lxgui::gui::gl::material Class Reference

A class that holds rendering data This implementation can contain either a plain color or a real OpenGL texture. It is also used by the gui::gl::render_target class to store the output data. More...

#include <gui_gl_material.hpp>

Inheritance diagram for lxgui::gui::gl::material:

Public Types
enum class	wrap { repeat , clamp }
enum class	filter { none , linear }

Public Member Functions
	material (const vector2ui &dimensions, wrap wrp=wrap::repeat, filter filt=filter::none)
	Constructor for textures.
	material (std::uint32_t texture_handle, const vector2ui &canvas_dimensions, const bounds2f rect, filter filt=filter::none)
	Constructor for atlas textures.
	material (const material &tex)=delete
	material (material &&tex)=delete
material &	operator= (const material &tex)=delete
material &	operator= (material &&tex)=delete
	~material () override
	Destructor.
bounds2f	get_rect () const override
	Returns the pixel rect in pixels of the canvas containing this texture (if any).
vector2ui	get_canvas_dimensions () const override
	Returns the physical dimensions (in pixels) of the canvas containing this texture (if any).
bool	uses_same_texture (const gui::material &other) const override
	Checks if another material is based on the same texture as the current material.
bool	set_dimensions (const vector2ui &dimensions)
	Resizes this texture.
void	set_wrap (wrap wrp)
	Sets the wrap mode of this texture.
void	set_filter (filter filt)
	Sets the filter mode of this texture.
filter	get_filter () const
	Returns the filter mode of this texture.
void	bind () const
	Sets this material as the active one.
void	update_texture (const color32 *data)
	Updates the texture that is in GPU memory.
std::uint32_t	get_handle () const
	Returns the OpenGL texture handle.
vector2f	get_canvas_uv (const vector2f &texture_uv, bool from_normalized) const
	Returns normalized UV coordinates on the canvas, given local UV coordinates.
vector2f	get_local_uv (const vector2f &canvas_uv, bool as_normalized) const
	Returns local UV coordinates on the texture, given canvas UV coordinates.
bool	is_in_atlas () const
	Checks if the material is embedded in an atlas.

Static Public Member Functions
static void	premultiply_alpha (std::vector< color32 > &data)
	Premultiplies the texture by alpha component.
static void	check_availability ()
	Checks if the machine is capable of using some features.
static std::size_t	get_max_size ()
	Returns the maximum size available for a texture, in pixels.

Protected Attributes
bool	is_atlas_ = false

Detailed Description

A class that holds rendering data This implementation can contain either a plain color or a real OpenGL texture. It is also used by the gui::gl::render_target class to store the output data.

Definition at line 21 of file gui_gl_material.hpp.

Member Enumeration Documentation

filter

enum class lxgui::gui::material::filter

stronginherited

Enumerator
none
linear

Definition at line 20 of file gui_material.hpp.

wrap

enum class lxgui::gui::material::wrap

stronginherited

Enumerator
repeat
clamp

Definition at line 18 of file gui_material.hpp.

Constructor & Destructor Documentation

material() [1/4]

lxgui::gui::gl::material::material	(	const vector2ui &	dimensions,
		wrap	wrp = wrap::repeat,
		filter	filt = filter::none
	)

Constructor for textures.

Parameters

dimensions	The requested texture dimensions
wrp	How to adjust texture coordinates that are outside the [0,1] range
filt	Use texture filtering or not (see set_filter())

material() [2/4]

lxgui::gui::gl::material::material	(	std::uint32_t	texture_handle,
		const vector2ui &	canvas_dimensions,
		const bounds2f	rect,
		filter	filt = filter::none
	)

Constructor for atlas textures.

Parameters

texture_handle	The handle to the texture object of the atlas
canvas_dimensions	The dimensions of the texture atlas
rect	The position of this texture inside the atlas
filt	Use texture filtering or not (see set_filter())

material() [3/4]

lxgui::gui::gl::material::material ( const material &  tex )

delete

material() [4/4]

lxgui::gui::gl::material::material ( material &&  tex )

delete

~material()

lxgui::gui::gl::material::~material ( )

overridevirtual

Destructor.

Reimplemented from lxgui::gui::material.

Member Function Documentation

bind()

void lxgui::gui::gl::material::bind

(

)

const

Sets this material as the active one.

check_availability()

static void lxgui::gui::gl::material::check_availability ( )

static

Checks if the machine is capable of using some features.

Note

The function checks for non power of two capability. If the graphics card doesn't support it, the material class will automatically create power of two textures.

get_canvas_dimensions()

vector2ui lxgui::gui::gl::material::get_canvas_dimensions ( ) const

overridevirtual

Returns the physical dimensions (in pixels) of the canvas containing this texture (if any).

