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lxdream.org :: lxdream/src/drivers/video_glx.c
lxdream 0.9.1
released Jun 29
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filename src/drivers/video_glx.c
changeset 1001:cbb01e3114ea
prev982:2d6b3f29f878
next1065:bc1cc0c54917
author nkeynes
date Wed Mar 25 11:57:05 2009 +0000 (12 years ago)
permissions -rw-r--r--
last change Change glXMakeContextCurrent call to glXMakeCurrent - works around crash bug
in mesa: http://www.mail-archive.com/mesa-commit@lists.freedesktop.org/msg04338.html
file annotate diff log raw
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/**
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 * $Id$
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 *
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 * Shared functions for all X11-based display drivers.
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 *
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 * Copyright (c) 2005 Nathan Keynes.
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 *
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 * This program is free software; you can redistribute it and/or modify
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 * it under the terms of the GNU General Public License as published by
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 * the Free Software Foundation; either version 2 of the License, or
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 * (at your option) any later version.
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 *
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 * This program is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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 * GNU General Public License for more details.
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 */
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#include <stdlib.h>
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#include <string.h>
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#include "display.h"
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#include <X11/Xlib.h>
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#include <GL/glx.h>
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#include "pvr2/pvr2.h"
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#include "pvr2/glutil.h"
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#include "drivers/video_glx.h"
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#include "drivers/video_gl.h"
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/**
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 * General X11 parameters. The front-end driver is expected to set this up
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 * by calling video_glx_init after initializing itself.
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 */
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Display *video_x11_display = NULL;
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Window video_x11_window = 0;
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static int glx_version = 100;
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static XVisualInfo *glx_visual = NULL;
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static GLXFBConfig glx_fbconfig;
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static GLXContext glx_context = NULL;
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static gboolean glx_is_initialized = FALSE;
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static gboolean glx_fbconfig_supported = FALSE;
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static gboolean glx_pbuffer_supported = FALSE;
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static GLuint glx_pbuffer_texture = 0; 
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/* Prototypes for pbuffer support methods */
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static void glx_pbuffer_init( display_driver_t driver );
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static render_buffer_t glx_pbuffer_create_render_buffer( uint32_t width, uint32_t height, GLuint tex_id );
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static void glx_pbuffer_destroy_render_buffer( render_buffer_t buffer );
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static gboolean glx_pbuffer_set_render_target( render_buffer_t buffer );
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static void glx_pbuffer_finish_render( render_buffer_t buffer );
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static void glx_pbuffer_display_render_buffer( render_buffer_t buffer );
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static void glx_pbuffer_load_frame_buffer( frame_buffer_t frame, render_buffer_t buffer );
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static void glx_pbuffer_display_blank( uint32_t colour );
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static gboolean glx_pbuffer_read_render_buffer( unsigned char *target, render_buffer_t buffer, int rowstride, int format );
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/**
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 * Test if a specific extension is supported. From opengl.org
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 * @param extension extension name to check for
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 * @return TRUE if supported, otherwise FALSE.
