/*
=============
idWinding2D::PlaneDistance
=============
*/
float idWinding2D::PlaneDistance( const idVec3 &plane ) const {
int i;
float d, min, max;
min = idMath::INFINITY;
max = -min;
for ( i = 0; i < numPoints; i++ ) {
d = plane.x * p[i].x + plane.y * p[i].y + plane.z;
if ( d < min ) {
min = d;
if ( IEEE_FLT_SIGNBITSET( min ) & IEEE_FLT_SIGNBITNOTSET( max ) ) {
return 0.0f;
}
}
if ( d > max ) {
max = d;
if ( IEEE_FLT_SIGNBITSET( min ) & IEEE_FLT_SIGNBITNOTSET( max ) ) {
return 0.0f;
}
}
}
if ( IEEE_FLT_SIGNBITNOTSET( min ) ) {
return min;
}
if ( IEEE_FLT_SIGNBITSET( max ) ) {
return max;
}
return 0.0f;
}
/*
============
idBox::GetProjectionSilhouetteVerts
============
*/
int idBox::GetProjectionSilhouetteVerts( const idVec3& projectionOrigin, idVec3 silVerts[6] ) const
{
float f;
int i, planeBits, *index;
idVec3 points[8], dir1, dir2;
ToPoints( points );
dir1 = points[0] - projectionOrigin;
dir2 = points[6] - projectionOrigin;
f = dir1 * axis[0];
planeBits = IEEE_FLT_SIGNBITNOTSET( f );
f = dir2 * axis[0];
planeBits |= IEEE_FLT_SIGNBITSET( f ) << 1;
f = dir1 * axis[1];
planeBits |= IEEE_FLT_SIGNBITNOTSET( f ) << 2;
f = dir2 * axis[1];
planeBits |= IEEE_FLT_SIGNBITSET( f ) << 3;
f = dir1 * axis[2];
planeBits |= IEEE_FLT_SIGNBITNOTSET( f ) << 4;
f = dir2 * axis[2];
planeBits |= IEEE_FLT_SIGNBITSET( f ) << 5;
index = boxPlaneBitsSilVerts[planeBits];
for( i = 0; i < index[0]; i++ )
{
silVerts[i] = points[index[i + 1]];
}
return index[0];
}
/*
============
idWinding2D::LineIntersection
============
*/
bool idWinding2D::LineIntersection( const idVec2 &start, const idVec2 &end ) const {
int i, numEdges;
int sides[MAX_POINTS_ON_WINDING_2D+1], counts[3];
float d1, d2, epsilon = 0.1f;
idVec3 plane, edges[2];
counts[SIDE_FRONT] = counts[SIDE_BACK] = counts[SIDE_ON] = 0;
plane = Plane2DFromPoints( start, end );
for ( i = 0; i < numPoints; i++ ) {
d1 = plane.x * p[i].x + plane.y * p[i].y + plane.z;
if ( d1 > epsilon ) {
sides[i] = SIDE_FRONT;
}
else if ( d1 < -epsilon ) {
sides[i] = SIDE_BACK;
}
else {
sides[i] = SIDE_ON;
}
counts[sides[i]]++;
}
sides[i] = sides[0];
if ( !counts[SIDE_FRONT] ) {
return false;
}
if ( !counts[SIDE_BACK] ) {
return false;
}
numEdges = 0;
for ( i = 0; i < numPoints; i++ ) {
if ( sides[i] != sides[i+1] && sides[i+1] != SIDE_ON ) {
edges[numEdges++] = Plane2DFromPoints( p[i], p[(i+1)%numPoints] );
if ( numEdges >= 2 ) {
break;
}
}
}
if ( numEdges < 2 ) {
return false;
}
d1 = edges[0].x * start.x + edges[0].y * start.y + edges[0].z;
d2 = edges[0].x * end.x + edges[0].y * end.y + edges[0].z;
if ( IEEE_FLT_SIGNBITNOTSET( d1 ) & IEEE_FLT_SIGNBITNOTSET( d2 ) ) {
return false;
}
d1 = edges[1].x * start.x + edges[1].y * start.y + edges[1].z;
d2 = edges[1].x * end.x + edges[1].y * end.y + edges[1].z;
if ( IEEE_FLT_SIGNBITNOTSET( d1 ) & IEEE_FLT_SIGNBITNOTSET( d2 ) ) {
return false;
}
return true;
}
