/**

  * $Id$

  *

  * The PC side of the video support (responsible for actually displaying / 

  * rendering frames)

  *

  * Copyright (c) 2005 Nathan Keynes.

  *

  * This program is free software; you can redistribute it and/or modify

  * it under the terms of the GNU General Public License as published by

  * the Free Software Foundation; either version 2 of the License, or

  * (at your option) any later version.

  *

  * This program 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 General Public License for more details.

  */

 #include <assert.h>

 #include <stdlib.h>

 #include <gdk/gdk.h>

 #include <gdk-pixbuf/gdk-pixbuf.h>

 #include <gtk/gtkwidget.h>

 #include <GL/glu.h>

 #include <GL/osmesa.h>

 #include "lxdream.h"

 #include "display.h"

 #define MAX_PIXBUF 16

 extern GtkWidget *gtk_video_drawable;

 extern int video_width, video_height;

 static render_buffer_t gdk_pixbuf_create_render_buffer( uint32_t width, uint32_t height );

 static void gdk_pixbuf_destroy_render_buffer( render_buffer_t buffer );

 static gboolean gdk_pixbuf_set_render_target( render_buffer_t buffer );

 static void gdk_pixbuf_display_render_buffer( render_buffer_t buffer );

 static void gdk_pixbuf_load_frame_buffer( frame_buffer_t frame, render_buffer_t buffer );

 static void gdk_pixbuf_display_blank( uint32_t colour );

 static gboolean gdk_pixbuf_read_render_buffer( unsigned char *target, render_buffer_t buffer, int rowstride, int format );

 static void *pixbuf_array[MAX_PIXBUF];

 unsigned int pixbuf_max = 0;

 OSMesaContext osmesa_context = NULL;

 void video_gdk_init_driver( display_driver_t driver )

 {

     pixbuf_max = 0;

     driver->create_render_buffer = gdk_pixbuf_create_render_buffer;

     driver->destroy_render_buffer = gdk_pixbuf_destroy_render_buffer;

     driver->set_render_target = gdk_pixbuf_set_render_target;

     driver->display_render_buffer = gdk_pixbuf_display_render_buffer;

     driver->load_frame_buffer = gdk_pixbuf_load_frame_buffer;

     driver->display_blank = gdk_pixbuf_display_blank;

     driver->read_render_buffer = gdk_pixbuf_read_render_buffer;

     osmesa_context = OSMesaCreateContextExt( OSMESA_RGBA, 32, 0, 0, 0 );

     OSMesaMakeCurrent( osmesa_context, NULL, GL_UNSIGNED_BYTE, 640, 480 );

     pvr2_setup_gl_context();

 }

 int video_gdk_find_free()

 {

     unsigned int i;

     for( i=0; i<pixbuf_max; i++ ) {

         if( pixbuf_array[i] == NULL ) {

             return i;

         }

     }

     if( i < MAX_PIXBUF ) {

         return pixbuf_max++;

     }

     return -1;

 }

 void video_gdk_shutdown()

 {

     unsigned int i;

     for( i=0; i<pixbuf_max; i++ ) {

         if( pixbuf_array[i] != NULL ) {

             g_free(pixbuf_array[i]);

             pixbuf_array[i] = NULL;

         }

     }

     pixbuf_max = 0;

     OSMesaDestroyContext( osmesa_context );

 }

 static render_buffer_t gdk_pixbuf_create_render_buffer( uint32_t width, uint32_t height )

 {

     render_buffer_t buf = g_malloc0(sizeof(struct render_buffer));

     gboolean alpha = FALSE;

     buf->width = width;

     buf->height = height;

     buf->buf_id = video_gdk_find_free();

     pixbuf_array[buf->buf_id] = g_malloc0( width * height * 4 );

     return buf;

 }

 static void gdk_pixbuf_destroy_render_buffer( render_buffer_t buffer )

 {

     g_free(pixbuf_array[buffer->buf_id] );

     pixbuf_array[buffer->buf_id] = NULL;

     if( buffer->buf_id == (pixbuf_max-1) ) {

         pixbuf_max--;

     }

 }

 static void gdk_pixbuf_display_render_buffer( render_buffer_t buffer )

