--- /dev/null
+/* GDK - The GIMP Drawing Kit
+ * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser 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.
+ */
+
+/* Color Context module
+ * Copyright 1994,1995 John L. Cwikla
+ * Copyright (C) 1997 by Ripley Software Development
+ * Copyright (C) 1997 by Federico Mena (port to Gtk/Gdk)
+ */
+
+/* Copyright 1994,1995 John L. Cwikla
+ *
+ * Permission to use, copy, modify, distribute, and sell this software
+ * and its documentation for any purpose is hereby granted without fee,
+ * provided that the above copyright notice appears in all copies and that
+ * both that copyright notice and this permission notice appear in
+ * supporting documentation, and that the name of John L. Cwikla or
+ * Wolfram Research, Inc not be used in advertising or publicity
+ * pertaining to distribution of the software without specific, written
+ * prior permission. John L. Cwikla and Wolfram Research, Inc make no
+ * representations about the suitability of this software for any
+ * purpose. It is provided "as is" without express or implied warranty.
+ *
+ * John L. Cwikla and Wolfram Research, Inc disclaim all warranties with
+ * regard to this software, including all implied warranties of
+ * merchantability and fitness, in no event shall John L. Cwikla or
+ * Wolfram Research, Inc be liable for any special, indirect or
+ * consequential damages or any damages whatsoever resulting from loss of
+ * use, data or profits, whether in an action of contract, negligence or
+ * other tortious action, arising out of or in connection with the use or
+ * performance of this software.
+ *
+ * Author:
+ * John L. Cwikla
+ * X Programmer
+ * Wolfram Research Inc.
+ *
+ * cwikla@wri.com
+ */
+
+/*
+ * Modified by the GTK+ Team and others 1997-2000. See the AUTHORS
+ * file for a list of people on the GTK+ Team. See the ChangeLog
+ * files for a list of changes. These files are distributed with
+ * GTK+ at ftp://ftp.gtk.org/pub/gtk/.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "gdkcc.h"
+#include "gdkcolor.h"
+#include "gdkprivate-fb.h"
+#include "gdkinternals.h"
+
+#define MAX_IMAGE_COLORS 256
+
+typedef struct _GdkColorContextPrivate GdkColorContextPrivate;
+
+struct _GdkColorContextPrivate
+{
+ GdkColorContext color_context;
+
+ int red_max, red_mult, green_max, green_mult, blue_max, blue_mult;
+ int base_pixel;
+};
+
+static guint
+hash_color (gconstpointer key)
+{
+ const GdkColor *color = key;
+
+ return (color->red * 33023 + color->green * 30013 + color->blue * 27011);
+}
+
+static gint
+compare_colors (gconstpointer a,
+ gconstpointer b)
+{
+ const GdkColor *aa = a;
+ const GdkColor *bb = b;
+
+ return ((aa->red == bb->red) && (aa->green == bb->green) && (aa->blue == bb->blue));
+}
+
+static void
+free_hash_entry (gpointer key,
+ gpointer value,
+ gpointer user_data)
+{
+ g_free (key); /* key and value are the same GdkColor */
+}
+
+static int
+pixel_sort (const void *a, const void *b)
+{
+ return ((GdkColor *) a)->pixel - ((GdkColor *) b)->pixel;
+}
+
+/* XXX: This function does an XQueryColors() the hard way, because there is
+ * no corresponding function in Gdk.
+ */
+
+static void
+my_x_query_colors (GdkColormap *colormap,
+ GdkColor *colors,
+ gint ncolors)
+{
+ int i;
+ guint32 pixel;
+
+ for (i = 0; i < ncolors; i++)
+ {
+ pixel = colors[i].pixel;
+ switch(colormap->visual->depth)
+ {
+ case 8:
+ colors[i] = colormap->colors[pixel];
+ break;
+ case 16:
+ case 24:
+ case 32:
+ colors[i].red = (pixel & colormap->visual->red_mask)
+ << (16 - colormap->visual->red_prec - colormap->visual->red_shift);
+ colors[i].green = (pixel & colormap->visual->green_mask)
+ << (16 - colormap->visual->green_prec - colormap->visual->green_shift);
+ colors[i].blue = (pixel & colormap->visual->blue_mask)
+ << (16 - colormap->visual->blue_prec - colormap->visual->blue_shift);
+ break;
+ default:
+ g_assert_not_reached();
+ break;
+ }
+ }
+}
+
+static void
+query_colors (GdkColorContext *cc)
+{
+ gint i;
+ GdkColorContextPrivate *ccp = (GdkColorContextPrivate *) cc;
+ cc->cmap = g_new (GdkColor, cc->num_colors);
+
+ for (i = 0; i < cc->num_colors; i++)
+ cc->cmap[i].pixel = cc->clut ? cc->clut[i] : ccp->base_pixel + i;
+
+ my_x_query_colors (cc->colormap, cc->cmap, cc->num_colors);
+
+ qsort (cc->cmap, cc->num_colors, sizeof (GdkColor), pixel_sort);
+}
+
+static void
+init_bw (GdkColorContext *cc)
+{
+ GdkColor color;
+
+ g_warning ("init_bw: failed to allocate colors, falling back to black and white");
+
+ cc->mode = GDK_CC_MODE_BW;
+
+ color.red = color.green = color.blue = 0;
+
+ if (!gdk_color_alloc (cc->colormap, &color))
+ cc->black_pixel = 0;
+ else
+ cc->black_pixel = color.pixel;
+
+ color.red = color.green = color.blue = 0xffff;
+
+ if (!gdk_color_alloc (cc->colormap, &color))
+ cc->white_pixel = cc->black_pixel ? 0 : 1;
+ else
+ cc->white_pixel = color.pixel;
+
+ cc->num_colors = 2;
+}
+
+static void
+init_gray (GdkColorContext *cc)
+{
+ GdkColorContextPrivate *ccp = (GdkColorContextPrivate *) cc;
+ GdkColor *clrs, *cstart;
+ gint i;
+ gdouble dinc;
+
+ cc->num_colors = 256;
+
