fbg_opengl_es2.h File Reference

#include <sys/ioctl.h>
#include <linux/fb.h>
#include <unistd.h>
#include <fcntl.h>
#include <GLES2/gl2.h>
#include <EGL/egl.h>
#include <EGL/eglext.h>
#include "fbgraphics.h"

Go to the source code of this file.

Data Structures
struct	_fbg_gles2_context
	OpenGL ES 2.0 wrapper data structure. More...
struct	_fbg_vbo_data
	struct which hold usual VBO data for 3D objects More...

Functions
struct _fbg *	fbg_gles2Setup (const char *fb_device, int components)
	initialize a FB Graphics OpenGL ES 2 (fbdev or RPI direct) context More...
void	fbg_gles2Clear ()
	OpenGL clear. More...
void	fbg_gles2UpdateBuffer (struct _fbg *fbg)
	this update FBG disp_buffer with the actual rendered OpenGL content More...
int	fbg_gles2ShouldClose (struct _fbg *fbg)
	Query the user requested (window close etc) close status. More...
GLuint	fbg_gles2CreateTextureFromImage (struct _fbg *fbg, struct _fbg_img *img)
	create a non-interpolated (NEAREST) GL texture from a FBG image More...
GLuint	fbg_gles2CreateTexture (GLuint width, GLuint height, GLint internal_format)
	create an empty non-interpolated (NEAREST) GL texture More...
struct _fbg_vbo_data *	fbg_gles2CreateVBO (GLsizeiptr indices_count, const GLvoid *indices_data, size_t sizeof_indice_type, GLsizeiptr vertices_count, const GLvoid *vertices_data, GLsizeiptr texcoords_count, const GLvoid *texcoords_data, GLsizeiptr normals_count, const GLvoid *normals_data, GLsizeiptr colors_count, const GLvoid *colors_data)
	create a VBO from indexed data, support for vertices, UVs, normals and colors More...
void	fbg_gles2FreeVBOData (struct _fbg_vbo_data *vbo_data)
	free VBO data (created with fbg_gles2CreateVBO) More...
GLuint	fbg_gles2CreateVBOvu (GLsizeiptr data_count, const GLvoid *data)
	create a VBO from vertices + UV data packed into a single array More...
GLuint	fbg_gles2CreateShader (GLenum type, const GLchar *source)
	create a FBO More...
GLuint	fbg_gles2CreateShaderFromFile (GLenum type, const char *filename)
	create a shader from the content of a file More...
GLuint	fbg_gles2CreateProgram (GLuint vertex_shader, GLuint fragment_shader)
	create a vertex and/or fragment program More...
GLenum	fbg_gles2CreateProgramFromFiles (const char *vs, const char *fs)
	create a vertex and/or fragment/geometry program from a file More...
GLenum	fbg_gles2CreateProgramFromString (const char *vs, const char *fs)
	create a vertex and/or fragment/geometry program from a string More...

Variables
const GLfloat	fbg_gles2Quad []
	Simple quad geometry (vertices + UV) More...
const char *	fbg_gles2SimpleVs
	Simple vertex shader (screen quad, vertices + UV) More...
const char *	fbg_gles2SimpleFs
	Simple textured fragment shader. More...

---

Data Structure Documentation

_fbg_gles2_context

struct _fbg_gles2_context

OpenGL ES 2.0 wrapper data structure.

Definition at line 47 of file fbg_opengl_es2.h.

Data Fields
EGLContext	egl_context	EGL context.
EGLDisplay	egl_display	EGL display.
void *	egl_image	EGL image.
EGLContext	egl_surface	EGL surface.
GLuint	fbg_texture	FBG texture (updated at each frames)
GLuint	fbg_vbo	FBG VBO.
int	fd	Framebuffer file descriptor.
GLenum	simple_program	Simple GLSL program (screen-aligned textured quad)
int	update_buffer	tell wether fbg_gles2 should update fbg disp_buffer after rendering
struct fb_var_screeninfo	vinfo	Framebuffer device var. informations.

_fbg_vbo_data

struct _fbg_vbo_data

struct which hold usual VBO data for 3D objects

Definition at line 73 of file fbg_opengl_es2.h.

