#include <cartotype_path.h>
Public Member Functions | |
| virtual size_t | Points () const =0 |
| virtual OutlinePoint | Point (size_t aIndex) const =0 |
| virtual bool | Closed () const =0 |
| operator ContourView () const | |
| size_t | Contours () const |
| OutlinePoint | LastPoint () const |
| OutlinePoint | FractionalPoint (double aIndex) const |
| bool | IsGridOrientedRectangle (Rect *aRect=nullptr) const |
| bool | Anticlockwise () const |
| PolygonOrientation | Orientation () const |
| bool | Contains (double aX, double aY) const |
| bool | Contains (const CartoTypeCore::Point &aPoint) const |
| Outline | ClippedContour (const Rect &aClip) const |
| void | AppendClippedContour (Outline &aDest, const Rect &aClip) const |
| size_t | AppendSplitContour (Outline &aDest, const PointFP &aLineStart, const PointFP &aLineVector) |
| Contour | TruncatedContour (double aStart, double aEnd) const |
| Contour | SubContourBetweenFractionalPoints (double aStartIndex, double aEndIndex) const |
| Contour | SubContourBetweenNearestPoints (const PointFP *aStartPoint, const PointFP *aEndPoint) const |
| Contour | CentralPath (std::shared_ptr< CEngine > aEngine, const Rect &aClip, bool aFractionalPixels, Line &aFallbackLine, bool aFallbackMustBeHorizontal) const |
| Contour | Smooth (double aRadius) const |
| Contour | ConcaveHull (double aMaxEdgeLength, PolygonOrientation aAssumedOrientation=PolygonOrientation::None) const |
| bool | MayIntersect (const Rect &aRect) const |
| bool | Intersects (const Rect &aRect) const |
| PathIntersectionType | IntersectionType (const MContour &aOther, double *aDistance=nullptr, PointFP *aNearest1=nullptr, PointFP *aNearest2=nullptr) const |
| PathIntersectionInfo | IntersectionInfo (const MContour &aOther) const |
| double | DistanceFrom (const MContour &aOther, PointFP *aNearest1=nullptr, PointFP *aNearest2=nullptr, PathIntersectionType *aType=nullptr) const |
| double | DistanceFromPoint (const PointFP &aPoint, PointFP *aNearest=nullptr, double *aNearestLength=nullptr, bool *aLeft=nullptr, size_t *aLineIndex=nullptr, double *aFractionalLineIndex=nullptr, bool aTreatAsOpen=false) const |
| PointFP | PointAtLength (double aLength, double aOffset=0, int32_t *aLineIndex=nullptr) const |
| CartoTypeCore::Point | Orientation (const CartoTypeCore::Point &aCenter) const |
| void | GetPrincipalAxis (PointFP &aCenter, PointFP &aVector) const |
| void | Write (OutputStream &aOutput) const |
| void | GetAngles (double aDistance, double &aStartAngle, double &aEndAngle) |
 Public Member Functions inherited from CartoTypeCore::MPath | |
| virtual | ~MPath () |
| virtual size_t | Contours () const =0 |
| virtual ContourView | ContourByIndex (size_t aIndex) const =0 |
| virtual bool | MayHaveCurves () const =0 |
| template<class MPathTraverser > | |
| void | Traverse (MPathTraverser &aTraverser, const Rect &aClip) const |
| template<class MPathTraverser > | |
| void | Traverse (MPathTraverser &aTraverser, const Rect *aClip=nullptr) const |
| bool | operator== (const MPath &aOther) const |
| Rect | CBox () const |
| bool | CBoxBiggerThan (int32_t aSize) const |
| bool | IsContainedIn (const Rect &aRect) const |
| bool | Contains (double aX, double aY) const |
| bool | Contains (const Point &aPoint) const |
| bool | Contains (const PointFP &aPoint) const |
| bool | MayIntersect (const Rect &aRect) const |
| bool | MayIntersect (const Rect &aRect, int32_t aBorder) const |
| bool | Intersects (const Rect &aRect) const |
| bool | Intersects (const MPath &aPath, const Rect *aBounds=nullptr) const |
| int32_t | MaxDistanceFromOrigin () const |
| PathIntersectionType | IntersectionType (const MPath &aOther, double *aDistance=nullptr, PointFP *aNearest1=nullptr, PointFP *aNearest2=nullptr) const |
