lmgl::ui::Canvas Class Reference

Canvas for rendering 2D UI elements. More...

#include <canvas.hpp>

Public Member Functions
	Canvas (int width=1920, int height=1080)
	Constructor for Canvas.
	~Canvas ()=default
	Destructor for Canvas.
void	resize (int width, int height)
	Resize the canvas to match window dimensions.
void	add_element (std::shared_ptr< UIElement > element)
	Add a UI element to the canvas.
void	remove_element (std::shared_ptr< UIElement > element)
	Remove a UI element from the canvas.
const std::vector< std::shared_ptr< UIElement > > &	get_elements () const
	Get all UI elements in the canvas.
void	render ()
	Render all UI elements.
const glm::mat4 &	get_projection_matrix () const
	Get the orthographic projection matrix.
int	get_width () const
	Get the canvas width.
int	get_height () const
	Get the canvas height.
void	set_visible (bool visible)
	Set visibility of the entire canvas.
bool	is_visible () const
	Check if the canvas is visible.

Detailed Description

Canvas for rendering 2D UI elements.

The Canvas class provides a 2D rendering surface that sits on top of the 3D world. It manages orthographic projection, automatic window resizing, blending for transparency, and proper render ordering of UI elements.

Constructor & Destructor Documentation

Canvas()

lmgl::ui::Canvas::Canvas	(	int	width = 1920,
		int	height = 1080 )

Constructor for Canvas.

Parameters

width	Initial width of the canvas in pixels.
height	Initial height of the canvas in pixels.

Member Function Documentation

add_element()

void lmgl::ui::Canvas::add_element

(

std::shared_ptr< UIElement >

element

)

Add a UI element to the canvas.

Parameters

element

Shared pointer to the UI element.

get_elements()

const std::vector< std::shared_ptr< UIElement > > & lmgl::ui::Canvas::get_elements ( ) const

inline

Get all UI elements in the canvas.

Returns

Vector of shared pointers to UI elements.

get_height()

int lmgl::ui::Canvas::get_height ( ) const

inline

Get the canvas height.

Returns

Height in pixels.

get_projection_matrix()

const glm::mat4 & lmgl::ui::Canvas::get_projection_matrix ( ) const

inline

Get the orthographic projection matrix.

Maps pixels (0, 0) to (width, height) to normalized device coordinates (-1, -1) to (1, 1).

Returns

Orthographic projection matrix.

get_width()

int lmgl::ui::Canvas::get_width ( ) const

inline

Get the canvas width.

Returns

Width in pixels.

is_visible()

bool lmgl::ui::Canvas::is_visible ( ) const

inline

Check if the canvas is visible.

Returns

True if visible, false otherwise.

remove_element()

void lmgl::ui::Canvas::remove_element

(

std::shared_ptr< UIElement >

element

)

Remove a UI element from the canvas.

Parameters

element

Shared pointer to the UI element.

render()

void lmgl::ui::Canvas::render

(

)

Render all UI elements.

Enables blending, sets up orthographic projection, and renders all UI elements in back-to-front order based on their render order.

resize()

void lmgl::ui::Canvas::resize	(	int	width,
		int	height )

Resize the canvas to match window dimensions.

Updates the orthographic projection matrix to match the new dimensions.

Parameters

width	New width in pixels.
height	New height in pixels.

set_visible()

void lmgl::ui::Canvas::set_visible ( bool visible )

inline

Set visibility of the entire canvas.

Parameters

visible

True to show, false to hide.

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

• include/lmgl/ui/canvas.hpp
• src/ui/canvas.cpp