lg_mesh.c File Reference

Functions
LG_Mesh *	lg_mesh_load (LG_Path path, LG_LoadMesh_Flags flags)
LG_Mesh *	lg_mesh_new_from_obj (LG_Path path, zboolean invert_z, zboolean normalize_xyz, zboolean horiz_center, zboolean vert_center, zboolean vert_bottom)
LG_Mesh *	lg_mesh_new_from_fbx (LG_Path path, zboolean invert_z, zboolean normalize_xyz, zboolean horiz_center, zboolean vert_center, zboolean vert_bottom)
void	lg_mesh_free (LG_Mesh *mesh)
void	lg_mesh_free_v2 (LG_Mesh **mesh)
int	lg_bmesh_save_to_file (LG_Path path, LG_Mesh *mesh)
LG_Mesh *	lg_bmesh_load_from_file (LG_Path path)
int	lg_mesh_reload_mats (LG_Mesh *mesh)
void	lg_serialize_LG_Material_64_to_32 (Serializable_LG_Material *s_mat, LG_Material *mat)
void	lg_unserialize_LG_Material_32_to_64 (LG_Material *mat, Serializable_LG_Material *s_mat)
void	lg_serialize_LG_Mesh_64_to_32 (Serializable_LG_Mesh *s_mesh, LG_Mesh *mesh)
void	lg_unserialize_LG_Mesh_32_to_64 (LG_Mesh *mesh, Serializable_LG_Mesh *s_mesh)
LG_LoadMesh_Flags	lg_loadmesh_flags (zboolean save_as_bmesh_linux, zboolean invert_z, zboolean normalize_xyz, zboolean horiz_center, zboolean vert_center, zboolean vert_bottom)
void	lg_mesh_override_bounding_cuboid_color (LG_Mesh *mesh, LG_Color_u color)
void	lg_mesh_info (LG_Mesh *mesh, int show_first_n)
char *	lg_mesh_info_to_string (LG_Mesh *mesh, int show_first_n)
char *	lg_replace_file_extension (const char *path, const char *new_ext)

Detailed Description

This module deals with meshes, ie data that will feed VBOs and IBOs for fast and efficient drawing.

You can only use this func to load meshes:

LG_Mesh *lg_mesh_load(path, flags)

and you can only use this func when done with a mesh:

void lg_mesh_free(LG_Mesh *)

and just ignore the details.

(Use everything here only if you know what you're doing).

NEW CONVENTIONS FOR PATHS / FILE NAMES AS FUNC ARGS:

- full_path      -> Absolute path, include file name (default for paths)
- relative_path  -> Relative path, include file name = sub_dir1/sub_dir2/---/file_name
- file_name      -> Basename only, always with extension

In funcs names:

- bla_bla()
  vs
- bla_bla_relpath()

This module deals with meshes, ie data that will feed VBOs and IBOs for fast and efficient drawing.

You can/should only use this func to load meshes, if they're all in an <assets_dir> folder, defined by the macro ASSETS_DIR

// The <assets_dir> structure:
//
//      <assets_dir>
//       /        \
//   <images>   <meshes>
//      |        /    \
// <textures> <bmesh> <obj>
 
#define ASSETS_DIR <assets_dir>
 
LG_Mesh *lg_mesh_load(const char *full_path, LG_LoadMesh_Flags flags)
 
// LG_Mesh struct is defined in lg_mesh.h
 
// full_path = full path of mesh file, with extension OBJ or FBX or BMESH
 
// Mesh loading flags
typedef struct {
   zboolean        save_to_assets;         // Save to assets as BMESH, otherwise to cache - on Android, should always be set to FALSE as you can't write to assets
   zboolean        invert_z;               // Invert z spatial coord - should be set to TRUE if mesh uses RH coords sys, FALSE if mesh uses LH coords sys
   zboolean        normalize_xyz;
   zboolean        horiz_center;
   zboolean        vert_center;            // Center mesh vertically, if vert_bottom is not set
   zboolean        vert_bottom;            // Set mesh origin vertically at bottom, override vert_center
} LG_LoadMesh_Flags;

and you can/should only use this func when done with a mesh:

void lg_mesh_free(LG_Mesh *)

and just ignore the details.

(Use everything here only if you know what you're doing).

