 108694) Better fix for gif files suggested by pauly (bug 108770) Performance of Fl_Gl_Window may be improved on some types of OpenGL implementations, in particular MESA or other software emulators, by setting the GL_SWAP_TYPE environment variable. This variable declares what is in the back buffer after you do a swapbuffers. setenv GL_SWAP_TYPE COPY This indicates that the back buffer is copied to the front buffer, and still contains it's old data. This is true of many hardware implementations. Setting this will speed up emulation of overlays, and widgets that can do partial update can take advantage of this as damage() will not be cleared to -1. setenv GL_SWAP_TYPE NODAMAGE This indicates that nothing changes the back buffer except drawing into it. This is true of MESA and Win32 software emulation and perhaps some hardware emulation on systems with lots of memory. All other values for GL_SWAP_TYPE, and not setting the variable, cause fltk to assumme that the back buffer must be completely redrawn after a swap. This is easily tested by running the gl_overlay demo program and seeing if the display is correct when you drag another window over it or if you drag the window off the screen and back on. You have to exit and run the program again for it to see any changes to the environment variable. git-svn-id: file:///fltk/svn/fltk/branches/branch-1.0@1246 ea41ed52-d2ee-0310-a9c1-e6b18d33e121
2000-07-07 12:38:58 +04:00
// End of "$Id: gif.cxx,v 1.3.2.3 2000/07/07 08:38:58 spitzak Exp $".
//