Draw Class Reference

A very simple drawing environment, originally to visualize planner stuff. More...

#include <Draw.h>

Detailed Description

A very simple drawing environment, originally to visualize planner stuff.

Default origin is in the lower left corner, positive x and y to the right and up

Definition at line 12 of file Draw.h.

Public Types
enum	Colors { BLACK, DK_GRAY, GRAY, LT_GRAY, WHITE, RED, YELLOW, GREEN, CYAN, BLUE, MAGENTA }
	Convenient color constants. More...
enum	PointStyles { CIRCLE, SQUARE, DIAMOND }
	Provides different point() styles. More...
Public Member Functions
	Draw ()
	Default constructor, must still call setFile() before any drawing commands.
	Draw (const std::string &file, double width, double height)
	Constructor, sets up output.
	~Draw ()
	Destructor.
Draw &	setFile (const std::string &file, double width, double height)
	This must be called to setup output destination before calling any drawing commands.
Draw &	flushPage ()
	Writes the current page and starts a new one.
Draw &	setOrigin (const fmat::Column< 2 > &p)
	Moves the origin (lower left corner).
Draw &	setOrigin (double x, double y)
	Moves the origin (lower left corner).
Draw &	centerView (const fmat::Column< 2 > &p)
	Moves the origin in order to center the viewport on the specified point.
Draw &	centerView (double x, double y)
	Moves the origin in order to center the viewport on the specified point.
Draw &	setClip ()
	Clips further drawing to the current path area.
Draw &	clearClip ()
	Clears the clipping region.
Draw &	setScale (double x, bool scaleStroke=false)
	Changes the scaling factor, to display more or less within the bounds given to setFile().
double	displayToScaled (double x) const
	Converts from display units to scaled coordinates.
double	scaledToDisplay (double x) const
	Converts from scaled coordinates to display units.
Draw &	setRegion (const BoundingBox2D &region, bool scaleStroke=false)
	Changes scale and origin to fit the specified drawing region to the output.
Draw &	drawGrid (double xRes, double yRes, double xOff=0, double yOff=0)
	Draws a grid of the specified horizontal and vertical resolution across the visible region (doesn't stroke).
Draw &	drawAxes ()
	Draws the axes across the visible region (doesn't stroke).
Draw &	setStrokeWidth (double x)
	Sets the stroke width using output dimension units, i.e. scale factor invariant.
Draw &	setScaledStrokeWidth (double x)
	Sets the stroke width using coordinate-space units, i.e. relative to scale factor.
double	getStrokeWidth () const
	Returns the stroke width in output dimension units.
double	getScaledStrokeWidth () const
	Returns the stroke width in coordinate-space units.
Draw &	setColorRGB (double red, double green, double blue, double alpha=1)
	Sets the color for future drawing operations.
Draw &	setColorGray (double x, double alpha=1)
	Sets the color for future drawing operations.
Draw &	setColor (Colors c, double alpha=1)
	Sets the color for future drawing operations.
Draw &	stroke ()
	Outline the current path.
Draw &	stroke (Colors c, double alpha=1)
	Outline the current path with specified color.
Draw &	stroke (double red, double green, double blue, double alpha=1)
	Outline the current path with specified color.
Draw &	strokeLine (const fmat::Column< 2 > &p1, const fmat::Column< 2 > &p2)
	Stroke a single line; if drawing a polygon, better to use lineTo and stroke as a batch.
Draw &	strokeLine (double x1, double y1, double x2, double y2)
	Stroke a single line; if drawing a polygon, better to use lineTo and stroke as a batch.
Draw &	fill ()
	Paint the current path.
Draw &	fill (Colors c, double alpha=1)
	Paint the current path with specified color.
Draw &	fill (double red, double green, double blue, double alpha=1)
	Paint the current path with specified color.
Draw &	point (const fmat::Column< 2 > &p, double size, PointStyles style=CIRCLE)
