/*
* Copyright (c) 2011 Hypertriton, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
* USE OF THIS SOFTWARE EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Construction geometry: Polygon.
*/
#include
#include
#include
#include
#define SG_POLYGON_PRECISION 0.2 /* For plane intersection test */
SG_Polygon *
SG_PolygonNew(void *parent, const char *name, const M_Polygon *mp)
{
SG_Polygon *poly;
poly = Malloc(sizeof(SG_Polygon));
AG_ObjectInitNamed(poly, &sgPolygonClass, name);
AG_ObjectAttach(parent, poly);
if (mp != NULL) {
M_PolygonCopy(&poly->P, mp);
}
return (poly);
}
static void
Init(void *_Nonnull obj)
{
SG_Polygon *poly = obj;
M_PolygonInit(&poly->P);
}
static int
Load(void *_Nonnull obj, AG_DataSource *_Nonnull ds, const AG_Version *_Nonnull ver)
{
SG_Polygon *poly = obj;
poly->P = M_PolygonRead(ds);
return (0);
}
static int
Save(void *_Nonnull obj, AG_DataSource *_Nonnull ds)
{
SG_Polygon *poly = obj;
M_PolygonWrite(ds, &poly->P);
return (0);
}
static void
Draw(void *_Nonnull obj, SG_View *_Nonnull view)
{
SG_Polygon *poly = obj;
SG_Geom *geom = SGGEOM(poly);
Uint i;
SG_GeomDrawBegin(geom);
GL_Begin(GL_LINE_LOOP);
if (SGNODE(geom)->flags & SG_NODE_SELECTED) {
GL_Color3ub(0, 255, 0);
} else {
GL_Color4v(&geom->c);
}
for (i = 0; i < poly->P.n; i++) {
GL_Vertex2v(&poly->P.v[i]);
}
GL_End();
SG_GeomDrawEnd(geom);
}
static int
Intersect(void *_Nonnull obj, M_Geom3 g, M_GeomSet3 *_Nullable S)
{
SG_Polygon *poly = obj;
M_Geom3 xg;
switch (g.type) {
case M_LINE:
{
M_Vector3 p1, p2, u;
M_Real d, n, Si;
M_Vector3 xp;
M_LineToPts3(g.g.line, &p1, &p2);
u = M_VecSub3(p2, p1);
d = M_VecDot3(M_VecK3(), u);
n = -M_VecDot3(M_VecK3(), p1);
if (Fabs(d) < SG_POLYGON_PRECISION) {
if (n < SG_POLYGON_PRECISION) {
if (S != NULL) {
xg.type = M_LINE;
xg.g.line = g.g.line;
M_GeomSetAdd3(S, &xg);
}
return (1);
} else {
return (0);
}
}
Si = n/d;
if (Si < 0.0 || Si > 1.0)
return (0);
xp = M_VecAdd3(g.g.line.p, M_VecScale3p(&u,Si));
if (M_PointInPolygon(&poly->P, M_VECTOR2(xp.x,xp.y))) {
if (S != NULL) {
xg.type = M_POINT;
xg.g.point = xp;
M_GeomSetAdd3(S, &xg);
}
return (1);
} else {
return (0);
}
}
break;
default:
return (-1);
}
return (0);
}
SG_NodeClass sgPolygonClass = {
{
"SG_Node:SG_Geom:SG_Polygon",
sizeof(SG_Polygon),
{ 0,0 },
Init,
NULL, /* free */
NULL, /* destroy */
Load,
Save,
SG_NodeEdit
},
NULL, /* menuInstance */
NULL, /* menuClass */
Draw,
Intersect,
NULL /* edit */
};