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 */
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gboolean isServerGLXExtensionSupported( Display *display, int screen, 
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                                        const char *extension )
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{
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    const char *extensions = NULL;
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    const char *start;
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    char *where, *terminator;
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    /* Extension names should not have spaces. */
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    where = strchr(extension, ' ');
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    if (where || *extension == '\0')
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        return 0;
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    extensions = glXQueryServerString(display, screen, GLX_EXTENSIONS);
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    start = extensions;
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    for (;;) {
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        where = strstr((const char *) start, extension);
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        if (!where)
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            break;
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        terminator = where + strlen(extension);
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        if (where == start || *(where - 1) == ' ')
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            if (*terminator == ' ' || *terminator == '\0')
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                return TRUE;
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        start = terminator;
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    }
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    return FALSE;
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}
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gboolean video_glx_init( Display *display, int screen )
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{
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    int major, minor;
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    int glx_major, glx_minor, glx_error;
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    if( glx_is_initialized ) {
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        return TRUE;
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    }
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    Bool result = XQueryExtension( display, "GLX", &glx_major, &glx_minor, &glx_error ) &&
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                  glXQueryVersion( display, &major, &minor );
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    if( result == False ) {
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        ERROR( "GLX not supported on display" );
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        return FALSE;
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    }
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    glx_version = (major*100) + minor;
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#ifdef APPLE_BUILD
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    /* fbconfig is broken on at least the 10.5 GLX implementation */
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    glx_fbconfig_supported = FALSE;
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#else
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    glx_fbconfig_supported = (glx_version >= 103 || 
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            isServerGLXExtensionSupported(display, screen,
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                    "GLX_SGIX_fbconfig") );
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#endif
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    glx_pbuffer_supported = (glx_version >= 103 ||
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            isServerGLXExtensionSupported(display, screen,
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                    "GLX_SGIX_pbuffer") );
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//    glx_fbconfig_supported = FALSE;
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    if( glx_fbconfig_supported ) {
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        int nelem;
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        int fb_attribs[] = { GLX_DRAWABLE_TYPE, 
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                GLX_PBUFFER_BIT|GLX_WINDOW_BIT, 
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                GLX_RENDER_TYPE, GLX_RGBA_BIT, 
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                GLX_DEPTH_SIZE, 24, 
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                GLX_STENCIL_SIZE, 8, 0 };
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        GLXFBConfig *configs = glXChooseFBConfig( display, screen, 
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                fb_attribs, &nelem );
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        if( configs == NULL || nelem == 0 ) {
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            /* Try a 16-bit depth buffer and see if it helps */
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            fb_attribs[5] = 16;
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            configs = glXChooseFBConfig( display, screen, fb_attribs, &nelem );
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            if( nelem > 0 ) {
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                WARN( "Using a 16-bit depth buffer - expect video glitches" );
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            }
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        }
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        if( configs == NULL || nelem == 0 ) {
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            /* Still didn't work. Fallback to 1.2 methods */
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            glx_fbconfig_supported = FALSE;
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            glx_pbuffer_supported = FALSE;
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        } else {
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            glx_fbconfig = configs[0];
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            glx_visual = glXGetVisualFromFBConfig(display, glx_fbconfig);
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            XFree(configs);
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        }
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    }
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    if( !glx_fbconfig_supported ) {
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        int attribs[] = { GLX_RGBA, GLX_DEPTH_SIZE, 24, GLX_STENCIL_SIZE, 8, 0 };
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        glx_visual = glXChooseVisual( display, screen, attribs );
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        if( glx_visual == NULL ) {
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            /* Try the 16-bit fallback here too */
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            attribs[2] = 16;
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            glx_visual = glXChooseVisual( display, screen, attribs );
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            if( glx_visual != NULL ) {
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                WARN( "Using a 16-bit depth buffer - expect video glitches" );
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            }
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        }
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    }
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    if( glx_visual == NULL ) {
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        return FALSE;
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    }
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    glx_is_initialized = TRUE;
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    return TRUE;
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}
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gboolean video_glx_init_context( Display *display, Window window )
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{
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    if( glx_fbconfig_supported ) {
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        glx_context = glXCreateNewContext( display, glx_fbconfig, 
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                GLX_RGBA_TYPE, NULL, True );
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        if( glx_context == NULL ) {
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            ERROR( "Unable to create a GLX Context.");
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            return FALSE;
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        }
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        if( glXMakeCurrent( display, window,
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                glx_context ) == False ) {
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            ERROR( "Unable to prepare GLX context for drawing" );
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            glXDestroyContext( display, glx_context );
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            return FALSE;
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        }
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    } else {
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        glx_context = glXCreateContext( display, glx_visual, None, True );
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        if( glx_context == NULL ) {
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            ERROR( "Unable to create a GLX Context.");
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            return FALSE;
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        }
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        if( glXMakeCurrent( display, window, glx_context ) == False ) {
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            ERROR( "Unable to prepare GLX context for drawing" );
