pixbuf-renderer.c

Gqview,Linux下基于GTK+库写成的轻量级而能丰富的图像浏览程序。

	pr_border_draw(pr, 0, 0, pr->window_width, pr->window_height);
}

void pixbuf_renderer_set_color(PixbufRenderer *pr, GdkColor *color)
{
	GtkStyle *style;
	GtkWidget *widget;

	g_return_if_fail(IS_PIXBUF_RENDERER(pr));

	widget = GTK_WIDGET(pr);

	style = gtk_style_copy(gtk_widget_get_style(widget));
	g_object_ref(G_OBJECT(style));

	if (color)
		{
		GdkColor *slot;

		slot = &style->bg[GTK_STATE_NORMAL];

		slot->red = color->red;
		slot->green = color->green;
		slot->blue = color->blue;
		}

	gtk_widget_set_style(widget, style);
	g_object_unref(G_OBJECT(style));

	if (GTK_WIDGET_VISIBLE(widget)) pr_border_clear(pr);
}

void pixbuf_renderer_set_black(PixbufRenderer *pr, gint black)
{
	GdkColor color = { 0, 0, 0, 0};

	pixbuf_renderer_set_color(pr, &color);
}


/*
 *-------------------------------------------------------------------
 * source tiles
 *-------------------------------------------------------------------
 */

static void pr_source_tile_free(SourceTile *st)
{
	if (!st) return;

	if (st->pixbuf) g_object_unref(st->pixbuf);
	g_free(st);
}

static void pr_source_tile_free_all(PixbufRenderer *pr)
{
	GList *work;

	work = pr->source_tiles;
	while (work)
		{
		SourceTile *st;

		st = work->data;
		work = work->next;

		pr_source_tile_free(st);
		}

	g_list_free(pr->source_tiles);
	pr->source_tiles = NULL;
}

static void pr_source_tile_unset(PixbufRenderer *pr)
{
	pr_source_tile_free_all(pr);
	pr->source_tiles_enabled = FALSE;
}

static gint pr_source_tile_visible(PixbufRenderer *pr, SourceTile *st)
{
	gint x1, y1, x2, y2;

	if (!st) return FALSE;

	x1 = (pr->x_scroll / pr->tile_width) * pr->tile_width;
	y1 = (pr->y_scroll / pr->tile_height) * pr->tile_height;
	x2 = ((pr->x_scroll + pr->vis_width) / pr->tile_width) * pr->tile_width + pr->tile_width;
	y2 = ((pr->y_scroll + pr->vis_height) / pr->tile_height) * pr->tile_height + pr->tile_height;

	return !((double)st->x * pr->scale > (double)x2 ||
		 (double)(st->x + pr->source_tile_width) * pr->scale < (double)x1 ||
		 (double)st->y * pr->scale > (double)y2 ||
		 (double)(st->y + pr->source_tile_height) * pr->scale < (double)y1);
}

static SourceTile *pr_source_tile_new(PixbufRenderer *pr, gint x, gint y)
{
	SourceTile *st = NULL;
	gint count;

	g_return_val_if_fail(pr->source_tile_width >= 1 && pr->source_tile_height >= 1, NULL);

	if (pr->source_tiles_cache_size < 4) pr->source_tiles_cache_size = 4;

	count = g_list_length(pr->source_tiles);
	if (count >= pr->source_tiles_cache_size)
		{
		GList *work;

		work = g_list_last(pr->source_tiles);
		while (work && count >= pr->source_tiles_cache_size)
			{
			SourceTile *needle;

			needle = work->data;
			work = work->prev;

			if (!pr_source_tile_visible(pr, needle))
				{
				pr->source_tiles = g_list_remove(pr->source_tiles, needle);

				if (pr->func_tile_dispose)
					{
					pr->func_tile_dispose(pr, needle->x, needle->y,
							      pr->source_tile_width, pr->source_tile_height,
							      needle->pixbuf, pr->func_tile_data);
					}

				if (!st)
					{
					st = needle;
					}
				else
					{
					pr_source_tile_free(needle);
					}

				count--;
				}
			}
		}

	if (!st)
		{
		st = g_new0(SourceTile, 1);
		st->pixbuf = gdk_pixbuf_new(GDK_COLORSPACE_RGB, FALSE, 8,
					    pr->source_tile_width, pr->source_tile_height);
		}