NEW CONVENTIONS FOR PATHS / FILE NAMES AS FUNC ARGS:

- full_path      -> Absolute path, include file name (default for paths)
- relative_path  -> Relative path, include file name = sub_dir1/sub_dir2/---/file_name
- file_name      -> Basename only, always with extension

In funcs names:

- bla_bla()
  vs
- bla_bla_relpath()

Function Documentation

lg_mesh_load()

LG_Mesh * lg_mesh_load	(	LG_Path	path,
		LG_LoadMesh_Flags	flags
	)

Load OBJ or FBX or BMESH mesh file

If all your meshes (OBJ, FBX, BMESH) are in the ASSETS dir, then this is the entry point for loading them and the only func you need to call

Valid extensions are OBJ, FBX, and BMESH

// The ASSETS dir structure:
//
//      <assets_dir>
//       /        \
//   <images>   <meshes>
//      |        /    \
// <textures> <bmesh> <obj>
 
// Mesh loading flags
typedef struct {
   zboolean        save_as_bmesh_linux;    // If OBJ or FBX loaded from assets, save as a BMESH asset, only on Linux
   zboolean        invert_z;               // Invert z spatial coord - should be set to TRUE if mesh uses RH coords sys, FALSE if mesh uses LH coords sys
   zboolean        normalize_xyz;
   zboolean        horiz_center;
   zboolean        vert_center;            // Center mesh vertically, if vert_bottom is not set
   zboolean        vert_bottom;            // Set mesh origin vertically at bottom, override vert_center
} LG_LoadMesh_Flags;

Usage examples:

LG_LoadMesh_Flags flags = lg_loadmesh_flags(FALSE, FALSE, NORMALIZE_XYZ, HORIZ_CENTER, VERT_CENTER, FALSE);
 
LG_Mesh *mesh1 = lg_mesh_load(lg_path('meshes/obj/file1.obj', IN_ASSETS), flags);
 
LG_Mesh *mesh2 = lg_mesh_load(lg_path('meshes/bmesh/file2.bmesh', IN_ASSETS), flags);

On Linux, if OBJ or FBX file was successfully loaded from assets and flags.save_as_bmesh_linux is set to TRUE, it will be saved as a BMESH asset

BMESH is LibGame binary format for meshes - optimized, faster to load, not requiring parsing

WARNING: FBX support is not complete yet

Parameters

path	LG_Path of mesh file, with extension OBJ or FBX or BMESH
flags	Apply to OBJ/FBX meshes loading: save_as_bmesh_linux, invert_z, normalize_xyz, horiz_center, vert_center, vert_bottom

Returns

Pointer to LG_Mesh if OK, NULL on error

lg_mesh_new_from_obj()

LG_Mesh * lg_mesh_new_from_obj	(	LG_Path	path,
		zboolean	invert_z,
		zboolean	normalize_xyz,
		zboolean	horiz_center,
		zboolean	vert_center,
		zboolean	vert_bottom
	)

Create mesh from OBJ file.

Read data from WAVEFRONT OBJ files: vertex/index values for v (coords), vt (texture coords), vn (normals), f (triangular faces), mtllib, usemtl (materials/textures stuff), plus newmtl, and map_K* (in MTL files).

Other data is ignored so far.

=== WARNING: MESHES MUST BE PURE-TRIANGULAR ===

Will create a Vertex_uv_n VBO (see lg_vertex.h).

NO-OP on Android as BMESH files should be used instead

Using MeshLab filters:
   remeshing, simplification and reconstruction
           turn into a pure-triangle mesh
Also:
   normals, curvatures and orientation
           transform: translate, center, set origin
                   -> center on layer bbox
   normals, curvatures and orientation
           transform: scale, normalize
                   -> scale to unit bbox

Parameters

path	LG_PATH to OBJ file (with extension OBJ)
invert_z	Invert z spatial coord - should be set to TRUE if mesh uses RH coords sys, FALSE if mesh uses LH coords sys
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

A new LG_Mesh instance if OK, NULL on error

lg_mesh_new_from_fbx()

LG_Mesh * lg_mesh_new_from_fbx	(	LG_Path	path,
		zboolean	invert_z,
		zboolean	normalize_xyz,
		zboolean	horiz_center,
		zboolean	vert_center,
		zboolean	vert_bottom
	)

Create mesh from FBX file.

