lg_scene.c File Reference

Functions
LG_Scene	lg_scene_new (int id, LG_Camera *cam1, LG_Light light1, Rec2Df landscape_rec, uint16_t grid_width)
void	lg_scene_free (LG_Scene *scene)
LG_SceneNode *	lg_scenenode_new_and_set (int id, LG_SceneNode *parent, const char *mesh_file, LG_LoadMesh_Flags flags, vec3_t transl, LG_Quat orientation, vec3_t scaling)
LG_SceneNode *	lg_mesh_NTOS_array_to_scenenodes (LG_SceneNode *node, LG_LoadMesh_Flags flags, LG_Mesh_NTOS *mesh_ntos, int n_mesh_ntos)
mat4_t	lg_get_TRS_matrix_from_TOS_v (vec3_t transl, LG_EulerAng orientation, vec3_t scaling, const char *rot_order)
zboolean	lg_set_TRS_matrix_from_mesh_NTOS (mat4_t *m_TRS, LG_Mesh_NTOS *tos)
void	lg_mesh_NTOS_array_info (LG_Mesh_NTOS *mesh_ntos, int n_mesh_ntos)
LG_SceneDZ	lg_scenedz_load_from_assets (const char *path)
LG_SceneDZ	lg_scenedz_load_from_file (const char *path)
zboolean	lg_scenedz_save_to_file (LG_SceneDZ *scenedz, const char *path)
zboolean	lg_create_wr_scenes_dir ()
void	lg_scene_set_from_scenedz (LG_Scene *scene, LG_SceneDZ *scenedz)
void	lg_scenedz_set_from_scene (LG_SceneDZ *scenedz, LG_Scene *scene)
LG_SceneNode *	lg_generate_scenenodes_from_scenedz (LG_SceneDZ *sdz, LG_LoadMesh_Flags flags)

Detailed Description

 === Higher level scene/frame stuff ===

 The starting point for scenes

Function Documentation

lg_scene_new()

LG_Scene lg_scene_new	(	int	id,
		LG_Camera *	cam1,
		LG_Light	light1,
		Rec2Df	landscape_rec,
		uint16_t	grid_width
	)

Create and init a new scene

Can not contain more than MESH_NTOS_MAX_NUM mesh references

LG_Mesh_NTOS, LG_Scene, and LG_SceneDZ are defined in lg_scene_graph.h

// NTOS stands for Name and TOS (Transl/Orientation/Scaling)
// Use float for LG_EulerAng
 
typedef union {
   struct {
           // Name
           char    name[LG_MESH_NAME_MAX_LEN + 1]; // OBJ/FBX basename
           // Transl.
           float   x_t;
           float   y_t;
           float   z_t;
           // Orientation as LG_EulerAng
           float   x_o;
           float   y_o;
           float   z_o;
           // Scaling
           float   x_s;
           float   y_s;
           float   z_s;
           // Rot. order
           char    rot_order[4];
   };
   struct {
           char    name2[LG_MESH_NAME_MAX_LEN + 1];
           float   v[9];
           char    rot_order2[4];
   };
} LG_Mesh_NTOS;
 
typedef struct {
   int                 id;        // Set to -1 on error
   LG_Camera           *cam1;
   LG_Light            light1;
   Rec2Df              landscape_rec;
   LG_SceneNode        *root;
   LG_SceneNode        *grid;
   LG_SceneNode        *xyz_arrows;
   LG_Mesh_NTOS        meshes_ntos[MESH_NTOS_MAX_NUM];
   int                 n_mesh_ntos;
} LG_Scene;
 
// Serialized LG_Scene data - not everything
// DZ stands for Data serialiZation (huh ?)
typedef struct {
   LG_Camera           cam;
   Rec2Df              landscape_rec;
   LG_Mesh_NTOS        meshes_ntos[MESH_NTOS_MAX_NUM];
   int                 n_mesh_ntos;
} LG_SceneDZ;

Generated nodes:

• root -> parent of grid and xyz_arrows, id = 0, type = ROOT
• grid -> with an initialized Lines3D_VB horizontal grid, id = 1, type = GRID
• xyz_arrows -> with an initialized Lines3D_VB xyz_arrows, id = 2, type = LINES3D

