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simgear/simgear/screen/screen-dump.cxx
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97 lines
2.7 KiB
C++

// screen-dump.cxx -- dump a copy of the opengl screen buffer to a file
//
// Contributed by Richard Kaszeta <bofh@me.umn.edu>, started October 1999.
//
// 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.
//
// $Id$
#ifdef HAVE_CONFIG_H
# include <simgear_config.h>
#endif
#if defined(__CYGWIN__) /* && !defined(USING_X) */
#define WIN32
#endif
#if defined(WIN32) /* MINGW and MSC predefine WIN32 */
# include <windows.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <limits.h>
#include <GL/gl.h>
#include "screen-dump.hxx"
#define RGB3 3 // 3 bytes of color info per pixel
#define RGBA 4 // 4 bytes of color+alpha info
bool sg_glWritePPMFile(const char *filename, GLubyte *buffer, int win_width, int win_height, int mode)
{
int i, j, k, q;
unsigned char *ibuffer;
FILE *fp;
int pixelSize = mode==GL_RGBA?4:3;
ibuffer = (unsigned char *) malloc(win_width*win_height*RGB3);
if ( (fp = fopen(filename, "wb")) == NULL ) {
printf("Warning: cannot open %s\n", filename);
return false;
}
fprintf(fp, "P6\n# CREATOR: glReadPixel()\n%d %d\n%d\n",
win_width, win_height, UCHAR_MAX);
q = 0;
for (i = 0; i < win_height; i++)
for (j = 0; j < win_width; j++)
for (k = 0; k < RGB3; k++)
ibuffer[q++] = (unsigned char)
*(buffer + (pixelSize*((win_height-1-i)*win_width+j)+k));
fwrite(ibuffer, sizeof(unsigned char), RGB3*win_width*win_height, fp);
fclose(fp);
free(ibuffer);
printf("wrote file (%d x %d pixels, %d bytes)\n",
win_width, win_height, RGB3*win_width*win_height);
return true;
}
// dump the screen buffer to a ppm file
bool sg_glDumpWindow(const char *filename, int win_width, int win_height) {
GLubyte *buffer;
bool result;
buffer = (GLubyte *) malloc(win_width*win_height*RGBA);
// read window contents from color buffer with glReadPixels
glFinish();
glReadPixels(0, 0, win_width, win_height,
GL_RGBA, GL_UNSIGNED_BYTE, buffer);
result = sg_glWritePPMFile( filename, buffer, win_width, win_height,
GL_RGBA );
free(buffer);
return result;
}