lxgui::gui::gl::vertex_cache Class Reference

An object representing cached vertex data on the GPU. More...

#include <gui_gl_vertex_cache.hpp>

Inheritance diagram for lxgui::gui::gl::vertex_cache:

Public Types
enum class	type { triangles , quads }
	The type of vertex data contained in a vertex_cache. More...

Public Member Functions
	vertex_cache (type t)
	Constructor. More...
	~vertex_cache () override
	Destructor. More...
void	update_data (const vertex *vertex_data, std::size_t num_vertex)
	Update the data stored in the cache, reusing existing indices. More...
void	update_indices (const std::uint32_t *vertex_indices, std::size_t num_indices)
	Update the indices stored in the cache, reusing existing data. More...
void	update_indices_if_grow (const std::uint32_t *vertex_indices, std::size_t num_indices)
	Update the indices stored in the cache, but only if the current index cache is smaller. More...
void	update (const vertex *vertex_data, std::size_t num_vertex) override
	Update the data stored in the cache to form new triangles. More...
void	render () const
	Renders the cache. More...
std::size_t	get_vertex_count () const
	Returns the number of vertices stored in this cache. More...

Protected Attributes
type	type_ = type::triangles
std::size_t	num_vertex_ = 0

Detailed Description

An object representing cached vertex data on the GPU.

A vertex cache stores vertices and indices that can be used to draw any shape on the screen. If the type is TRIANGLES, each group of 3 vertices forms a triangle, while if the type is QUADS, each group of 4 vertices forms a quad.

Using this class enables more efficient rendering of large groups of sprites or quads that share the same material (texture). This is especially true if the data to render does not change often.

A vertex cache can be rendered with gui::renderer::render_vertex_cache().

Note

This is an abstract class that must be inherited from and created by the corresponding gui::renderer.

Definition at line 28 of file gui_gl_vertex_cache.hpp.

Member Enumeration Documentation

type

enum lxgui::gui::vertex_cache::type

stronginherited

The type of vertex data contained in a vertex_cache.

Enumerator
triangles
quads	3 vertices per element 4 vertices per element

Definition at line 32 of file gui_vertex_cache.hpp.

Constructor & Destructor Documentation

vertex_cache()

lxgui::gui::gl::vertex_cache::vertex_cache ( type  t )

explicit

Constructor.

Parameters

t	The type of data this cache will hold

A default constructed vertex cache holds no data. Use update() to store vertices to be rendered. The size hint can enable the cache to be pre-allocated, which will avoid a reallocation when update() is called.

~vertex_cache()

lxgui::gui::gl::vertex_cache::~vertex_cache ( )

overridevirtual

Destructor.

Reimplemented from lxgui::gui::vertex_cache.

Member Function Documentation

get_vertex_count()

std::size_t lxgui::gui::vertex_cache::get_vertex_count ( ) const

inlineinherited

Returns the number of vertices stored in this cache.

Returns

The number of vertices stored in this cache

Definition at line 73 of file gui_vertex_cache.hpp.

render()

void lxgui::gui::gl::vertex_cache::render

(

)

const

Renders the cache.

Note

This does not bind the material, just binds the cache and renders it with whatever shader / texture is currently bound.

update()

void lxgui::gui::gl::vertex_cache::update ( const vertex *  vertex_data, std::size_t  num_vertex  )

overridevirtual

Update the data stored in the cache to form new triangles.

Parameters

vertex_data	The vertices to cache
num_vertex	The number of vertices to cache

Note

If the type if TRIANGLES, num_vertex must be a multiple of 3. If the type if QUADS, num_vertex must be a multiple of 4.

Implements lxgui::gui::vertex_cache.

update_data()

void lxgui::gui::gl::vertex_cache::update_data	(	const vertex *	vertex_data,
		std::size_t	num_vertex
	)

Update the data stored in the cache, reusing existing indices.

Parameters

vertex_data	The vertices to cache
num_vertex	The number of vertices to cache

update_indices()

void lxgui::gui::gl::vertex_cache::update_indices	(	const std::uint32_t *	vertex_indices,
		std::size_t	num_indices
	)

Update the indices stored in the cache, reusing existing data.

Parameters

vertex_indices	The indices to use for drawing triangles
num_indices	The number of indices to cache

update_indices_if_grow()

void lxgui::gui::gl::vertex_cache::update_indices_if_grow	(	const std::uint32_t *	vertex_indices,
		std::size_t	num_indices
	)

Update the indices stored in the cache, but only if the current index cache is smaller.

Parameters

vertex_indices	The indices to use for drawing triangles
num_indices	The number of indices to cache

Note

This function assumes that the index buffer is always initialised with valid indices, and that only the number of indices changes. Indices that were set in previous calls of update_indices() are assumed to not change value.

Member Data Documentation

num_vertex_

std::size_t lxgui::gui::vertex_cache::num_vertex_ = 0

protectedinherited

Definition at line 79 of file gui_vertex_cache.hpp.

type_

type lxgui::gui::vertex_cache::type_ = type::triangles

protectedinherited

Definition at line 78 of file gui_vertex_cache.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_vertex_cache.hpp