Parameters

id	Scene's id, set to -1 on error
cam1	A pointer to a LG_Camera
light1	A LG_Light
landscape_rec	A Rec2Df, should be centered
grid_width	Grid width, ie number of units along one row or one column, should be even - if odd, we substract one

Returns

An initialized LG_Scene if OK, id set to -1 on error

lg_scene_free()

void lg_scene_free

(

LG_Scene *

scene

)

Free scene root, grid, and xyz_arrows nodes

Parameters

scene

A LG_Scene

lg_scenenode_new_and_set()

LG_SceneNode* lg_scenenode_new_and_set	(	int	id,
		LG_SceneNode *	parent,
		const char *	mesh_file,
		LG_LoadMesh_Flags	flags,
		vec3_t	transl,
		LG_Quat	orientation,
		vec3_t	scaling
	)

Helper func to create and set a new LG_SceneNode instance

Create node, add node to scene graph, load node's mesh, and set node's local matrix

Helper macros for less confusion:

#define transl_v3(x, y, z)     vec3(x, y, z)
#define scaling_v3(x, y, z)    vec3(x, y, z)

Mesh must be freed when done with the scene

Parameters

id	Node's id
parent	A pointer to a scene graph node
mesh_file	Relative path to mesh file to load, inside the mesh folder
flags	Apply to mesh: force_reload, invert_z, normalize_xyz, horiz_center, vert_center, vert_bottom
transl	Translation/position vec3
orientation	Orientation quat
scaling	Scaling vec3

Returns

A pointer to a LG_SceneNode if OK, NULL on error - must be freed afterwards

lg_mesh_NTOS_array_to_scenenodes()

LG_SceneNode* lg_mesh_NTOS_array_to_scenenodes	(	LG_SceneNode *	node,
		LG_LoadMesh_Flags	flags,
		LG_Mesh_NTOS *	mesh_ntos,
		int	n_mesh_ntos
	)

Get an array of LG_Mesh_NTOS and create and set scenenodes

NTOS stands for Name and TOS (Transl/Orientation/Scaling)

Generated scenenodes id start at MNTOS_ARRAY_INDEX_TO_SCENENODE_ID

Example code #1:

LG_LoadMesh_Flags flags1 = lg_loadmesh_flags(FALSE, FALSE, NORMALIZE_XYZ, HORIZ_CENTER, FALSE, VERT_BOTTOM);
 
LG_Mesh_NTOS mesh_ntos[] = {
        {{"obj/shark1.obj",       0, 40, 0,       0, 0, 0,    25, 25, 25   ROT_ORDER}},
        {{"obj/pikachu2.obj",     -50, 0, 50,     0, 0, 0,    25, 25, 25   ROT_ORDER}},
        {{"obj/tree2.obj",        50, 0, 50,      0, 0, 0,    25, 25, 25   ROT_ORDER}},
        {{"obj/windmill1.obj",    -50, 0, -50,    0, 0, 0,    25, 25, 25   ROT_ORDER}},
        {{"obj/cube3.obj",        50, 0, -50,     0, 0, 0,    12, 12, 12   ROT_ORDER}}};
 
int n_mesh_ntos =  (int)(sizeof(mesh_ntos) / sizeof(LG_Mesh_NTOS));
 
// Generate nodes from a LG_Mesh_NTOS array
LG_SceneNode *first_obj_node = lg_mesh_NTOS_array_to_scenenodes(first_obj_node, flags1, (LG_Mesh_NTOS *)mesh_ntos, n_mesh_ntos);

Example code #2:

LG_Scene scene = lg_scene_new(...);
LG_SceneDZ sdz = lg_scenedz_load_from_file(lg_app_wr_file("scenes/hello_1.scene"));
lg_scene_set_from_scenedz(&scene, &sdz);
 
// Generate nodes from a LG_Mesh_NTOS array
LG_SceneNode *first_obj_node = lg_mesh_NTOS_array_to_scenenodes(first_obj_node, flags1, (LG_Mesh_NTOS *)scene.meshes_ntos, scene.n_mesh_ntos);
 
lg_scenedz_set_from_scene(&sdz, &lev->scene);
lg_scenedz_save_to_file(&sdz, lg_app_wr_file("scenes/hello_2.scene"));

