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diff --git a/eel/eel-graphic-effects.c b/eel/eel-graphic-effects.c
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+/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*- */
+
+/* Eel - pixbuf manipulation routines for graphical effects.
+ *
+ * Copyright (C) 2000 Eazel, Inc
+ *
+ * Author: Andy Hertzfeld <[email protected]>
+ *
+ * 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; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+/* This file contains pixbuf manipulation routines used for graphical effects like pre-lighting
+ and selection hilighting */
+
+#include <config.h>
+#include "eel-graphic-effects.h"
+#include <string.h>
+
+/* shared utility to create a new pixbuf from the passed-in one */
+
+static GdkPixbuf *
+create_new_pixbuf (GdkPixbuf *src)
+{
+ g_assert (gdk_pixbuf_get_colorspace (src) == GDK_COLORSPACE_RGB);
+ g_assert ((!gdk_pixbuf_get_has_alpha (src)
+ && gdk_pixbuf_get_n_channels (src) == 3)
+ || (gdk_pixbuf_get_has_alpha (src)
+ && gdk_pixbuf_get_n_channels (src) == 4));
+
+ return gdk_pixbuf_new (gdk_pixbuf_get_colorspace (src),
+ gdk_pixbuf_get_has_alpha (src),
+ gdk_pixbuf_get_bits_per_sample (src),
+ gdk_pixbuf_get_width (src),
+ gdk_pixbuf_get_height (src));
+}
+
+static GdkPixbuf *
+create_new_pixbuf_with_alpha (GdkPixbuf *src)
+{
+ g_assert (gdk_pixbuf_get_colorspace (src) == GDK_COLORSPACE_RGB);
+ g_assert ((!gdk_pixbuf_get_has_alpha (src)
+ && gdk_pixbuf_get_n_channels (src) == 3)
+ || (gdk_pixbuf_get_has_alpha (src)
+ && gdk_pixbuf_get_n_channels (src) == 4));
+
+ return gdk_pixbuf_new (gdk_pixbuf_get_colorspace (src),
+ TRUE,
+ gdk_pixbuf_get_bits_per_sample (src),
+ gdk_pixbuf_get_width (src),
+ gdk_pixbuf_get_height (src));
+}
+
+/* utility routine to bump the level of a color component with pinning */
+
+static guchar
+lighten_component (guchar cur_value)
+{
+ int new_value = cur_value;
+ new_value += 24 + (new_value >> 3);
+ if (new_value > 255)
+ {
+ new_value = 255;
+ }
+ return (guchar) new_value;
+}
+
+GdkPixbuf *
+eel_create_spotlight_pixbuf (GdkPixbuf* src)
+{
+ GdkPixbuf *dest;
+ int i, j;
+ int width, height, has_alpha, src_row_stride, dst_row_stride;
+ guchar *target_pixels, *original_pixels;
+ guchar *pixsrc, *pixdest;
+
+ g_return_val_if_fail (gdk_pixbuf_get_colorspace (src) == GDK_COLORSPACE_RGB, NULL);
+ g_return_val_if_fail ((!gdk_pixbuf_get_has_alpha (src)
+ && gdk_pixbuf_get_n_channels (src) == 3)
+ || (gdk_pixbuf_get_has_alpha (src)
+ && gdk_pixbuf_get_n_channels (src) == 4), NULL);
+ g_return_val_if_fail (gdk_pixbuf_get_bits_per_sample (src) == 8, NULL);
+
+ dest = create_new_pixbuf (src);
+
+ has_alpha = gdk_pixbuf_get_has_alpha (src);
+ width = gdk_pixbuf_get_width (src);
+ height = gdk_pixbuf_get_height (src);
+ dst_row_stride = gdk_pixbuf_get_rowstride (dest);
+ src_row_stride = gdk_pixbuf_get_rowstride (src);
+ target_pixels = gdk_pixbuf_get_pixels (dest);
+ original_pixels = gdk_pixbuf_get_pixels (src);
+
+ for (i = 0; i < height; i++)
+ {
+ pixdest = target_pixels + i * dst_row_stride;
+ pixsrc = original_pixels + i * src_row_stride;
+ for (j = 0; j < width; j++)
+ {
+ *pixdest++ = lighten_component (*pixsrc++);
+ *pixdest++ = lighten_component (*pixsrc++);
+ *pixdest++ = lighten_component (*pixsrc++);
+ if (has_alpha)
+ {
+ *pixdest++ = *pixsrc++;
+ }
+ }
+ }
+ return dest;
+}
+
+
+/* the following routine was stolen from the panel to darken a pixbuf, by manipulating the saturation */