	st->x = (x / pr->source_tile_width) * pr->source_tile_width;
	st->y = (y / pr->source_tile_height) * pr->source_tile_height;
	st->blank = TRUE;

	pr->source_tiles = g_list_prepend(pr->source_tiles, st);

	return st;
}

static SourceTile *pr_source_tile_request(PixbufRenderer *pr, gint x, gint y)
{
	SourceTile *st;

	st = pr_source_tile_new(pr, x, y);
	if (!st) return NULL;

	if (pr->func_tile_request &&
	    pr->func_tile_request(pr, st->x, st->y,
				   pr->source_tile_width, pr->source_tile_height, st->pixbuf, pr->func_tile_data))
		{
		st->blank = FALSE;
		}

	pr_tile_invalidate_region(pr, st->x * pr->scale, st->y * pr->scale,
				  pr->source_tile_width * pr->scale, pr->source_tile_height * pr->scale);

	return st;
}

static SourceTile *pr_source_tile_find(PixbufRenderer *pr, gint x, gint y)
{
	GList *work;

	work = pr->source_tiles;
	while (work)
		{
		SourceTile *st = work->data;

		if (x >= st->x && x < st->x + pr->source_tile_width &&
		    y >= st->y && y < st->y + pr->source_tile_height)
			{
			if (work != pr->source_tiles)
				{
				pr->source_tiles = g_list_remove_link(pr->source_tiles, work);
				pr->source_tiles = g_list_concat(work, pr->source_tiles);
				}
			return st;
			}

		work = work->next;
		}

	return NULL;
}

static GList *pr_source_tile_compute_region(PixbufRenderer *pr, gint x, gint y, gint w, gint h, gint request)
{
	gint x1, y1;
	GList *list = NULL;
	gint sx, sy;

	if (x < 0) x = 0;
	if (y < 0) y = 0;
	if (w > pr->image_width) w = pr->image_width;
	if (h > pr->image_height) h = pr->image_height;

	sx = (x / pr->source_tile_width) * pr->source_tile_width;
	sy = (y / pr->source_tile_height) * pr->source_tile_height;

	for (x1 = sx; x1 < x + w; x1+= pr->source_tile_width)
		{
		for (y1 = sy; y1 < y + h; y1 += pr->source_tile_height)
			{
			SourceTile *st;

			st = pr_source_tile_find(pr, x1, y1);
			if (!st && request) st = pr_source_tile_request(pr, x1, y1);

			if (st) list = g_list_prepend(list, st);
			}
		}

	return g_list_reverse(list);
}

static void pr_source_tile_changed(PixbufRenderer *pr, gint x, gint y, gint width, gint height)
{
	GList *work;

	work = pr->source_tiles;
	while (work)
		{
		SourceTile *st;
		gint rx, ry, rw, rh;

		st = work->data;
		work = work->next;

		if (pr_clip_region(st->x, st->y, pr->source_tile_width, pr->source_tile_height,
				   x, y, width, height,
				   &rx, &ry, &rw, &rh))
			{
			GdkPixbuf *pixbuf;

			pixbuf = gdk_pixbuf_new_subpixbuf(st->pixbuf, rx - st->x, ry - st->y, rw, rh);
			if (pr->func_tile_request &&
			    pr->func_tile_request(pr, rx, ry, rw, rh, pixbuf, pr->func_tile_data))
				{
				pr_tile_invalidate_region(pr, rx * pr->scale, ry * pr->scale,
							      rw * pr->scale, rh * pr->scale);
				}
			g_object_unref(pixbuf);
			}
		}
}

static gint pr_source_tile_render(PixbufRenderer *pr, ImageTile *it,
				  gint x, gint y, gint w, gint h,
				  gint new_data, gint fast)
{
	GtkWidget *box;
	GList *list;
	GList *work;
	gint draw = FALSE;

	box = GTK_WIDGET(pr);

	if (pr->zoom == 1.0 || pr->scale == 1.0)
		{
		list = pr_source_tile_compute_region(pr, it->x + x, it->y + y, w, h, TRUE);
		work = list;
		while (work)
			{
			SourceTile *st;
			gint rx, ry, rw, rh;

