mirror of https://github.com/CGAL/cgal
Improve documentation
This commit is contained in:
Andreas Fabri
parent
ff368dd84f
commit
85bb0775e8
|
|
@ -536,11 +536,11 @@ package \refPkgSurfaceMeshSimplification, in order to simplify respecting a tole
|
|||
\subsubsection InsideExample Polyhedral Envelope Example
|
||||
\cgalExample{Polygon_mesh_processing/polyhedral_envelope.cpp}
|
||||
|
||||
The algorithm is described in \cgalCite{cgal:wshap-eepec-20} and can be summarized as follows.
|
||||
First for each triangle a <em>prism</em> is constructed with an offset of \f$ \epsilon/\sqrt(3) \f$,
|
||||
The algorithm is described in \cgalCite{cgal:Wwshap-eepec-20} and can be summarized as follows.
|
||||
First for each triangle a <em>prism</em> is constructed with an offset of \f$ \epsilon/\sqrt(3) \f$ where \f$ \epsilon\f$ is the tolerance,
|
||||
and all prisms are stored in an AABB tree. For a query point the algorithm checks if is inside a prism.
|
||||
For a query segment or triangle the algorithms checks if the query is completely covered.
|
||||
The details of how to check the covering can be found in the paper of Wang et al. \cgalCite{cgal:Wwshap-eepec-20}
|
||||
The details of how to check this covering can be found in the paper of Wang et al.
|
||||
|
||||
\subsection PMPShapePredicates Shape Predicates
|
||||
|
||||
|
|
|
|||
|
|
@ -87,7 +87,7 @@ namespace CGAL {
|
|||
/**
|
||||
* \ingroup PkgPolygonMeshProcessingRef
|
||||
* This class provides a test whether a query point, segment, or triangle
|
||||
* is inside or outside a polyhedral envelope of a triangle soup.
|
||||
* is inside or outside a polyhedral envelope of a triangle mesh.
|
||||
*
|
||||
* @tparam GeomTraits a geometric traits class, model of `Kernel`
|
||||
*/
|
||||
|
|
@ -1815,7 +1815,7 @@ private:
|
|||
public:
|
||||
|
||||
/*!
|
||||
* \returns `true` if the query point is inside the polygonal envelope.
|
||||
* \returns `true`, iff the query point is inside the polygonal envelope.
|
||||
*/
|
||||
|
||||
bool
|
||||
|
|
@ -1835,7 +1835,7 @@ public:
|
|||
|
||||
|
||||
/*!
|
||||
* \returns `true` if the query segment is inside the polygonal envelope.
|
||||
* \returns `true`, iff the query segment defined by the points `source` and `target` is inside the polygonal envelope.
|
||||
*/
|
||||
bool
|
||||
operator()(const Point_3& source, const Point_3& target) const
|
||||
|
|
@ -1855,7 +1855,7 @@ public:
|
|||
|
||||
|
||||
/*!
|
||||
* \returns `true` if the query triangle is inside the envelope.
|
||||
* \returns `true`, iff the query triangle formed by the points `t0`, `t1`, and `t2` is inside the envelope.
|
||||
*/
|
||||
bool
|
||||
operator()(const Point_3& t0, const Point_3& t1, const Point_3& t2) const
|
||||
|
|
|
|||
|
|
@ -18,7 +18,7 @@ not filter any placement.
|
|||
\sa `Envelope`
|
||||
|
||||
*/
|
||||
template <typename GeomTraits,typename GetFilter_>
|
||||
template <typename GeomTraits, typename GetFilter_>
|
||||
class Envelope_filter {
|
||||
public:
|
||||
|
||||
|
|
|
|||
|
|
@ -22,7 +22,7 @@ class GetCost
|
|||
{
|
||||
public:
|
||||
|
||||
/// The class Edge_profile regroups useful information about an edge, such as its incident vertices and faces.
|
||||
/// The class `Edge_profile` regroups useful information about an edge, such as its incident vertices and faces.
|
||||
typedef CGAL::Surface_mesh_simplification::Edge_profile Edge_profile;
|
||||
|
||||
/// \name Operations
|
||||
|
|
@ -38,4 +38,3 @@ public:
|
|||
/// @}
|
||||
|
||||
}; /* end GetCost */
|
||||
|
||||
|
|
|
|||
|
|
@ -3,7 +3,10 @@
|
|||
\cgalConcept
|
||||
|
||||
The concept `GetFilter` describes the requirements for the <I>policy
|
||||
function object</I> which gets the profile and placement of an edge.
|
||||
function object</I> which gets the profile and placement of an edge
|
||||
and which can filter the placement. The filtering is only done when
|
||||
an edge is taken from the priority queue in order to get collapsed,
|
||||
and neither when the edge is inserted or updated in the priority queue.
|
||||
|
||||
The placement returned is a `boost::optional` value (i.e., it can
|
||||
be absent). The value `boost::none` indicates that the edge should not be collapsed.