| PathIntersectionInfo | IntersectionInfo (const MPath &aOther) const |
| double | DistanceFrom (const MPath &aOther, PointFP *aNearest1=nullptr, PointFP *aNearest2=nullptr, PathIntersectionType *aType=nullptr) const |
| double | DistanceFromPoint (const PointFP &aPoint, PointFP *aNearest=nullptr, size_t *aContourIndex=nullptr, size_t *aLineIndex=nullptr, double *aFractionaLineIndex=nullptr, bool aTreatAsOpen=false) const |
| bool | IsClippingNeeded (const Rect &aClip) const |
| Outline | Copy () const |
| Outline | ClippedPath (const Rect &aClip) const |
| Outline | ClippedPath (const MPath &aClip) const |
| Outline | ClippedPath (const ClipRegion &aClip) const |
| Outline | Clip (ClipOperation aClipOperation, const MPath &aClip) const |
| Outline | Envelope (double aOffset) const |
| Outline | ConcaveHull (double aMaxEdgeLength, PolygonOrientation aAssumedOrientation=PolygonOrientation::None) const |
| bool | IsSmoothingNeeded () const |
| Outline | SmoothPath () const |
| Outline | FlatPath (double aMaxDistance) const |
| Outline | TruncatedPath (double aStart, double aEnd) const |
| Outline | OffsetPath (double aOffset) const |
| Outline | TransformedPath (const AffineTransform &aTransform) const |
| Outline | TransformedPath (DrawResult &aError, MPointTransformer &aTransformer, int32_t aFractionalBits) const |
| Outline | Interpolate (int32_t aGranularity) const |
| std::array< Line, 3 > | HorizontalPaths (GraphicsContext *aGc, int32_t aPathLength, int32_t aLabelAscent, int32_t aLabelDescent, const PointFP &aUpVector, const Rect *aBounds, const Rect *aClip) const |
| PointFP | CenterOfGravity () const |
| double | Length () const |
| double | Area () const |
| PointFP | PointAtLength (double aPos) const |
| std::pair< Point, bool > | End () const |
| void | Write (OutputStream &aOutput) const |
| void | WriteAsXml (OutputStream &aOutput) const |
| bool | IsEmpty () const |
| bool | IsPoint () const |
| bool | IsGridOrientedRectangle (Rect *aRect=nullptr) const |
| void | GetSphericalAreaAndLength (const Projection &aProjection, double *aArea, double *aLength) const |
| CartoTypeCore::ClipType | ClipType (const Rect &aRect) const |
| bool | HasCurves () const |
| size_t | PointCount () const |
| ConstIter | begin () const |
| ConstIter | end () const |
Detailed Description
An MContour is an abstract interface to a sequence of integer points representing a line or polygon. The points may be on-curve or off-curve. Off-curve points are control points for quadratic or cubic spline curves. A contour may be open or closed.
Member Function Documentation
◆ Anticlockwise()
| bool CartoTypeCore::MContour::Anticlockwise | ( | ) | const |
Returns whether the contour has an anticlockwise orientation (assuming x coordinates go right and y coordinates go up). Algorithm from comp.graphics.algorithms FAQ 2.07. Assumes the contour is closed.
◆ AppendClippedContour()
Appends this contour to aDest, clipped to aClip.
◆ AppendSplitContour()
| size_t CartoTypeCore::MContour::AppendSplitContour | ( | Outline & | aDest, |
| const PointFP & | aLineStart, | ||
| const PointFP & | aLineVector | ||
| ) |
Splits the contour using a line from aLineStart in the direction aLineVector and appends the split parts to aDest. The return value is the number of returned contours that are to the left of the line.
◆ CentralPath()
| Contour CartoTypeCore::MContour::CentralPath | ( | std::shared_ptr< CEngine > | aEngine, |
| const Rect & | aClip, | ||
| bool | aFractionalPixels, | ||
| Line & | aFallbackLine, | ||
| bool | aFallbackMustBeHorizontal | ||
| ) | const |
Creates a central path for a contour.
