cairo/src/cairo-xlib-screen.c
Carl Worth e96f382549 Add support for 8-bit PseudoColor visuals
This support involves allocating a 16-bit grayscale ramp as well
as a 5x5x5 RGB color cube. Afterwards, the 256 colors are queried
and an array is generated mapping from r3g3b3 colors to the closest
available color. Both the queried colors and the reverse mapping
are stored in a new visual-specific cairo_xlib_visual_info_t
structure which hangs off of the cairo_xlib_screen_info_t.

Both the color-cube allocation and the distance metric could be
improved by someone sufficiently motivated, (for example, allocating
and matching in a perceptually linear color space rather than just
in RGB space). Also, making this work well in the face of a changing
color map, or in the case of GrayScale, StaticGray, or DirectColor
visuals are left entirely as exercises for the reader. StaticColor
support should be fine as is, but is entirely untested.
2008-03-20 11:51:57 -07:00

462 lines
12 KiB
C

/* Cairo - a vector graphics library with display and print output
*
* Copyright © 2005 Red Hat, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it either under the terms of the GNU Lesser General Public
* License version 2.1 as published by the Free Software Foundation
* (the "LGPL") or, at your option, under the terms of the Mozilla
* Public License Version 1.1 (the "MPL"). If you do not alter this
* notice, a recipient may use your version of this file under either
* the MPL or the LGPL.
*
* You should have received a copy of the LGPL along with this library
* in the file COPYING-LGPL-2.1; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
* You should have received a copy of the MPL along with this library
* in the file COPYING-MPL-1.1
*
* The contents of this file are subject to the Mozilla Public License
* Version 1.1 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
* OF ANY KIND, either express or implied. See the LGPL or the MPL for
* the specific language governing rights and limitations.
*
* The Original Code is the cairo graphics library.
*
* The Initial Developer of the Original Code is Red Hat, Inc.
*
* Partially on code from xftdpy.c
*
* Copyright © 2000 Keith Packard
*
* 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 appear in all copies and that both that
* copyright notice and this permission notice appear in supporting
* documentation, and that the name of Keith Packard not be used in
* advertising or publicity pertaining to distribution of the software without
* specific, written prior permission. Keith Packard makes no
* representations about the suitability of this software for any purpose. It
* is provided "as is" without express or implied warranty.
*
* KEITH PACKARD DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
* EVENT SHALL KEITH PACKARD 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.
*/
#include "cairoint.h"
#include "cairo-xlib-private.h"
#include "cairo-xlib-xrender-private.h"
#include <fontconfig/fontconfig.h>
static int
parse_boolean (const char *v)
{
char c0, c1;
c0 = *v;
if (c0 == 't' || c0 == 'T' || c0 == 'y' || c0 == 'Y' || c0 == '1')
return 1;
if (c0 == 'f' || c0 == 'F' || c0 == 'n' || c0 == 'N' || c0 == '0')
return 0;
if (c0 == 'o')
{
c1 = v[1];
if (c1 == 'n' || c1 == 'N')
return 1;
if (c1 == 'f' || c1 == 'F')
return 0;
}
return -1;
}
static cairo_bool_t
get_boolean_default (Display *dpy,
const char *option,
cairo_bool_t *value)
{
char *v;
int i;
v = XGetDefault (dpy, "Xft", option);
if (v) {
i = parse_boolean (v);
if (i >= 0) {
*value = i;
return TRUE;
}
}
return FALSE;
}
static cairo_bool_t
get_integer_default (Display *dpy,
const char *option,
int *value)
{
int i;
char *v, *e;
v = XGetDefault (dpy, "Xft", option);
if (v) {