|
||||
|
|
@ -11,8 +14,8 @@ be absent). The value `boost::none` indicates that the edge should not be collap
|
|||
\cgalRefines `DefaultConstructible`
|
||||
\cgalRefines `CopyConstructible`
|
||||
|
||||
\cgalHasModel `CGAL::Surface_mesh_simplification::Bounded_normal_change_filter<Placement>`
|
||||
\cgalHasModel `CGAL::Surface_mesh_simplification::FastEnvelopeFilter<GeomTraits,Placement>`
|
||||
\cgalHasModel `CGAL::Surface_mesh_simplification::Bounded_normal_change_filter<BaseFilter>`
|
||||
\cgalHasModel `CGAL::Surface_mesh_simplification::Envelope_filter<GeomTraits, BaseFilter>`
|
||||
*/
|
||||
|
||||
|
||||
|
|
@ -20,7 +23,7 @@ class GetFilter
|
|||
{
|
||||
public:
|
||||
|
||||
/// The class Edge_profile regroups useful information about an edge, such as its incident vertices and faces.
|
||||
/// The class `Edge_profile` regroups useful information about an edge, such as its incident vertices and faces.
|
||||
typedef CGAL::Surface_mesh_simplification::Edge_profile Edge_profile;
|
||||
|
||||
/// \name Operations
|
||||
|
|
|
|||
|
|
@ -27,7 +27,7 @@ class GetPlacement
|
|||
{
|
||||
public:
|
||||
|
||||
/// The class Edge_profile regroups useful information about an edge, such as its incident vertices and faces.
|
||||
/// The class `Edge_profile` regroups useful information about an edge, such as its incident vertices and faces.
|
||||
typedef CGAL::Surface_mesh_simplification::Edge_profile Edge_profile;
|
||||
|
||||
/// \name Operations
|
||||
|
|
|
|||
|
|
@ -185,8 +185,8 @@ the mesh as much as possible.
|
|||
|
||||
\subsection Surface_mesh_simplificationCostStrategyPolicies Cost Strategy Policies
|
||||
|
||||
The cost strategy used by the algorithm is selected by means of two policies:
|
||||
`GetPlacement` and `GetCost`.
|
||||
The cost strategy used by the algorithm is selected by means of three policies:
|
||||
`GetPlacement`, `GetCost`, and `GetFilter`.
|
||||
|
||||
The `GetPlacement` policy is called to compute the new position
|
||||
for the remaining vertex after the halfedge-collapse. It returns
|
||||
|
|
@ -209,7 +209,7 @@ But this is a trade-off: the cost of a collapse is a function of the placement
|
|||
(the new position chosen for the remaining vertex) so before `GetCost`
|
||||
is called for each and every edge, `GetPlacement` must also be called to obtain
|
||||
the placement parameter to the cost function.
|
||||
But that placement, which is a 3D Point, is not attached to each and every edge since
|
||||
But that placement, which is a 3D point, is not attached to each and every edge since
|
||||
that would easily <I>triple</I> the additional storage requirement.
|
||||
On the one hand, this dramatically saves on memory but on the other hand is
|
||||
a processing waste because when an edge is effectively collapsed, `GetPlacement`
|
||||
|
|
@ -223,6 +223,17 @@ must be called several times just as well. Caching the placement can only avoid
|
|||
very last call, when the edge is collapsed, but not all the previous calls which
|
||||
are needed because the placement (and cost) changes.
|
||||
|
||||
We have not yet explained what the `GetFilter` policy is about.
|
||||
While the cost is a scalar that is used in the priority queue, there may be
|
||||
additional criteria coming in to decide if the edge collapse shall be performed or not.
|
||||
While such a criterion could be easily integrated into the cost function,
|
||||
that is setting the cost to infinity in order not to be considered a candidate for a collapse,
|
||||
we test the criterion only for an edge when it is the next edge to collapse.
|
||||
This makes the mesh simplification faster in case the computation of the
|
||||
criterion is expensive, for example when we check if the simplified mesh
|
||||
is in a tolerance envelope of the input mesh.
|
||||
|
||||
|
||||
\section Surface_mesh_simplificationAPI API
|
||||
|
||||
\subsection Surface_mesh_simplificationAPIOverview API Overview
|
||||
|
|
@ -343,7 +354,7 @@ rejects this placement by returning `boost::none`.
|
|||
|
||||
\note This filter class replaces the usage of the class `Surface_mesh_simplification::Bounded_normal_change_placement`.
|
||||
Using the filter is faster as it is only performed on the edge to be collapsed next,
|
||||
and not during the update on all edges incident to the vertex that is the result of the edhe collapse.
|
||||
and not during the update of all edges incident to the vertex that is the result of the edge collapse.
|
||||
|
||||
\cgalExample{Surface_mesh_simplification/edge_collapse_bounded_normal_change.cpp}
|
||||
|
||||
|
|
|
|||
Loading…
Reference in New Issue