Some generic methods compiled into one class. Methods that describe: More...

#include <Utilities.h>

Static Public Member Functions
static QColor	getQColor (const osg::Vec4f &color)

static osg::Vec4f	getOsgColor (const QColor &color)

static bool	areStrokesProjectable (const std::vector< entity::Stroke > &strokes, entity::Canvas source, entity::Canvas target, osg::Camera camera)

static bool	getViewProjectionWorld (osgGA::GUIActionAdapter &aa, osg::Matrix &VPW, osg::Matrix &invVPW)

static void	getFarNear (double x, double y, const osg::Matrix &invVPW, osg::Vec3f &near, osg::Vec3f &far)

static bool	getRayPlaneIntersection (const osg::Plane &plane, const osg::Vec3f &center, const osg::Vec3f &nearPoint, const osg::Vec3f &farPoint, osg::Vec3f &P, bool isLine=false)

static bool	getModel (entity::Canvas *canvas, osg::Matrix &M, osg::Matrix &invM)

static bool	getLocalFromGlobal (const osg::Vec3f &P, const osg::Matrix &invM, osg::Vec3f &p)

static bool	getGlobalFromLocal (const osg::Vec3f &p, const osg::Matrix &M, osg::Vec3f &P)

static double	getAngleTwoVectors (const osg::Vec2f &p1, const osg::Vec2f &p2, const osg::Vec2f &p3, const osg::Vec2f &p4)

static osg::Vec3f	rotate2DPointAround (const osg::Vec3f &center, float theta, const osg::Vec3f &original)

static bool	getSkewLinesProjection (const osg::Vec3f &center, const osg::Vec3f &farPoint, const osg::Vec3f &nearPoint, const osg::Vec3f &normal, osg::Vec3f &X1)

static double	getSkewLinesDistance (const osg::Vec3d &r1, const osg::Vec3d &r2, const osg::Vec3d &v1, const osg::Vec3d &v2)

static bool	getLinesIntersection (const osg::Vec3f &La1, const osg::Vec3f &La2, const osg::Vec3f &Lb1, const osg::Vec3f &Lb2, osg::Vec3f &intersection)

static int	getCanvasesIntersection (entity::Canvas current, entity::Canvas previous, osg::Vec3f &p1, osg::Vec3f &p2, osg::Vec3f &p3, osg::Vec3f &p4)

static int	getPlanesIntersection (entity::Canvas canvas1, entity::Canvas canvas2, osg::Vec3f &iP, osg::Vec3f &u)

static osg::Vec3f	projectPointOnLine (const osg::Vec3f &iP, const osg::Vec3f &u, const osg::Vec3f &P)

static double	distanceTwoPoints (const osg::Vec3f &P1, const osg::Vec3f &P2)

static osg::Vec3f	getAnchorLineSegment (const osg::Vec3f &P0, const osg::Vec3f &P1)

static QCursor	getCursorFromMode (cher::MOUSE_MODE mode)

static bool	getCameraPosition (entity::SVMData *svm, osg::Vec3f &eye, osg::Vec3f &center, osg::Vec3f &up)

Detailed Description

Some generic methods compiled into one class. Methods that describe:

The relationships between screen coordinates and world coordinates.
The relationships between local system of coordinates and global system of coordinates.
Color convertions between Qt and OSG libraries.
Geometric derivations such as distance between skew lines.

Member Function Documentation

§ areStrokesProjectable()

bool Utilities::areStrokesProjectable	(	const std::vector< entity::Stroke *> &	strokes,
		entity::Canvas *	source,
		entity::Canvas *	target,
		osg::Camera *	camera
	)

static

A tester method in order to check if a set of strokes can be projected into a selected canvas under the given view point.

Parameters

strokes	is the set of selected strokes
source	is the Canvas which contains the set of strokes to project
target	is the Canvas on which the projection should be done
camera	is the camera view true if all the strokes can be projected successfully.

§ distanceTwoPoints()

double Utilities::distanceTwoPoints	(	const osg::Vec3f &	P1,
		const osg::Vec3f &	P2
	)

static

A method to estimate Euclidean distance between two points in 3D.

Parameters

P1	is the first 3D point.
P2	is the second 3D point.

Returns: Euclidean distance according to https://en.wikipedia.org/wiki/Euclidean_distance

§ getAnchorLineSegment()

osg::Vec3f Utilities::getAnchorLineSegment	(	const osg::Vec3f &	P0,
		const osg::Vec3f &	P1
	)

static

A method to obtain coordinate of the second point of entity::LineSegment which is anchored to canvas' local u and v coordinates.

Parameters

canvas	is the canvas within which the segment is drawn.
P0	is the first point of segment,
P1	is the second point on segment, which is a subject to change to the result point.