+
+/* saturation is 0-255, darken is 0-255 */
+
+GdkPixbuf *
+eel_create_darkened_pixbuf (GdkPixbuf *src, int saturation, int darken)
+{
+ gint i, j;
+ gint width, height, src_row_stride, dest_row_stride;
+ gboolean has_alpha;
+ guchar *target_pixels, *original_pixels;
+ guchar *pixsrc, *pixdest;
+ guchar intensity;
+ guchar alpha;
+ guchar negalpha;
+ guchar r, g, b;
+ GdkPixbuf *dest;
+
+ g_return_val_if_fail (gdk_pixbuf_get_colorspace (src) == GDK_COLORSPACE_RGB, NULL);
+ g_return_val_if_fail ((!gdk_pixbuf_get_has_alpha (src)
+ && gdk_pixbuf_get_n_channels (src) == 3)
+ || (gdk_pixbuf_get_has_alpha (src)
+ && gdk_pixbuf_get_n_channels (src) == 4), NULL);
+ g_return_val_if_fail (gdk_pixbuf_get_bits_per_sample (src) == 8, NULL);
+
+ dest = create_new_pixbuf (src);
+
+ has_alpha = gdk_pixbuf_get_has_alpha (src);
+ width = gdk_pixbuf_get_width (src);
+ height = gdk_pixbuf_get_height (src);
+ dest_row_stride = gdk_pixbuf_get_rowstride (dest);
+ src_row_stride = gdk_pixbuf_get_rowstride (src);
+ target_pixels = gdk_pixbuf_get_pixels (dest);
+ original_pixels = gdk_pixbuf_get_pixels (src);
+
+ for (i = 0; i < height; i++)
+ {
+ pixdest = target_pixels + i * dest_row_stride;
+ pixsrc = original_pixels + i * src_row_stride;
+ for (j = 0; j < width; j++)
+ {
+ r = *pixsrc++;
+ g = *pixsrc++;
+ b = *pixsrc++;
+ intensity = (r * 77 + g * 150 + b * 28) >> 8;
+ negalpha = ((255 - saturation) * darken) >> 8;
+ alpha = (saturation * darken) >> 8;
+ *pixdest++ = (negalpha * intensity + alpha * r) >> 8;
+ *pixdest++ = (negalpha * intensity + alpha * g) >> 8;
+ *pixdest++ = (negalpha * intensity + alpha * b) >> 8;
+ if (has_alpha)
+ {
+ *pixdest++ = *pixsrc++;
+ }
+ }
+ }
+ return dest;
+}
+
+/* this routine colorizes the passed-in pixbuf by multiplying each pixel with the passed in color */
+
+GdkPixbuf *
+eel_create_colorized_pixbuf (GdkPixbuf *src,
+ int red_value,
+ int green_value,
+ int blue_value)
+{
+ int i, j;
+ int width, height, has_alpha, src_row_stride, dst_row_stride;
+ guchar *target_pixels;
+ guchar *original_pixels;
+ guchar *pixsrc;
+ guchar *pixdest;
+ GdkPixbuf *dest;
+
+ g_return_val_if_fail (gdk_pixbuf_get_colorspace (src) == GDK_COLORSPACE_RGB, NULL);
+ g_return_val_if_fail ((!gdk_pixbuf_get_has_alpha (src)
+ && gdk_pixbuf_get_n_channels (src) == 3)
+ || (gdk_pixbuf_get_has_alpha (src)
+ && gdk_pixbuf_get_n_channels (src) == 4), NULL);
+ g_return_val_if_fail (gdk_pixbuf_get_bits_per_sample (src) == 8, NULL);
+
+ dest = create_new_pixbuf (src);
+
+ has_alpha = gdk_pixbuf_get_has_alpha (src);
+ width = gdk_pixbuf_get_width (src);
+ height = gdk_pixbuf_get_height (src);
+ src_row_stride = gdk_pixbuf_get_rowstride (src);
+ dst_row_stride = gdk_pixbuf_get_rowstride (dest);
+ target_pixels = gdk_pixbuf_get_pixels (dest);
+ original_pixels = gdk_pixbuf_get_pixels (src);
+
+ for (i = 0; i < height; i++)
+ {
+ pixdest = target_pixels + i*dst_row_stride;
+ pixsrc = original_pixels + i*src_row_stride;
+ for (j = 0; j < width; j++)
+ {
+ *pixdest++ = (*pixsrc++ * red_value) >> 8;
+ *pixdest++ = (*pixsrc++ * green_value) >> 8;
+ *pixdest++ = (*pixsrc++ * blue_value) >> 8;
+ if (has_alpha)
+ {
+ *pixdest++ = *pixsrc++;
+ }
+ }
+ }
+ return dest;
+}
+
+/* utility to stretch a frame to the desired size */
+
+static void
+draw_frame_row (GdkPixbuf *frame_image, int target_width, int source_width, int source_v_position, int dest_v_position, GdkPixbuf *result_pixbuf, int left_offset, int height)