Parameters

path	LG_PATH to FBX file (with extension FBX)
invert_z	Invert z spatial coord - should be set to TRUE if mesh uses RH coords sys, FALSE if mesh uses LH coords sys
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

A new LG_Mesh instance if OK, NULL on error

lg_mesh_free()

void lg_mesh_free

(

LG_Mesh *

mesh

)

Free mesh.

Parameters

mesh	Pointer to mesh

lg_mesh_free_v2()

void lg_mesh_free_v2

(

LG_Mesh **

mesh

)

NEW - needs extensive testing

Free mesh v2.

Take pointer to pointer to mesh arg, so that it can be nullified afterwards.

Parameters

mesh	Pointer to pointer to mesh

lg_bmesh_save_to_file()

int lg_bmesh_save_to_file	(	LG_Path	path,
		LG_Mesh *	mesh
	)

Save mesh in BINARY MESH (.bmesh) format. Don't add suffix BINARY_MESH_EXT, as it's done automagically.

BINARY MESH (.bmesh) file format
================================
- Header = Serializable_LG_Mesh
           -> header_size = lg_align_up_to_next_4_bytes_boundary((void *)sizeof(Serializable_LG_Mesh))
- VBO data block - aligned to 4 bytes boundaries
   -> starting at header_size
- IBO data block - aligned to 4 bytes boundaries
   -> starting at header_size + lg_align_up_to_next_4_bytes_boundary((void *)(uint64_t)mesh->vbo_size)

Parameters

path	LG_Path to BMESH file
mesh	Pointer to a LG_Mesh

Returns

LG_OK if OK, error code otherwise

lg_bmesh_load_from_file()

LG_Mesh * lg_bmesh_load_from_file

(

LG_Path

path

)

Load mesh from BINARY MESH (.bmesh) file. Don't add suffix BINARY_MESH_EXT, as it's done automagically.

BINARY MESH (.bmesh) file format
================================
- Header = Serializable_LG_Mesh
           -> header_size = lg_align_up_to_next_4_bytes_boundary((void *)sizeof(Serializable_LG_Mesh))
- VBO data block - aligned to 4 bytes boundaries
   -> starting at header_size
- IBO data block - aligned to 4 bytes boundaries
   -> starting at header_size + lg_align_up_to_next_4_bytes_boundary((void *)(uint64_t)mesh->vbo_size)

Parameters

path	LG_Path to BMESH file
mesh	Pointer to an array of pointers to LG_Mesh

Returns

LG_OK if OK, error code otherwise

lg_mesh_reload_mats()

int lg_mesh_reload_mats

(

LG_Mesh *

mesh

)

Reload materials textures correctly, when mesh is not loaded from OBJ file.

Parameters

mesh	Pointer to a LG_Mesh

Returns

LG_OK if OK, error code otherwise

lg_serialize_LG_Material_64_to_32()

void lg_serialize_LG_Material_64_to_32	(	Serializable_LG_Material *	s_mat,
		LG_Material *	mat
	)

Serialize a LG_Material instance

Parameters

s_mat	Pointer to a Serializable_LG_Material
mat	Pointer to a Serializable_LG_Material

lg_unserialize_LG_Material_32_to_64()

void lg_unserialize_LG_Material_32_to_64	(	LG_Material *	mat,
		Serializable_LG_Material *	s_mat
	)

Unserialize a LG_Material instance

Parameters

mat	Pointer to a Serializable_LG_Material
s_mat	Pointer to a Serializable_LG_Material

lg_serialize_LG_Mesh_64_to_32()

void lg_serialize_LG_Mesh_64_to_32	(	Serializable_LG_Mesh *	s_mesh,
		LG_Mesh *	mesh
	)

Serialize a LG_Mesh instance

Parameters

s_mesh	Pointer to a Serializable_LG_Mesh
mesh	Pointer to a LG_Mesh

lg_unserialize_LG_Mesh_32_to_64()

void lg_unserialize_LG_Mesh_32_to_64	(	LG_Mesh *	mesh,
		Serializable_LG_Mesh *	s_mesh
	)

Unserialize a LG_Mesh instance

Parameters

mesh	Pointer to a LG_Mesh
s_mesh	Pointer to a Serializable_LG_Mesh

lg_loadmesh_flags()

LG_LoadMesh_Flags lg_loadmesh_flags	(	zboolean	save_as_bmesh_linux,
		zboolean	invert_z,
		zboolean	normalize_xyz,
		zboolean	horiz_center,
		zboolean	vert_center,
		zboolean	vert_bottom
	)

Mesh loading flags.