Returns: local anchored point.

§ getAngleTwoVectors()

double Utilities::getAngleTwoVectors	(	const osg::Vec2f &	p1,
		const osg::Vec2f &	p2,
		const osg::Vec2f &	p3,
		const osg::Vec2f &	p4
	)

static

A method which obtains an angle between two vectors in 2d. For more info, see: http://www.euclideanspace.com/maths/algebra/vectors/angleBetween/index.htm .

Parameters

p1	is the first point of the first vector.
p2	is the second point of the first vector.
p3	is the first point of the second vector.
p4	is the second point of the second vector.

Returns: an angle between two vectors in radians.

§ getCameraPosition()

bool Utilities::getCameraPosition	(	entity::SVMData *	svm,
		osg::Vec3f &	eye,
		osg::Vec3f &	center,
		osg::Vec3f &	up
	)

static

A method to obtain camera pose given 4 intersecting rays (obtained from entity::SVMData). The algorithm is as follows: first, find 4 intersections between each neighboring rays (or use all possible pair?). Second, calculate the camera eye - average of the calculated four intersections. The camera's center vector passes through one of the wire's centers, and the up vector is always constant - (0,1,0).

Returns: true if the parameters were calculated successfully, false otherwise.

§ getCanvasesIntersection()

int Utilities::getCanvasesIntersection	(	entity::Canvas *	current,
		entity::Canvas *	previous,
		osg::Vec3f &	p1,
		osg::Vec3f &	p2,
		osg::Vec3f &	p3,
		osg::Vec3f &	p4
	)

static

A method to obtain intersection between two canvases (planes) so that to do projection on the intersection onto the second canvas.

Parameters

current	is the first canvas
previous	is the second canvas (where the intersection will be cast on)
p1

§ getCursorFromMode()

QCursor Utilities::getCursorFromMode ( cher::MOUSE_MODE mode )

static

UI method to obtain cursor data based on the given mouse mode.

§ getFarNear()

void Utilities::getFarNear	(	double	x,
		double	y,
		const osg::Matrix &	invVPW,
		osg::Vec3f &	near,
		osg::Vec3f &	far
	)

static

A method to obtain far and near points of the screen point that cast a projection ray.

Parameters

x	- x-coordinate of the screen
y	- y-coordinate of the screen
invVPW	- inverse matrix of View-Projection-World matrix
near	is the result 3D point on the near point on the cast ray
far	is the result 3D point as the far point on the cast ray.

Returns: true if the points were obtained successfully.

See also: getViewProjectionWorld().

§ getGlobalFromLocal()

bool Utilities::getGlobalFromLocal	(	const osg::Vec3f &	p,
		const osg::Matrix &	M,
		osg::Vec3f &	P
	)

static

A method which is inverse to the method getLocalFromGlobal().

See also: getModel(), getLocalFromGlobal().

§ getLinesIntersection()

bool Utilities::getLinesIntersection	(	const osg::Vec3f &	La1,
		const osg::Vec3f &	La2,
		const osg::Vec3f &	Lb1,
		const osg::Vec3f &	Lb2,
		osg::Vec3f &	intersection
	)

static

A method to obtain an intersection between the two lines. Each line is presented by two points in 3D space. The algorithm treats the lines as skew and the intersection is calculated as average between two projections on each line. The projection between the skew lines is a shortest distance between the lines.

Parameters

La1	is the first 3D point on first line.
La2	is the second 3D point on first line.
Lb1	is the first 3D point on second line.
Lb2	is the second 3D point on second line.
intersection	is the result intersection.

Returns: true if the intersection calculation was successful.

§ getLocalFromGlobal()

bool Utilities::getLocalFromGlobal	(	const osg::Vec3f &	P,
		const osg::Matrix &	invM,
		osg::Vec3f &	p
	)

static

A method to convert a global point into local system of coordinates.

Parameters

P	is the requested point to convert
invM	is an inverted model matrix
p	is the result 2D point (local system of coordinates).

Returns: true is derivation passed successfully.

See also: getModel(), getLocalFromGlobal()

§ getModel()

bool Utilities::getModel	(	entity::Canvas *	canvas,
		osg::Matrix &	M,
		osg::Matrix &	invM
	)

static

A method to obtain model matrix (global to local conversion matrix) from a given canvas.

Parameters

canvas	is the 2D plane canvas from which to derive the model matrix
M	is the result model matrix
invM	is the result inverse of model matrix

Returns: true if model matrices were obtaibed successfully.

§ getOsgColor()

osg::Vec4f Utilities::getOsgColor ( const QColor & color )

static

A method to convert a Qt color representation into an OSG.

See also: getQColor().

