bool ON_Mesh::EvaluatePoint( const class ON_ObjRef& objref, ON_3dPoint& P ) const
{
// virtual function default
P = ON_UNSET_POINT;
ON_COMPONENT_INDEX ci = objref.m_component_index;
switch ( ci.m_type )
{
case ON_COMPONENT_INDEX::mesh_vertex:
if ( ci.m_index >= 0 && ci.m_index < m_V.Count() )
P = m_V[ci.m_index];
break;
case ON_COMPONENT_INDEX::meshtop_vertex:
if ( ci.m_index >= 0 && ci.m_index < m_top.m_topv.Count() )
{
const ON_MeshTopologyVertex& topv = m_top.m_topv[ci.m_index];
if ( topv.m_v_count > 0 && topv.m_vi )
{
int vi = topv.m_vi[0];
if ( vi >= 0 && vi < m_V.Count() )
P = m_V[vi];
}
}
break;
case ON_COMPONENT_INDEX::meshtop_edge:
if ( 5 == objref.m_evp.m_t_type
&& fabs(objref.m_evp.m_t[0] + objref.m_evp.m_t[1] - 1.0) <= ON_SQRT_EPSILON )
{
ON_Line L = m_top.TopEdgeLine(ci.m_index);
if ( L.IsValid() )
{
P = L.PointAt(objref.m_evp.m_t[0]);
}
}
break;
case ON_COMPONENT_INDEX::mesh_face:
if ( 4 == objref.m_evp.m_t_type
&& fabs(objref.m_evp.m_t[0] + objref.m_evp.m_t[1] + objref.m_evp.m_t[2] + objref.m_evp.m_t[3] - 1.0) <= ON_SQRT_EPSILON )
{
if ( ci.m_index >= 0 && ci.m_index < m_F.Count() )
{
const int* fvi = m_F[ci.m_index].vi;
if ( fvi[0] < 0 || fvi[0] >= m_V.Count() )
break;
if ( fvi[1] < 0 || fvi[1] >= m_V.Count() )
break;
if ( fvi[2] < 0 || fvi[2] >= m_V.Count() )
break;
if ( fvi[3] < 0 || fvi[3] >= m_V.Count() )
break;
ON_3dPoint V[4];
V[0] = m_V[fvi[0]];
V[1] = m_V[fvi[1]];
V[2] = m_V[fvi[2]];
V[3] = m_V[fvi[3]];
P = objref.m_evp.m_t[0]*V[0] + objref.m_evp.m_t[1]*V[1] + objref.m_evp.m_t[2]*V[2] + objref.m_evp.m_t[3]*V[3];
}
}
break;
default:
// intentionally skipping other ON_COMPONENT_INDEX::TYPE enum values
break;
}
return P.IsValid();
}
int ON_ArePointsOnLine( // returns 0=no, 1 = yes, 2 = pointset is (to tolerance) a single point on the line
int dim, // 2 or 3
int is_rat,
int count,
int stride, const double* point,
const ON_BoundingBox& bbox, // if needed, use ON_GetBoundingBox(dim,is_rat,count,stride,point)
const ON_Line& line, // line to test
double tolerance
)
{
double w;
int i, j, k;
if ( count < 1 )
return 0;
if ( !line.IsValid() )
{
ON_ERROR("line parameter not valid");
return 0;
}
if ( !bbox.IsValid() )
{
ON_ERROR("bbox parameter not valid");
return 0;
}
if ( !ON_IsValid(tolerance) || tolerance < 0.0 )
{
ON_ERROR("tolerance parameter not valid");
return 0;
}
if ( dim < 2 || dim > 3 )
{
ON_ERROR("dim parameter not valid");
return 0;
}
if ( 0 == point )
{
ON_ERROR("point parameter not valid");
return 0;
}
if ( stride < (is_rat?(dim+1):dim) )
{
ON_ERROR("stride parameter not valid");
return 0;
}
int rc = 0;
if ( tolerance == 0.0 ) {
tolerance = bbox.Tolerance();
}
ON_3dPoint Q;
// test bounding box to quickly detect the common coordinate axis cases
rc = (count == 1 || bbox.Diagonal().Length() <= tolerance) ? 2 : 1;
for ( i = 0; rc && i < 2; i++ ) {
Q.x = bbox[i].x;
for ( j = 0; rc && j < 2; j++) {
Q.y = bbox[j].y;
for ( k = 0; rc && k < 2; k++) {
Q.z = bbox[k].z;
if ( Q.DistanceTo( line.ClosestPointTo( Q ) ) > tolerance )
rc = 0;
}
}
}
if ( !rc ) {
// test points one by one
Q.Zero();
rc = (count == 1 || bbox.Diagonal().Length() <= tolerance) ? 2 : 1;
if ( is_rat ) {
for ( i = 0; i < count; i++ ) {
w = point[dim];
if ( w == 0.0 ) {
ON_ERROR("rational point has zero weight");
return 0;
}
ON_ArrayScale( dim, 1.0/w, point, &Q.x );
if ( Q.DistanceTo( line.ClosestPointTo( Q ) ) > tolerance ) {
rc = 0;
break;
}
point += stride;
}
}
else {
for ( i = 0; i < count; i++ ) {
memcpy( &Q.x, point, dim*sizeof(Q.x) );
if ( Q.DistanceTo( line.ClosestPointTo( Q ) ) > tolerance ) {
rc = 0;
break;
}
point += stride;
}
}
}
return rc;
}