Add core thumbnail redraw functions.

svn path=/trunk/netsurf/; revision=11715

desktop/thumbnail.c

@@ -0,0 +1,77 @@
+/*
+ * Copyright 2011 Michael Drake <tlsa@netsurf-browser.org>
+ *
+ * This file is part of NetSurf, http://www.netsurf-browser.org/
+ *
+ * NetSurf 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; version 2 of the License.
+ *
+ * NetSurf 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/** \file
+ * Core thumbnail handling (implementation).
+ */
+
+#include <assert.h>
+#include <stdbool.h>
+
+#include "content/content.h"
+#include "content/hlcache.h"
+#include "desktop/browser.h"
+#include "desktop/options.h"
+#include "desktop/plotters.h"
+#include "desktop/thumbnail.h"
+#include "utils/log.h"
+
+
+/* exported interface, documented in thumbnail.h */
+bool thumbnail_redraw(struct hlcache_handle *content,
+		int width, int height)
+{
+	struct rect clip;
+	float scale;
+
+	assert(content);
+
+	/* No selection */
+	current_redraw_browser = NULL;
+
+	/* Set clip rectangle to required thumbnail size */
+	clip.x0 = 0;
+	clip.y0 = 0;
+	clip.x1 = width;
+	clip.y1 = height;
+
+	plot.clip(&clip);
+
+	/* Plot white background */
+	plot.rectangle(clip.x0, clip.y0, clip.x1, clip.y1,
+			plot_style_fill_white);
+
+	/* Find the scale we're using */
+	scale = thumbnail_get_redraw_scale(content, width);
+
+	/* Render the content */
+	return content_redraw(content, 0, 0, width, height, &clip, scale,
+			0xFFFFFF);	
+}
+
+
+/* exported interface, documented in thumbnail.h */
+float thumbnail_get_redraw_scale(struct hlcache_handle *content, int width)
+{
+	assert(content);
+
+	if (content_get_width(content))
+		return (float)width / (float)content_get_width(content);
+	else
+		return 1.0;	
+}

desktop/thumbnail.h

@@ -0,0 +1,67 @@
+/*
+ * Copyright 2011 Michael Drake <tlsa@netsurf-browser.org>
+ *
+ * This file is part of NetSurf, http://www.netsurf-browser.org/
+ *
+ * NetSurf 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; version 2 of the License.
+ *
+ * NetSurf 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/** \file
+ * Thumbail handling (interface).
+ */
+
+#ifndef _NETSURF_DESKTOP_THUMBNAIL_H_
+#define _NETSURF_DESKTOP_THUMBNAIL_H_
+
+#include <stdbool.h>
+
+struct hlcache_handle;
+struct bitmap;
+
+
+/**
+ * Redraw a content for thumbnailing
+ *
+ * Calls the redraw function for the content, 
+ *
+ * \param  content  The content to redraw for thumbnail
+ * \param  width    The thumbnail width
+ * \param  height   The thumbnail height
+ * \return true if successful, false otherwise
+ *
+ * The thumbnail is guaranteed to be filled to its width/height extents, so
+ * there is no need to render a solid background first.
+ *
+ * Units for width and height are pixels.
+ */
+bool thumbnail_redraw(struct hlcache_handle *content,
+		int width, int height);
+
+/**
+ * Get scale at which thumbnail will be rendered for a given content and
+ * thumbnail size.
+ *
+ * \param  content  The content to redraw for thumbnail
+ * \param  width    The thumbnail width
+ * \return scale thumbnail will be rendered at
+ *
+ * Units for width and height are pixels.
+ */
+float thumbnail_get_redraw_scale(struct hlcache_handle *content, int width);
+
+
+/* In platform specific thumbnail.c. */
+bool thumbnail_create(struct hlcache_handle *content, struct bitmap *bitmap,
+		const char *url);
+
+#endif