 {

     glFinish();

     void *pb = pixbuf_array[buffer->buf_id];

     GdkGC *gc = gtk_video_drawable->style->fg_gc[GTK_STATE_NORMAL];

     GdkColor black = {0,0,0,0};

     assert(gc);

     int x1=0,y1=0,x2=video_width,y2=video_height;

     int ah = video_width * 0.75;

     if( ah > video_height ) {

         int w = (video_height/0.75);

         x1 = (video_width - w)/2;

         x2 -= x1;

         gdk_gc_set_foreground( gc, &black );

         gdk_gc_set_background( gc, &black );

         gdk_draw_rectangle( gtk_video_drawable->window, gc, TRUE, 0, 0, x1, video_height );

         gdk_draw_rectangle( gtk_video_drawable->window, gc, TRUE, x2, 0, video_width, video_height );

     } else if( ah < video_height ) {

         y1 = (video_height - ah)/2;

         y2 -= y1;

         gdk_gc_set_foreground( gc, &black );

         gdk_gc_set_background( gc, &black );

         gdk_draw_rectangle( gtk_video_drawable->window, gc, TRUE, 0, 0, video_width, y1 );

         gdk_draw_rectangle( gtk_video_drawable->window, gc, TRUE, 0, y2, video_width, video_height );

     }

     int w = x2-x1;

     int h = y2-y1;

     if( w != buffer->width || h != buffer->height ) {

         gdk_draw_rgb_32_image( gtk_video_drawable->window, gc, x1, y1, buffer->width, buffer->height, GDK_RGB_DITHER_NONE,

                 pb, buffer->width*4 );

     } else {

         gdk_draw_rgb_32_image( gtk_video_drawable->window, gc, x1, y1, buffer->width, buffer->height, GDK_RGB_DITHER_NONE,

                 pb, buffer->width*4 );

     }

 }

 static void gdk_pixbuf_display_blank( uint32_t colour )

 {

     GdkGC *gc = gtk_video_drawable->style->fg_gc[GTK_STATE_NORMAL];

     GdkColor col = { };

     gdk_gc_set_foreground( gc, &col );

     gdk_gc_set_background( gc, &col );

     gdk_draw_rectangle( gtk_video_drawable->window, gc, TRUE, 0, 0, video_width, video_height );

 }

 static gboolean gdk_pixbuf_set_render_target( render_buffer_t buffer )

 {

     glFinish();

     void *pb = pixbuf_array[buffer->buf_id];

     OSMesaMakeCurrent( osmesa_context, pb, GL_UNSIGNED_BYTE,

                        buffer->width, buffer->height );

     //OSMesaPixelStore( OSMESA_Y_UP, 0 );

     glViewport( 0, 0, buffer->width, buffer->height );

     glDrawBuffer(GL_FRONT);

     return TRUE;

 }

 static void gdk_pixbuf_load_frame_buffer( frame_buffer_t frame, render_buffer_t buffer )

 {

     glFinish();

     void *pb = pixbuf_array[buffer->buf_id];

     OSMesaMakeCurrent( osmesa_context, pb, GL_UNSIGNED_BYTE,

                        buffer->width, buffer->height );

     GLenum type = colour_formats[frame->colour_format].type;

     GLenum format = colour_formats[frame->colour_format].format;

     int bpp = colour_formats[frame->colour_format].bpp;

     int rowstride = (frame->rowstride / bpp) - frame->width;

     gl_reset_state();

     glPixelStorei( GL_UNPACK_ROW_LENGTH, rowstride );

     glRasterPos2f(0.375, frame->height-0.375);

     glPixelZoom( 1.0, 1.0 );

     glDrawPixels( frame->width, frame->height, format, type, frame->data );

     glFlush();

 }

 static gboolean gdk_pixbuf_read_render_buffer( unsigned char *target, render_buffer_t buffer, int rowstride, int format )

 {

     glFinish();

     void *pb = pixbuf_array[buffer->buf_id];

     OSMesaMakeCurrent( osmesa_context, pb, GL_UNSIGNED_BYTE,

                        buffer->width, buffer->height );

     glReadBuffer( GL_FRONT );

     return gl_read_render_buffer( target, buffer, rowstride, format );

 }