From a8d28a6ce7e0c56dacba5d527d9134573a008902 Mon Sep 17 00:00:00 2001 From: Perberos Date: Sun, 6 Nov 2011 19:30:49 -0300 Subject: inicial --- src/zoom.c | 118 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 118 insertions(+) create mode 100644 src/zoom.c (limited to 'src/zoom.c') diff --git a/src/zoom.c b/src/zoom.c new file mode 100644 index 0000000..aa027de --- /dev/null +++ b/src/zoom.c @@ -0,0 +1,118 @@ +/* Eye of Mate image viewer - utility functions for computing zoom factors + * + * Copyright (C) 2000 The Free Software Foundation + * + * Author: Federico Mena-Quintero + * + * 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. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA. + */ + +#include +#include +#include "zoom.h" + + + +/** + * zoom_fit_size: + * @dest_width: Width of destination area. + * @dest_height: Height of destination area. + * @src_width: Width of source image. + * @src_height: Height of source image. + * @upscale_smaller: Whether to scale up images smaller than the destination size. + * @width: Return value for image width. + * @height: Return value for image height. + * + * Computes the final dimensions of an image that is to be scaled to fit to a + * certain size. If @upscale_smaller is TRUE, then images smaller than the + * destination size will be scaled up; otherwise, they will be left at their + * original size. + **/ +void +zoom_fit_size (guint dest_width, guint dest_height, + guint src_width, guint src_height, + gboolean upscale_smaller, + guint *width, guint *height) +{ + guint w, h; + + g_return_if_fail (width != NULL); + g_return_if_fail (height != NULL); + + if (src_width == 0 || src_height == 0) { + *width = 0; + *height = 0; + return; + } + + if (src_width <= dest_width && src_height <= dest_height && !upscale_smaller) { + *width = src_width; + *height = src_height; + return; + } + + w = dest_width; + h = floor ((double) (src_height * w) / src_width + 0.5); + + if (h > dest_height) { + h = dest_height; + w = floor ((double) (src_width * h) / src_height + 0.5); + } + + g_assert (w <= dest_width); + g_assert (h <= dest_height); + + *width = w; + *height = h; +} + +/** + * zoom_fit_scale: + * @dest_width: Width of destination area. + * @dest_height: Height of destination area. + * @src_width: Width of source image. + * @src_height: Height of source image. + * @upscale_smaller: Whether to scale up images smaller than the destination size. + * + * Similar to zoom_fit_size(), but returns the zoom factor of the final image + * with respect to the original image's size. + * + * Return value: Zoom factor with respect to the original size. + **/ +double +zoom_fit_scale (guint dest_width, guint dest_height, + guint src_width, guint src_height, + gboolean upscale_smaller) +{ + guint w, h; + double wfactor, hfactor; + double factor; + + if (src_width == 0 || src_height == 0) + return 1.0; + + if (dest_width == 0 || dest_height == 0) + return 0.0; + + zoom_fit_size (dest_width, dest_height, src_width, src_height, upscale_smaller, &w, &h); + + wfactor = (double) w / src_width; + hfactor = (double) h / src_height; + + factor = MIN (wfactor, hfactor); + + return factor; +} + -- cgit v1.2.1