1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/drivers/video_gl.c	Mon Jan 15 08:32:09 2007 +0000
     1.3 @@ -0,0 +1,72 @@
     1.4 +/**
     1.5 + * $Id: video_gl.c,v 1.1 2007-01-14 02:55:06 nkeynes Exp $
     1.6 + *
     1.7 + * Common GL code that doesn't depend on a specific implementation
     1.8 + *
     1.9 + * Copyright (c) 2005 Nathan Keynes.
    1.10 + *
    1.11 + * This program is free software; you can redistribute it and/or modify
    1.12 + * it under the terms of the GNU General Public License as published by
    1.13 + * the Free Software Foundation; either version 2 of the License, or
    1.14 + * (at your option) any later version.
    1.15 + *
    1.16 + * This program is distributed in the hope that it will be useful,
    1.17 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
    1.18 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    1.19 + * GNU General Public License for more details.
    1.20 + */
    1.21 +
    1.22 +#include "dream.h"
    1.23 +#include "drivers/video_gl.h"
    1.24 +#include <GL/gl.h>
    1.25 +
    1.26 +char *required_extensions[] = { "GL_EXT_framebuffer_object", NULL };
    1.27 +
    1.28 +/**
    1.29 + * Test if a specific extension is supported. From opengl.org
    1.30 + * @param extension extension name to check for
    1.31 + * @return TRUE if supported, otherwise FALSE.
    1.32 + */
    1.33 +gboolean isGLExtensionSupported( const char *extension )
    1.34 +{
    1.35 +    const GLubyte *extensions = NULL;
    1.36 +    const GLubyte *start;
    1.37 +    GLubyte *where, *terminator;
    1.38 +
    1.39 +    /* Extension names should not have spaces. */
    1.40 +    where = (GLubyte *) strchr(extension, ' ');
    1.41 +    if (where || *extension == '\0')
    1.42 +	return 0;
    1.43 +    extensions = glGetString(GL_EXTENSIONS);
    1.44 +    /* It takes a bit of care to be fool-proof about parsing the
    1.45 +       OpenGL extensions string. Don't be fooled by sub-strings,
    1.46 +       etc. */
    1.47 +    start = extensions;
    1.48 +    for (;;) {
    1.49 +	where = (GLubyte *) strstr((const char *) start, extension);
    1.50 +	if (!where)
    1.51 +	    break;
    1.52 +	terminator = where + strlen(extension);
    1.53 +	if (where == start || *(where - 1) == ' ')
    1.54 +	    if (*terminator == ' ' || *terminator == '\0')
    1.55 +		return TRUE;
    1.56 +	start = terminator;
    1.57 +    }
    1.58 +    return FALSE;
    1.59 +}
    1.60 +
    1.61 +gboolean hasRequiredGLExtensions( ) 
    1.62 +{
    1.63 +    int i;
    1.64 +    gboolean isOK = TRUE;
    1.65 +    fprintf( stdout, "GL Extensions: %s\n", glGetString(GL_EXTENSIONS) );
    1.66 +
    1.67 +
    1.68 +    for( i=0; required_extensions[i] != NULL; i++ ) {
    1.69 +	if( !isGLExtensionSupported(required_extensions[i]) ) {
    1.70 +	    ERROR( "Required OpenGL extension not supported: %s", required_extensions[i] );
    1.71 +	    isOK = FALSE;
    1.72 +	}
    1.73 +    }
    1.74 +    return isOK;
    1.75 +}