	Produces a output-dimension (i.e. unscaled) symbol at the specified point (follow up with fill() and/or stroke()).
Draw &	point (double x, double y, double size, PointStyles style=CIRCLE)
	Produces a output-dimension (i.e. unscaled) symbol at the specified point (follow up with fill() and/or stroke()).
Draw &	arc (const fmat::Column< 2 > &p, double r, double begin, double end)
	Produces an arc of the specified range.
Draw &	arc (double x, double y, double r, double begin, double end)
	Produces an arc of the specified range.
Draw &	circle (const fmat::Column< 2 > &c, double r)
	Produces a closed path for a circle at the specified point.
Draw &	circle (double x, double y, double r)
	Produces a closed path for a circle at the specified point.
Draw &	ellipse (const fmat::Column< 2 > &c, double width, double height, double orientation=0)
	Produces an ellipse, note width and height, not major/minor.
Draw &	rect (const BoundingBox2D &r)
	Produces a closed path for an axis-aligned rectangle.
Draw &	rect (const fmat::Column< 2 > &p1, const fmat::Column< 2 > &p2)
	Produces a closed path for an axis-aligned rectangle between the specified points.
Draw &	arrow (const fmat::Column< 2 > &p1, const fmat::Column< 2 > &p2, double headWidth=2, double headLength=5)
	Draws a line between points with an arrowhead at p2, the headWidth and headLength are multiples of the stroke width.
Draw &	draw (const PlannerObstacle2D &o)
	Produces a closed path for a planner obstacle.
Draw &	draw (const RectangularObstacle &o)
	Produces a closed path for a planner obstacle.
Draw &	draw (const CircularObstacle &o)
	Produces a closed path for a planner obstacle.
Draw &	draw (const EllipticalObstacle &o)
	Produces a closed path for a planner obstacle.
Draw &	draw (const ConvexPolyObstacle &o)
	Produces a closed path for a planner obstacle.
Draw &	draw (const HierarchicalObstacle &o)
	Produces a closed path for a planner obstacle.
Draw &	moveTo (const fmat::Column< 2 > &p)
	Set the pen location without adding a line segment to the current path.
Draw &	moveTo (double x, double y)
	Set the pen location without adding a line segment to the current path.
Draw &	lineTo (const fmat::Column< 2 > &p)
	Add a line segment to the current path.
Draw &	lineTo (double x, double y)
	Add a line segment to the current path.
Draw &	arcTo (const fmat::Column< 2 > &p, double r, double begin, double end)
	Produces an arc of the specified range (continuing the current path).
Draw &	arcTo (double x, double y, double r, double begin, double end)
	Produces an arc of the specified range (continuing the current path).
Draw &	closePath ()
	Add a line segment back to the last moveTo location.
Draw &	holdPath (bool continuePath=false)
	Clears path unless continuePath is set, additional paths will be collected together until releasePath() is called.
Draw &	releasePath ()
	Clears the hold flag from holdPath(), but does not actually clear the path.
bool	getHoldMode () const
	Returns current hold setting.
Draw &	clearPath ()
	Erase current path, but does not reset holdPath() mode.
Protected Member Functions
void	teardown ()
	Flush pending output and release resources.
void	resetTransform ()
	Recomputes and applies the surface transform.
void	checkSurfaceStatus (const std::string &msg)
	Throws an exception if surface status is not success.
void	checkStatus (const std::string &msg)
	Throws an exception if either cairo or surface status is not success.
Protected Attributes
cairo_t *	cr
cairo_surface_t *	surface
std::string	filename
fmat::Column< 2 >	origin
double	scale
double	surfaceWidth
double	surfaceHeight
bool	addPath
	Indicates state of holdPath()/releasePath(), if true the path isn't cleared between draw calls.
Private Member Functions
	Draw (const Draw &o)
	Do not call.
Draw &	operator= (const Draw &o)
	Do not call.

Member Enumeration Documentation

enum Draw::Colors

Convenient color constants.

