lg_obj_parser.c File Reference

Functions
LG_Mesh *	lg_obj2vbo (LG_Path obj_path, FILE *stream, zboolean invert_z, zboolean normalize_xyz, zboolean horiz_center, zboolean vert_center, zboolean vert_bottom)
int	lg_mtl_parser (const char *mtl_filename, LG_Path obj_path, LG_Material *mat[])
int	lg_vertex_cmp (Vertex_uv_n *v1, Vertex_uv_n *v2, zboolean tex_coords, zboolean normals)
zboolean	lg_objparser_check_consistency ()

Detailed Description

=== The Wawefront OBJ file parser ===

Function Documentation

lg_obj2vbo()

LG_Mesh * lg_obj2vbo	(	LG_Path	obj_path,
		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 obj_path (user-provided LG_Path to the OBJ file) to set mesh->path and locate MTL file and textures

The MTL file is expected to be in the same dir as the OBJ file

Doesn't close the stream, you'll have to do it yourself after the func returns

Parameters

obj_path	User-provided LG_Path to the OBJ file
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 or NULL on error

lg_mtl_parser()

int lg_mtl_parser	(	const char *	mtl_filename,
		LG_Path	obj_path,
		LG_Material *	mat[]
	)

Parse a MTL file

Get (materials) names and associated textures referenced by 'map_K' tags

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

Parameters

mtl_filename	'mtllib' tag value in OBJ file, ie name of MTL files - expected to be in the same dir as the OBJ file
obj_path	LG_Path to OBJ file
mat	Pointer to an array of N_NEWMTL_USEMTL_TAGS_MAX pointers to LG_Material structs

Returns

Num of texture references ('map_K') 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	Pointer to first Vertex_uv_n
v2	Pointer to second Vertex_uv_n
tex_coords	Also compare texture coords
normals	Also compare normals

Returns

0 if vertices are equal, -1 otherwise

lg_objparser_check_consistency()

zboolean lg_objparser_check_consistency

(

)

Only for init-time checking

Returns

LG_OK if OK, LG_ERROR on error