lg_obj_parser.c File Reference

Functions
LG_Mesh *	lg_obj2vbo (const char *mesh_name, FILE *stream, zboolean invert_z, zboolean normalize_xyz, zboolean horiz_center, zboolean vert_center, zboolean vert_bottom)
int	lg_mtl_parser (const char *mtl_file, LG_Material *mat[])
int	lg_vertex_cmp (Vertex_uv_n *v1, Vertex_uv_n *v2, zboolean tex_coords, zboolean normals)
void	lg_vbo_and_ibo_info (Vertex_uv_n *vbo_data, uint32_t *ibo_data, uint32_t vbo_size, uint32_t ibo_size, lg_vertex_type vertex_type, int n_lines_max)
void	lg_vb_info (Vertex *vb_data, uint32_t vb_size, int n_lines_max, const char *line_start, zboolean is_triangle_mesh)
void	lg_vb_rgba_info (Vertex_rgba *vb_data, uint32_t vb_size, int n_lines_max, const char *line_start, zboolean is_triangle_mesh)
zboolean	lg_objparser_check_consistency ()

Detailed Description

=== The Wawefront OBJ file parser ===

Function Documentation

lg_obj2vbo()

LG_Mesh* lg_obj2vbo	(	const char *	mesh_name,
		FILE *	stream,
		zboolean	invert_z,
		zboolean	normalize_xyz,
		zboolean	horiz_center,
		zboolean	vert_center,
		zboolean	vert_bottom
	)

Parse a readable stream (an opened OBJ file) and create the mesh VBO and IBO

Will create a Vertex_uv_n VBO (see lg_vertex.h)

We use the basename of the OBJ file only to set mesh->name but it's not used anywhere else, as the file is already opened (saying that to avoid any possible confusion)

Parameters

mesh_name	OBJ file name - only BASENAME is used
stream	An open stream of the OBJ file
invert_z	Invert z spatial coord (left_handed vs right_handed coords sys) - STILL EXPERIMENTAL
normalize_xyz	Normalize spatial coords
horiz_center	Center mesh horizontally
vert_center	Center mesh vertically, if vert_bottom is not set
vert_bottom	Set mesh origin vertically at bottom, override vert_center

Returns

The new mesh

lg_mtl_parser()

int lg_mtl_parser	(	const char *	mtl_file,
		LG_Material *	mat[]
	)

Parse a MTL file

Get materials names and associated textures

Don't set indice (it's done later)

Parameters

mtl_file	MTL file name
tex	Address of an array of N_MAX_MAT_PER_OBJ pointers to LG_Material structs

Returns

Num of texture materials found if OK, -1 on error

lg_vertex_cmp()

int lg_vertex_cmp	(	Vertex_uv_n *	v1,
		Vertex_uv_n *	v2,
		zboolean	tex_coords,
		zboolean	normals
	)

Compare two vertices

FIXME: should use adaptative epsilon or another better way of comparison.

Parameters

v1	Addr of first Vertex_uv_n
v2	Addr of second Vertex_uv_n
tex_coords	Also compare texture coords
normals	Also compare normals

Returns

0 if vertices are equal, -1 otherwise

lg_vbo_and_ibo_info()

void lg_vbo_and_ibo_info	(	Vertex_uv_n *	vbo_data,
		uint32_t *	ibo_data,
		uint32_t	vbo_size,
		uint32_t	ibo_size,
		lg_vertex_type	vertex_type,
		int	n_lines_max
	)

Print out nicely VBO and IBO (arrays of Vertex_uv_n and uint32_t)

vertex_type is one of lg_vertex_type: WITH_COORDS_ONLY, WITH_TEXCOORDS, WITH_NORMALS, WITH_TEXCOORDS_AND_NORMALS

Parameters

vbo_data	Pointer to (Vertex_uv_n) VBO with interleaved vertex data - sizeof(Vertex_uv_n) = 24
ibo_data	Pointer to (uint32_t) IBO, indices start at 0, sizeof(uint32_t) = 4
vbo_size	VBO size (uint32_t)
ibo_size	IBO size uint32_t
vertex_type	A lg_vertex_type, see above
n_lines_max	Print out up to n_lines_max lines

lg_vb_info()

void lg_vb_info	(	Vertex *	vb_data,
		uint32_t	vb_size,
		int	n_lines_max,
		const char *	line_start,
		zboolean	is_triangle_mesh
	)

Print out nicely a Vertex (ie spatial coords only) buffer info

v[1/2/3] applies only for triangle meshes

Parameters

vb_data	Pointer to a Vertex buffer
vb_size	Buffer size (uint32_t)
n_lines_max	Print out up to n_lines_max lines
line_start	String starting each line
is_triangle_mesh

lg_vb_rgba_info()

void lg_vb_rgba_info	(	Vertex_rgba *	vb_data,
		uint32_t	vb_size,
		int	n_lines_max,
		const char *	line_start,
		zboolean	is_triangle_mesh
	)

Print out nicely a Vertex_rgba (ie spatial coords + RGBA color) buffer info, actually spatial coords info ONLY

v[1/2/3] applies only for triangle meshes

Parameters

vb_data	Pointer to a Vertex_rgba buffer
vb_size	Buffer size (uint32_t)
n_lines_max	Print out up to n_lines_max lines
line_start	String starting each line
is_triangle_mesh

lg_objparser_check_consistency()

zboolean lg_objparser_check_consistency

(

)

Only for init-time checking

Returns

LG_OK if OK, LG_ERROR on error