bnb::transformation Class Reference

#include <transformation.hpp>

Inheritance diagram for bnb::transformation:

Classes
struct	affine_coeffs_t

Public Types
enum class	rotate_t : uint32_t { deg_0 = 0 , deg_90 = 90 , deg_180 = 180 , deg_270 = 270 }
	Rotation is counter clockwise(only in standart basis): More...
using	mat_t = std::array<float, mat_s * mat_s>
	3x3 row-maj transform matrix

Public Member Functions
	transformation ()
	Constructs identity transform.
	transformation (const mat_t &mat)
	Constructs from mat_t.
	transformation (mat_t::const_pointer mat)
	transformation (rotate_t rotate)
	Constructs rotate transformation.
	transformation (float scale_x, float scale_y=1.f, float t_x=0, float t_y=0, rotate_t rotate=rotate_t::deg_0, bool flip_x=false, bool flip_y=false)
	Constructs affine transformation.
	transformation (affine_coeffs_t coeffs)
	Constructs affine transformation.
	transformation (pixel_rect source_rect, pixel_rect target_rect, rotate_t rotate=rotate_t::deg_0, bool flip_x=false, bool flip_y=false)
	Constructs transformation from source to target rectangle Rotation and flips are around rectangles' center.
	transformation (transformation &&t) noexcept
transformation &	operator= (transformation &&t) noexcept
	transformation (const transformation &t)
transformation &	operator= (const transformation &t)
transformation	operator>> (const transformation &t) const noexcept
	Applies transform t after this e.g.
point2d	operator* (const point2d &point) const noexcept
	Apply transform to point.
bool	operator== (const transformation &t) const noexcept
transformation	inverse () const
	Get the inverse of the transformation.
transformation	clone () const noexcept
	Clone the transformation.
mat_t::const_pointer	data () const noexcept
	Pointer to matrix data in memory (row major)
mat_t	get_mat () const noexcept
	Returns 3x3 row-maj transform matrix.
mat_t	transposed_data () const noexcept
	Returns transposed matrix data (column major, opengl)
std::string	to_string () const noexcept
	Cast to string for debug purposes.
bool	is_affine () const noexcept
	Checks if last row is [0, 0, 1] up to float precision.
void	normalize_affine () noexcept
	Normalizes transform to be exactly affine.
std::optional< transformation::affine_coeffs_t >	extract_affine_coeffs () const
	Tries to extract affine coefficients from transformation.
std::shared_ptr< interfaces::transformation >	chain_right (const std::shared_ptr< interfaces::transformation > &t) const override
interfaces::point2d	transform_point (const interfaces::point2d &p) const override
	Apply transform to point.
interfaces::pixel_rect	transform_rect (const interfaces::pixel_rect &rect) const override
bool	equals (const std::shared_ptr< interfaces::transformation > &t) const override
std::shared_ptr< interfaces::transformation >	inverse_j () const override
	Get the inverse of the transformation.
std::shared_ptr< interfaces::transformation >	clone_j () const override
	Clone the transformation.
std::vector< float >	get_mat_j () const override
	Returns 3x3 row-maj transform matrix.
Public Member Functions inherited from bnb::interfaces::transformation
virtual std::shared_ptr< transformation >	chain_right (const std::shared_ptr< transformation > &t) const =0
	Applies transform t after this e.g.
virtual bool	equals (const std::shared_ptr< transformation > &t) const =0

Static Public Member Functions
static const transformation &	get_flip_instance (bool flip_x, bool flip_y)
	Get reference to static flip-only transform.
Static Public Member Functions inherited from bnb::interfaces::transformation
static std::shared_ptr< transformation >	make_identity ()
	Constructs identity transform.
static std::shared_ptr< transformation >	make_data (const std::vector< float > &mat)
	Constructs from mat_t.
static std::shared_ptr< transformation >	make_rot (rotation rot)
	Constructs rotate transformation.
static std::shared_ptr< transformation >	make_affine (float scale_x, float scale_y, float t_x, float t_y, rotation rot, bool flip_x, bool flip_y)
	Constructs affine transformation.
static std::shared_ptr< transformation >	make_rects (const pixel_rect &source_rect, const pixel_rect &target_rect, rotation rot, bool flip_x, bool flip_y)
	Constructs transformation from source to target rectangle Rotation and flips are around rectangles' center.