See lg_mesh_load().

You can use these helper, which are all set to TRUE:

• SAVE_AS_BMESH_LINUX
• INVERT_Z
• NORMALIZE_XYZ
• VERT_CENTER
• VERT_BOTTOM

Parameters

save_as_bmesh_linux	If OBJ or FBX loaded from assets, save as a BMESH asset, only on Linux
invert_z	Invert z spatial coord - should be set to TRUE if mesh uses RH coords sys, FALSE if mesh uses LH coords sys
normalize_xyz
horiz_center
vert_center	Center mesh vertically, if vert_bottom is not set
vert_bottom	Set mesh origin vertically at bottom, override vert_center

Returns

A LG_LoadMesh_Flags

lg_mesh_override_bounding_cuboid_color()

void lg_mesh_override_bounding_cuboid_color	(	LG_Mesh *	mesh,
		LG_Color_u	color
	)

Override color of mesh bounding cuboid AND bounding cuboid VB

Why is this needed ? bc color is set at mesh creation time

mesh->b_cuboid = LG_Cuboid // Bounding cuboid mesh->Lines3D_VB = b_cuboid_l3d_vb // Lines3D_VB from bounding cuboid

Parameters

mesh	Pointer to a LG_Mesh
color	Color as a LG_Color_u

lg_mesh_info()

void lg_mesh_info	(	LG_Mesh *	mesh,
		int	show_first_n
	)

Print out LG_Mesh info.

Parameters

mesh	Pointer to a LG_Mesh
show_first_n	Show first n elements of: mesh->i_mat_in_vbo[N_NEWMTL_USEMTL_TAGS_MAX] mesh->i_mat_in_lib[N_NEWMTL_USEMTL_TAGS_MAX]

lg_mesh_info_to_string()

char * lg_mesh_info_to_string	(	LG_Mesh *	mesh,
		int	show_first_n
	)

Get LG_Mesh info as a string

NOTE: mesh->b_cuboid is not output (so far)

Parameters

mesh	Pointer to a LG_Mesh
show_first_n	Show first n elements of: mesh->i_mat_in_vbo[N_NEWMTL_USEMTL_TAGS_MAX] mesh->i_mat_in_lib[N_NEWMTL_USEMTL_TAGS_MAX]

Returns

LG_Mesh info as a string - must be freed when done, or NULL on error

lg_replace_file_extension()

char * lg_replace_file_extension	(	const char *	path,
		const char *	new_ext
	)

Replace file extension with another extension, ie 'bla_bla/hello.old_ext' -> 'bla_bla/hello.new_ext'

Extension must not include leading dot

Remove trailing dot if new_ext is empty string

Returned new path must be freed after use (dynamically allocated)

lg_replace_file_extension('hello.vbo', 'blob') = 'hello.blob'
lg_replace_file_extension('bla_bla_1/bla_bla_2.vbo', 'blob') = 'bla_bla_1/bla_bla_2.blob'
lg_replace_file_extension('bla_bla_1/bla_bla_2.v', 'z') = 'bla_bla_1/bla_bla_2.z'
lg_replace_file_extension('hello1.hello2.vbo', 'blob') = 'hello1.hello2.blob'
lg_replace_file_extension('v.1', '2') = 'v.2'
lg_replace_file_extension('v1', '2') = 'v1.2'
lg_replace_file_extension('bla_bla_1/bla_bla_1', '2') = 'bla_bla_1/bla_bla_1.2'
lg_replace_file_extension('.1', '2') = '.2'
lg_replace_file_extension('vbo.1', '') = 'vbo'
lg_replace_file_extension('v.1', '') = 'v'
lg_replace_file_extension('1.', '2') = '1.2'
lg_replace_file_extension('1.', '') = '1'

Parameters

path
new_ext

Returns

New path with swapped extension if OK, NULL on error