ON_SIL_EVENT Class Reference

#include <opennurbs_plus_sil.h>

Public Types
enum	END_TYPE : unsigned int {   kEndUnknown = 0, kEndBoundary = 1, kEndEdge = 2, kEndLoop = 3,   kEndCusp = 4, kEndProjected = 5, kEndSection = 6, kEndSngularity = 7 }
enum	SIDE_FILL : unsigned int { kSideUnset = 0, kSideSurface = 1, kSideVoid = 2, kSideOtherSurface = 3 }
enum	TYPE : unsigned int {   kNoSilEvent = 0, kSilProjecting = 1, kSilTanProject = 2, kSilTangent = 4,   kSilCrease = 8, kSilBoundary = 16, kNonSilCrease = 256, kNonSilTangent = 512,   kNonSilSeam = 1024, kSectionCut = 4096, kMiscFeature = 8192, kDraftCurve = 32768 }

Public Member Functions
enum TYPE unsigned int enum END_TYPE unsigned int	ON_SIL_EVENT () ON_NOEXCEPT
	ON_SIL_EVENT (const ON_SIL_EVENT &rhs)
	ON_SIL_EVENT (TYPE ttype, ON_COMPONENT_INDEX cci, END_TYPE etype0, ON_COMPONENT_INDEX eci0, double p0, END_TYPE etype1, ON_COMPONENT_INDEX eci1, double p1, ON_Curve *c3d=nullptr, ON_Curve *c2d=nullptr) ON_NOEXCEPT
	~ON_SIL_EVENT ()
void	Dump (ON_TextLog &text_log) const
bool	IsSilhouetteType () const
bool	IsTangentSilhouetteType () const
ON_SIL_EVENT &	operator= (const ON_SIL_EVENT &rhs)

Static Public Member Functions
static bool	IsSilhouetteType (TYPE)
static bool	IsTangentSilhouetteType (TYPE)
	returns true for kSilProjecting through kSilTangent More...

Public Attributes
ON_COMPONENT_INDEX	m_ci
ON_Curve *	m_curve2d
	parameter space curve if available or nullptr More...
ON_Curve *	m_curve3d
	These are deleted by ~ON_SIL_EVENT() More...
ON_COMPONENT_INDEX	m_end_ci [2]
double	m_end_parameter [2]
END_TYPE	m_end_type [2]
SIDE_FILL	m_side_fill [2]
TYPE	m_type

Detailed Description

The ON_SIL_EVENT class is used to report silhouettes from functions such as ON_Brep::GetSilhouette(..)

Member Enumeration Documentation

END_TYPE

enum ON_SIL_EVENT::END_TYPE : unsigned int

END_TYPE describes the endpoint of an ON_SIL_EVENT

Enumerator
kEndUnknown
kEndBoundary	end is on geometry boundary
kEndEdge	end at a brep edge
kEndLoop	TODO?? ( why this and kEndProjected ) end in on a projecting region loop.
kEndCusp	This end is a silhouette cusp point. (i.e. The projected silhouette has a kink)
kEndProjected	ends on a projected region loop
kEndSection	ends at a section cut
kEndSngularity	ends at a point where more than two ON_SIL_EVENTs may join together.

SIDE_FILL

enum ON_SIL_EVENT::SIDE_FILL : unsigned int

When a silhouette is projected on the image plane ( determined by the camera location or direction), and projects to a curve (not a point), the image area to the left or right of a projected silhouette curve is filled with either the surface or a void.

Enumerator
kSideUnset
kSideSurface
kSideVoid
kSideOtherSurface	Not used for silhouette results but for ....

TYPE

enum ON_SIL_EVENT::TYPE : unsigned int

Description: The types are ordered. The type of a ON_SIL_EVENT is reported as the lowest valued type that applies. For example, a boundary that is a tangent silhouette will be reported as kSilTangent type not a kSilBoundary.

Enumerator
kNoSilEvent
kSilProjecting	boundary of a region that projects to a curve.
kSilTanProject	The view direction is tangent to the surface over the entire region. tangent silhouette curve where the curve projects to a point( within tolerance)
kSilTangent	in this case side_fill[i] is meaningless so it's left unset. tangent silhouette curve.
kSilCrease	The view direction is tangent to the surface along the curve. crease on geometry that is a silhouette
kSilBoundary	boundary of geometry is always a silhouette
kNonSilCrease	non_sil_features A geometry crease that is not a silhouette
kNonSilTangent	A tangent edge that is not a silhouette.
kNonSilSeam	A surface seam that is not a silhouette.
kSectionCut	Intersection with a clipping plane, not produced by GetSilhouette(...) functions.
kMiscFeature	Miscellaneous curve feature, used for curve objects in TL_HiddenLineDrawing.
kDraftCurve	draft curve is a curve of constant draft angle. Draft curves are produced when SetDraftCurve(..) is called on the ON_SilhouetteParameter.

