//----------------------------------------------------------------//
ZLVec2D USSurface2D::GetNorm ( const ZLVec2D& e0, const ZLVec2D& e1 ) {
ZLVec2D norm;
norm = e0;
norm.Sub ( e1 );
norm.Rotate90Anticlockwise ();
norm.Norm ();
return norm;
}
//----------------------------------------------------------------//
bool USSurface2D::GetHit ( ZLVec2D& sphereLoc, ZLVec2D& move, SurfaceHit2D& hit ) {
// The usual stuff...
ZLVec2D unitMove = move;
unitMove.Norm ();
if ( unitMove.Dot ( this->mNorm ) >= -0.001f ) return false;
if ( ZLDist::PointToPlane2D ( sphereLoc, *this ) <= 0.0f ) return false;
// Get the point of first contact on the polygon...
ZLVec2D pofcop = this->mNorm;
pofcop.Reverse ();
pofcop.Add ( sphereLoc );
this->ClampPoint ( pofcop );
// Send a ray from the point on the surface to intersect the circle.
// The ray is the inverse of the move vec.
ZLVec2D inverseMove = move;
inverseMove.Reverse ();
float t0, t1;
u32 sectType;
sectType = ZLSect::VecToCircle ( t0, t1, pofcop, inverseMove, sphereLoc, 1.0f );
// Bail if the point will not intersect the sphere.
if ( sectType == ZLSect::SECT_PARALLEL ) return false;
if ( t0 >= hit.mTime ) return false;
// Bail if the point will graze the sphere.
if ( sectType == ZLSect::SECT_TANGENT ) return false;
// Bail if the point will stay outside of the sphere.
if (( t0 > 1.0f ) || ( t1 < 0.0f )) return false;
// OMG! We hit something!
float time = t0;
hit.mTime = time;
inverseMove.Scale ( t0 );
hit.mPoint = pofcop;
hit.mPoint.Add ( inverseMove );
hit.mNorm = sphereLoc;
hit.mNorm.Sub ( hit.mPoint );
hit.mNorm.Norm ();
if ( unitMove.Dot ( hit.mNorm ) >= -0.001f ) return false;
return true;
}
//----------------------------------------------------------------//
void MOAIVectorUtil::ComputeLineJoins ( MOAIVectorLineJoin* joins, const ZLVec2D* verts, int nVerts, bool open, bool forward, bool interior ) {
int top = nVerts - 1;
float scale = interior ? -1.0f : 1.0f;
if ( forward ) {
for ( int i = 0; i < nVerts; ++i ) {
joins [ i ].mVertex = verts [ i ];
}
}
else {
for ( int i = 0; i < nVerts; ++i ) {
joins [ i ].mVertex = verts [ top - i ];
}
}
for ( int i = 0; i < nVerts; ++i ) {
ZLVec2D v0 = joins [ i ].mVertex;
ZLVec2D v1 = joins [( i + 1 ) % nVerts ].mVertex;
ZLVec2D n = v1;
n.Sub ( v0 );
n.Norm ();
joins [ i ].mEdgeVec = n;
n.Rotate90Anticlockwise ();
n.Scale ( scale );
joins [ i ].mEdgeNorm = n;
joins [ i ].mIsCap = false;
}
int start = 0;
int max = nVerts;
if ( open ) {
joins [ 0 ].mIsCap = true;
joins [ 0 ].mJointNorm = joins [ 0 ].mEdgeNorm;
joins [ top ].mIsCap = true;
joins [ top ].mEdgeVec = joins [ top - 1 ].mEdgeVec;
joins [ top ].mEdgeNorm = joins [ top - 1 ].mEdgeNorm;
joins [ top ].mJointNorm = joins [ top ].mEdgeNorm;
start = 1;
max = top;
}
for ( int i = start; i < max; ++i ) {
ZLVec2D n = joins [( i + top ) % nVerts ].mEdgeNorm;
n.Add ( joins [ i ].mEdgeNorm );
n.Norm ();
joins [ i ].mJointNorm = n;
}
}