Data Fields
GLuint	cbo
GLuint	ibo
GLuint	nbo
GLuint	tbo
GLuint	vbo

Function Documentation

fbg_gles2Clear()

void fbg_gles2Clear

(

)

OpenGL clear.

fbg_gles2CreateProgram()

GLuint fbg_gles2CreateProgram	(	GLuint	vertex_shader,
		GLuint	fragment_shader
	)

create a vertex and/or fragment program

Parameters

vertex_shader	vertex shader id, can be 0
fragment_shader	fragment shader id, can be 0

Returns

GL shader id

fbg_gles2CreateProgramFromFiles()

GLenum fbg_gles2CreateProgramFromFiles	(	const char *	vs,
		const char *	fs
	)

create a vertex and/or fragment/geometry program from a file

Parameters

vs	vertex shader file
fs	fragment shader file

Returns

GL shader id

fbg_gles2CreateProgramFromString()

GLenum fbg_gles2CreateProgramFromString	(	const char *	vs,
		const char *	fs
	)

create a vertex and/or fragment/geometry program from a string

Parameters

vs	vertex shader string
fs	fragment shader string

Returns

GL shader id

fbg_gles2CreateShader()

GLuint fbg_gles2CreateShader	(	GLenum	type,
		const GLchar *	source
	)

create a FBO

Parameters

texture

GL texture id

Returns

GL FBO idcreate a single shader

Parameters

type	GL shader type
source	shader code

Returns

GL shader id

fbg_gles2CreateShaderFromFile()

GLuint fbg_gles2CreateShaderFromFile	(	GLenum	type,
		const char *	filename
	)

create a shader from the content of a file

Parameters

type	GL shader type
filename	file to load

Returns

GL shader id

fbg_gles2CreateTexture()

GLuint fbg_gles2CreateTexture	(	GLuint	width,
		GLuint	height,
		GLint	internal_format
	)

create an empty non-interpolated (NEAREST) GL texture

Parameters

width	width of the requested texture
height	height of the requested texture
internal_format	OpenGL format (GL_RGBA etc.)

Returns

GL texture id

fbg_gles2CreateTextureFromImage()

GLuint fbg_gles2CreateTextureFromImage	(	struct _fbg *	fbg,
		struct _fbg_img *	img
	)

create a non-interpolated (NEAREST) GL texture from a FBG image

Parameters

fbg	pointer to a FBG context / data structure
img	image structure pointer

Returns

GL texture id

fbg_gles2CreateVBO()

struct _fbg_vbo_data* fbg_gles2CreateVBO	(	GLsizeiptr	indices_count,
		const GLvoid *	indices_data,
		size_t	sizeof_indice_type,
		GLsizeiptr	vertices_count,
		const GLvoid *	vertices_data,
		GLsizeiptr	texcoords_count,
		const GLvoid *	texcoords_data,
		GLsizeiptr	normals_count,
		const GLvoid *	normals_data,
		GLsizeiptr	colors_count,
		const GLvoid *	colors_data
	)

create a VBO from indexed data, support for vertices, UVs, normals and colors

Parameters

indices_count	indices count
indices_data	data containing indices
sizeof_indice_type	sizeof indice type
vertices_count	vertices count
vertices_data	data containing vertices
texcoords_count	uv count
texcoords_data	data containing uv
normals_count	normals count
normals_data	data containing normals
colors_count	colors count
colors_data	data containing colors

Returns

_fbg_vbo_data data structure containing the VBOs

fbg_gles2CreateVBOvu()

GLuint fbg_gles2CreateVBOvu	(	GLsizeiptr	data_count,
		const GLvoid *	data
	)

create a VBO from vertices + UV data packed into a single array

Parameters

data_count	vertices data count
data	data containing all vertices (set of 3 x float) then all associated UVs (set of 2 x float)

Returns

GL VBO id

fbg_gles2FreeVBOData()

void fbg_gles2FreeVBOData

(

struct _fbg_vbo_data *

vbo_data

)

free VBO data (created with fbg_gles2CreateVBO)

Parameters

vbo_data

data structure containing the VBOs

fbg_gles2Setup()

struct _fbg* fbg_gles2Setup	(	const char *	fb_device,
		int	components
	)

initialize a FB Graphics OpenGL ES 2 (fbdev or RPI direct) context

Parameters

fb_device	framebuffer device; example : /dev/fb0
components	fbg context color components (4 for RGBA or 3 for RGB)

Returns

FBG data structure pointer

fbg_gles2ShouldClose()

int fbg_gles2ShouldClose

(

struct _fbg *

fbg

)

Query the user requested (window close etc) close status.

Parameters

fbg	pointer to a FBG context / data structure

Returns

Boolean indicating close status

fbg_gles2UpdateBuffer()

void fbg_gles2UpdateBuffer

(

struct _fbg *

fbg

)

this update FBG disp_buffer with the actual rendered OpenGL content

Parameters

fbg	pointer to a FBG context / data structure

Variable Documentation

fbg_gles2Quad

const GLfloat fbg_gles2Quad[]

Simple quad geometry (vertices + UV)

fbg_gles2SimpleFs

const char* fbg_gles2SimpleFs

Simple textured fragment shader.

fbg_gles2SimpleVs

const char* fbg_gles2SimpleVs

Simple vertex shader (screen quad, vertices + UV)