As a fallback to be used if the central path is too short for a label, the function returns a straight line intersecting the polygon in aFallbackLine; if the fallback line is (0,0) - (0,0), no fallback line could be created.
If aFallbackMustBeHorizontal is true force the fallback line to be horizontal.
◆ ClippedContour()
Clips the contour to the specified rectangle.
All generated points are within or on the edge of the the rectangle, using the Sutherland Hodgman polygon clipping algorithm (http://www.cs.fit.edu/~wds/classes/graphics/Clip/clip/clip.html) This version is slightly modified for efficiency and considers two edges at the same time, in order to save creation of intermediate contours on the heap.
◆ Closed()
|
pure virtual |
Returns true if this is a closed contour.
Implemented in CartoTypeCore::ContourView, CartoTypeCore::SimpleContourData, CartoTypeCore::ContourBase< T >, CartoTypeCore::ContourBase< OutlinePoint >, CartoTypeCore::ContourBase< Point >, CartoTypeCore::WritableContourView, and CartoTypeCore::FixedSizeContour< aPointCount, aClosed >.
◆ ConcaveHull()
| Contour CartoTypeCore::MContour::ConcaveHull | ( | double | aMaxEdgeLength, |
| PolygonOrientation | aAssumedOrientation = PolygonOrientation::None |
||
| ) | const |
Creates a concave hull for a closed contour, with a maximum desired edge length of aMinEdgeLength. If this contour is unclosed it returns the original contour.
◆ Contains() [1/2]
|
inline |
Returns true if this contour contains aPoint.
◆ Contains() [2/2]
| bool CartoTypeCore::MContour::Contains | ( | double | aX, |
| double | aY | ||
| ) | const |
Return true if the contour contains the point (aX,aY).
◆ Contours()
|
inlinevirtual |
Returns the number of contours.
Implements CartoTypeCore::MPath.
Reimplemented in CartoTypeCore::ContourBase< T >, CartoTypeCore::ContourBase< OutlinePoint >, and CartoTypeCore::ContourBase< Point >.
◆ DistanceFrom()
| double CartoTypeCore::MContour::DistanceFrom | ( | const MContour & | aOther, |
| PointFP * | aNearest1 = nullptr, |
||
| PointFP * | aNearest2 = nullptr, |
||
| PathIntersectionType * | aType = nullptr |
||
| ) | const |
Finds the distance between two contours. aNearest1 and aNearest2, if non-null, are used to return the nearest points on this contour and the other contour respectively. aType, if non-null, is used to return the intersection type.
This function ignores curves, and does not handle self-intersecting paths.
If one of the contours contains or intersects the other, the distance returned is zero, and aNearest1 and aNearest2 are both set to the first intersection if there is one, or to the first point of the contained contour if not.
If either contour is empty, this function returns CT_DBL_MAX (the largest possible number).
◆ DistanceFromPoint()
| double CartoTypeCore::MContour::DistanceFromPoint | ( | const PointFP & | aPoint, |
| PointFP * | aNearest = nullptr, |
||
| double * | aNearestLength = nullptr, |
||
| bool * | aLeft = nullptr, |
||
| size_t * | aLineIndex = nullptr, |
||
| double * | aFractionalLineIndex = nullptr, |
||
| bool | aTreatAsOpen = false |
||
| ) | const |
Find the distance from a point to a contour.
This function ignores curves. It treats the contour as a series of straight lines.
If the contour is open (a polyline) the distance is to the nearest point on a line segment. If the contour is closed (a polygon) the distance is zero if the point is inside, otherwise it is the distance to the nearest point on an edge.
If aNearest is non-null use it to return the coordinates of the nearest point on the contour, or the original point if the contour is closed and the point is inside.
If aNearestLength is non-null return the length, measured along the path, of the nearest point.
If aLeft is non-null return a value indicating whether the point is left of the line or right of it.
