source: trunk/third/gtkhtml3/src/htmldrawqueue.c @ 21116

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/* This file is part of the GtkHTML library.

   Copyright (C) 1999, 2000 Helix Code, Inc.
   
   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; see the file COPYING.LIB.  If not, write to
   the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.
*/

#include <config.h>
#include <gtk/gtksignal.h>
#include "htmlengine-edit-cursor.h"
#include "htmlcolor.h"
#include "htmldrawqueue.h"
#include "htmlengine.h"
#include "htmlgdkpainter.h"
#include "htmlimage.h"
#include "htmlpainter.h"
#include "htmlobject.h"
#include "htmltextslave.h"
#include "htmlsettings.h"
#include "gtkhtml.h"


/* HTMLDrawQueueClearElement handling.  */

static HTMLDrawQueueClearElement *
clear_element_new (gint            x,
                   gint            y,
                   guint           width,
                   guint           height,
                   const GdkColor *background_color)
{
        HTMLDrawQueueClearElement *new;

        new = g_new (HTMLDrawQueueClearElement, 1);

        new->x = x;
        new->y = y;
        new->width = width;
        new->height = height;

        /* GDK color API non const-correct.  */
        new->background_color = gdk_color_copy ((GdkColor *) background_color);

        new->background_image = NULL;
        new->background_image_x_offset = 0;
        new->background_image_y_offset = 0;

        return new;
}

static void
clear_element_destroy (HTMLDrawQueueClearElement *elem)
{
        g_return_if_fail (elem != NULL);

        if (elem->background_color != NULL)
                gdk_color_free (elem->background_color);

        if (elem->background_image != NULL)
                gdk_pixbuf_unref (elem->background_image);

        g_free (elem);
}


HTMLDrawQueue *
html_draw_queue_new (HTMLEngine *engine)
{
        HTMLDrawQueue *new;

        g_return_val_if_fail (engine != NULL, NULL);

        new = g_new (HTMLDrawQueue, 1);

        new->engine = engine;

        new->elems = NULL;
        new->last = NULL;

        new->clear_elems = NULL;
        new->clear_last = NULL;

        return new;
}

void
html_draw_queue_destroy (HTMLDrawQueue *queue)
{
        GList *p;

        g_return_if_fail (queue != NULL);

        for (p = queue->elems; p != NULL; p = p->next) {
                HTMLObject *obj;

                obj = p->data;
                obj->redraw_pending = FALSE;
        }

        g_list_free (queue->elems);

        g_free (queue);
}

void
html_draw_queue_add (HTMLDrawQueue *queue, HTMLObject *object)
{
        g_return_if_fail (queue != NULL);
        g_return_if_fail (object != NULL);

        if (object->redraw_pending)
                return;

        object->redraw_pending = TRUE;

        queue->last = g_list_append (queue->last, object);

        if (queue->elems == NULL && queue->clear_elems == NULL)
                g_signal_emit_by_name (queue->engine, "draw_pending");

        if (queue->elems == NULL)
                queue->elems = queue->last;
        else
                queue->last = queue->last->next;
}


static void
add_clear (HTMLDrawQueue *queue,
           HTMLDrawQueueClearElement *elem)
{
        queue->clear_last = g_list_append (queue->clear_last, elem);
        if (queue->elems == NULL && queue->clear_elems == NULL)
                g_signal_emit_by_name (queue->engine, "draw_pending");

        if (queue->clear_elems == NULL)
                queue->clear_elems = queue->clear_last;
        else
                queue->clear_last = queue->clear_last->next;
}

void
html_draw_queue_add_clear (HTMLDrawQueue *queue,
                           gint x,
                           gint y,
                           guint width,
                           guint height,
                           const GdkColor *background_color)
{
        HTMLDrawQueueClearElement *new;

        g_return_if_fail (queue != NULL);
        g_return_if_fail (background_color != NULL);

        new = clear_element_new (x, y, width, height, background_color);
        add_clear (queue, new);
}

static void
draw_obj (HTMLDrawQueue *queue,
          HTMLObject *obj)
{
        HTMLEngine *e;
        gint x1, y1, x2, y2;
        gint tx, ty;

        if (obj->width == 0 || obj->ascent + obj->descent == 0)
                return;

        e = queue->engine;
        e->clue->x = html_engine_get_left_border (e);
        e->clue->y = html_engine_get_top_border (e) + e->clue->ascent;

        html_object_engine_translation (obj, e, &tx, &ty);
        if (html_object_engine_intersection (obj, e, tx, ty, &x1, &y1, &x2, &y2)) {
                GdkRectangle paint;

                paint.x = x1;
                paint.y = y1;
                paint.width = x2 - x1;
                paint.height = y2 - y1;
                gdk_window_invalidate_rect (HTML_GDK_PAINTER (e->painter)->window, &paint, FALSE);
        } 
}

static void
clear (HTMLDrawQueue *queue,
       HTMLDrawQueueClearElement *elem)
{
        HTMLEngine *e;
        gint x1, y1, x2, y2;

        e = queue->engine;
        e->clue->x = html_engine_get_left_border (e);
        e->clue->y = html_engine_get_top_border (e) + e->clue->ascent;

        x1 = elem->x;
        y1 = elem->y;

        x2 = x1 + elem->width;
        y2 = y1 + elem->height;

        if (html_engine_intersection (e, &x1, &y1, &x2, &y2)) {
                GdkRectangle paint;

                paint.x = x1;
                paint.y = y1;
                paint.width = x2 - x1;
                paint.height = y2 - y1;
                gdk_window_invalidate_rect (HTML_GDK_PAINTER (e->painter)->window, &paint, FALSE);
        } 
}

void
html_draw_queue_clear (HTMLDrawQueue *queue)
{
        GList *p;

        for (p = queue->elems; p != NULL; p = p->next) {
                HTMLObject *obj = HTML_OBJECT (p->data);
                        
                obj->redraw_pending = FALSE;
                if (obj->free_pending) {
                        g_free (obj);
                        p->data = (gpointer)0xdeadbeef;
                }
        }

        g_list_free (queue->clear_elems);
        g_list_free (queue->elems);

        queue->clear_elems = NULL;
        queue->clear_last = NULL;
        queue->elems = NULL;
        queue->last = NULL;
}

void
html_draw_queue_flush (HTMLDrawQueue *queue)
{
        GList *p;
        GdkVisual *vis;

        /* check to make sure we have something to draw on */

        vis = queue->engine->window ? gdk_drawable_get_visual (queue->engine->window): NULL;

        /* Draw clear areas.  */

        for (p = queue->clear_elems; p != NULL; p = p->next) {
                HTMLDrawQueueClearElement *clear_elem;

                clear_elem = p->data;
                if (vis)
                        clear (queue, clear_elem);
                clear_element_destroy (clear_elem);
        }


        /* Draw objects.  */

        if (vis) {
                for (p = queue->elems; p != NULL; p = p->next) {
                        HTMLObject *obj = HTML_OBJECT (p->data);
                        
                        if (obj->redraw_pending && !obj->free_pending) {
                                draw_obj (queue, obj);
                                obj->redraw_pending = FALSE;
                        }
                }
        }
        html_draw_queue_clear (queue);
}