§ getPlanesIntersection()

int Utilities::getPlanesIntersection	(	entity::Canvas *	canvas1,
		entity::Canvas *	canvas2,
		osg::Vec3f &	iP,
		osg::Vec3f &	u
	)

static

A method to obtaib intersection between two planes. For more details on the algorithm, see: http://geomalgorithms.com/a05-_intersect-1.html

§ getQColor()

QColor Utilities::getQColor ( const osg::Vec4f & color )

static

A method to convert an OSG color representation into a Qt

See also: getQColor().

§ getRayPlaneIntersection()

bool Utilities::getRayPlaneIntersection	(	const osg::Plane &	plane,
		const osg::Vec3f &	center,
		const osg::Vec3f &	nearPoint,
		const osg::Vec3f &	farPoint,
		osg::Vec3f &	P,
		bool	isLine = `false`
	)

static

A method to obtain intersection point between a given plane and a line (ray).

Parameters

plane	is the given plane
center	is an arbitrary point on the plane that represents the plane's center (global coordinates).
nearPoint	is the 3D near point of the ray that was cast from a screen point
farPoint	is the 3D far point of the ray that was cast from a screen point
P	is the result point that represents intersection of the plane and a ray that is given by far and near points
isLine	is boolean indicating whether we deal with ray (false) or line (true). Ray may not intersect the plane if both points lie above or below the plane.

Returns: true if the point was obtained without any errors

See also: getFarNear()

§ getSkewLinesDistance()

double Utilities::getSkewLinesDistance	(	const osg::Vec3d &	r1,
		const osg::Vec3d &	r2,
		const osg::Vec3d &	v1,
		const osg::Vec3d &	v2
	)

static

A method to obtain a distance between skew rays. For more info, see: https://en.wikipedia.org/wiki/Skew_lines

See also: getSkewLinesProjection()

§ getSkewLinesProjection()

bool Utilities::getSkewLinesProjection	(	const osg::Vec3f &	center,
		const osg::Vec3f &	farPoint,
		const osg::Vec3f &	nearPoint,
		const osg::Vec3f &	normal,
		osg::Vec3f &	X1
	)

static

A method to obtain a distance between skew lines. For more info, see: http://www2.washjeff.edu/users/mwoltermann/Dorrie/69.pdf or here: http://paulbourke.net/geometry/pointlineplane/

Parameters

center	is the first point P1 (see notations in the link above)
farPoint	is to describe the line on which P1 lies
nearPoint	is the second point P2
normal	is to describe the line on which P2 lies
X1	is the projection point on first line onto second line

Returns: true if point was obtained successfully.

See also: getSkewLinesDistance()

§ getViewProjectionWorld()

bool Utilities::getViewProjectionWorld	(	osgGA::GUIActionAdapter &	aa,
		osg::Matrix &	VPW,
		osg::Matrix &	invVPW
	)

static

A method to obtain two matrices - VPW and its invertse given the action adapter.

Parameters

aa	is OSG-based variable from which camera, view and other matrices can be derived.
VPW	is the output View-Projection-World matrix
invVPW	is the ourput inverse of View-Projection-World matrix.

Returns: true if both matrices were obtained without an error.

§ projectPointOnLine()

osg::Vec3f Utilities::projectPointOnLine	(	const osg::Vec3f &	iP,
		const osg::Vec3f &	u,
		const osg::Vec3f &	P
	)

static

A method to project 3d point onto 3D line.

Parameters

iP	is the global point on the line.
u	is the vector defining the line direction.
P	is the point to project.

Returns: global coordinate of the projected point.

§ rotate2DPointAround()

osg::Vec3f Utilities::rotate2DPointAround	(	const osg::Vec3f &	center,
		float	theta,
		const osg::Vec3f &	original
	)

static

A method to rotate a 2D point around another point on a specified angle. The input and output points have "local point" format: [u,v,0].

Parameters

center	is the point around which the rotation will be done.
theta	is the angle of rotation in radians.
original	is the point to rotate.

Returns: the result rotated point.

The documentation for this class was generated from the following files:

src/cherish/Utilities.h
src/cherish/Utilities.cpp

Static Public Member Functions

Detailed Description

Member Function Documentation

§ areStrokesProjectable()

§ distanceTwoPoints()

§ getAnchorLineSegment()

§ getAngleTwoVectors()

§ getCameraPosition()

§ getCanvasesIntersection()

§ getCursorFromMode()

§ getFarNear()

§ getGlobalFromLocal()

§ getLinesIntersection()

§ getLocalFromGlobal()

§ getModel()

§ getOsgColor()

§ getPlanesIntersection()

§ getQColor()

§ getRayPlaneIntersection()

§ getSkewLinesDistance()

§ getSkewLinesProjection()

§ getViewProjectionWorld()

§ projectPointOnLine()

§ rotate2DPointAround()