+{
+ int remaining_width, h_offset, slab_width;
+
+ remaining_width = target_width;
+ h_offset = 0;
+ while (remaining_width > 0)
+ {
+ slab_width = remaining_width > source_width ? source_width : remaining_width;
+ gdk_pixbuf_copy_area (frame_image, left_offset, source_v_position, slab_width, height, result_pixbuf, left_offset + h_offset, dest_v_position);
+ remaining_width -= slab_width;
+ h_offset += slab_width;
+ }
+}
+
+/* utility to draw the middle section of the frame in a loop */
+static void
+draw_frame_column (GdkPixbuf *frame_image, int target_height, int source_height, int source_h_position, int dest_h_position, GdkPixbuf *result_pixbuf, int top_offset, int width)
+{
+ int remaining_height, v_offset, slab_height;
+
+ remaining_height = target_height;
+ v_offset = 0;
+ while (remaining_height > 0)
+ {
+ slab_height = remaining_height > source_height ? source_height : remaining_height;
+ gdk_pixbuf_copy_area (frame_image, source_h_position, top_offset, width, slab_height, result_pixbuf, dest_h_position, top_offset + v_offset);
+ remaining_height -= slab_height;
+ v_offset += slab_height;
+ }
+}
+
+GdkPixbuf *
+eel_stretch_frame_image (GdkPixbuf *frame_image, int left_offset, int top_offset, int right_offset, int bottom_offset,
+ int dest_width, int dest_height, gboolean fill_flag)
+{
+ GdkPixbuf *result_pixbuf;
+ guchar *pixels_ptr;
+ int frame_width, frame_height;
+ int y, row_stride;
+ int target_width, target_frame_width;
+ int target_height, target_frame_height;
+
+ frame_width = gdk_pixbuf_get_width (frame_image);
+ frame_height = gdk_pixbuf_get_height (frame_image );
+
+ if (fill_flag)
+ {
+ result_pixbuf = gdk_pixbuf_scale_simple (frame_image, dest_width, dest_height, GDK_INTERP_NEAREST);
+ }
+ else
+ {
+ result_pixbuf = gdk_pixbuf_new (GDK_COLORSPACE_RGB, TRUE, 8, dest_width, dest_height);
+ }
+ row_stride = gdk_pixbuf_get_rowstride (result_pixbuf);
+ pixels_ptr = gdk_pixbuf_get_pixels (result_pixbuf);
+
+ /* clear the new pixbuf */
+ if (!fill_flag)
+ {
+ for (y = 0; y < dest_height; y++)
+ {
+ memset (pixels_ptr, 255, row_stride);
+ pixels_ptr += row_stride;
+ }
+ }
+
+ target_width = dest_width - left_offset - right_offset;
+ target_frame_width = frame_width - left_offset - right_offset;
+
+ target_height = dest_height - top_offset - bottom_offset;
+ target_frame_height = frame_height - top_offset - bottom_offset;
+
+ /* draw the left top corner and top row */
+ gdk_pixbuf_copy_area (frame_image, 0, 0, left_offset, top_offset, result_pixbuf, 0, 0);
+ draw_frame_row (frame_image, target_width, target_frame_width, 0, 0, result_pixbuf, left_offset, top_offset);
+
+ /* draw the right top corner and left column */
+ gdk_pixbuf_copy_area (frame_image, frame_width - right_offset, 0, right_offset, top_offset, result_pixbuf, dest_width - right_offset, 0);
+ draw_frame_column (frame_image, target_height, target_frame_height, 0, 0, result_pixbuf, top_offset, left_offset);
+
+ /* draw the bottom right corner and bottom row */
+ gdk_pixbuf_copy_area (frame_image, frame_width - right_offset, frame_height - bottom_offset, right_offset, bottom_offset, result_pixbuf, dest_width - right_offset, dest_height - bottom_offset);
+ draw_frame_row (frame_image, target_width, target_frame_width, frame_height - bottom_offset, dest_height - bottom_offset, result_pixbuf, left_offset, bottom_offset);
+