+ cc->clut = g_new (gulong, cc->num_colors);
+ cstart = g_new (GdkColor, cc->num_colors);
+
+ retrygray:
+
+ dinc = 65535.0 / (cc->num_colors - 1);
+
+ clrs = cstart;
+
+ for (i = 0; i < cc->num_colors; i++)
+ {
+ clrs->red = clrs->green = clrs->blue = dinc * i;
+
+ if (!gdk_color_alloc (cc->colormap, clrs))
+ {
+ gdk_colors_free (cc->colormap, cc->clut, i, 0);
+
+ cc->num_colors /= 2;
+
+ if (cc->num_colors > 1)
+ goto retrygray;
+ else
+ {
+ g_free (cc->clut);
+ cc->clut = NULL;
+ init_bw (cc);
+ g_free (cstart);
+ return;
+ }
+ }
+
+ cc->clut[i] = clrs++->pixel;
+ }
+
+ g_free (cstart);
+
+ ccp->base_pixel = 0;
+ ccp->red_max = cc->num_colors - 1;
+ ccp->red_mult = 1;
+
+ {
+ GdkColor colr;
+
+ gdk_color_white(cc->colormap, &colr);
+ cc->white_pixel = colr.pixel;
+
+ gdk_color_black(cc->colormap, &colr);
+ cc->black_pixel = colr.pixel;
+ }
+
+ query_colors (cc);
+
+ cc->mode = GDK_CC_MODE_MY_GRAY;
+}
+
+static void
+init_color (GdkColorContext *cc)
+{
+ GdkColorContextPrivate *ccp = (GdkColorContextPrivate *) cc;
+ gint cubeval;
+ GdkColor colr;
+
+ cubeval = 1;
+ while ((cubeval * cubeval * cubeval) < cc->visual->colormap_size)
+ cubeval++;
+ cubeval--;
+
+ cc->num_colors = cubeval * cubeval * cubeval;
+
+ ccp->red_max = cubeval - 1;
+ ccp->green_max = cubeval - 1;
+ ccp->blue_max = cubeval - 1;
+ ccp->red_mult = cubeval * cubeval;
+ ccp->green_mult = cubeval;
+ ccp->blue_mult = 1;
+ ccp->base_pixel = 0;
+
+ gdk_color_white(cc->colormap, &colr);
+ cc->white_pixel = colr.pixel;
+ gdk_color_black(cc->colormap, &colr);
+ cc->black_pixel = colr.pixel;
+ cc->num_colors = cc->visual->colormap_size;
+
+ /* a CLUT for storing allocated pixel indices */
+
+ cc->max_colors = cc->num_colors;
+ cc->clut = g_new (gulong, cc->max_colors);
+
+ for (cubeval = 0; cubeval < cc->max_colors; cubeval++)
+ cc->clut[cubeval] = cubeval;
+
+ query_colors (cc);
+
+ cc->mode = GDK_CC_MODE_STD_CMAP;
+}
+
+
+static void
+init_true_color (GdkColorContext *cc)
+{
+ gulong rmask, gmask, bmask;
+
+ cc->mode = GDK_CC_MODE_TRUE;
+
+ /* Red */
+
+ rmask = cc->masks.red = cc->visual->red_mask;
+
+ cc->shifts.red = 0;
+ cc->bits.red = 0;
+
+ while (!(rmask & 1))
+ {
+ rmask >>= 1;
+ cc->shifts.red++;
+ }
+
+ while (rmask & 1)
+ {
+ rmask >>= 1;
+ cc->bits.red++;
+ }
+
+ /* Green */
+
+ gmask = cc->masks.green = cc->visual->green_mask;
+
+ cc->shifts.green = 0;
+ cc->bits.green = 0;
+
+ while (!(gmask & 1))
+ {
+ gmask >>= 1;
+ cc->shifts.green++;
+ }
+
+ while (gmask & 1)
+ {
+ gmask >>= 1;
+ cc->bits.green++;
+ }
+
+ /* Blue */
+
+ bmask = cc->masks.blue = cc->visual->blue_mask;
+
+ cc->shifts.blue = 0;
+ cc->bits.blue = 0;
+
+ while (!(bmask & 1))
+ {
+ bmask >>= 1;
+ cc->shifts.blue++;
+ }
+
+ while (bmask & 1)
+ {
+ bmask >>= 1;
+ cc->bits.blue++;
+ }
+
+ cc->num_colors = (cc->visual->red_mask | cc->visual->green_mask | cc->visual->blue_mask) + 1;
+ cc->white_pixel = 0xFFFFFFFF;
+ cc->black_pixel = 0;
+}
+
+static void
+init_direct_color (GdkColorContext *cc)
+{
+ gint n, count;
+ GdkColor *clrs, *cstart;
+ gulong rval, gval, bval;
+ gulong *rtable;
+ gulong *gtable;
+ gulong *btable;
+ gdouble dinc;
+
+ init_true_color (cc); /* for shift stuff */
+
+ rval = cc->visual->red_mask >> cc->shifts.red;
+ gval = cc->visual->green_mask >> cc->shifts.green;
+ bval = cc->visual->blue_mask >> cc->shifts.blue;
+
+ rtable = g_new (gulong, rval + 1);
+ gtable = g_new (gulong, gval + 1);
+ btable = g_new (gulong, bval + 1);
+
+ cc->max_entry = MAX (rval, gval);
+ cc->max_entry = MAX (cc->max_entry, bval);
+
+ cstart = g_new (GdkColor, cc->max_entry + 1);
+ cc->clut = g_new (gulong, cc->max_entry + 1);
+
+ retrydirect:
+
+ for (n = 0; n < rval; n++)
+ rtable[n] = rval ? (65535.0 / rval * n) : 0;
+
+ for (n = 0; n < gval; n++)
+ gtable[n] = gval ? (65535.0 / gval * n) : 0;
+
+ for (n = 0; n < bval; n++)
+ btable[n] = bval ? (65535.0 / bval * n) : 0;
+
+ cc->max_entry = MAX (rval, gval);
+ cc->max_entry = MAX (cc->max_entry, bval);
+
+ count = 0;
+ clrs = cstart;
+ cc->num_colors = (rval + 1) * (gval + 1) * (bval + 1);
+
+ for (n = 0; n < cc->max_entry; n++)
+ {
+ dinc = (double) n / cc->max_entry;
+
+ clrs->red = rtable[(int) (dinc * rval)];
+ clrs->green = gtable[(int) (dinc * gval)];
+ clrs->blue = btable[(int) (dinc * bval)];
+
+ if (gdk_color_alloc (cc->colormap, clrs))
+ {
+ cc->clut[count++] = clrs->pixel;
+ clrs++;
+ }
+ else
+ {
+ gdk_colors_free (cc->colormap, cc->clut, count, 0);
+
+ rval >>= 1;
+ gval >>= 1;
+ bval >>= 1;
+
+ cc->masks.red = (cc->masks.red >> 1) & cc->visual->red_mask;
+ cc->masks.green = (cc->masks.green >> 1) & cc->visual->green_mask;
+ cc->masks.blue = (cc->masks.blue >> 1) & cc->visual->blue_mask;
+
+ cc->shifts.red++;
+ cc->shifts.green++;
+ cc->shifts.blue++;
+
+ cc->bits.red--;
+ cc->bits.green--;
+ cc->bits.blue--;
+
+ cc->num_colors = (rval + 1) * (gval + 1) * (bval + 1);
+
+ if (cc->num_colors >1)
+ goto retrydirect;
+ else
+ {
+ g_free (cc->clut);
+ cc->clut = NULL;
+ init_bw (cc);
+ break;
+ }
+ }
+ }
+
+ /* Update allocated color count; original num_colors is max_entry, which
+ * is not necessarily the same as the really allocated number of colors.