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            glXDestroyContext( display, glx_context );
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            return FALSE;
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        }
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    }
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    if( !glXIsDirect(display, glx_context) ) {
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        WARN( "Not using direct rendering - this is likely to be slow" );
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    }
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    video_x11_display = display;
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    video_x11_window = window;
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    return TRUE;
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}
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gboolean video_glx_init_driver( display_driver_t driver )
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{
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    if( gl_fbo_is_supported() ) { // First preference
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        gl_fbo_init(driver);
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    } else if( glx_pbuffer_supported ) {
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        glx_pbuffer_init(driver);
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    } else {
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        ERROR( "Unable to create render buffers (requires either EXT_framebuffer_object or GLX 1.3+)" );
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        video_glx_shutdown();
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        return FALSE;
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    }
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    return TRUE;
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}
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void video_glx_shutdown()
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{
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    //    texcache_gl_shutdown();
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    glx_is_initialized = FALSE;
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    if( glx_context != NULL ) {
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        glXDestroyContext( video_x11_display, glx_context );
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        glx_context = NULL;
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    }
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    if( glx_visual != NULL ) {
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        XFree(glx_visual);
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        glx_visual = NULL;
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    }
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}
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XVisualInfo *video_glx_get_visual()
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{
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    return glx_visual;
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}
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int video_glx_load_font( const gchar *font_name )
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{
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    int lists;
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    XFontStruct *font = XLoadQueryFont(video_x11_display, font_name );
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    if (font == NULL)
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        return -1;
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    lists = glGenLists(96);
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    glXUseXFont(font->fid, 32, 96, lists);
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    XFreeFont(video_x11_display, font);
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    return lists;
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}
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void video_glx_swap_buffers( void )
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{
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    glXSwapBuffers( video_x11_display, video_x11_window );
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}
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void video_glx_make_window_current( void )
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{
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    glXMakeCurrent( video_x11_display, video_x11_window, glx_context );
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}
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// Pbuffer support
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/**
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 * Construct the initial frame buffers and allocate ids for everything.
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 * The render handling driver methods are set to the fbo versions.
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 */
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static void glx_pbuffer_init( display_driver_t driver ) 
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{
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    GLint stencil_bits = 0;
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    /* Retrieve the number of stencil bits */
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    glGetIntegerv( GL_STENCIL_BITS, &stencil_bits );
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    driver->capabilities.stencil_bits = stencil_bits;
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    glGenTextures( 1, &glx_pbuffer_texture );
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    driver->create_render_buffer = glx_pbuffer_create_render_buffer;
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    driver->destroy_render_buffer = glx_pbuffer_destroy_render_buffer;
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    driver->set_render_target = glx_pbuffer_set_render_target;
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    driver->finish_render = glx_pbuffer_finish_render;
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    driver->display_render_buffer = glx_pbuffer_display_render_buffer;
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    driver->load_frame_buffer = glx_pbuffer_load_frame_buffer;
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    driver->display_blank = glx_pbuffer_display_blank;
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    driver->read_render_buffer = glx_pbuffer_read_render_buffer;
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}
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void glx_pbuffer_shutdown()
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{
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    glDeleteTextures( 1, &glx_pbuffer_texture );
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}
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static render_buffer_t glx_pbuffer_create_render_buffer( uint32_t width, uint32_t height, GLuint tex_id )
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{
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    int attribs[] = { GLX_PBUFFER_WIDTH, width, GLX_PBUFFER_HEIGHT, height,
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            GLX_PRESERVED_CONTENTS, True, 0 };
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    GLXPbuffer pb = glXCreatePbuffer( video_x11_display, glx_fbconfig, attribs );
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    if( pb == (GLXPbuffer)NULL ) {
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        ERROR( "Unable to create pbuffer" );
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        return NULL;
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    }
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    render_buffer_t buffer = calloc( sizeof(struct render_buffer), 1 );
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    buffer->width = width;
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    buffer->height = height;
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    buffer->buf_id = pb;
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    buffer->tex_id = tex_id;
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    return buffer;
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}
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static void glx_pbuffer_destroy_render_buffer( render_buffer_t buffer )
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{
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    glXDestroyPbuffer( video_x11_display, (GLXPbuffer)buffer->buf_id );
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    buffer->buf_id = 0;
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    free( buffer );
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}
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static gboolean glx_pbuffer_set_render_target( render_buffer_t buffer )
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{
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    glFinish();
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    if( glXMakeContextCurrent( video_x11_display, (GLXPbuffer)buffer->buf_id, (GLXPbuffer)buffer->buf_id, glx_context ) == False ) {
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        ERROR( "Make context current (pbuffer) failed!" );
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    }
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    /* setup the gl context */
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    glViewport( 0, 0, buffer->width, buffer->height );
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    glDrawBuffer(GL_FRONT);
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   333
    return TRUE;
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   334
}
nkeynes@545
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static void glx_pbuffer_finish_render( render_buffer_t buffer )
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{
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    glFinish();
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    if( buffer->tex_id != 0 ) {
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        // The pbuffer should already be the current context, but just in case...