+ /* draw the bottom left corner and the right column */
+ gdk_pixbuf_copy_area (frame_image, 0, frame_height - bottom_offset, left_offset, bottom_offset, result_pixbuf, 0, dest_height - bottom_offset);
+ draw_frame_column (frame_image, target_height, target_frame_height, frame_width - right_offset, dest_width - right_offset, result_pixbuf, top_offset, right_offset);
+
+ return result_pixbuf;
+}
+
+
+/* draw an arbitrary frame around an image, with the result passed back in a newly allocated pixbuf */
+GdkPixbuf *
+eel_embed_image_in_frame (GdkPixbuf *source_image, GdkPixbuf *frame_image, int left_offset, int top_offset, int right_offset, int bottom_offset)
+{
+ GdkPixbuf *result_pixbuf;
+ int source_width, source_height;
+ int dest_width, dest_height;
+
+ source_width = gdk_pixbuf_get_width (source_image);
+ source_height = gdk_pixbuf_get_height (source_image);
+
+ dest_width = source_width + left_offset + right_offset;
+ dest_height = source_height + top_offset + bottom_offset;
+
+ result_pixbuf = eel_stretch_frame_image (frame_image, left_offset, top_offset, right_offset, bottom_offset,
+ dest_width, dest_height, FALSE);
+
+ /* Finally, copy the source image into the framed area */
+ gdk_pixbuf_copy_area (source_image, 0, 0, source_width, source_height, result_pixbuf, left_offset, top_offset);
+
+ return result_pixbuf;
+}
+
+
+/* this routine takes the source pixbuf and returns a new one that's semi-transparent, by
+ clearing every other pixel's alpha value in a checkerboard grip. We have to do the
+ checkerboard instead of reducing the alpha since it will be turned into an alpha-less
+ gdkpixmap and mask for the actual dragging */
+
+GdkPixbuf *
+eel_make_semi_transparent (GdkPixbuf *src)
+{
+ gint i, j, temp_alpha;
+ gint width, height, has_alpha, src_row_stride, dst_row_stride;
+ guchar *target_pixels, *original_pixels;
+ guchar *pixsrc, *pixdest;
+ guchar alpha_value;
+ GdkPixbuf *dest_pixbuf;
+ guchar start_alpha_value;
+
+ g_return_val_if_fail (gdk_pixbuf_get_colorspace (src) == GDK_COLORSPACE_RGB, NULL);
+ g_return_val_if_fail ((!gdk_pixbuf_get_has_alpha (src)
+ && gdk_pixbuf_get_n_channels (src) == 3)
+ || (gdk_pixbuf_get_has_alpha (src)
+ && gdk_pixbuf_get_n_channels (src) == 4), NULL);
+ g_return_val_if_fail (gdk_pixbuf_get_bits_per_sample (src) == 8, NULL);
+
+ dest_pixbuf = create_new_pixbuf_with_alpha (src);
+
+ has_alpha = gdk_pixbuf_get_has_alpha (src);
+ width = gdk_pixbuf_get_width (src);
+ height = gdk_pixbuf_get_height (src);
+ src_row_stride = gdk_pixbuf_get_rowstride (src);
+ dst_row_stride = gdk_pixbuf_get_rowstride (dest_pixbuf);
+
+ /* set up pointers to the actual pixels */
+ target_pixels = gdk_pixbuf_get_pixels (dest_pixbuf);
+ original_pixels = gdk_pixbuf_get_pixels (src);
+
+ /* loop through the pixels to do the actual work, copying from the source to the destination */
+ start_alpha_value = ~0;
+ for (i = 0; i < height; i++)
+ {
+ pixdest = target_pixels + i * dst_row_stride;
+ pixsrc = original_pixels + i * src_row_stride;
+ alpha_value = start_alpha_value;
+ for (j = 0; j < width; j++)
+ {
+ *pixdest++ = *pixsrc++; /* red */
+ *pixdest++ = *pixsrc++; /* green */
+ *pixdest++ = *pixsrc++; /* blue */
+
+ if (has_alpha)
+ {
+ temp_alpha = *pixsrc++;
+ }
+ else
+ {
+ temp_alpha = ~0;
+ }
+ *pixdest++ = temp_alpha & alpha_value;
+
+ alpha_value = ~alpha_value;
+ }
+
+ start_alpha_value = ~start_alpha_value;
+ }
+
+ return dest_pixbuf;
+}
+