If aLineIndex is non-null return the index of the line containing the nearest point, or npos if there are fewer than 2 points. If aFractionalLineIndex is non-null return the fractional line index (e.g., 4.5 if the point is half way between points 4 and 5) of the nearest point, or 0 if there are fewer than 2 points or the contour is closed and the point is inside.
If aTreatAsOpen is true, treat the contour as open even if it is closed, and therefore return a non-zero distance even if the point is inside the contour.
If the contour is empty return CT_DBL_MAX (the largest possible number).
◆ FractionalPoint()
| OutlinePoint CartoTypeCore::MContour::FractionalPoint | ( | double | aIndex | ) | const |
Return a point selected by a fractional index. The fraction is the proportion of the length between one point and the next. The point returned is always on-curve; this function is not usable for curved contours.
◆ GetAngles()
| void CartoTypeCore::MContour::GetAngles | ( | double | aDistance, |
| double & | aStartAngle, | ||
| double & | aEndAngle | ||
| ) |
Get the start and end angles of a path in radians. The start angle is the bearing from the start point to a point aDistance along the path, or to the end of the path if aDistance is longer than the path. The start angle is the bearing from the end point to a point aDistance back along the path, or to the start of the path if aDistance is longer than the path.
◆ GetPrincipalAxis()
Get the principal axis of a contour, which must be a closed contour with at least 3 points, in the form of its center of gravity and a vector pointing in the direction of the axis.
◆ IntersectionInfo()
| PathIntersectionInfo CartoTypeCore::MContour::IntersectionInfo | ( | const MContour & | aOther | ) | const |
Returns information about the intersection of this contour with another one.
◆ IntersectionType()
| PathIntersectionType CartoTypeCore::MContour::IntersectionType | ( | const MContour & | aOther, |
| double * | aDistance = nullptr, |
||
| PointFP * | aNearest1 = nullptr, |
||
| PointFP * | aNearest2 = nullptr |
||
| ) | const |
Returns the relationship between two contours as a path intersection type.
Other information can optionally be obtained.
If aDistance is non-null it is used to return the distance between the two contours, or zero if they intersect.
aNearest1 and aNearest2, if non-null, are used to return the nearest points on this contour and the other contour respectively.
This function ignores curves, and does not handle self-intersecting paths.
If one of the contours contains or intersects the other, the distance returned is zero, and aNearest1 and aNearest2 are both set to the first intersection if there is one, or to the first point of the contained contour if not.
If either contour is empty, this function returns PathIntersectionType::Separate, and sets the other return values to CT_DBL_MAX (the largest possible number).
◆ Intersects()
| bool CartoTypeCore::MContour::Intersects | ( | const Rect & | aRect | ) | const |
Return true if the path intersects a specified rectangle. For single points, this is true if the point is inside the rectangle. For open paths, this is true if at least one line intersects the rectangle. For closed paths, the polygon defined by the control points must intersect the rectangle.
◆ IsGridOrientedRectangle()
| bool CartoTypeCore::MContour::IsGridOrientedRectangle | ( | Rect * | aRect = nullptr | ) | const |
Determine whether a contour is a grid-oriented rectangle and return the rectangle if so, and if aRect is non-null.
◆ LastPoint()
|
inline |
Returns the last point of the contour.
◆ MayIntersect()
| bool CartoTypeCore::MContour::MayIntersect | ( | const Rect & | aRect | ) | const |
Return true if the contour may possibly intersect the specified rectangle.
Return false if there is definitely no intersection. For contours with a single point, the return value is whether the point is in the rectangle.
A closed contour is treated as a polygon. The return value indicates whether the bounding box of the path's control points intersects the rectangle.
An unclosed contour is treated as a point or a line. The return value indicates whether the bounding box of the control points of the line segments and curves making up the line intersects the rectangle.
◆ operator ContourView()
|
inline |
Returns a ContourView object representing this contour.
◆ Orientation() [1/2]
| PolygonOrientation CartoTypeCore::MContour::Orientation | ( | ) | const |
Returns the orientation of a polygon.