Constructor & Destructor Documentation

ON_SIL_EVENT() [1/3]

enum TYPE unsigned int enum END_TYPE unsigned int ON_SIL_EVENT::ON_SIL_EVENT

(

)

ON_SIL_EVENT() [2/3]

ON_SIL_EVENT::ON_SIL_EVENT	(	TYPE	ttype,
		ON_COMPONENT_INDEX	cci,
		END_TYPE	etype0,
		ON_COMPONENT_INDEX	eci0,
		double	p0,
		END_TYPE	etype1,
		ON_COMPONENT_INDEX	eci1,
		double	p1,
		ON_Curve *	c3d = nullptr,
		ON_Curve *	c2d = nullptr
	)

This constructor leaves m_side_fill[i]=unset but initializes all other fields. The lifetimes of c3d and/or c2d are managed by the ON_SIL_EVENT class.

ON_SIL_EVENT() [3/3]

ON_SIL_EVENT::ON_SIL_EVENT

(

const ON_SIL_EVENT &

rhs

)

An ON_SIL_EVENT can own a pair of ON_Curves pointed to by m_curve2d and m_curve3d. So the copy constructor and operator= makes copies of these curves. And destructor ~ON_SIL_EVENT() deletes these curves.

~ON_SIL_EVENT()

ON_SIL_EVENT::~ON_SIL_EVENT

(

)

Member Function Documentation

Dump()

void ON_SIL_EVENT::Dump

(

ON_TextLog &

text_log

)

const

IsSilhouetteType() [1/2]

bool ON_SIL_EVENT::IsSilhouetteType

(

)

const

IsSilhouetteType() [2/2]

static bool ON_SIL_EVENT::IsSilhouetteType ( TYPE  )

static

IsSilhouetteType() returns true for types kSilProjecting through kSilBoundary.

IsTangentSilhouetteType() [1/2]

bool ON_SIL_EVENT::IsTangentSilhouetteType

(

)

const

IsTangentSilhouetteType() [2/2]

static bool ON_SIL_EVENT::IsTangentSilhouetteType ( TYPE  )

static

returns true for kSilProjecting through kSilTangent

IsTangentSilhouetteType() returns true for types kSilProjecting through kSilTangent.

operator=()

ON_SIL_EVENT& ON_SIL_EVENT::operator=

(

const ON_SIL_EVENT &

rhs

)

Member Data Documentation

m_ci

ON_COMPONENT_INDEX ON_SIL_EVENT::m_ci

m_ci if valid, is the component index of geometry containing entire silhouette curve. A typical example is ON_SIL_EVENT that starts and ends on ON_BrepEdges and goes across the interior of face. In this case m_ci will be the component index of the face, m_end_ci[0] and m_end_ci[1] will be the component indices of the edges on which the ON_SIL_EVENT terminates, m_end_type[0] and m_end_type[1] will be either END_TYPE::kEndBoundary or END_TYPE::kEndEdge.

m_curve2d

ON_Curve* ON_SIL_EVENT::m_curve2d

parameter space curve if available or nullptr

m_curve3d

ON_Curve* ON_SIL_EVENT::m_curve3d

These are deleted by ~ON_SIL_EVENT()

m_end_ci

ON_COMPONENT_INDEX ON_SIL_EVENT::m_end_ci[2]

m_end_ci[0], if valid, is the component index of geometry containing the ON_SIL_EVENT start point. Similarly m_end_ci[0] applies to the ON_SIL_EVENT end point.

m_end_parameter

double ON_SIL_EVENT::m_end_parameter[2]

m_end_parameter[0] is the ON_Brep::Edge parameter of the ON_SIL_EVENT start point when m_end_type[0] = END_TYPE::kEndBoundary, or m_end_type[0] = END_TYPE::kEndEdge. m_end_parameter[0] similarly applies to the end point.

m_end_type

END_TYPE ON_SIL_EVENT::m_end_type[2]

m_end_type[0] is the END_TYPE of the curve start and and m_end_type[1] is the END_TYPE of the curve end.

m_side_fill

SIDE_FILL ON_SIL_EVENT::m_side_fill[2]

m_side_fill[0] defines how the region in the image plane to the left (or right for m_side_fill[1]) of the projected silhouette curve is filled.

Example: generally the surface locally lies to either the left or the right of the projected silhouette curve in the image plane. The basic degenerate cases are that of a projecting surface or the case of a silhouette with the surface on both sides of the silhouette locally m_side_fill[0] m_side_fill[1] Left Side side_surface side_void Right side_void side_surface

projecting side_void side_void degenerate side_surface side_surface

m_type

TYPE ON_SIL_EVENT::m_type