+ */
+
+ cc->num_colors = count;
+
+ g_free (rtable);
+ g_free (gtable);
+ g_free (btable);
+ g_free (cstart);
+}
+
+static void
+init_palette (GdkColorContext *cc)
+{
+ /* restore correct mode for this cc */
+
+ switch (cc->visual->type)
+ {
+ case GDK_VISUAL_STATIC_GRAY:
+ case GDK_VISUAL_GRAYSCALE:
+ if (cc->visual->colormap_size == 2)
+ cc->mode = GDK_CC_MODE_BW;
+ else
+ cc->mode = GDK_CC_MODE_MY_GRAY;
+ break;
+
+ case GDK_VISUAL_TRUE_COLOR:
+ case GDK_VISUAL_DIRECT_COLOR:
+ cc->mode = GDK_CC_MODE_TRUE;
+ break;
+
+ case GDK_VISUAL_STATIC_COLOR:
+ case GDK_VISUAL_PSEUDO_COLOR:
+ cc->mode = GDK_CC_MODE_STD_CMAP;
+ break;
+
+ default:
+ cc->mode = GDK_CC_MODE_UNDEFINED;
+ break;
+ }
+
+ /* previous palette */
+
+ if (cc->num_palette)
+ g_free (cc->palette);
+
+ if (cc->fast_dither)
+ g_free (cc->fast_dither);
+
+ /* clear hash table if present */
+
+ if (cc->color_hash)
+ {
+ g_hash_table_foreach (cc->color_hash,
+ free_hash_entry,
+ NULL);
+ g_hash_table_destroy (cc->color_hash);
+ cc->color_hash = NULL;
+ }
+
+ cc->palette = NULL;
+ cc->num_palette = 0;
+ cc->fast_dither = NULL;
+}
+
+GdkColorContext *
+gdk_color_context_new (GdkVisual *visual,
+ GdkColormap *colormap)
+{
+ GdkColorContextPrivate *ccp;
+ gint use_private_colormap = FALSE; /* XXX: maybe restore full functionality later? */
+ GdkColorContext *cc;
+ gint retry_count;
+ GdkColormap *default_colormap;
+
+ g_assert (visual != NULL);
+ g_assert (colormap != NULL);
+
+ ccp = g_new0 (GdkColorContextPrivate, 1);
+ cc = (GdkColorContext *) ccp;
+ cc->visual = visual;
+ cc->colormap = colormap;
+ cc->clut = NULL;
+ cc->cmap = NULL;
+ cc->mode = GDK_CC_MODE_UNDEFINED;
+ cc->need_to_free_colormap = FALSE;
+
+ cc->color_hash = NULL;
+ cc->palette = NULL;
+ cc->num_palette = 0;
+ cc->fast_dither = NULL;
+
+ default_colormap = gdk_colormap_get_system ();
+
+ retry_count = 0;
+
+ while (retry_count < 2)
+ {
+ /* Only create a private colormap if the visual found isn't equal
+ * to the default visual and we don't have a private colormap,
+ * -or- if we are instructed to create a private colormap (which
+ * never is the case for XmHTML).
+ */
+
+ if (use_private_colormap
+ || ((cc->visual != gdk_visual_get_system ()) /* default visual? */
+ && (colormap == default_colormap)))
+ {
+ g_warning ("gdk_color_context_new: non-default visual detected, "
+ "using private colormap");
+
+ cc->colormap = gdk_colormap_new (cc->visual, FALSE);
+
+ cc->need_to_free_colormap = (colormap != default_colormap);
+ }
+
+ switch (visual->type)
+ {
+ case GDK_VISUAL_STATIC_GRAY:
+ case GDK_VISUAL_GRAYSCALE:
+ GDK_NOTE (COLOR_CONTEXT,
+ g_message ("gdk_color_context_new: visual class is %s\n",
+ (visual->type == GDK_VISUAL_STATIC_GRAY) ?
+ "GDK_VISUAL_STATIC_GRAY" :
+ "GDK_VISUAL_GRAYSCALE"));
+
+ if (cc->visual->colormap_size == 2)
+ init_bw (cc);
+ else
+ init_gray (cc);
+
+ break;
+
+ case GDK_VISUAL_TRUE_COLOR: /* shifts */
+ GDK_NOTE (COLOR_CONTEXT,
+ g_message ("gdk_color_context_new: visual class is GDK_VISUAL_TRUE_COLOR\n"));
+
+ init_true_color (cc);
+ break;
+
+ case GDK_VISUAL_DIRECT_COLOR: /* shifts and fake CLUT */
+ GDK_NOTE (COLOR_CONTEXT,
+ g_message ("gdk_color_context_new: visual class is GDK_VISUAL_DIRECT_COLOR\n"));
+
+ init_direct_color (cc);
+ break;
+
+ case GDK_VISUAL_STATIC_COLOR:
+ case GDK_VISUAL_PSEUDO_COLOR:
+ GDK_NOTE (COLOR_CONTEXT,
+ g_message ("gdk_color_context_new: visual class is %s\n",
+ (visual->type == GDK_VISUAL_STATIC_COLOR) ?