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        glXMakeContextCurrent( video_x11_display, (GLXPbuffer)buffer->buf_id, (GLXPbuffer)buffer->buf_id, glx_context );
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        glBindTexture( GL_TEXTURE_RECTANGLE_ARB, buffer->tex_id );
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        glCopyTexImage2D(GL_TEXTURE_RECTANGLE_ARB, 0, GL_RGBA, 0, 0, buffer->width, buffer->height, 0 );
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    }
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}
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   346
    
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/**
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 * Render the texture holding the given buffer to the front window
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 * buffer.
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 */
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static void glx_pbuffer_display_render_buffer( render_buffer_t buffer )
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{
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    glFinish();
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    glReadBuffer( GL_FRONT );
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    glDrawBuffer( GL_FRONT );
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    glXMakeContextCurrent( video_x11_display, (GLXPbuffer)buffer->buf_id, (GLXPbuffer)buffer->buf_id, glx_context );
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    glBindTexture( GL_TEXTURE_RECTANGLE_ARB, glx_pbuffer_texture );
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   359
    glCopyTexImage2D(GL_TEXTURE_RECTANGLE_ARB, 0, GL_RGBA, 0, 0, buffer->width, buffer->height, 0 );
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   360
    video_glx_make_window_current();
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   361
    gl_texture_window( buffer->width, buffer->height, glx_pbuffer_texture, buffer->inverted );
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   362
}
nkeynes@545
   363
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   364
static void glx_pbuffer_load_frame_buffer( frame_buffer_t frame, render_buffer_t buffer )
nkeynes@545
   365
{
nkeynes@545
   366
    glFinish();
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   367
    glXMakeContextCurrent( video_x11_display, (GLXPbuffer)buffer->buf_id, (GLXPbuffer)buffer->buf_id, glx_context );
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   368
    GLenum type = colour_formats[frame->colour_format].type;
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   369
    GLenum format = colour_formats[frame->colour_format].format;
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   370
    int bpp = colour_formats[frame->colour_format].bpp;
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   371
    int rowstride = (frame->rowstride / bpp) - frame->width;
nkeynes@736
   372
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   373
    gl_reset_state();
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   374
    glPixelStorei( GL_UNPACK_ROW_LENGTH, rowstride );
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   375
    glRasterPos2f(0.375, frame->height-0.375);
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   376
    glPixelZoom( 1.0, 1.0 );
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   377
    glDrawPixels( frame->width, frame->height, format, type, frame->data );
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   378
    glFlush();
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   379
}
nkeynes@545
   380
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   381
static void glx_pbuffer_display_blank( uint32_t colour )
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   382
{
nkeynes@545
   383
    glFinish();
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   384
    video_glx_make_window_current();
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   385
    gl_display_blank( colour );
nkeynes@545
   386
}
nkeynes@545
   387
nkeynes@545
   388
static gboolean glx_pbuffer_read_render_buffer( unsigned char *target, render_buffer_t buffer, 
nkeynes@736
   389
                                                int rowstride, int format )
nkeynes@545
   390
{
nkeynes@545
   391
    glXMakeCurrent( video_x11_display, (GLXDrawable)buffer->buf_id, glx_context );
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   392
    glReadBuffer( GL_FRONT );
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   393
    return gl_read_render_buffer( target, buffer, rowstride, format );
nkeynes@545
   394
}
nkeynes@545
   395
nkeynes@545
   396
.