Parameters

node	A scene node
flags	Flags for mesh loading
mesh_ntos	An array of LG_Mesh_NTOS
n_mesh_ntos	Num of LG_Mesh_NTOS in the array

Returns

The same scene node

lg_get_TRS_matrix_from_TOS_v()

mat4_t lg_get_TRS_matrix_from_TOS_v	(	vec3_t	transl,
		LG_EulerAng	orientation,
		vec3_t	scaling,
		const char *	rot_order
	)

Create a TRS matrix (Transl/Rotation/Scaling) from TOS values (Transl/Orientation/Scaling)

Parameters

transl	Translation vector
orientation	Orientation LG_EulerAng
scaling	Scaling vector

lg_set_TRS_matrix_from_mesh_NTOS()

zboolean lg_set_TRS_matrix_from_mesh_NTOS	(	mat4_t *	m_TRS,
		LG_Mesh_NTOS *	tos
	)

Set an existing TRS matrix (Transl/Rotation/Scaling) from a LG_Mesh_NTOS

Parameters

m_TRS	Pointer to a mat4_t
tos	Pointer to a LG_Mesh_NTOS
scaling	Scaling vector

lg_mesh_NTOS_array_info()

void lg_mesh_NTOS_array_info	(	LG_Mesh_NTOS *	mesh_ntos,
		int	n_mesh_ntos
	)

Print out LG_Mesh_NTOS[] info

Parameters

mesh_ntos	An array of LG_Mesh_NTOS
n_mesh_ntos	Num of LG_Mesh_NTOS in the array

lg_scenedz_load_from_assets()

LG_SceneDZ lg_scenedz_load_from_assets

(

const char *

path

)

Load a LG_Scene from a file in the ASSETS/SCENES_DIR folder

Parameters

path	Relative path to scene file, inside env->assets_dir/scenes

Returns

A new LG_Scene, id set to -1 on error

lg_scenedz_load_from_file()

LG_SceneDZ lg_scenedz_load_from_file

(

const char *

path

)

Load a LG_SceneDZ from a file in the APP WRITABLE folder

Parameters

path	Path to scene file, inside env->app_wr_dir

Returns

A new LG_SceneDZ, n_mesh_ntos set to -1 on error

lg_scenedz_save_to_file()

zboolean lg_scenedz_save_to_file	(	LG_SceneDZ *	scenedz,
		const char *	path
	)

Save a LG_SceneDZ to a file in the APP WRITABLE folder

Parameters

scene	Pointer a to LG_SceneDZ
path	Path to scene file, inside env->app_wr_dir

Returns

TRUE if OK, FALSE on error

lg_create_wr_scenes_dir()

zboolean lg_create_wr_scenes_dir

(

)

Create the scene folder (SCENES_DIR) in the APP WRITABLE folder

Returns

TRUE if OK, FALSE on error

lg_scene_set_from_scenedz()

void lg_scene_set_from_scenedz	(	LG_Scene *	scene,
		LG_SceneDZ *	scenedz
	)

Set LG_Scene data from LG_SceneDZ data

-> cam, landscape_rec, meshes_ntos[MESH_NTOS_MAX_NUM], and n_mesh_ntos

Parameters

scene	Pointer to a LG_Scene
scenedz	Pointer to a LG_SceneDZ

lg_scenedz_set_from_scene()

void lg_scenedz_set_from_scene	(	LG_SceneDZ *	scenedz,
		LG_Scene *	scene
	)

Set LG_SceneDZ data from LG_Scene data

-> cam, landscape_rec, meshes_ntos[MESH_NTOS_MAX_NUM], and n_mesh_ntos

Parameters

scenedz	Pointer to a LG_SceneDZ
scene	Pointer to a LG_Scene

lg_generate_scenenodes_from_scenedz()

LG_SceneNode* lg_generate_scenenodes_from_scenedz	(	LG_SceneDZ *	sdz,
		LG_LoadMesh_Flags	flags
	)

Helper func to generate scene nodes (LG_SceneNode *) from a LG_SceneDZ and mesh files

You can then add this node to your scene root node

Top node:

• node.id = 3
• node->name = "first_obj_node"
• node->type = FIRST_OBJ

Parameters

sdz	Pointer to a LG_SceneDZ
flags	Mesh loading flags

Returns

Pointer to a new scene node