+ "GDK_VISUAL_STATIC_COLOR" :
+ "GDK_VISUAL_PSEUDO_COLOR"));
+
+ init_color (cc);
+ break;
+
+ default:
+ g_assert_not_reached ();
+ }
+
+ if ((cc->mode == GDK_CC_MODE_BW) && (cc->visual->depth > 1))
+ {
+ use_private_colormap = TRUE;
+ retry_count++;
+ }
+ else
+ break;
+ }
+
+ /* no. of colors allocated yet */
+
+ cc->num_allocated = 0;
+
+ GDK_NOTE (COLOR_CONTEXT,
+ g_message ("gdk_color_context_new: screen depth is %i, no. of colors is %i\n",
+ cc->visual->depth, cc->num_colors));
+
+ return (GdkColorContext *) cc;
+}
+
+GdkColorContext *
+gdk_color_context_new_mono (GdkVisual *visual,
+ GdkColormap *colormap)
+{
+ GdkColorContextPrivate *ccp;
+ GdkColorContext *cc;
+
+ g_assert (visual != NULL);
+ g_assert (colormap != NULL);
+
+ cc = g_new0 (GdkColorContext, 1);
+ ccp = (GdkColorContextPrivate *) cc;
+ cc->visual = visual;
+ cc->colormap = colormap;
+ cc->clut = NULL;
+ cc->cmap = NULL;
+ cc->mode = GDK_CC_MODE_UNDEFINED;
+ cc->need_to_free_colormap = FALSE;
+
+ init_bw (cc);
+
+ return (GdkColorContext *) cc;
+}
+
+/* This doesn't currently free black/white, hmm... */
+
+void
+gdk_color_context_free (GdkColorContext *cc)
+{
+ g_assert (cc != NULL);
+
+ if ((cc->visual->type == GDK_VISUAL_STATIC_COLOR)
+ || (cc->visual->type == GDK_VISUAL_PSEUDO_COLOR))
+ {
+ gdk_colors_free (cc->colormap, cc->clut, cc->num_allocated, 0);
+ g_free (cc->clut);
+ }
+ else if (cc->clut != NULL)
+ {
+ gdk_colors_free (cc->colormap, cc->clut, cc->num_colors, 0);
+ g_free (cc->clut);
+ }
+
+ if (cc->cmap != NULL)
+ g_free (cc->cmap);
+
+ if (cc->need_to_free_colormap)
+ gdk_colormap_unref (cc->colormap);
+
+ /* free any palette that has been associated with this GdkColorContext */
+
+ init_palette (cc);
+
+ g_free (cc);
+}
+
+gulong
+gdk_color_context_get_pixel (GdkColorContext *cc,
+ gushort red,
+ gushort green,
+ gushort blue,
+ gint *failed)
+{
+ GdkColorContextPrivate *ccp = (GdkColorContextPrivate *) cc;
+ g_assert (cc != NULL);
+ g_assert (failed != NULL);
+
+ *failed = FALSE;
+
+ switch (cc->mode)
+ {
+ case GDK_CC_MODE_BW:
+ {
+ gdouble value;
+
+ value = (red / 65535.0 * 0.30
+ + green / 65535.0 * 0.59
+ + blue / 65535.0 * 0.11);
+
+ if (value > 0.5)
+ return cc->white_pixel;
+
+ return cc->black_pixel;
+ }
+
+ case GDK_CC_MODE_MY_GRAY:
+ {
+ gulong ired, igreen, iblue;
+
+ red = red * 0.30 + green * 0.59 + blue * 0.11;
+ green = 0;
+ blue = 0;
+
+ if ((ired = red * (ccp->red_max + 1) / 0xffff) > ccp->red_max)
+ ired = ccp->red_max;
+
+ ired *= ccp->red_mult;
+
+ if ((igreen = green * (ccp->green_max + 1) / 0xffff) > ccp->green_max)
+ igreen = ccp->green_max;
+
+ igreen *= ccp->green_mult;
+
+ if ((iblue = blue * (ccp->blue_max + 1) / 0xffff) > ccp->blue_max)
+ iblue = ccp->blue_max;
+
+ iblue *= ccp->blue_mult;
+
+ if (cc->clut != NULL)
+ return cc->clut[ccp->base_pixel + ired + igreen + iblue];
+
+ return ccp->base_pixel + ired + igreen + iblue;
+ }
+
+ case GDK_CC_MODE_TRUE:
+ {
+ gulong ired, igreen, iblue;
+
+ if (cc->clut == NULL)
+ {
+ red >>= 16 - cc->bits.red;
+ green >>= 16 - cc->bits.green;
+ blue >>= 16 - cc->bits.blue;
+
+ ired = (red << cc->shifts.red) & cc->masks.red;
+ igreen = (green << cc->shifts.green) & cc->masks.green;
+ iblue = (blue << cc->shifts.blue) & cc->masks.blue;
+
+ return ired | igreen | iblue;
+ }
+
+ ired = cc->clut[red * cc->max_entry / 65535] & cc->masks.red;
+ igreen = cc->clut[green * cc->max_entry / 65535] & cc->masks.green;
+ iblue = cc->clut[blue * cc->max_entry / 65535] & cc->masks.blue;
+
+ return ired | igreen | iblue;
+ }
+
+ case GDK_CC_MODE_PALETTE:
+ return gdk_color_context_get_pixel_from_palette (cc, &red, &green, &blue, failed);
+
+ case GDK_CC_MODE_STD_CMAP:
+ default:
+ {
+ GdkColor color;
+ GdkColor *result = NULL;
+
+ color.red = red;
+ color.green = green;
+ color.blue = blue;
+
+ if (cc->color_hash)
+ result = g_hash_table_lookup (cc->color_hash, &color);
+
+ if (!result)
+ {
+ color.red = red;
+ color.green = green;
+ color.blue = blue;
+ color.pixel = 0;
+
+ if (!gdk_color_alloc (cc->colormap, &color))
+ *failed = TRUE;
+ else
+ {
+ GdkColor *cnew;
+
+ /* XXX: the following comment comes directly from
+ * XCC.c. I don't know if it is relevant for
+ * gdk_color_alloc() as it is for XAllocColor()
+ * - Federico
+ */
+ /*
+ * I can't figure this out entirely, but it *is* possible
+ * that XAllocColor succeeds, even if the number of
+ * allocations we've made exceeds the number of available
+ * colors in the current colormap. And therefore it
+ * might be necessary for us to resize the CLUT.