			st = work->data;
			work = work->next;

			if (pr_clip_region(st->x, st->y, pr->source_tile_width, pr->source_tile_height,
					   it->x + x, it->y + y, w, h,
					   &rx, &ry, &rw, &rh))
				{
				if (st->blank)
					{
					gdk_draw_rectangle(it->pixmap, box->style->black_gc, TRUE,
							   rx - st->x, ry - st->y, rw, rh);
					}
				else /* (pr->zoom == 1.0 || pr->scale == 1.0) */
					{
					gdk_draw_pixbuf(it->pixmap,
							box->style->fg_gc[GTK_WIDGET_STATE(box)],
							st->pixbuf,
							rx - st->x, ry - st->y,
							rx - it->x, ry - it->y,
							rw, rh,
							pr->dither_quality, rx, ry);
					}
				}
			}
		}
	else
		{
		double scale_x, scale_y;
		gint sx, sy, sw, sh;

		if (pr->image_width == 0 || pr->image_height == 0) return FALSE;
		scale_x = (double)pr->width / pr->image_width;
		scale_y = (double)pr->height / pr->image_height;

		sx = (double)(it->x + x) / scale_x;
		sy = (double)(it->y + y) / scale_y;
		sw = (double)w / scale_x;
		sh = (double)h / scale_y;

		if (pr->width < PR_MIN_SCALE_SIZE || pr->height < PR_MIN_SCALE_SIZE) fast = TRUE;

#if 0
		/* draws red over draw region, to check for leaks (regions not filled) */
		pixbuf_set_rect_fill(it->pixbuf, x, y, w, h, 255, 0, 0, 255);
#endif

		list = pr_source_tile_compute_region(pr, sx, sy, sw, sh, TRUE);
		work = list;
		while (work)
			{
			SourceTile *st;
			gint rx, ry, rw, rh;
			gint stx, sty, stw, sth;

			st = work->data;
			work = work->next;

			stx = floor((double)st->x * scale_x);
			sty = floor((double)st->y * scale_y);
			stw = ceil ((double)(st->x + pr->source_tile_width) * scale_x) - stx;
			sth = ceil ((double)(st->y + pr->source_tile_height) * scale_y) - sty;

			if (pr_clip_region(stx, sty, stw, sth,
					   it->x + x, it->y + y, w, h,
					   &rx, &ry, &rw, &rh))
				{
				if (st->blank)
					{
					gdk_draw_rectangle(it->pixmap, box->style->black_gc, TRUE,
							   rx - st->x, ry - st->y, rw, rh);
					}
				else
					{
					double offset_x;
					double offset_y;

					/* may need to use unfloored stx,sty values here */
					offset_x = (double)(stx - it->x);
					offset_y = (double)(sty - it->y);

					gdk_pixbuf_scale(st->pixbuf, it->pixbuf, rx - it->x, ry - it->y, rw, rh,
						 (double) 0.0 + offset_x,
						 (double) 0.0 + offset_y,
						 scale_x, scale_y,
						 (fast) ? GDK_INTERP_NEAREST : pr->zoom_quality);
					draw = TRUE;
					}
				}
			}
		}

	g_list_free(list);

	return draw;
}

void pixbuf_renderer_set_tiles(PixbufRenderer *pr, gint width, gint height,
			       gint tile_width, gint tile_height, gint cache_size,
			       PixbufRendererTileRequestFunc func_request,
			       PixbufRendererTileDisposeFunc func_dispose,
			       gpointer user_data,
			       gdouble zoom)
{
	g_return_if_fail(IS_PIXBUF_RENDERER(pr));
	g_return_if_fail(tile_width >= 32 && tile_width >= 32);
	g_return_if_fail(width >= 32 && height > 32);
	g_return_if_fail(func_request != NULL);

	if (pr->pixbuf) g_object_unref(pr->pixbuf);
	pr->pixbuf = NULL;

	pr_source_tile_unset(pr);

	if (cache_size < 4) cache_size = 4;

	pr->source_tiles_enabled = TRUE;
	pr->source_tiles_cache_size = cache_size;
	pr->source_tile_width = tile_width;
	pr->source_tile_height = tile_height;

	pr->image_width = width;
	pr->image_height = height;

