gimp/plug-ins/gfig/gfig-circle.c

236 lines
5.8 KiB
C

/*
* 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,
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);
}
/* 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, 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 (GimpGfig *gfig,
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, gfig_context->current_obj, obj_creating);
}
obj_creating = NULL;
}