moving from https://github.com/perberos/mate-desktop-environment

1 files changed, 421 insertions, 0 deletions

diff --git a/eel/eel-graphic-effects.c b/eel/eel-graphic-effects.c
new file mode 100644
index 00000000..c96135d8
--- /dev/null
+++ b/eel/eel-graphic-effects.c
@@ -0,0 +1,421 @@
+/* -*- 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;
+}
+