◆ Orientation() [2/2]
| Point CartoTypeCore::MContour::Orientation | ( | const CartoTypeCore::Point & | aCenter | ) | const |
Return the orientation of the contour, given the center of gravity. This is also called the Principal axis transformation of the polygon. Algorithm based on the following quote from comp.graphics.algorithms (slightly edited), full thread called "polygon major axis anyone", by Hans-Bernard Broeker : The calculation of the (centered) second moments is what gives you the angle. There are actually 3 independent second moments: Ixx, Iyy, and Ixy. These form a symmetric 2x2 matrix:
(Ixx Ixy)
(Ixy Iyy)
The "second moments" are actually the principal second moments, i.e. the second moments in a coordinate system (x', y') that has been rotated relative to the present one such that Ix'y' is zero, and optionally also Ix'x' >= Iy'y'.
They're found by doing an eigenvector/eigenvalue analysis on that 2x2 matrix, also known as the 'principal axis transformation' in this context. -end of quote
Also refer to: http://kwon3d.com/theory/moi/prin.html for an explanation of principal axis.
◆ Point()
|
pure virtual |
Returns a point selected by its index.
Implemented in CartoTypeCore::ContourView, CartoTypeCore::SimpleContourData, CartoTypeCore::ContourBase< T >, CartoTypeCore::ContourBase< OutlinePoint >, CartoTypeCore::ContourBase< Point >, CartoTypeCore::WritableContourView, and CartoTypeCore::FixedSizeContour< aPointCount, aClosed >.
◆ PointAtLength()
| PointFP CartoTypeCore::MContour::PointAtLength | ( | double | aLength, |
| double | aOffset = 0, |
||
| int32_t * | aLineIndex = nullptr |
||
| ) | const |
Get a point at a certain length, measured along the contour. If aLength is negative, return the first point. If aLength is greater than the length of the contour, return the last point.
If aOffset is non-zero, offset the point from the contour by that amount, which may be positive (for offsets to the left) or negative (for offsets to the right). The meanings of 'right' and 'left' assume that Y coordinates increase upwards.
If aLineIndex is non-null return the index of the line containing the point, or -1 if there are fewer than 2 points.
◆ Points()
|
pure virtual |
Returns the number of points in the contour.
Implemented in CartoTypeCore::ContourView, CartoTypeCore::SimpleContourData, CartoTypeCore::ContourBase< T >, CartoTypeCore::ContourBase< OutlinePoint >, CartoTypeCore::ContourBase< Point >, CartoTypeCore::WritableContourView, and CartoTypeCore::FixedSizeContour< aPointCount, aClosed >.
◆ Smooth()
| Contour CartoTypeCore::MContour::Smooth | ( | double | aRadius | ) | const |
Creates a smoothed version of a contour.
Simplification consists in removing all points with an area less than aResolutionArea. A point's area is the area of the triangle made by the point and its two neighbours.
The start and end of an open contour are not removed. Closed contours may be reduced to nothing.
◆ SubContourBetweenFractionalPoints()
| Contour CartoTypeCore::MContour::SubContourBetweenFractionalPoints | ( | double | aStartIndex, |
| double | aEndIndex | ||
| ) | const |
Creates a subcontour of this contour from one fractional point index to another. If this contour has more than one point the returned contour contains at least two points.
◆ SubContourBetweenNearestPoints()
| Contour CartoTypeCore::MContour::SubContourBetweenNearestPoints | ( | const PointFP * | aStartPoint, |
| const PointFP * | aEndPoint | ||
| ) | const |
Creates a subcontour of this contour between the nearest points on the contour to two points. If aStartPoint is null the first point is used. If aEndPoint is null the last point is used.
◆ TruncatedContour()
| Contour CartoTypeCore::MContour::TruncatedContour | ( | double | aStart, |
| double | aEnd | ||
| ) | const |
Returns a version of the contour truncated by removing a length equal to aStart at the start, and a length equal to aEnd at the end.
Either aStart or aEnd may be zero or negative; negative values cause extension instead of truncation.
This function treats all points as on-curve points, and therefore does not work properly for contours containing curves.
◆ Write()
| void CartoTypeCore::MContour::Write | ( | OutputStream & | aOutput | ) | const |
Writes this contour in serialized form.
The documentation for this class was generated from the following files:
- cartotype_path.h
- cartotype_contour.cpp
