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authorsanine <sanine.not@pm.me>2022-10-12 13:26:36 -0500
committersanine <sanine.not@pm.me>2022-10-12 13:26:36 -0500
commitf567ea1e2798fd3156a416e61f083ea3e6b95719 (patch)
tree53b51bda93aadf9dd13fcd77635b8c4b5c813768 /libs/pixman-0.40.0/pixman/pixman-conical-gradient.c
parent530ffd0b7d3c39757b20f00716e486b5caf89aff (diff)
add pixman and libpngraylib
Diffstat (limited to 'libs/pixman-0.40.0/pixman/pixman-conical-gradient.c')
-rw-r--r--libs/pixman-0.40.0/pixman/pixman-conical-gradient.c220
1 files changed, 220 insertions, 0 deletions
diff --git a/libs/pixman-0.40.0/pixman/pixman-conical-gradient.c b/libs/pixman-0.40.0/pixman/pixman-conical-gradient.c
new file mode 100644
index 0000000..a39e20c
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+++ b/libs/pixman-0.40.0/pixman/pixman-conical-gradient.c
@@ -0,0 +1,220 @@
+/*
+ * Copyright © 2000 SuSE, Inc.
+ * Copyright © 2007 Red Hat, Inc.
+ * Copyright © 2000 Keith Packard, member of The XFree86 Project, Inc.
+ * 2005 Lars Knoll & Zack Rusin, Trolltech
+ *
+ * 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.
+ *
+ * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS
+ * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS, IN NO EVENT SHALL THE COPYRIGHT HOLDERS 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.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdlib.h>
+#include <math.h>
+#include "pixman-private.h"
+
+static force_inline double
+coordinates_to_parameter (double x, double y, double angle)
+{
+ double t;
+
+ t = atan2 (y, x) + angle;
+
+ while (t < 0)
+ t += 2 * M_PI;
+
+ while (t >= 2 * M_PI)
+ t -= 2 * M_PI;
+
+ return 1 - t * (1 / (2 * M_PI)); /* Scale t to [0, 1] and
+ * make rotation CCW
+ */
+}
+
+static uint32_t *
+conical_get_scanline (pixman_iter_t *iter,
+ const uint32_t *mask,
+ int Bpp,
+ pixman_gradient_walker_write_t write_pixel)
+{
+ pixman_image_t *image = iter->image;
+ int x = iter->x;
+ int y = iter->y;
+ int width = iter->width;
+ uint32_t *buffer = iter->buffer;
+
+ gradient_t *gradient = (gradient_t *)image;
+ conical_gradient_t *conical = (conical_gradient_t *)image;
+ uint32_t *end = buffer + width * (Bpp / 4);
+ pixman_gradient_walker_t walker;
+ pixman_bool_t affine = TRUE;
+ double cx = 1.;
+ double cy = 0.;
+ double cz = 0.;
+ double rx = x + 0.5;
+ double ry = y + 0.5;
+ double rz = 1.;
+
+ _pixman_gradient_walker_init (&walker, gradient, image->common.repeat);
+
+ if (image->common.transform)
+ {
+ pixman_vector_t v;
+
+ /* reference point is the center of the pixel */
+ v.vector[0] = pixman_int_to_fixed (x) + pixman_fixed_1 / 2;
+ v.vector[1] = pixman_int_to_fixed (y) + pixman_fixed_1 / 2;
+ v.vector[2] = pixman_fixed_1;
+
+ if (!pixman_transform_point_3d (image->common.transform, &v))
+ return iter->buffer;
+
+ cx = image->common.transform->matrix[0][0] / 65536.;
+ cy = image->common.transform->matrix[1][0] / 65536.;
+ cz = image->common.transform->matrix[2][0] / 65536.;
+
+ rx = v.vector[0] / 65536.;
+ ry = v.vector[1] / 65536.;
+ rz = v.vector[2] / 65536.;
+
+ affine =
+ image->common.transform->matrix[2][0] == 0 &&
+ v.vector[2] == pixman_fixed_1;
+ }
+
+ if (affine)
+ {
+ rx -= conical->center.x / 65536.;
+ ry -= conical->center.y / 65536.;
+
+ while (buffer < end)
+ {
+ if (!mask || *mask++)
+ {
+ double t = coordinates_to_parameter (rx, ry, conical->angle);
+
+ write_pixel (&walker,
+ (pixman_fixed_48_16_t)pixman_double_to_fixed (t),
+ buffer);
+ }
+
+ buffer += (Bpp / 4);
+
+ rx += cx;
+ ry += cy;
+ }
+ }
+ else
+ {
+ while (buffer < end)
+ {
+ double x, y;
+
+ if (!mask || *mask++)
+ {
+ double t;
+
+ if (rz != 0)
+ {
+ x = rx / rz;
+ y = ry / rz;
+ }
+ else
+ {
+ x = y = 0.;
+ }
+
+ x -= conical->center.x / 65536.;
+ y -= conical->center.y / 65536.;
+
+ t = coordinates_to_parameter (x, y, conical->angle);
+
+ write_pixel (&walker,
+ (pixman_fixed_48_16_t)pixman_double_to_fixed (t),
+ buffer);
+ }
+
+ buffer += (Bpp / 4);
+
+ rx += cx;
+ ry += cy;
+ rz += cz;
+ }
+ }
+
+ iter->y++;
+ return iter->buffer;
+}
+
+static uint32_t *
+conical_get_scanline_narrow (pixman_iter_t *iter, const uint32_t *mask)
+{
+ return conical_get_scanline (iter, mask, 4,
+ _pixman_gradient_walker_write_narrow);
+}
+
+static uint32_t *
+conical_get_scanline_wide (pixman_iter_t *iter, const uint32_t *mask)
+{
+ return conical_get_scanline (iter, NULL, 16,
+ _pixman_gradient_walker_write_wide);
+}
+
+void
+_pixman_conical_gradient_iter_init (pixman_image_t *image, pixman_iter_t *iter)
+{
+ if (iter->iter_flags & ITER_NARROW)
+ iter->get_scanline = conical_get_scanline_narrow;
+ else
+ iter->get_scanline = conical_get_scanline_wide;
+}
+
+PIXMAN_EXPORT pixman_image_t *
+pixman_image_create_conical_gradient (const pixman_point_fixed_t * center,
+ pixman_fixed_t angle,
+ const pixman_gradient_stop_t *stops,
+ int n_stops)
+{
+ pixman_image_t *image = _pixman_image_allocate ();
+ conical_gradient_t *conical;
+
+ if (!image)
+ return NULL;
+
+ conical = &image->conical;
+
+ if (!_pixman_init_gradient (&conical->common, stops, n_stops))
+ {
+ free (image);
+ return NULL;
+ }
+
+ angle = MOD (angle, pixman_int_to_fixed (360));
+
+ image->type = CONICAL;
+
+ conical->center = *center;
+ conical->angle = (pixman_fixed_to_double (angle) / 180.0) * M_PI;
+
+ return image;
+}
+