Static Public Attributes
static const int	mat_s = 3

Detailed Description

This class implements affine or perspective 2d transformations Standard usage implies transformation from common basis into other(common, image or standard) basis (e.g. written as (common -> image) in documentation)

Frequently used basises are: <f ^f >f vf: direction of face-up vector left, up, right, down

standard basis: ^ y | ^f .--> x

common basis = image(buffer) basis: .--> x | ^f v y

Definition at line 58 of file transformation.hpp.

Member Typedef Documentation

mat_t

using bnb::transformation::mat_t = std::array<float, mat_s * mat_s>

3x3 row-maj transform matrix

Definition at line 64 of file transformation.hpp.

Member Enumeration Documentation

rotate_t

enum class bnb::transformation::rotate_t : uint32_t

strong

Rotation is counter clockwise(only in standart basis):

• Rotating vector(1,0) (= x basis vector) by 90deg results in vector(0,1) (= y basis vector)
• In image buffer basis(y points down) the rotation would go clockwise

Definition at line 70 of file transformation.hpp.

        {
            deg_0 = 0,
            deg_90 = 90,
            deg_180 = 180,
            deg_270 = 270
        };

Constructor & Destructor Documentation

~transformation()

bnb::transformation::~transformation ( )

virtual

Reimplemented from bnb::interfaces::transformation.

Member Function Documentation

chain_right()

std::shared_ptr< interfaces::transformation > bnb::transformation::chain_right ( const std::shared_ptr< interfaces::transformation > & t ) const

inlineoverride

Definition at line 161 of file transformation.hpp.

        {
            return std::make_shared<transformation>(*this >> static_cast<transformation&>(*t));
        }

clone_j()

std::shared_ptr< interfaces::transformation > bnb::transformation::clone_j ( ) const

inlineoverridevirtual

Clone the transformation.

Implements bnb::interfaces::transformation.

Definition at line 175 of file transformation.hpp.

        {
            return std::make_shared<transformation>(clone());
        }

equals()

bool bnb::transformation::equals ( const std::shared_ptr< interfaces::transformation > & t ) const

inlineoverride

Definition at line 167 of file transformation.hpp.

        {
            return *this == static_cast<transformation&>(*t);
        }

get_mat_j()

std::vector< float > bnb::transformation::get_mat_j ( ) const

inlineoverridevirtual

Returns 3x3 row-maj transform matrix.

Implements bnb::interfaces::transformation.

Definition at line 179 of file transformation.hpp.

        {
            auto m = get_mat();
            return {m.begin(), m.end()};
        }

inverse()

transformation bnb::transformation::inverse

(

)

const

Get the inverse of the transformation.

Exceptions

std::logic_error

when matrix is singular

inverse_j()

std::shared_ptr< interfaces::transformation > bnb::transformation::inverse_j ( ) const

inlineoverridevirtual

Get the inverse of the transformation.

Exceptions

std::logic_error

when matrix is singular

Implements bnb::interfaces::transformation.

Definition at line 171 of file transformation.hpp.

        {
            return std::make_shared<transformation>(inverse());
        }

normalize_affine()

void bnb::transformation::normalize_affine ( )

noexcept

Normalizes transform to be exactly affine.

Results are invalid in case last row is not [~0, ~0, C]

operator>>()

transformation bnb::transformation::operator>> ( const transformation & t ) const

noexcept

Applies transform t after this e.g.

{rotate >> translate;} rotates first: (initial -> rotated) >> (rotated -> translated) = (initial -> translated)

Member Data Documentation

mat_s

const int bnb::transformation::mat_s = 3

static

Definition at line 61 of file transformation.hpp.

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

• /Users/itumashyk/Workspace/banuba_sdk/libs/types/bnb/types/transformation.hpp