	pr->func_tile_request = func_request;
	pr->func_tile_dispose = func_dispose;
	pr->func_tile_data = user_data;

	pr_zoom_sync(pr, zoom, TRUE, FALSE, TRUE, FALSE, 0, 0);
	pr_redraw(pr, TRUE);
}

gint pixbuf_renderer_get_tiles(PixbufRenderer *pr)
{
	g_return_val_if_fail(IS_PIXBUF_RENDERER(pr), FALSE);

	return pr->source_tiles_enabled;
}

static void pr_zoom_adjust_real(PixbufRenderer *pr, gdouble increment,
				gint center_point, gint x, gint y)
{
	gdouble zoom = pr->zoom;

	if (increment == 0.0) return;

	if (zoom == 0.0)
		{
		if (pr->scale < 1.0)
			{
			zoom = 0.0 - 1.0 / pr->scale;
			}
		else
			{
			zoom = pr->scale;
			}
		}

	if (increment < 0.0)
		{
		if (zoom >= 1.0 && zoom + increment < 1.0)
			{
			zoom = zoom + increment - 2.0;
			}
		else
			{
			zoom = zoom + increment;
			}
		}
	else
		{
		if (zoom <= -1.0 && zoom + increment > -1.0)
			{
			zoom = zoom + increment + 2.0;
			}
		else
			{
			zoom = zoom + increment;
			}
		}

	pr_zoom_sync(pr, zoom, FALSE, FALSE, FALSE, center_point, x, y);
}

/*
 *-------------------------------------------------------------------
 * display tiles
 *-------------------------------------------------------------------
 */

static ImageTile *pr_tile_new(gint x, gint y, gint width, gint height)
{
	ImageTile *it;

	it = g_new0(ImageTile, 1);

	it->x = x;
	it->y = y;
	it->w = width;
	it->h = height;

	it->render_done = TILE_RENDER_NONE;

	return it;
}

static void pr_tile_free(ImageTile *it)
{
	if (!it) return;

	if (it->pixbuf) gdk_pixbuf_unref(it->pixbuf);
	if (it->pixmap) g_object_unref(it->pixmap);

	g_free(it);
}

static void pr_tile_free_all(PixbufRenderer *pr)
{
	GList *work;

	work = pr->tiles;
	while (work)
		{
		ImageTile *it;

		it = work->data;
		work = work->next;

		pr_tile_free(it);
		}

	g_list_free(pr->tiles);
	pr->tiles = NULL;
	pr->tile_cache_size = 0;
}

static ImageTile *pr_tile_add(PixbufRenderer *pr, gint x, gint y)
{
	ImageTile *it;

	it = pr_tile_new(x, y, pr->tile_width, pr->tile_height);

	if (it->x + it->w > pr->width) it->w = pr->width - it->x;
	if (it->y + it->h > pr->height) it->h = pr->height - it->y;

	pr->tiles = g_list_prepend(pr->tiles, it);
	pr->tile_cache_size += it->size;

	return it;
}

static void pr_tile_remove(PixbufRenderer *pr, ImageTile *it)
{
	if (it->qd)
		{
		QueueData *qd = it->qd;

		it->qd = NULL;
		pr->draw_queue = g_list_remove(pr->draw_queue, qd);
		g_free(qd);
		}

	if (it->qd2)
		{
		QueueData *qd = it->qd2;

		it->qd2 = NULL;
		pr->draw_queue_2pass = g_list_remove(pr->draw_queue_2pass, qd);
		g_free(qd);
		}

	pr->tiles = g_list_remove(pr->tiles, it);
	pr->tile_cache_size -= it->size;

	pr_tile_free(it);
}

static void pr_tile_free_space(PixbufRenderer *pr, guint space, ImageTile *it)
{
	GList *work;
	gint tile_max;

	work = g_list_last(pr->tiles);

	if (pr->source_tiles_enabled && pr->scale < 1.0)
		{
		gint tiles;

		tiles = (pr->vis_width / pr->tile_width + 1) * (pr->vis_height / pr->tile_height + 1);
		tile_max = MAX(tiles * pr->tile_width * pr->tile_height * 3,
			       (gint)((double)pr->tile_cache_max * 1048576.0 * pr->scale));
		}
	else
		{
		tile_max = pr->tile_cache_max * 1048576;
		}