if (FcNameConstant ((FcChar8 *) v, value))
return TRUE;
i = strtol (v, &e, 0);
if (e != v)
return TRUE;
}
return FALSE;
}
/* Old versions of fontconfig didn't have these options */
#ifndef FC_HINT_NONE
#define FC_HINT_NONE 0
#define FC_HINT_SLIGHT 1
#define FC_HINT_MEDIUM 2
#define FC_HINT_FULL 3
#endif
static void
_cairo_xlib_init_screen_font_options (Display *dpy, cairo_xlib_screen_info_t *info)
{
cairo_bool_t xft_hinting;
cairo_bool_t xft_antialias;
int xft_hintstyle;
int xft_rgba;
cairo_antialias_t antialias;
cairo_subpixel_order_t subpixel_order;
cairo_hint_style_t hint_style;
if (!get_boolean_default (dpy, "antialias", &xft_antialias))
xft_antialias = TRUE;
if (!get_boolean_default (dpy, "hinting", &xft_hinting))
xft_hinting = TRUE;
if (!get_integer_default (dpy, "hintstyle", &xft_hintstyle))
xft_hintstyle = FC_HINT_FULL;
if (!get_integer_default (dpy, "rgba", &xft_rgba))
{
xft_rgba = FC_RGBA_UNKNOWN;
#if RENDER_MAJOR > 0 || RENDER_MINOR >= 6
if (info->has_render)
{
int render_order = XRenderQuerySubpixelOrder (dpy,
XScreenNumberOfScreen (info->screen));
switch (render_order)
{
default:
case SubPixelUnknown:
xft_rgba = FC_RGBA_UNKNOWN;
break;
case SubPixelHorizontalRGB:
xft_rgba = FC_RGBA_RGB;
break;
case SubPixelHorizontalBGR:
xft_rgba = FC_RGBA_BGR;
break;
case SubPixelVerticalRGB:
xft_rgba = FC_RGBA_VRGB;
break;
case SubPixelVerticalBGR:
xft_rgba = FC_RGBA_VBGR;
break;
case SubPixelNone:
xft_rgba = FC_RGBA_NONE;
break;
}
}
#endif
}
if (xft_hinting) {
switch (xft_hintstyle) {
case FC_HINT_NONE:
hint_style = CAIRO_HINT_STYLE_NONE;
break;
case FC_HINT_SLIGHT:
hint_style = CAIRO_HINT_STYLE_SLIGHT;
break;
case FC_HINT_MEDIUM:
hint_style = CAIRO_HINT_STYLE_MEDIUM;
break;
case FC_HINT_FULL:
hint_style = CAIRO_HINT_STYLE_FULL;
break;
default:
hint_style = CAIRO_HINT_STYLE_DEFAULT;
}
} else {
hint_style = CAIRO_HINT_STYLE_NONE;
}
switch (xft_rgba) {
case FC_RGBA_RGB:
subpixel_order = CAIRO_SUBPIXEL_ORDER_RGB;
break;
case FC_RGBA_BGR:
subpixel_order = CAIRO_SUBPIXEL_ORDER_BGR;
break;
case FC_RGBA_VRGB:
subpixel_order = CAIRO_SUBPIXEL_ORDER_VRGB;
break;
case FC_RGBA_VBGR:
subpixel_order = CAIRO_SUBPIXEL_ORDER_VBGR;
break;
case FC_RGBA_UNKNOWN:
case FC_RGBA_NONE:
default:
subpixel_order = CAIRO_SUBPIXEL_ORDER_DEFAULT;
}
if (xft_antialias) {
if (subpixel_order == CAIRO_SUBPIXEL_ORDER_DEFAULT)
antialias = CAIRO_ANTIALIAS_GRAY;
else
antialias = CAIRO_ANTIALIAS_SUBPIXEL;
} else {
antialias = CAIRO_ANTIALIAS_NONE;
}
cairo_font_options_set_hint_style (&info->font_options, hint_style);
cairo_font_options_set_antialias (&info->font_options, antialias);
cairo_font_options_set_subpixel_order (&info->font_options, subpixel_order);
cairo_font_options_set_hint_metrics (&info->font_options, CAIRO_HINT_METRICS_ON);
}
cairo_xlib_screen_info_t *
_cairo_xlib_screen_info_reference (cairo_xlib_screen_info_t *info)
{
assert (CAIRO_REFERENCE_COUNT_HAS_REFERENCE (&info->ref_count));
_cairo_reference_count_inc (&info->ref_count);
return info;
}
void
_cairo_xlib_screen_info_close_display (cairo_xlib_screen_info_t *info)
{
int i;
for (i = 0; i < ARRAY_LENGTH (info->gc); i++) {
if (info->gc[i] != NULL) {
XFreeGC (info->display->display, info->gc[i]);
info->gc[i] = NULL;
}
}
}
void
_cairo_xlib_screen_info_destroy (cairo_xlib_screen_info_t *info)
{
cairo_xlib_screen_info_t **prev;
cairo_xlib_screen_info_t *list;
cairo_xlib_visual_info_t **visuals;
int i;
assert (CAIRO_REFERENCE_COUNT_HAS_REFERENCE (&info->ref_count));
if (! _cairo_reference_count_dec_and_test (&info->ref_count))
return;
CAIRO_MUTEX_LOCK (info->display->mutex);
for (prev = &info->display->screens; (list = *prev); prev = &list->next) {
if (list == info) {
*prev = info->next;
break;
}
}
visuals = _cairo_array_index (&info->visuals, 0);