+ */
+
+ if (cc->num_allocated == cc->max_colors)
+ {
+ cc->max_colors *= 2;
+
+ GDK_NOTE (COLOR_CONTEXT,
+ g_message ("gdk_color_context_get_pixel: "
+ "resizing CLUT to %i entries\n",
+ cc->max_colors));
+
+ cc->clut = g_realloc (cc->clut,
+ cc->max_colors * sizeof (gulong));
+ }
+
+ /* Key and value are the same color structure */
+
+ cnew = g_new (GdkColor, 1);
+ *cnew = color;
+
+ if (!cc->color_hash)
+ cc->color_hash = g_hash_table_new (hash_color, compare_colors);
+ g_hash_table_insert (cc->color_hash, cnew, cnew);
+
+ cc->clut[cc->num_allocated] = color.pixel;
+ cc->num_allocated++;
+ return color.pixel;
+ }
+ }
+
+ return result->pixel;
+ }
+ }
+}
+
+void
+gdk_color_context_get_pixels (GdkColorContext *cc,
+ gushort *reds,
+ gushort *greens,
+ gushort *blues,
+ gint ncolors,
+ gulong *colors,
+ gint *nallocated)
+{
+ gint i, k, idx;
+ gint cmapsize, ncols = 0, nopen = 0, counter = 0;
+ gint bad_alloc = FALSE;
+ gint failed[MAX_IMAGE_COLORS], allocated[MAX_IMAGE_COLORS];
+ GdkColor defs[MAX_IMAGE_COLORS], cmap[MAX_IMAGE_COLORS];
+#ifdef G_ENABLE_DEBUG
+ gint exact_col = 0, subst_col = 0, close_col = 0, black_col = 0;
+#endif
+ g_assert (cc != NULL);
+ g_assert (reds != NULL);
+ g_assert (greens != NULL);
+ g_assert (blues != NULL);
+ g_assert (colors != NULL);
+ g_assert (nallocated != NULL);
+
+ memset (defs, 0, MAX_IMAGE_COLORS * sizeof (GdkColor));
+ memset (failed, 0, MAX_IMAGE_COLORS * sizeof (gint));
+ memset (allocated, 0, MAX_IMAGE_COLORS * sizeof (gint));
+
+ /* Will only have a value if used by the progressive image loader */
+
+ ncols = *nallocated;
+
+ *nallocated = 0;
+
+ /* First allocate all pixels */
+
+ for (i = 0; i < ncolors; i++)
+ {
+ /* colors[i] is only zero if the pixel at that location hasn't
+ * been allocated yet. This is a sanity check required for proper
+ * color allocation by the progressive image loader
+ */
+
+ if (colors[i] == 0)
+ {
+ defs[i].red = reds[i];
+ defs[i].green = greens[i];
+ defs[i].blue = blues[i];
+
+ colors[i] = gdk_color_context_get_pixel (cc, reds[i], greens[i], blues[i],
+ &bad_alloc);
+
+ /* successfully allocated, store it */
+
+ if (!bad_alloc)
+ {
+ defs[i].pixel = colors[i];
+ allocated[ncols++] = colors[i];
+ }
+ else
+ failed[nopen++] = i;
+ }
+ }
+
+ *nallocated = ncols;
+
+ /* all colors available, all done */
+
+ if ((ncols == ncolors) || (nopen == 0))
+ {
+ GDK_NOTE (COLOR_CONTEXT,
+ g_message ("gdk_color_context_get_pixels: got all %i colors; "
+ "(%i colors allocated so far)\n", ncolors, cc->num_allocated));
+
+ return;
+ }
+
+ /* The fun part. We now try to allocate the colors we couldn't allocate
+ * directly. The first step will map a color onto its nearest color
+ * that has been allocated (either by us or someone else). If any colors
+ * remain unallocated, we map these onto the colors that we have allocated
+ * ourselves.
+ */
+
+ /* read up to MAX_IMAGE_COLORS colors of the current colormap */
+
+ cmapsize = MIN (cc->num_colors, MAX_IMAGE_COLORS);
+
+ /* see if the colormap has any colors to read */
+
+ if (cmapsize < 0)
+ {
+ g_warning ("gdk_color_context_get_pixels: oops! no colors available, "
+ "your images will look *really* ugly.");
+
+ return;
+ }
+
+#ifdef G_ENABLE_DEBUG
+ exact_col = ncols;
+#endif
+
+ /* initialize pixels */
+
+ for (i = 0; i < cmapsize; i++)
+ {
+ cmap[i].pixel = i;
+ cmap[i].red = cmap[i].green = cmap[i].blue = 0;
+ }
+
+ /* read the colormap */
+
+ my_x_query_colors (cc->colormap, cmap, cmapsize);
+
+ /* get a close match for any unallocated colors */
+
+ counter = nopen;
+ nopen = 0;
+ idx = 0;
+
+ do
+ {
+ gint d, j, mdist, close, ri, gi, bi;
+ gint rd, gd, bd;
+
+ i = failed[idx];
+
+ mdist = 0x1000000;
+ close = -1;
+
+ /* Store these vals. Small performance increase as this skips three
+ * indexing operations in the loop code.
+ */
+
+ ri = reds[i];
+ gi = greens[i];
+ bi = blues[i];
+
+ /* Walk all colors in the colormap and see which one is the
+ * closest. Uses plain least squares.
+ */
+
+ for (j = 0; (j < cmapsize) && (mdist != 0); j++)
+ {
+ /* Don't replace these by shifts; the sign may get clobbered */
+
+ rd = (ri - cmap[j].red) / 256;
+ gd = (gi - cmap[j].green) / 256;
+ bd = (bi - cmap[j].blue) / 256;
+
+ d = rd * rd + gd * gd + bd * bd;
+
+ if (d < mdist)
+ {
+ close = j;
+ mdist = d;
+ }
+ }
+
+ if (close != -1)
+ {
+ rd = cmap[close].red;
+ gd = cmap[close].green;
+ bd = cmap[close].blue;
+
+ /* allocate */
+
+ colors[i] = gdk_color_context_get_pixel (cc, rd, gd, bd, &bad_alloc);
+
+ /* store */
+
+ if (!bad_alloc)
+ {
+ defs[i] = cmap[close];
+ defs[i].pixel = colors[i];
+ allocated[ncols++] = colors[i];
+#ifdef G_ENABLE_DEBUG
+ close_col++;
+#endif
+ } else
+ failed[nopen++] = i;
+ } else
+ failed[nopen++] = i;
+ /* deal with in next stage if allocation failed */
+ }
+ while (++idx < counter);
+
+ *nallocated = ncols;
+
+ /* This is the maximum no. of allocated colors. See also the nopen == 0
+ * note above.
