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Diffstat (limited to 'app/core/gimp-cairo.c')
| -rw-r--r-- | app/core/gimp-cairo.c | 217 |
1 files changed, 217 insertions, 0 deletions
diff --git a/app/core/gimp-cairo.c b/app/core/gimp-cairo.c new file mode 100644 index 0000000..9d5574f --- /dev/null +++ b/app/core/gimp-cairo.c @@ -0,0 +1,217 @@ +/* GIMP - The GNU Image Manipulation Program + * Copyright (C) 1995 Spencer Kimball and Peter Mattis + * + * gimp-cairo.c + * Copyright (C) 2010-2012 Michael Natterer <mitch@gimp.org> + * + * Some code here is based on code from librsvg that was originally + * written by Raph Levien <raph@artofcode.com> for Gill. + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 3 of the License, or + * (at your option) any later version. + * + * This program 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <https://www.gnu.org/licenses/>. + */ + +#include "config.h" + +#include <cairo.h> +#include <gegl.h> +#include <gdk-pixbuf/gdk-pixbuf.h> + +#include "libgimpmath/gimpmath.h" +#include "libgimpcolor/gimpcolor.h" + +#include "core-types.h" + +#include "gimp-cairo.h" + + +#define REV (2.0 * G_PI) + + +static cairo_user_data_key_t surface_data_key = { 0, }; + + +cairo_pattern_t * +gimp_cairo_pattern_create_stipple (const GimpRGB *fg, + const GimpRGB *bg, + gint index, + gdouble offset_x, + gdouble offset_y) +{ + cairo_surface_t *surface; + cairo_pattern_t *pattern; + guchar *data; + guchar *d; + guchar fg_r, fg_g, fg_b, fg_a; + guchar bg_r, bg_g, bg_b, bg_a; + gint x, y; + + g_return_val_if_fail (fg != NULL, NULL); + g_return_val_if_fail (bg != NULL, NULL); + + data = g_malloc (8 * 8 * 4); + + gimp_rgba_get_uchar (fg, &fg_r, &fg_g, &fg_b, &fg_a); + gimp_rgba_get_uchar (bg, &bg_r, &bg_g, &bg_b, &bg_a); + + d = data; + + for (y = 0; y < 8; y++) + { + for (x = 0; x < 8; x++) + { + if ((x + y + index) % 8 >= 4) + GIMP_CAIRO_ARGB32_SET_PIXEL (d, fg_r, fg_g, fg_b, fg_a); + else + GIMP_CAIRO_ARGB32_SET_PIXEL (d, bg_r, bg_g, bg_b, bg_a); + + d += 4; + } + } + + surface = cairo_image_surface_create_for_data (data, + CAIRO_FORMAT_ARGB32, + 8, 8, 8 * 4); + cairo_surface_set_user_data (surface, &surface_data_key, + data, (cairo_destroy_func_t) g_free); + + pattern = cairo_pattern_create_for_surface (surface); + cairo_pattern_set_extend (pattern, CAIRO_EXTEND_REPEAT); + + cairo_surface_destroy (surface); + + if (offset_x != 0.0 || offset_y != 0.0) + { + cairo_matrix_t matrix; + + cairo_matrix_init_translate (&matrix, + fmod (offset_x, 8), + fmod (offset_y, 8)); + cairo_pattern_set_matrix (pattern, &matrix); + } + + return pattern; +} + +void +gimp_cairo_arc (cairo_t *cr, + gdouble center_x, + gdouble center_y, + gdouble radius, + gdouble start_angle, + gdouble slice_angle) +{ + g_return_if_fail (cr != NULL); + + if (slice_angle >= 0) + { + cairo_arc_negative (cr, center_x, center_y, radius, + - start_angle, + - start_angle - slice_angle); + } + else + { + cairo_arc (cr, center_x, center_y, radius, + - start_angle, + - start_angle - slice_angle); + } +} + +void +gimp_cairo_rounded_rectangle (cairo_t *cr, + gdouble x, + gdouble y, + gdouble width, + gdouble height, + gdouble corner_radius) +{ + g_return_if_fail (cr != NULL); + + if (width < 0.0) + { + x += width; + width = -width; + } + + if (height < 0.0) + { + y += height; + height = -height; + } + + corner_radius = CLAMP (corner_radius, 0.0, MIN (width, height) / 2.0); + + if (corner_radius == 0.0) + { + cairo_rectangle (cr, x, y, width, height); + + return; + } + + cairo_new_sub_path (cr); + + cairo_arc (cr, + x + corner_radius, y + corner_radius, + corner_radius, + 0.50 * REV, 0.75 * REV); + cairo_line_to (cr, + x + width - corner_radius, y); + + cairo_arc (cr, + x + width - corner_radius, y + corner_radius, + corner_radius, + 0.75 * REV, 1.00 * REV); + cairo_line_to (cr, + x + width, y + height - corner_radius); + + cairo_arc (cr, + x + width - corner_radius, y + height - corner_radius, + corner_radius, + 0.00 * REV, 0.25 * REV); + cairo_line_to (cr, + x + corner_radius, y + height); + + cairo_arc (cr, + x + corner_radius, y + height - corner_radius, + corner_radius, + 0.25 * REV, 0.50 * REV); + cairo_line_to (cr, + x, y + corner_radius); + + cairo_close_path (cr); +} + +void +gimp_cairo_segments (cairo_t *cr, + GimpSegment *segs, + gint n_segs) +{ + gint i; + + g_return_if_fail (cr != NULL); + g_return_if_fail (segs != NULL && n_segs > 0); + + for (i = 0; i < n_segs; i++) + { + if (segs[i].x1 == segs[i].x2) + { + cairo_move_to (cr, segs[i].x1 + 0.5, segs[i].y1 + 0.5); + cairo_line_to (cr, segs[i].x2 + 0.5, segs[i].y2 - 0.5); + } + else + { + cairo_move_to (cr, segs[i].x1 + 0.5, segs[i].y1 + 0.5); + cairo_line_to (cr, segs[i].x2 - 0.5, segs[i].y2 + 0.5); + } + } +} |