gimp/libgimpcolor/gimpcairo.c

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/* LIBGIMP - The GIMP Library
* Copyright (C) 1995-1997 Peter Mattis and Spencer Kimball
*
* gimpcairo.c
* Copyright (C) 2007 Sven Neumann <sven@gimp.org>
* 2010-2012 Michael Natterer <mitch@gimp.org>
*
* 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 3 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, see
* <https://www.gnu.org/licenses/>.
*/
#include "config.h"
#include <cairo.h>
#include <gio/gio.h>
#include <gegl.h>
#include "libgimpbase/gimpbase.h"
#include "gimpcolortypes.h"
#include "gimpcairo.h"
/**
* SECTION: gimpcairo
* @title: GimpCairo
* @short_description: Color utility functions for cairo
*
* Utility functions that make cairo easier to use with GIMP color
* data types.
**/
/**
* gimp_cairo_set_source_rgb:
* @cr: Cairo context
* @color: GimpRGB color
*
* Sets the source pattern within @cr to the solid opaque color
* described by @color.
*
* This function calls cairo_set_source_rgb() for you.
*
* Since: 2.6
**/
void
gimp_cairo_set_source_rgb (cairo_t *cr,
const GimpRGB *color)
{
cairo_set_source_rgb (cr, color->r, color->g, color->b);
}
/**
* gimp_cairo_set_source_rgba:
* @cr: Cairo context
* @color: GimpRGB color
*
* Sets the source pattern within @cr to the solid translucent color
* described by @color.
*
* This function calls cairo_set_source_rgba() for you.
*
* Since: 2.6
**/
void
gimp_cairo_set_source_rgba (cairo_t *cr,
const GimpRGB *color)
{
cairo_set_source_rgba (cr, color->r, color->g, color->b, color->a);
}
/**
* gimp_cairo_checkerboard_create:
* @cr: Cairo context
* @size: check size
* @light: light check color or %NULL to use the default light gray
* @dark: dark check color or %NULL to use the default dark gray
*
* Create a repeating checkerboard pattern.
*
* Returns: a new Cairo pattern that can be used as a source on @cr.
*
* Since: 2.6
**/
cairo_pattern_t *
gimp_cairo_checkerboard_create (cairo_t *cr,
gint size,
const GimpRGB *light,
const GimpRGB *dark)
{
cairo_t *context;
cairo_surface_t *surface;
cairo_pattern_t *pattern;
g_return_val_if_fail (cr != NULL, NULL);
g_return_val_if_fail (size > 0, NULL);
surface = cairo_surface_create_similar (cairo_get_target (cr),
CAIRO_CONTENT_COLOR,
2 * size, 2 * size);
context = cairo_create (surface);
if (light)
gimp_cairo_set_source_rgb (context, light);
else
cairo_set_source_rgb (context,
GIMP_CHECK_LIGHT, GIMP_CHECK_LIGHT, GIMP_CHECK_LIGHT);
cairo_rectangle (context, 0, 0, size, size);
cairo_rectangle (context, size, size, size, size);
cairo_fill (context);
if (dark)
gimp_cairo_set_source_rgb (context, dark);
else
cairo_set_source_rgb (context,
GIMP_CHECK_DARK, GIMP_CHECK_DARK, GIMP_CHECK_DARK);
cairo_rectangle (context, 0, size, size, size);
cairo_rectangle (context, size, 0, size, size);
cairo_fill (context);
cairo_destroy (context);
pattern = cairo_pattern_create_for_surface (surface);
cairo_pattern_set_extend (pattern, CAIRO_EXTEND_REPEAT);
cairo_surface_destroy (surface);
return pattern;
}
/**
* gimp_cairo_surface_get_format:
* @surface: a Cairo surface
*
* This function returns a #Babl format that corresponds to @surface's
* pixel format.
*
* Returns: the #Babl format of @surface.
*
* Since: 2.10
**/
const Babl *
gimp_cairo_surface_get_format (cairo_surface_t *surface)
{
g_return_val_if_fail (surface != NULL, NULL);
g_return_val_if_fail (cairo_surface_get_type (surface) ==
CAIRO_SURFACE_TYPE_IMAGE, NULL);
switch (cairo_image_surface_get_format (surface))
{
case CAIRO_FORMAT_RGB24: return babl_format ("cairo-RGB24");
case CAIRO_FORMAT_ARGB32: return babl_format ("cairo-ARGB32");
case CAIRO_FORMAT_A8: return babl_format ("cairo-A8");
default:
break;
}
g_return_val_if_reached (NULL);
}
/**
* gimp_cairo_surface_create_buffer:
* @surface: a Cairo surface
*
* This function returns a #GeglBuffer which wraps @surface's pixels.
* It must only be called on image surfaces, calling it on other surface
* types is an error.
*
* Returns: (transfer full): a #GeglBuffer
*
* Since: 2.10
**/
GeglBuffer *
gimp_cairo_surface_create_buffer (cairo_surface_t *surface)
{
const Babl *format;
gint width;
gint height;
g_return_val_if_fail (surface != NULL, NULL);
g_return_val_if_fail (cairo_surface_get_type (surface) ==
CAIRO_SURFACE_TYPE_IMAGE, NULL);
format = gimp_cairo_surface_get_format (surface);
width = cairo_image_surface_get_width (surface);
height = cairo_image_surface_get_height (surface);
return
gegl_buffer_linear_new_from_data (cairo_image_surface_get_data (surface),
format,
GEGL_RECTANGLE (0, 0, width, height),
cairo_image_surface_get_stride (surface),
(GDestroyNotify) cairo_surface_destroy,
cairo_surface_reference (surface));
}