Returns

The physical dimensions (in pixels) of the canvas containing this (if any)

Note

When a texture is loaded, most of the time it will fill the entire "canvas", namely, the 2D pixel array containing the texture data. However, some old hardware don't support textures that have non power-of-two dimensions. If the user creates a material for such a texture, the gui::renderer will create a bigger canvas that has power-of-two dimensions, and store the texture in it. Likewise, if a texture is placed in a wider texture atlas, the canvas will contain more than one texture.

Implements lxgui::gui::material.

get_canvas_uv()

vector2f lxgui::gui::material::get_canvas_uv ( const vector2f &  texture_uv, bool  from_normalized  ) const

inherited

Returns normalized UV coordinates on the canvas, given local UV coordinates.

Parameters

texture_uv	The original UV coordinates, local to this texture
from_normalized	Set to 'true' if input coordinates are normalized

Note

Normalized coordinates range from 0 to 1, with 1 corresponding to the width/height of the texture, while non-normalized coordinates are in pixels.

Definition at line 7 of file gui_material.cpp.

get_filter()

filter lxgui::gui::gl::material::get_filter

(

)

const

Returns the filter mode of this texture.

Returns

The filter mode of this texture

get_handle()

std::uint32_t lxgui::gui::gl::material::get_handle

(

)

const

Returns the OpenGL texture handle.

Note

For internal use.

get_local_uv()

vector2f lxgui::gui::material::get_local_uv ( const vector2f &  canvas_uv, bool  as_normalized  ) const

inherited

Returns local UV coordinates on the texture, given canvas UV coordinates.

Parameters

canvas_uv	The canvas UV coordinates
as_normalized	Set to 'true' if output coordinates should be normalized

Note

Normalized coordinates range from 0 to 1, with 1 corresponding to the width/height of the texture, while non-normalized coordinates are in pixels.

Definition at line 20 of file gui_material.cpp.

get_max_size()

static std::size_t lxgui::gui::gl::material::get_max_size ( )

static

Returns the maximum size available for a texture, in pixels.

Returns

The maximum size available for a texture, in pixels

get_rect()

bounds2f lxgui::gui::gl::material::get_rect ( ) const

overridevirtual

Returns the pixel rect in pixels of the canvas containing this texture (if any).

Returns

The pixel rect in pixels of the canvas containing this texture (if any)

Implements lxgui::gui::material.

is_in_atlas()

bool lxgui::gui::material::is_in_atlas ( ) const

inherited

Checks if the material is embedded in an atlas.

Returns

'true' if the material is inside an atlas, 'false' otherwise.

Definition at line 33 of file gui_material.cpp.

operator=() [1/2]

material & lxgui::gui::gl::material::operator= ( const material &  tex )

delete

operator=() [2/2]

material & lxgui::gui::gl::material::operator= ( material &&  tex )

delete

premultiply_alpha()

static void lxgui::gui::gl::material::premultiply_alpha ( std::vector< color32 > &  data )

static

Premultiplies the texture by alpha component.

Parameters

data	The pixel data to pre-multiply

Note

Premultiplied alpha is a rendering technique that allows perfect alpha blending when using render targets.

set_dimensions()

bool lxgui::gui::gl::material::set_dimensions

(

const vector2ui &

dimensions

)

Resizes this texture.

Parameters

dimensions

The new texture dimensions

Returns

'true' if the function had to re-create a new texture object

Note

All the previous data that was stored in this texture will be lost.

set_filter()

void lxgui::gui::gl::material::set_filter

(

filter

filt

)

Sets the filter mode of this texture.

Parameters

filt	Use texture filtering or not

Note

When texture filtering is disabled, enlarged textures get pixelated. Else, the GPU uses an averaging algorithm to blur the pixels.

set_wrap()

void lxgui::gui::gl::material::set_wrap

(

wrap

wrp

)

Sets the wrap mode of this texture.

Parameters

wrp	How to adjust texture coordinates that are outside the [0,1] range

update_texture()

void lxgui::gui::gl::material::update_texture

(

const color32 *

data

)

Updates the texture that is in GPU memory.

Parameters

data	The new pixel data

uses_same_texture()

bool lxgui::gui::gl::material::uses_same_texture ( const gui::material &  other ) const

overridevirtual

Checks if another material is based on the same texture as the current material.

Returns

'true' if both materials use the same texture, 'false' otherwise

Implements lxgui::gui::material.

Member Data Documentation

is_atlas_

bool lxgui::gui::material::is_atlas_ = false

protectedinherited

Definition at line 93 of file gui_material.hpp.

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

• /home/runner/work/lxgui/lxgui/include/lxgui/impl/gui_gl_material.hpp