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-rw-r--r--plug-ins/gfig/gfig-circle.c234
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diff --git a/plug-ins/gfig/gfig-circle.c b/plug-ins/gfig/gfig-circle.c
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+++ b/plug-ins/gfig/gfig-circle.c
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+/*
+ * Copyright (C) 1995 Spencer Kimball and Peter Mattis
+ *
+ * This is a plug-in for GIMP.
+ *
+ * Generates images containing vector type drawings.
+ *
+ * Copyright (C) 1997 Andy Thomas alt@picnic.demon.co.uk
+ *
+ * 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 <libgimp/gimp.h>
+#include <libgimp/gimpui.h>
+
+#include "gfig.h"
+#include "gfig-dobject.h"
+#include "gfig-poly.h"
+#include "gfig-circle.h"
+
+#include "libgimp/stdplugins-intl.h"
+
+static gint calc_radius (GdkPoint *center,
+ GdkPoint *edge);
+static void d_draw_circle (GfigObject *obj,
+ cairo_t *cr);
+static void d_paint_circle (GfigObject *obj);
+static GfigObject *d_copy_circle (GfigObject *obj);
+
+static void d_update_circle (GdkPoint *pnt);
+
+static gint
+calc_radius (GdkPoint *center, GdkPoint *edge)
+{
+ gint dx = center->x - edge->x;
+ gint dy = center->y - edge->y;
+
+ return (gint) sqrt (dx * dx + dy * dy);
+}
+
+static void
+d_draw_circle (GfigObject *obj,
+ cairo_t *cr)
+{
+ DobjPoints *center_pnt;
+ DobjPoints *edge_pnt;
+ gint radius;
+
+ center_pnt = obj->points;
+
+ if (!center_pnt)
+ return; /* End-of-line */
+
+ draw_sqr (&center_pnt->pnt, obj == gfig_context->selected_obj, cr);
+
+ edge_pnt = center_pnt->next;
+
+ if (!edge_pnt)
+ return;
+
+ radius = calc_radius (&center_pnt->pnt, &edge_pnt->pnt);
+
+ if (obj_creating == obj)
+ draw_circle (&edge_pnt->pnt, TRUE, cr);
+ else
+ draw_sqr (&edge_pnt->pnt, obj == gfig_context->selected_obj, cr);
+
+ gfig_draw_arc (center_pnt->pnt.x, center_pnt->pnt.y,
+ radius, radius, 0, 360, cr);
+}
+
+static void
+d_paint_circle (GfigObject *obj)
+{
+ DobjPoints *center_pnt;
+ DobjPoints *edge_pnt;
+ gint radius;
+ gdouble dpnts[4];
+
+ g_assert (obj != NULL);
+
+ center_pnt = obj->points;
+
+ if (!center_pnt)
+ return; /* End-of-line */
+
+ edge_pnt = center_pnt->next;
+
+ if (!edge_pnt)
+ {
+ g_error ("Internal error - circle no edge pnt");
+ }
+
+ radius = calc_radius (&center_pnt->pnt, &edge_pnt->pnt);
+
+ dpnts[0] = (gdouble) center_pnt->pnt.x - radius;
+ dpnts[1] = (gdouble) center_pnt->pnt.y - radius;
+ dpnts[3] = dpnts[2] = (gdouble) radius * 2;
+
+ /* Scale before drawing */
+ if (selvals.scaletoimage)
+ scale_to_original_xy (&dpnts[0], 2);
+ else
+ scale_to_xy (&dpnts[0], 2);
+
+ if (gfig_context_get_current_style ()->fill_type != FILL_NONE)
+ {
+ gimp_context_push ();
+ gimp_context_set_antialias (selopt.antia);
+ gimp_context_set_feather (selopt.feather);
+ gimp_context_set_feather_radius (selopt.feather_radius, selopt.feather_radius);
+ gimp_image_select_ellipse (gfig_context->image_id,
+ selopt.type,
+ dpnts[0], dpnts[1],
+ dpnts[2], dpnts[3]);
+ gimp_context_pop ();
+
+ paint_layer_fill (center_pnt->pnt.x - radius,
+ center_pnt->pnt.y - radius,
+ center_pnt->pnt.x + radius,
+ center_pnt->pnt.y + radius);
+ gimp_selection_none (gfig_context->image_id);
+ }
+
+ /* Drawing a circle may be harder than stroking a circular selection,
+ * but we have to do it or we will not be able to draw outside of the
+ * layer. */
+ if (obj->style.paint_type == PAINT_BRUSH_TYPE)
+ {
+ const gdouble r = dpnts[2] / 2;
+ const gdouble cx = dpnts[0] + r, cy = dpnts[1] + r;
+ gdouble line_pnts[362];
+ gdouble angle = 0;
+ gint i = 0;
+
+ while (i < 361)
+ {
+ static const gdouble step = 2 * G_PI / 180;
+
+ line_pnts[i++] = cx + r * cos (angle);
+ line_pnts[i++] = cy + r * sin (angle);
+ angle += step;
+ }
+
+ gfig_paint (selvals.brshtype, gfig_context->drawable_id, i, line_pnts);
+ }
+}
+
+static GfigObject *
+d_copy_circle (GfigObject * obj)
+{
+ GfigObject *nc;
+
+ g_assert (obj->type == CIRCLE);
+
+ nc = d_new_object (CIRCLE, obj->points->pnt.x, obj->points->pnt.y);
+ nc->points->next = d_copy_dobjpoints (obj->points->next);
+
+ return nc;
+}
+
+void
+d_circle_object_class_init (void)
+{
+ GfigObjectClass *class = &dobj_class[CIRCLE];
+
+ class->type = CIRCLE;
+ class->name = "CIRCLE";
+ class->drawfunc = d_draw_circle;
+ class->paintfunc = d_paint_circle;
+ class->copyfunc = d_copy_circle;
+ class->update = d_update_circle;
+}
+
+static void
+d_update_circle (GdkPoint *pnt)
+{
+ DobjPoints *center_pnt, *edge_pnt;
+
+ center_pnt = obj_creating->points;
+
+ if (!center_pnt)
+ return; /* No points */
+
+ if ((edge_pnt = center_pnt->next))
+ {
+ edge_pnt->pnt = *pnt;
+ }
+ else
+ {
+ edge_pnt = new_dobjpoint (pnt->x, pnt->y);
+ center_pnt->next = edge_pnt;
+ }
+}
+
+void
+d_circle_start (GdkPoint *pnt,
+ gboolean shift_down)
+{
+ obj_creating = d_new_object (CIRCLE, pnt->x, pnt->y);
+}
+
+void
+d_circle_end (GdkPoint *pnt,
+ gboolean shift_down)
+{
+ /* Under control point */
+ if (!obj_creating->points->next)
+ {
+ /* No circle created */
+ free_one_obj (obj_creating);
+ }
+ else
+ {
+ add_to_all_obj (gfig_context->current_obj, obj_creating);
+ }
+
+ obj_creating = NULL;
+}
+