+ */
+
+ if ((ncols == ncolors) || (nopen == 0))
+ {
+ GDK_NOTE (COLOR_CONTEXT,
+ g_message ("gdk_color_context_get_pixels: got %i colors, %i exact and "
+ "%i close (%i colors allocated so far)\n",
+ ncolors, exact_col, close_col, cc->num_allocated));
+
+ return;
+ }
+
+ /* Now map any remaining unallocated pixels into the colors we did get */
+
+ idx = 0;
+
+ do
+ {
+ gint d, mdist, close, ri, gi, bi;
+ gint j, rd, gd, bd;
+
+ i = failed[idx];
+
+ mdist = 0x1000000;
+ close = -1;
+
+ /* store */
+
+ ri = reds[i];
+ gi = greens[i];
+ bi = blues[i];
+
+ /* search allocated colors */
+
+ for (j = 0; (j < ncols) && (mdist != 0); j++)
+ {
+ k = allocated[j];
+
+ /* Don't replace these by shifts; the sign may get clobbered */
+
+ rd = (ri - defs[k].red) / 256;
+ gd = (gi - defs[k].green) / 256;
+ bd = (bi - defs[k].blue) / 256;
+
+ d = rd * rd + gd * gd + bd * bd;
+
+ if (d < mdist)
+ {
+ close = k;
+ mdist = d;
+ }
+ }
+
+ if (close < 0)
+ {
+ /* too bad, map to black */
+
+ defs[i].pixel = cc->black_pixel;
+ defs[i].red = defs[i].green = defs[i].blue = 0;
+#ifdef G_ENABLE_DEBUG
+ black_col++;
+#endif
+ }
+ else
+ {
+ defs[i] = defs[close];
+#ifdef G_ENABLE_DEBUG
+ subst_col++;
+#endif
+ }
+
+ colors[i] = defs[i].pixel;
+ }
+ while (++idx < nopen);
+
+ GDK_NOTE (COLOR_CONTEXT,
+ g_message ("gdk_color_context_get_pixels: got %i colors, %i exact, %i close, "
+ "%i substituted, %i to black (%i colors allocated so far)\n",
+ ncolors, exact_col, close_col, subst_col, black_col, cc->num_allocated));
+}
+
+void
+gdk_color_context_get_pixels_incremental (GdkColorContext *cc,
+ gushort *reds,
+ gushort *greens,
+ gushort *blues,
+ gint ncolors,
+ gint *used,
+ gulong *colors,
+ gint *nallocated)
+{
+ gint i, k, idx;
+ gint cmapsize, ncols = 0, nopen = 0, counter = 0;
+ gint bad_alloc = FALSE;
+ gint failed[MAX_IMAGE_COLORS], allocated[MAX_IMAGE_COLORS];
+ GdkColor defs[MAX_IMAGE_COLORS], cmap[MAX_IMAGE_COLORS];
+#ifdef G_ENABLE_DEBUG
+ gint exact_col = 0, subst_col = 0, close_col = 0, black_col = 0;
+#endif
+
+ g_assert (cc != NULL);
+ g_assert (reds != NULL);
+ g_assert (greens != NULL);
+ g_assert (blues != NULL);
+ g_assert (used != NULL);
+ g_assert (colors != NULL);
+ g_assert (nallocated != NULL);
+
+ memset (defs, 0, MAX_IMAGE_COLORS * sizeof (GdkColor));
+ memset (failed, 0, MAX_IMAGE_COLORS * sizeof (gint));
+ memset (allocated, 0, MAX_IMAGE_COLORS * sizeof (gint));
+
+ /* Will only have a value if used by the progressive image loader */
+
+ ncols = *nallocated;
+
+ *nallocated = 0;
+
+ /* First allocate all pixels */
+
+ for (i = 0; i < ncolors; i++)
+ {
+ /* used[i] is only -1 if the pixel at that location hasn't
+ * been allocated yet. This is a sanity check required for proper
+ * color allocation by the progressive image loader.
+ * When colors[i] == 0 it indicates the slot is available for
+ * allocation.
+ */
+
+ if (used[i] != FALSE)
+ {
+ if (colors[i] == 0)
+ {
+ defs[i].red = reds[i];
+ defs[i].green = greens[i];
+ defs[i].blue = blues[i];
+
+ colors[i] = gdk_color_context_get_pixel (cc, reds[i], greens[i], blues[i], &bad_alloc);
+
+ /* successfully allocated, store it */
+
+ if (!bad_alloc)
+ {
+ defs[i].pixel = colors[i];
+ allocated[ncols++] = colors[i];
+ }
+ else
+ failed[nopen++] = i;
+ }
+#ifdef DEBUG
+ else
+ GDK_NOTE (COLOR_CONTEXT,
+ g_message ("gdk_color_context_get_pixels_incremental: "
+ "pixel at slot %i already allocated, skipping\n", i));
+#endif
+ }
+ }
+
+ *nallocated = ncols;
+
+ if ((ncols == ncolors) || (nopen == 0))
+ {
+ GDK_NOTE (COLOR_CONTEXT,
+ g_message ("gdk_color_context_get_pixels_incremental: got all %i colors "
+ "(%i colors allocated so far)\n",
+ ncolors, cc->num_allocated));
+
+ return;
+ }
+
+ cmapsize = MIN (cc->num_colors, MAX_IMAGE_COLORS);
+
+ if (cmapsize < 0)
+ {
+ g_warning ("gdk_color_context_get_pixels_incremental: oops! "
+ "No colors available images will look *really* ugly.");
+ return;
+ }
+
+#ifdef G_ENABLE_DEBUG
+ exact_col = ncols;
+#endif
+
+ /* initialize pixels */
+
+ for (i = 0; i < cmapsize; i++)
+ {
+ cmap[i].pixel = i;
+ cmap[i].red = cmap[i].green = cmap[i].blue = 0;
+ }
+
+ /* read */
+
+ my_x_query_colors (cc->colormap, cmap, cmapsize);
+
+ /* now match any unallocated colors */
+
+ counter = nopen;
+ nopen = 0;
+ idx = 0;
+
+ do
+ {
+ gint d, j, mdist, close, ri, gi, bi;
+ gint rd, gd, bd;
+
+ i = failed[idx];
+
+ mdist = 0x1000000;
