wrapper for cairo context which adds methods allowing for eigen vector typed points More...

#include <mpblocks/gtk/EigenCairo.h>

Classes
struct	SolidPattern

Public Member Functions
template<typename Derived >
void	arc (const Eigen::MatrixBase< Derived > &c, double radius, double angle1, double angle2)

template<typename Derived >
void	arc_negative (const Eigen::MatrixBase< Derived > &c, double radius, double angle1, double angle2)

template<typename Derived >
void	circle (const Eigen::MatrixBase< Derived > &c, double r)

template<typename Derived1 , typename Derived2 , typename Derived3 >
void	curve_to (const Eigen::MatrixBase< Derived1 > &x, const Eigen::MatrixBase< Derived2 > &c1, const Eigen::MatrixBase< Derived3 > &c2)

	EigenCairo (const Cairo::RefPtr< Cairo::Context > &ctx)

template<typename Derived >
void	line_to (const Eigen::MatrixBase< Derived > &v) const

template<typename Derived >
void	move_to (const Eigen::MatrixBase< Derived > &v) const

template<typename Derived1 , typename Derived2 >
void	rectangle (const Eigen::MatrixBase< Derived1 > &x, const Eigen::MatrixBase< Derived2 > &s)

template<typename Derived1 , typename Derived2 , typename Derived3 >
void	rel_curve_to (const Eigen::MatrixBase< Derived1 > &dx, const Eigen::MatrixBase< Derived2 > &dc1, const Eigen::MatrixBase< Derived3 > &dc2)

template<typename Derived >
void	rel_line_to (const Eigen::MatrixBase< Derived > &v)

template<typename Derived >
void	rel_move_to (const Eigen::MatrixBase< Derived > &v)

template<typename Derived >
void	scale (const Eigen::MatrixBase< Derived > &v)

void	set_source (const Gdk::RGBA &rgba)

void	set_source_rgb (const char *str)

void	set_source_rgba (const char *str)

template<typename Derived >
void	translate (const Eigen::MatrixBase< Derived > &v)

template<typename Derived >
void	user_to_device (Eigen::MatrixBase< Derived > &v) const

void	user_to_device (Eigen::Matrix< double, 2, 1 > &v) const

Private Attributes
Cairo::RefPtr< Cairo::Context >	m_ctx

Detailed Description

wrapper for cairo context which adds methods allowing for eigen vector typed points

Definition at line 38 of file EigenCairo.h.

Constructor & Destructor Documentation

mpblocks::gtk::EigenCairo::EigenCairo ( const Cairo::RefPtr< Cairo::Context > & ctx )

Member Function Documentation

template<typename Derived >

void mpblocks::gtk::EigenCairo::arc	(	const Eigen::MatrixBase< Derived > &	c,
		double	radius,
		double	angle1,
		double	angle2
	)

Adds a circular arc of the given radius to the current path. The arc is centered at (xc, yc), begins at angle1 and proceeds in the direction of increasing angles to end at angle2. If angle2 is less than angle1 it will be progressively increased by 2*M_PI until it is greater than angle1.

If there is a current point, an initial line segment will be added to the path to connect the current point to the beginning of the arc. If this initial line is undesired, it can be avoided by calling begin_new_sub_path() before calling arc().

Angles are measured in radians. An angle of 0 is in the direction of the positive X axis (in user-space). An angle of M_PI/2.0 radians (90 degrees) is in the direction of the positive Y axis (in user-space). Angles increase in the direction from the positive X axis toward the positive Y axis. So with the default transformation matrix, angles increase in a clockwise direction.

( To convert from degrees to radians, use degrees * (M_PI / 180.0). )

This function gives the arc in the direction of increasing angles; see arc_negative() to get the arc in the direction of decreasing angles.

The arc is circular in user-space. To achieve an elliptical arc, you can scale the current transformation matrix by different amounts in the X and Y directions. For example, to draw an ellipse in the box given by x, y, width, height:

context->save();
context->translate(x, y);
context->scale(width / 2.0, height / 2.0);
context->arc(0.0, 0.0, 1.0, 0.0, 2 * M_PI);
context->restore();

Parameters

xc	X position of the center of the arc
yc	Y position of the center of the arc
radius	the radius of the arc
angle1	the start angle, in radians
angle2	the end angle, in radians

Definition at line 77 of file EigenCairo.hpp.

template<typename Derived >

void mpblocks::gtk::EigenCairo::arc_negative	(	const Eigen::MatrixBase< Derived > &	c,
		double	radius,
		double	angle1,
		double	angle2
	)

Adds a circular arc of the given radius to the current path. The arc is centered at (xc, yc), begins at angle1 and proceeds in the direction of decreasing angles to end at angle2. If angle2 is greater than angle1 it will be progressively decreased by 2*M_PI until it is greater than angle1.