for (i = 0; i < _cairo_array_num_elements (&info->visuals); i++)
free (visuals[i]);
CAIRO_MUTEX_UNLOCK (info->display->mutex);
_cairo_xlib_screen_info_close_display (info);
_cairo_xlib_display_destroy (info->display);
_cairo_array_fini (&info->visuals);
free (info);
}
cairo_xlib_screen_info_t *
_cairo_xlib_screen_info_get (Display *dpy, Screen *screen)
{
cairo_xlib_display_t *display;
cairo_xlib_screen_info_t *info = NULL, **prev;
display = _cairo_xlib_display_get (dpy);
if (display == NULL)
return NULL;
CAIRO_MUTEX_LOCK (display->mutex);
if (display->closed) {
CAIRO_MUTEX_UNLOCK (display->mutex);
goto DONE;
}
for (prev = &display->screens; (info = *prev); prev = &(*prev)->next) {
if (info->screen == screen) {
/*
* MRU the list
*/
if (prev != &display->screens) {
*prev = info->next;
info->next = display->screens;
display->screens = info;
}
break;
}
}
CAIRO_MUTEX_UNLOCK (display->mutex);
if (info != NULL) {
info = _cairo_xlib_screen_info_reference (info);
} else {
info = malloc (sizeof (cairo_xlib_screen_info_t));
if (info != NULL) {
CAIRO_REFERENCE_COUNT_INIT (&info->ref_count, 2); /* Add one for display cache */
info->display = _cairo_xlib_display_reference (display);
info->screen = screen;
info->has_render = FALSE;
_cairo_font_options_init_default (&info->font_options);
memset (info->gc, 0, sizeof (info->gc));
info->gc_needs_clip_reset = 0;
_cairo_array_init (&info->visuals,
sizeof (cairo_xlib_visual_info_t*));
if (screen) {
int event_base, error_base;
info->has_render = (XRenderQueryExtension (dpy, &event_base, &error_base) &&
(XRenderFindVisualFormat (dpy, DefaultVisual (dpy, DefaultScreen (dpy))) != 0));
_cairo_xlib_init_screen_font_options (dpy, info);
}
CAIRO_MUTEX_LOCK (display->mutex);
info->next = display->screens;
display->screens = info;
CAIRO_MUTEX_UNLOCK (display->mutex);
}
}
DONE:
_cairo_xlib_display_destroy (display);
return info;
}
static int
depth_to_index (int depth)
{
switch(depth){
case 1: return 1;
case 8: return 2;
case 12: return 3;
case 15: return 4;
case 16: return 5;
case 24: return 6;
case 30: return 7;
case 32: return 8;
}
return 0;
}
GC
_cairo_xlib_screen_get_gc (cairo_xlib_screen_info_t *info, int depth)
{
GC gc;
depth = depth_to_index (depth);
gc = info->gc[depth];
info->gc[depth] = NULL;
if (info->gc_needs_clip_reset & (1 << depth)) {
XSetClipMask(info->display->display, gc, None);
info->gc_needs_clip_reset &= ~(1 << depth);
}
return gc;
}
cairo_status_t
_cairo_xlib_screen_put_gc (cairo_xlib_screen_info_t *info, int depth, GC gc, cairo_bool_t reset_clip)
{
cairo_status_t status = CAIRO_STATUS_SUCCESS;
depth = depth_to_index (depth);
if (info->gc[depth] != NULL) {
status = _cairo_xlib_display_queue_work (info->display,
(cairo_xlib_notify_func) XFreeGC,
info->gc[depth],
NULL);
}
info->gc[depth] = gc;
if (reset_clip)
info->gc_needs_clip_reset |= 1 << depth;
else
info->gc_needs_clip_reset &= ~(1 << depth);
return status;
}
cairo_xlib_visual_info_t *
_cairo_xlib_screen_get_visual_info (cairo_xlib_screen_info_t *info,
Visual *visual)
{
cairo_xlib_visual_info_t **visuals, *ret = NULL;
cairo_status_t status;
int i;
CAIRO_MUTEX_LOCK (info->display->mutex);
visuals = _cairo_array_index (&info->visuals, 0);
for (i = 0; i < _cairo_array_num_elements (&info->visuals); i++) {
if (visuals[i]->visualid == visual->visualid) {
ret = visuals[i];
break;
}
}
CAIRO_MUTEX_UNLOCK (info->display->mutex);
if (ret)
return ret;
ret = _cairo_xlib_visual_info_create (info->display->display,
XScreenNumberOfScreen (info->screen),
visual->visualid);
if (ret == NULL)
return ret;
CAIRO_MUTEX_LOCK (info->display->mutex);
status = _cairo_array_append (&info->visuals, &ret);
CAIRO_MUTEX_UNLOCK (info->display->mutex);
if (status) {
free (ret);
ret = NULL;
}
return ret;
}