+ close = -1;
+
+ /* store */
+
+ ri = reds[i];
+ gi = greens[i];
+ bi = blues[i];
+
+ for (j = 0; (j < cmapsize) && (mdist != 0); j++)
+ {
+ /* Don't replace these by shifts; the sign may get clobbered */
+
+ rd = (ri - cmap[j].red) / 256;
+ gd = (gi - cmap[j].green) / 256;
+ bd = (bi - cmap[j].blue) / 256;
+
+ d = rd * rd + gd * gd + bd * bd;
+
+ if (d < mdist)
+ {
+ close = j;
+ mdist = d;
+ }
+ }
+
+ if (close != -1)
+ {
+ rd = cmap[close].red;
+ gd = cmap[close].green;
+ bd = cmap[close].blue;
+
+ /* allocate */
+
+ colors[i] = gdk_color_context_get_pixel (cc, rd, gd, bd, &bad_alloc);
+
+ /* store */
+
+ if (!bad_alloc)
+ {
+ defs[i] = cmap[close];
+ defs[i].pixel = colors[i];
+ allocated[ncols++] = colors[i];
+#ifdef G_ENABLE_DEBUG
+ close_col++;
+#endif
+ }
+ else
+ failed[nopen++] = i;
+ }
+ else
+ failed[nopen++] = i;
+ /* deal with in next stage if allocation failed */
+ }
+ while (++idx < counter);
+
+ *nallocated = ncols;
+
+ if ((ncols == ncolors) || (nopen == 0))
+ {
+ GDK_NOTE (COLOR_CONTEXT,
+ g_message ("gdk_color_context_get_pixels_incremental: "
+ "got %i colors, %i exact and %i close "
+ "(%i colors allocated so far)\n",
+ ncolors, exact_col, close_col, cc->num_allocated));
+
+ return;
+ }
+
+ /* map remaining unallocated pixels into colors we did get */
+
+ idx = 0;
+
+ do
+ {
+ gint d, mdist, close, ri, gi, bi;
+ gint j, rd, gd, bd;
+
+ i = failed[idx];
+
+ mdist = 0x1000000;
+ close = -1;
+
+ ri = reds[i];
+ gi = greens[i];
+ bi = blues[i];
+
+ /* search allocated colors */
+
+ for (j = 0; (j < ncols) && (mdist != 0); j++)
+ {
+ k = allocated[j];
+
+ /* downscale */
+ /* Don't replace these by shifts; the sign may get clobbered */
+
+ rd = (ri - defs[k].red) / 256;
+ gd = (gi - defs[k].green) / 256;
+ bd = (bi - defs[k].blue) / 256;
+
+ d = rd * rd + gd * gd + bd * bd;
+
+ if (d < mdist)
+ {
+ close = k;
+ mdist = d;
+ }
+ }
+
+ if (close < 0)
+ {
+ /* too bad, map to black */
+
+ defs[i].pixel = cc->black_pixel;
+ defs[i].red = defs[i].green = defs[i].blue = 0;
+#ifdef G_ENABLE_DEBUG
+ black_col++;
+#endif
+ }
+ else
+ {
+ defs[i] = defs[close];
+#ifdef G_ENABLE_DEBUG
+ subst_col++;
+#endif
+ }
+
+ colors[i] = defs[i].pixel;
+ }
+ while (++idx < nopen);
+
+ GDK_NOTE (COLOR_CONTEXT,
+ g_message ("gdk_color_context_get_pixels_incremental: "
+ "got %i colors, %i exact, %i close, %i substituted, %i to black "
+ "(%i colors allocated so far)\n",
+ ncolors, exact_col, close_col, subst_col, black_col, cc->num_allocated));
+}
+
+gint
+gdk_color_context_query_color (GdkColorContext *cc,
+ GdkColor *color)
+{
+ return gdk_color_context_query_colors (cc, color, 1);
+}
+
+gint
+gdk_color_context_query_colors (GdkColorContext *cc,
+ GdkColor *colors,
+ gint num_colors)
+{
+ gint i;
+ GdkColor *tc;
+
+ g_assert (cc != NULL);
+ g_assert (colors != NULL);
+
+ switch (cc->mode)
+ {
+ case GDK_CC_MODE_BW:
+ for (i = 0, tc = colors; i < num_colors; i++, tc++)
+ {
+ if (tc->pixel == cc->white_pixel)
+ tc->red = tc->green = tc->blue = 65535;
+ else
+ tc->red = tc->green = tc->blue = 0;
+ }
+ break;
+
+ case GDK_CC_MODE_TRUE:
+ if (cc->clut == NULL)
+ for (i = 0, tc = colors; i < num_colors; i++, tc++)
+ {
+ tc->red = ((tc->pixel & cc->masks.red) >> cc->shifts.red) << (16 - cc->bits.red);
+ tc->green = ((tc->pixel & cc->masks.green) >> cc->shifts.green) << (16 - cc->bits.green);
+ tc->blue = ((tc->pixel & cc->masks.blue) >> cc->shifts.blue) << (16 - cc->bits.blue);
+ }
+ else
+ {
+ my_x_query_colors (cc->colormap, colors, num_colors);
+ return 1;
+ }
+ break;
+
+ case GDK_CC_MODE_STD_CMAP:
+ default:
+ if (cc->cmap == NULL)
+ {
+ my_x_query_colors (cc->colormap, colors, num_colors);
+ return 1;
+ }
+ else
+ {
+ gint first, last, half;
+ gulong half_pixel;
+
+ for (i = 0, tc = colors; i < num_colors; i++)
+ {
+ first = 0;
+ last = cc->num_colors - 1;
+
+ while (first <= last)
+ {
+ half = (first + last) / 2;
+ half_pixel = cc->cmap[half].pixel;
+
+ if (tc->pixel == half_pixel)
+ {
+ tc->red = cc->cmap[half].red;
+ tc->green = cc->cmap[half].green;
+ tc->blue = cc->cmap[half].blue;
+ first = last + 1; /* false break */
+ }
+ else
+ {
+ if (tc->pixel > half_pixel)
+ first = half + 1;
+ else
+ last = half - 1;
+ }
+ }
+ }
+ return 1;
+ }
+ break;
+ }
+ return 1;
+}
+
+gint
+gdk_color_context_add_palette (GdkColorContext *cc,
+ GdkColor *palette,
+ gint num_palette)
+{
+ gint i, j, erg;