Enumerator:

BLACK
DK_GRAY
GRAY
LT_GRAY
WHITE
RED
YELLOW
GREEN
CYAN
BLUE
MAGENTA

Definition at line 70 of file Draw.h.

enum Draw::PointStyles

Provides different point() styles.

Enumerator:

CIRCLE
SQUARE
DIAMOND

Definition at line 102 of file Draw.h.

Constructor & Destructor Documentation

Draw::Draw ( )

Default constructor, must still call setFile() before any drawing commands.

Definition at line 15 of file Draw.h.

Draw::Draw	(	const std::string &	file,
		double	width,
		double	height
	)

Constructor, sets up output.

Definition at line 19 of file Draw.h.

Draw::~Draw ( )

Destructor.

Definition at line 23 of file Draw.h.

Draw::Draw ( const Draw & o ) [private]

Do not call.

Member Function Documentation

Draw & Draw::arc	(	double	x,
		double	y,
		double	r,
		double	begin,
		double	end
	)

Produces an arc of the specified range.

Definition at line 78 of file Draw.cc.

Draw& Draw::arc	(	const fmat::Column< 2 > &	p,
		double	r,
		double	begin,
		double	end
	)

Produces an arc of the specified range.

Definition at line 112 of file Draw.h.

Referenced by arc(), and circle().

Draw & Draw::arcTo	(	double	x,
		double	y,
		double	r,
		double	begin,
		double	end
	)

Produces an arc of the specified range (continuing the current path).

Definition at line 90 of file Draw.cc.

Draw& Draw::arcTo	(	const fmat::Column< 2 > &	p,
		double	r,
		double	begin,
		double	end
	)

Produces an arc of the specified range (continuing the current path).

Definition at line 159 of file Draw.h.

Referenced by arcTo().

Draw & Draw::arrow	(	const fmat::Column< 2 > &	p1,
		const fmat::Column< 2 > &	p2,
		double	headWidth = `2`,
		double	headLength = `5`
	)

Draws a line between points with an arrowhead at p2, the headWidth and headLength are multiples of the stroke width.

You can stroke to get a barbed head, or fill to get a little triangle. For a really perfect filled arrowhead, call closePath() first to avoid a little bit of mitred corners sticking out.

Definition at line 81 of file Draw.cc.

Draw & Draw::centerView	(	double	x,
		double	y
	)

Moves the origin in order to center the viewport on the specified point.

Definition at line 70 of file Draw.cc.

Draw& Draw::centerView ( const fmat::Column< 2 > & p )

Moves the origin in order to center the viewport on the specified point.

Definition at line 36 of file Draw.h.

Referenced by centerView(), and setRegion().

void Draw::checkStatus ( const std::string & msg ) [protected]

Throws an exception if either cairo or surface status is not success.

Definition at line 95 of file Draw.cc.

void Draw::checkSurfaceStatus ( const std::string & msg ) [protected]

Throws an exception if surface status is not success.

Definition at line 94 of file Draw.cc.

Draw& Draw::circle	(	double	x,
		double	y,
		double	r
	)

Produces a closed path for a circle at the specified point.

Definition at line 119 of file Draw.h.

Draw& Draw::circle	(	const fmat::Column< 2 > &	c,
		double	r
	)

Produces a closed path for a circle at the specified point.

Definition at line 117 of file Draw.h.

Draw & Draw::clearClip ( )

Clears the clipping region.

Definition at line 72 of file Draw.cc.

Draw & Draw::clearPath ( )

Erase current path, but does not reset holdPath() mode.

Definition at line 92 of file Draw.cc.

Referenced by holdPath().

Draw & Draw::closePath ( )

Add a line segment back to the last moveTo location.

Definition at line 91 of file Draw.cc.

double Draw::displayToScaled ( double x ) const

Converts from display units to scaled coordinates.

Definition at line 49 of file Draw.h.

Draw & Draw::draw ( const HierarchicalObstacle & o )