tgui::Transform Class Reference

Defines a transform matrix. More...

#include <TGUI/Transform.hpp>

Public Member Functions
	Transform ()
	Default constructor.
	Transform (float a00, float a01, float a02, float a10, float a11, float a12, float a20, float a21, float a22)
	Construct a transform from a 3x3 matrix.
	Transform (const std::array< float, 16 > &matrix)
	Constructs a transform from a 4x4 matrix.
const std::array< float, 16 > &	getMatrix () const
	Return the transform as a 4x4 matrix.
Transform	getInverse () const
	Return the inverse of the transform.
Vector2f	transformPoint (const Vector2f &point) const
	Transform a 2D point.
FloatRect	transformRect (const FloatRect &rectangle) const
	Transform a rectangle.
Transform &	combine (const Transform &other)
	Combine the current transform with another one.
Transform &	translate (const Vector2f &offset)
	Combine the current transform with a translation.
Transform &	rotate (float angle, const Vector2f &center={0, 0})
	Combine the current transform with a rotation.
Transform &	scale (const Vector2f &factors, const Vector2f &center={0, 0})
	Combine the current transform with a scaling.
Transform	operator* (const Transform &right) const
	Overload of binary operator * to combine two transforms.
Transform &	operator*= (const Transform &right)
Vector2f	operator* (const Vector2f &right) const
void	roundPosition (float pixelScaleX, float pixelScaleY)
	Rounds the position stored in the transform to the nearest pixel.
void	roundPosition (Vector2f pixelScale)
	Rounds the position stored in the transform to the nearest pixel.

Detailed Description

Defines a transform matrix.

Constructor & Destructor Documentation

Transform() [1/3]

tgui::Transform::Transform

(

)

Default constructor.

Creates an identity transform (a transform that does nothing).

Transform() [2/3]

tgui::Transform::Transform	(	float	a00,
		float	a01,
		float	a02,
		float	a10,
		float	a11,
		float	a12,
		float	a20,
		float	a21,
		float	a22 )

Construct a transform from a 3x3 matrix.

Parameters

a00	Element (0, 0) of the 3x3 matrix
a01	Element (0, 1) of the 3x3 matrix
a02	Element (0, 2) of the 3x3 matrix
a10	Element (1, 0) of the 3x3 matrix
a11	Element (1, 1) of the 3x3 matrix
a12	Element (1, 2) of the 3x3 matrix
a20	Element (2, 0) of the 3x3 matrix
a21	Element (2, 1) of the 3x3 matrix
a22	Element (2, 2) of the 3x3 matrix

Transform() [3/3]

tgui::Transform::Transform

(

const std::array< float, 16 > &

matrix

)

Constructs a transform from a 4x4 matrix.

Parameters

matrix

4x4 transform matrix, similar to what getMatrix returns

Member Function Documentation

combine()

Transform & tgui::Transform::combine

(

const Transform &

other

)

Combine the current transform with another one.

The result is a transform that is equivalent to applying the other transform followed by this transform. Mathematically, it is equivalent to a matrix multiplication (*this) * other.

Parameters

other

Transform to combine with this transform

Returns

Reference to *this

getInverse()

Transform tgui::Transform::getInverse ( ) const

nodiscard

Return the inverse of the transform.

Returns

A new transform which is the inverse of this transform

If the inverse cannot be computed, an identity transform is returned.

getMatrix()

const std::array< float, 16 > & tgui::Transform::getMatrix ( ) const

nodiscard

Return the transform as a 4x4 matrix.

This function returns an array of 16 floats containing the transform elements as a 4x4 matrix, which is directly compatible with OpenGL functions.

glLoadMatrixf(transform.getMatrix().data());

Returns

4x4 transform matrix

operator*()

Transform tgui::Transform::operator* ( const Transform & right ) const

nodiscard

Overload of binary operator * to combine two transforms.

Parameters

right

Transform to combine with a copy of this transform

See also

combine

rotate()

Transform & tgui::Transform::rotate	(	float	angle,
		const Vector2f &	center = {0, 0} )

Combine the current transform with a rotation.

The center of rotation is provided for convenience as a second argument, so that you can build rotations around arbitrary points more easily (and efficiently) than the usual translate(-center).rotate(angle).translate(center).

Parameters

angle	Rotation angle, in degrees
center	Center of rotation

Returns

Reference to *this

roundPosition() [1/2]

void tgui::Transform::roundPosition	(	float	pixelScaleX,
		float	pixelScaleY )

Rounds the position stored in the transform to the nearest pixel.

Parameters

pixelScaleX	Pixels per point horizontally
pixelScaleY	Pixels per point vertically

roundPosition() [2/2]

void tgui::Transform::roundPosition

(

Vector2f

pixelScale

)

Rounds the position stored in the transform to the nearest pixel.

Parameters

pixelScale

Pixels per point, both horizontally and vertically

scale()

Transform & tgui::Transform::scale	(	const Vector2f &	factors,
		const Vector2f &	center = {0, 0} )

Combine the current transform with a scaling.

The center of scaling is provided for convenience as a second argument, so that you can build scaling around arbitrary points more easily (and efficiently) than the usual translate(-center).scale(factors).translate(center).

Parameters

factors	Scaling factors
center	Center of scaling

Returns

Reference to *this

transformPoint()

Vector2f tgui::Transform::transformPoint ( const Vector2f & point ) const

nodiscard

Transform a 2D point.

Parameters

point

Point to transform

Returns

Transformed point

transformRect()

FloatRect tgui::Transform::transformRect ( const FloatRect & rectangle ) const

nodiscard

Transform a rectangle.

If the transform contains a rotation, the bounding rectangle of the transformed rectangle is returned.

Parameters

rectangle

Rectangle to transform

Returns

Transformed rectangle

translate()

Transform & tgui::Transform::translate

(

const Vector2f &

offset

)

Combine the current transform with a translation.

Parameters

offset

Translation offset to apply

Returns

Reference to *this

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

• include/TGUI/Transform.hpp