+ gushort r, g, b;
+ gulong pixel[1];
+
+ g_assert (cc != NULL);
+
+ /* initialize this palette (will also erase previous palette as well) */
+
+ init_palette (cc);
+
+ /* restore previous mode if we aren't adding a new palette */
+
+ if (num_palette == 0)
+ return 0;
+
+ /* copy incoming palette */
+
+ cc->palette = g_new0(GdkColor, num_palette);
+
+ j = 0;
+
+ for (i = 0; i < num_palette; i++)
+ {
+ erg = 0;
+ pixel[0] = 0;
+
+ /* try to allocate this color */
+
+ r = palette[i].red;
+ g = palette[i].green;
+ b = palette[i].blue;
+
+ gdk_color_context_get_pixels (cc, &r, &g, &b, 1, pixel, &erg);
+
+ /* only store if we succeed */
+
+ if (erg)
+ {
+ /* store in palette */
+
+ cc->palette[j].red = r;
+ cc->palette[j].green = g;
+ cc->palette[j].blue = b;
+ cc->palette[j].pixel = pixel[0];
+
+ /* move to next slot */
+
+ j++;
+ }
+ }
+
+ /* resize to fit */
+
+ if (j != num_palette)
+ cc->palette = g_realloc (cc->palette, j * sizeof (GdkColor));
+
+ /* clear the hash table, we don't use it when dithering */
+
+ if (cc->color_hash)
+ {
+ g_hash_table_foreach (cc->color_hash,
+ free_hash_entry,
+ NULL);
+ g_hash_table_destroy (cc->color_hash);
+ cc->color_hash = NULL;
+ }
+
+ /* store real palette size */
+
+ cc->num_palette = j;
+
+ /* switch to palette mode */
+
+ cc->mode = GDK_CC_MODE_PALETTE;
+
+ /* sort palette */
+
+ qsort (cc->palette, cc->num_palette, sizeof (GdkColor), pixel_sort);
+
+ cc->fast_dither = NULL;
+
+ return j;
+}
+
+void
+gdk_color_context_init_dither (GdkColorContext *cc)
+{
+ gint rr, gg, bb, err, erg, erb;
+ gint success = FALSE;
+
+ g_assert (cc != NULL);
+
+ /* now we can initialize the fast dither matrix */
+
+ if (cc->fast_dither == NULL)
+ cc->fast_dither = g_new (GdkColorContextDither, 1);
+
+ /* Fill it. We ignore unsuccessful allocations, they are just mapped
+ * to black instead */
+
+ for (rr = 0; rr < 32; rr++)
+ for (gg = 0; gg < 32; gg++)
+ for (bb = 0; bb < 32; bb++)
+ {
+ err = (rr << 3) | (rr >> 2);
+ erg = (gg << 3) | (gg >> 2);
+ erb = (bb << 3) | (bb >> 2);
+
+ cc->fast_dither->fast_rgb[rr][gg][bb] =
+ gdk_color_context_get_index_from_palette (cc, &err, &erg, &erb, &success);
+ cc->fast_dither->fast_err[rr][gg][bb] = err;
+ cc->fast_dither->fast_erg[rr][gg][bb] = erg;
+ cc->fast_dither->fast_erb[rr][gg][bb] = erb;
+ }
+}
+
+void
+gdk_color_context_free_dither (GdkColorContext *cc)
+{
+ g_assert (cc != NULL);
+
+ if (cc->fast_dither)
+ g_free (cc->fast_dither);
+
+ cc->fast_dither = NULL;
+}
+
+gulong
+gdk_color_context_get_pixel_from_palette (GdkColorContext *cc,
+ gushort *red,
+ gushort *green,
+ gushort *blue,
+ gint *failed)
+{
+ gulong pixel = 0;
+ gint dif, dr, dg, db, j = -1;
+ gint mindif = 0x7fffffff;
+ gint err = 0, erg = 0, erb = 0;
+ gint i;
+
+ g_assert (cc != NULL);
+ g_assert (red != NULL);
+ g_assert (green != NULL);
+ g_assert (blue != NULL);
+ g_assert (failed != NULL);
+
+ *failed = FALSE;
+
+ for (i = 0; i < cc->num_palette; i++)
+ {
+ dr = *red - cc->palette[i].red;
+ dg = *green - cc->palette[i].green;
+ db = *blue - cc->palette[i].blue;
+
+ dif = dr * dr + dg * dg + db * db;
+
+ if (dif < mindif)
+ {
+ mindif = dif;
+ j = i;
+ pixel = cc->palette[i].pixel;
+ err = dr;
+ erg = dg;
+ erb = db;
+
+ if (mindif == 0)
+ break;
+ }
+ }
+
+ /* we failed to map onto a color */
+
+ if (j == -1)
+ *failed = TRUE;
+ else
+ {
+ *red = ABS (err);
+ *green = ABS (erg);
+ *blue = ABS (erb);
+ }
+
+ return pixel;
+}
+
+guchar
+gdk_color_context_get_index_from_palette (GdkColorContext *cc,
+ gint *red,
+ gint *green,
+ gint *blue,
+ gint *failed)
+{
+ gint dif, dr, dg, db, j = -1;
+ gint mindif = 0x7fffffff;
+ gint err = 0, erg = 0, erb = 0;
+ gint i;
+
+ g_assert (cc != NULL);
+ g_assert (red != NULL);
+ g_assert (green != NULL);
+ g_assert (blue != NULL);
+ g_assert (failed != NULL);
+
+ *failed = FALSE;
+
+ for (i = 0; i < cc->num_palette; i++)
+ {
+ dr = *red - cc->palette[i].red;
+ dg = *green - cc->palette[i].green;
+ db = *blue - cc->palette[i].blue;
+
+ dif = dr * dr + dg * dg + db * db;
+
+ if (dif < mindif)
+ {
+ mindif = dif;
+ j = i;
+ err = dr;
+ erg = dg;
+ erb = db;
+
+ if (mindif == 0)
+ break;
+ }
+ }
+
+ /* we failed to map onto a color */
+
+ if (j == -1)
+ {
+ *failed = TRUE;
+ j = 0;
+ }
+ else
+ {
+ /* return error fractions */
+
+ *red = err;
+ *green = erg;
+ *blue = erb;
+ }
+
+ return j;
+}
projects / gtk4.git / commitdiff