See arc() for more details. This function differs only in the direction of the arc between the two angles.

Parameters

xc	X position of the center of the arc
yc	Y position of the center of the arc
radius	the radius of the arc
angle1	the start angle, in radians
angle2	the end angle, in radians

Definition at line 83 of file EigenCairo.hpp.

template<typename Derived >

void mpblocks::gtk::EigenCairo::circle	(	const Eigen::MatrixBase< Derived > &	c,
		double	r
	)

inline

Definition at line 115 of file EigenCairo.hpp.

template<typename Derived1 , typename Derived2 , typename Derived3 >

void mpblocks::gtk::EigenCairo::curve_to	(	const Eigen::MatrixBase< Derived1 > &	x,
		const Eigen::MatrixBase< Derived2 > &	c1,
		const Eigen::MatrixBase< Derived3 > &	c2
	)

Adds a cubic Bezier spline to the path from the current point to position (x3, y3) in user-space coordinates, using (x1, y1) and (x2, y2) as the control points. After this call the current point will be (x3, y3).

Parameters

x1	the X coordinate of the first control point
y1	the Y coordinate of the first control point
x2	the X coordinate of the second control point
y2	the Y coordinate of the second control point
x3	the X coordinate of the end of the curve
y3	the Y coordinate of the end of the curve

Definition at line 68 of file EigenCairo.hpp.

template<typename Derived >

void mpblocks::gtk::EigenCairo::line_to ( const Eigen::MatrixBase< Derived > & v ) const

Adds a line to the path from the current point to position (x, y) in user-space coordinates. After this call the current point will be (x, y).

Parameters

x	the X coordinate of the end of the new line
y	the Y coordinate of the end of the new line

Definition at line 62 of file EigenCairo.hpp.

template<typename Derived >

void mpblocks::gtk::EigenCairo::move_to ( const Eigen::MatrixBase< Derived > & v ) const

If the current subpath is not empty, begin a new subpath. After this call the current point will be (x, y).

Parameters

x	the X coordinate of the new position
y	the Y coordinate of the new position

Definition at line 56 of file EigenCairo.hpp.

template<typename Derived1 , typename Derived2 >

void mpblocks::gtk::EigenCairo::rectangle	(	const Eigen::MatrixBase< Derived1 > &	x,
		const Eigen::MatrixBase< Derived2 > &	s
	)

Adds a closed-subpath rectangle of the given size to the current path at position (x, y) in user-space coordinates.

This function is logically equivalent to:

context->move_to(x, y);
context->rel_line_to(width, 0);
context->rel_line_to(0, height);
context->rel_line_to(-width, 0);
context->close_path();

Parameters

x	the X coordinate of the top left corner of the rectangle
y	the Y coordinate to the top left corner of the rectangle
width	the width of the rectangle
height	the height of the rectangle

Definition at line 108 of file EigenCairo.hpp.

template<typename Derived1 , typename Derived2 , typename Derived3 >

void mpblocks::gtk::EigenCairo::rel_curve_to	(	const Eigen::MatrixBase< Derived1 > &	dx,
		const Eigen::MatrixBase< Derived2 > &	dc1,
		const Eigen::MatrixBase< Derived3 > &	dc2
	)

Relative-coordinate version of curve_to(). All offsets are relative to the current point. Adds a cubic Bezier spline to the path from the current point to a point offset from the current point by (dx3, dy3), using points offset by (dx1, dy1) and (dx2, dy2) as the control points. After this call the current point will be offset by (dx3, dy3).

Given a current point of (x, y),

rel_curve_to(dx1, dy1, dx2, dy2, dx3, dy3)

is logically equivalent to

curve_to(x + dx1, y + dy1, x + dx2, y + dy2, x + dx3, y + dy3).

Parameters

dx1	the X offset to the first control point
dy1	the Y offset to the first control point
dx2	the X offset to the second control point
dy2	the Y offset to the second control point
dx3	the X offset to the end of the curve
dy3	the Y offset to the end of the curve

It is an error to call this function with no current point. Doing so will cause this to shutdown with a status of CAIRO_STATUS_NO_CURRENT_POINT. Cairomm will then throw an exception.

