void draw_segments( const viewDef_t *viewDef, const MySegments & s, idVec4 color )
{
for(unsigned int i = 0; i < s.size(); i+=2)
{
viewDef->renderWorld->DebugLine( color, v4to3(s[i]), v4to3(s[i+1]));
}
}
// clip the segments of e by the planes of polyhedron a.
void clip_segments(const polyhedron &ph, MySegments &is, MySegments &os)
{
const MyArrayPoly &p = ph.p;
for (unsigned int i = 0; i < is.size(); i+=2) {
idVec4 a = is[i ];
idVec4 b = is[i+1];
idVec4 c;
bool discard = false;
for (unsigned int j = 0; j < p.size(); j++) {
float da = a * p[j].plane;
float db = b * p[j].plane;
float rdw = 1/(da - db);
int code = 0;
if (da > 0)
code = 2;
if (db > 0)
code |= 1;
switch (code) {
case 3:
discard = true;
break;
case 2:
c = -db * rdw * a + da * rdw * b;
a = c;
break;
case 1:
c = -db * rdw * a + da * rdw * b;
b = c;
break;
case 0:
break;
default:
common->Printf("bad clip code!\n");
break;
}
if (discard)
break;
}
if (! discard) {
os.push_back(a);
os.push_back(b);
}
}
}