Definition at line 99 of file EigenCairo.hpp.

template<typename Derived >

void mpblocks::gtk::EigenCairo::rel_line_to ( const Eigen::MatrixBase< Derived > & v )

Relative-coordinate version of line_to(). Adds a line to the path from the current point to a point that is offset from the current point by (dx, dy) in user space. After this call the current point will be offset by (dx, dy).

Given a current point of (x, y),

rel_line_to(dx, dy)

is logically equivalent to

line_to(x + dx, y + dy).

Parameters

dx	the X offset to the end of the new line
dy	the Y offset to the end of the new line

It is an error to call this function with no current point. Doing so will cause this to shutdown with a status of CAIRO_STATUS_NO_CURRENT_POINT. Cairomm will then throw an exception.

Definition at line 94 of file EigenCairo.hpp.

template<typename Derived >

void mpblocks::gtk::EigenCairo::rel_move_to ( const Eigen::MatrixBase< Derived > & v )

If the current subpath is not empty, begin a new subpath. After this call the current point will offset by (x, y).

Given a current point of (x, y),

rel_move_to(dx, dy)

is logically equivalent to

move_to(x + dx, y + dy)

Parameters

dx	the X offset
dy	the Y offset

It is an error to call this function with no current point. Doing so will cause this to shutdown with a status of CAIRO_STATUS_NO_CURRENT_POINT. Cairomm will then throw an exception.

Definition at line 89 of file EigenCairo.hpp.

template<typename Derived >

void mpblocks::gtk::EigenCairo::scale ( const Eigen::MatrixBase< Derived > & v )

Modifies the current transformation matrix (CTM) by scaling the X and Y user-space axes by sx and sy respectively. The scaling of the axes takes place after any existing transformation of user space.

Parameters

sx	scale factor for the X dimension
sy	scale factor for the Y dimension

Definition at line 41 of file EigenCairo.hpp.

void mpblocks::gtk::EigenCairo::set_source ( const Gdk::RGBA & rgba )

Sets the source pattern within the Context to source. This Pattern will then be used for any subsequent drawing operation until a new source pattern is set.

Note: The Pattern's transformation matrix will be locked to the user space in effect at the time of set_source(). This means that further modifications of the current transformation matrix will not affect the source pattern.

Parameters

source a Pattern to be used as the source for subsequent drawing operations.

See Also: Pattern::set_matrix(); set_source_rgb(); set_source_rgba(); set_source(const RefPtr<Surface>& surface, double x, double y)

void mpblocks::gtk::EigenCairo::set_source_rgb ( const char * str )

Sets the source pattern within the Context to an opaque color. This opaque color will then be used for any subsequent drawing operation until a new source pattern is set.

The color components are floating point numbers in the range 0 to 1. If the values passed in are outside that range, they will be clamped.

Parameters

red	red component of color
green	green component of color
blue	blue component of color

See Also: set_source_rgba(); set_source()

void mpblocks::gtk::EigenCairo::set_source_rgba ( const char * str )

Sets the source pattern within the Context to a translucent color. This color will then be used for any subsequent drawing operation until a new source pattern is set.

The color and alpha components are floating point numbers in the range 0 to 1. If the values passed in are outside that range, they will be clamped.

Parameters

red	red component of color
green	green component of color
blue	blue component of color
alpha	alpha component of color

See Also: set_source_rgb(); set_source()

template<typename Derived >

void mpblocks::gtk::EigenCairo::translate ( const Eigen::MatrixBase< Derived > & v )

Modifies the current transformation matrix (CTM) by translating the user-space origin by (tx, ty). This offset is interpreted as a user-space coordinate according to the CTM in place before the new call to cairo_translate. In other words, the translation of the user-space origin takes place after any existing transformation.

Parameters

tx	amount to translate in the X direction
ty	amount to translate in the Y direction

Definition at line 35 of file EigenCairo.hpp.

template<typename Derived >

void mpblocks::gtk::EigenCairo::user_to_device ( Eigen::MatrixBase< Derived > & v ) const

Transform a coordinate from user space to device space by multiplying the given point by the current transformation matrix (CTM).

Parameters

x	X value of coordinate (in/out parameter)
y	Y value of coordinate (in/out parameter)

Definition at line 47 of file EigenCairo.hpp.

void mpblocks::gtk::EigenCairo::user_to_device ( Eigen::Matrix< double, 2, 1 > & v ) const

Member Data Documentation

Cairo::RefPtr<Cairo::Context> mpblocks::gtk::EigenCairo::m_ctx

private

Definition at line 40 of file EigenCairo.h.

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

include/mpblocks/gtk/EigenCairo.h
include/mpblocks/gtk/EigenCairo.hpp

Classes

Public Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation