math.h

一个用于智能手机的多媒体库适合S60 WinCE的跨平台开发库

void gf_rect_from_bbox(GF_Rect *rc, GF_BBox *box);
/*!\brief bounding box expansion
 *
 *Checks if a point is inside a bounding box and updates the bounding box to include it if not the case
 *\param box the bounding box object
 *\param pt the 3D point to check
*/
void gf_bbox_grow_point(GF_BBox *box, GF_Vec pt);
/*!performs the union of two bounding boxes*/
void gf_bbox_union(GF_BBox *b1, GF_BBox *b2);
/*!checks if two bounding boxes are equal or not*/
Bool gf_bbox_equal(GF_BBox *b1, GF_BBox *b2);
/*!checks if a point is inside a bounding box or not*/
Bool gf_bbox_point_inside(GF_BBox *box, GF_Vec *p);
/*!\brief get box vertices
 *
 *Returns the 8 bounding box vertices given the minimum and maximum edge. Vertices are ordered to respect 
 "p-vertex indexes", (vertex from a box closest to plane) and so that n-vertex (vertex from a box farthest from plane) 
 is 7-p_vx_idx
 *\param bmin minimum edge of the box
 *\param bmax maximum edge of the box
 *\param vecs list of 8 3D points used to store the vertices.
*/
void gf_bbox_get_vertices(GF_Vec bmin, GF_Vec bmax, GF_Vec *vecs);


/*!\brief matrix initialization
 *\hideinitializer
 *
 *Inits the matrix to the identity matrix
*/
#define gf_mx_init(_obj) { memset((_obj).m, 0, sizeof(Fixed)*16); (_obj).m[0] = (_obj).m[5] = (_obj).m[10] = (_obj).m[15] = FIX_ONE; }
/*!\brief matrix copy
 *\hideinitializer
 *
 *Copies the matrix _from to the matrix _obj
*/
#define gf_mx_copy(_obj, from) memcpy(&(_obj), &(from), sizeof(GF_Matrix));
/*!\brief matrix constructor from 2D
 *
 *Initializes a 3D matrix from a 2D matrix.\note all z-related coefficients will be set to default.
*/
void gf_mx_from_mx2d(GF_Matrix *mx, GF_Matrix2D *mat2D);
/*!\brief matrix identity testing
 *
 *Tests if two matrices are equal or not.
 \return 1 if matrices are same, 0 otherwise
*/
Bool gf_mx_equal(GF_Matrix *mx1, GF_Matrix *mx2);
/*!\brief matrix translation
 *
 *Translates a matrix 
 *\param mx the matrix being transformed. Once the function is called, contains the result matrix
 *\param tx horizontal translation
 *\param ty vertical translation
 *\param tz depth translation
*/
void gf_mx_add_translation(GF_Matrix *mx, Fixed tx, Fixed ty, Fixed tz);
/*!\brief matrix scaling
 *
 *Scales a matrix 
 *\param mx the matrix being transformed. Once the function is called, contains the result matrix
 *\param sx horizontal translation scaling
 *\param sy vertical translation scaling
 *\param sz depth translation scaling
*/
void gf_mx_add_scale(GF_Matrix *mx, Fixed sx, Fixed sy, Fixed sz);
/*!\brief matrix rotating
 *
 *Rotates a matrix 
 *\param mx the matrix being transformed. Once the function is called, contains the result matrix
 *\param angle rotation angle in radians
 *\param x horizontal coordinate of rotation axis
 *\param y vertical coordinate of rotation axis
 *\param z depth coordinate of rotation axis
*/
void gf_mx_add_rotation(GF_Matrix *mx, Fixed angle, Fixed x, Fixed y, Fixed z);
/*!\brief matrices multiplication 
 *
 *Multiplies a matrix with another one mx = mx*mul
 *\param mx the matrix being transformed. Once the function is called, contains the result matrix
 *\param mul the matrix to add
*/
void gf_mx_add_matrix(GF_Matrix *mx, GF_Matrix *mul);
/*!\brief affine matrix inversion
 *
 *Inverses an affine matrix.\warning Results are undefined if the matrix is not an affine one
 *\param mx the matrix to inverse
 */
void gf_mx_inverse(GF_Matrix *mx);
/*!\brief matrix point transformation
 *
 *Applies a 3D matrix transformation to a 3D point
 *\param mx transformation matrix
 *\param pt pointer to 3D point. Once the function is called, pt contains the transformed point
*/
void gf_mx_apply_vec(GF_Matrix *mx, GF_Vec *pt);
/*!\brief matrix rectangle transformation
 *
 *Applies a 3D matrix transformation to a rectangle, giving the enclosing rectangle of the transformed one.\note all depth information are discarded.
 *\param _this transformation matrix
 *\param rc pointer to rectangle. Once the function is called, rc contains the transformed rectangle
*/
void gf_mx_apply_rect(GF_Matrix *_this, GF_Rect *rc);
/*!\brief ortho matrix construction
 *
 *Creates an orthogonal projection matrix
 *\param mx matrix to initialize
 *\param left min horizontal coordinate of viewport
 *\param right max horizontal coordinate of viewport
 *\param bottom min vertical coordinate of viewport
 *\param top max vertical coordinate of viewport
 *\param z_near min depth coordinate of viewport
 *\param z_far max depth coordinate of viewport
*/
void gf_mx_ortho(GF_Matrix *mx, Fixed left, Fixed right, Fixed bottom, Fixed top, Fixed z_near, Fixed z_far);
/*!\brief perspective matrix construction
 *
 *Creates a perspective projection matrix
 *\param mx matrix to initialize
 *\param foc camera field of view angle in radian
 *\param aspect_ratio viewport aspect ratio
 *\param z_near min depth coordinate of viewport
 *\param z_far max depth coordinate of viewport
*/
void gf_mx_perspective(GF_Matrix *mx, Fixed foc, Fixed aspect_ratio, Fixed z_near, Fixed z_far);
/*!\brief creates look matrix
 *
 *Creates a transformation matrix looking at a given direction from a given point (camera matrix).
 *\param mx matrix to initialize
 *\param position position
 *\param target look direction
 *\param up_vector vector describing the up direction
*/
void gf_mx_lookat(GF_Matrix *mx, GF_Vec position, GF_Vec target, GF_Vec up_vector);
/*!\brief matrix box transformation
 *
 *Applies a 3D matrix transformation to a bounding box, giving the enclosing box of the transformed one
 *\param mx transformation matrix
 *\param b pointer to bounding box. Once the function is called, contains the transformed bounding box
*/
void gf_mx_apply_bbox(GF_Matrix *mx, GF_BBox *b);
/*!\brief non-affine matrix multiplication
 *
 *Multiplies two non-affine matrices mx = mx*mul
*/
void gf_mx_add_matrix_4x4(GF_Matrix *mat, GF_Matrix *mul);
/*!\brief non-affine matrix inversion
 *
 *Inverses a non-affine matrices
 *\return 1 if inversion was done, 0 if inversion not possible.
*/
Bool gf_mx_inverse_4x4(GF_Matrix *mx);
/*!\brief matrix 4D vector transformation
 *
 *Applies a 3D non-affine matrix transformation to a 4 dimension vector
 *\param mx transformation matrix
 *\param vec pointer to the vector. Once the function is called, contains the transformed vector
*/
void gf_mx_apply_vec_4x4(GF_Matrix *mx, GF_Vec4 *vec);
/*!\brief matrix decomposition
 *
 *Decomposes a matrix into translation, scale, shear and rotate
 *\param mx the matrix to decompose
 *\param translate the decomposed translation part
 *\param scale the decomposed scaling part
 *\param rotate the decomposed rotation part, expressed as a Rotataion (axis + angle)
 *\param shear the decomposed shear part
 */
void gf_mx_decompose(GF_Matrix *mx, GF_Vec *translate, GF_Vec *scale, GF_Vec4 *rotate, GF_Vec *shear);
/*!\brief matrix vector rotation
 *
 *Rotates a vector with a given matrix, ignoring any translation.
 *\param mx transformation matrix
 *\param pt pointer to 3D vector. Once the function is called, pt contains the transformed vector
 */
void gf_mx_rotate_vector(GF_Matrix *mx, GF_Vec *pt);
/*!\brief matrix initialization from vectors
 *
 *Inits a matrix to rotate the local axis in the given vectors
 \param mx matrix to initialize
 \param x_axis target normalized X axis
 \param y_axis target normalized Y axis
 \param z_axis target normalized Z axis
*/
void gf_mx_rotation_matrix_from_vectors(GF_Matrix *mx, GF_Vec x_axis, GF_Vec y_axis, GF_Vec z_axis);
/*!\brief matrix to 2D matrix 
 *
 *Inits a 2D matrix by removing all depth info from a 3D matrix
 *\param mx2d 2D matrix to initialize
 *\param mx 3D matrix to use
*/
void gf_mx2d_from_mx(GF_Matrix2D *mx2d, GF_Matrix *mx);

/*!\brief Plane object*/
typedef struct
{
	/*!normal vector to the plane*/
	GF_Vec normal;
	/*!distance from origin of the plane*/
	Fixed d;
} GF_Plane;
/*!\brief matrix plane transformation
 *
 *Transorms a plane by a given matrix
 *\param mx the matrix to use
 *\param plane pointer to 3D plane. Once the function is called, plane contains the transformed plane
 */
void gf_mx_apply_plane(GF_Matrix *mx, GF_Plane *plane);
/*!\brief point to plane distance
 *
 *Gets the distance between a point and a plne
 *\param plane the plane to use
 *\param p pointer to ^point to check
 *\return the distance between the place and the point
 */
Fixed gf_plane_get_distance(GF_Plane *plane, GF_Vec *p);
/*!\brief closest point on a line
 *
 *Gets the closest point on a line from a given point in space
 *\param line_pt a point of the line to test
 *\param line_vec the normalized direction vector of the line
 *\param pt the point to check
 *\return the closest point on the line to the desired point
 */
GF_Vec gf_closest_point_to_line(GF_Vec line_pt, GF_Vec line_vec, GF_Vec pt);
/*!\brief box p-vertex index
 *
 *Gets the p-vertex index for a given plane. The p-vertex index is the index of the closest vertex of a bounding box to the plane. The vertices of a box are always 
 *ordered in GPAC? cf \ref gf_bbox_get_vertices
 *\param p the plane to check
 *\return the p-vertex index value, ranging from 0 to 7
*/
u32 gf_plane_get_p_vertex_idx(GF_Plane *p);
/*!\brief plane line intersection
 *
 *Checks for the intersection of a plane and a line
 *\param plane plane to test
 *\param linepoint a point on the line to test
 *\param linevec normalized direction vector of the line to test
 *\param outPoint optional pointer to retrieve the intersection point, NULL otherwise
 *\return 1 if line and plane intersect, 0 otherwise
*/
Bool gf_plane_intersect_line(GF_Plane *plane, GF_Vec *linepoint, GF_Vec *linevec, GF_Vec *outPoint);

/*!Classification types for box/plane position used in \ref gf_bbox_plane_relation*/
enum 
{	
	/*!box is in front of the plane*/
	GF_BBOX_FRONT,
	/*!box intersects the plane*/
	GF_BBOX_INTER,
	/*!box is back of the plane*/
	GF_BBOX_BACK
};
/*!\brief box-plane relation
 *
 *Gets the spatial relation between a box and a plane
 *\param box the box to check
 *\param p the plane to check
 *\return the relation type
 */
u32 gf_bbox_plane_relation(GF_BBox *box, GF_Plane *p);

/*!\brief 3D Ray
 *
 *The 3D ray object is used in GPAC for all collision and mouse interaction tests
*/
typedef struct
{
	/*!origin point of the ray*/
	GF_Vec orig;
	/*!normalized direction vector of the ray*/
	GF_Vec dir;
} GF_Ray;

/*!\brief ray constructor
 *
 *Constructs a ray object
 *\param start starting point of the ray
 *\param end end point of the ray, or any point on the ray
 *\return the ray object
*/
GF_Ray gf_ray(GF_Vec start, GF_Vec end);
/*!\brief matrix ray transformation
 *
 *Transforms a ray by a given transformation matrix
 *\param mx the matrix to use
 *\param r pointer to the ray. Once the function is called, contains the transformed ray
*/
void gf_mx_apply_ray(GF_Matrix *mx, GF_Ray *r);
/*!\brief ray box intersection test
 *
 *Checks if a ray intersects a box or not
 *\param ray the ray to check
 *\param min_edge the minimum edge of the box to check
 *\param max_edge the maximum edge of the box to check
 *\param out_point optional location of a 3D point to store the intersection, NULL otherwise.
 *\return retuns 1 if the ray intersects the box, 0 otherwise
*/
Bool gf_ray_hit_box(GF_Ray *ray, GF_Vec min_edge, GF_Vec max_edge, GF_Vec *out_point);
/*!\brief ray sphere intersection test
 *
 *Checks if a ray intersects a box or not
 *\param ray the ray to check
 *\param center the center of the sphere to check. If NULL, the origin (0,0,0)is used
 *\param radius the radius of the sphere to check
 *\param out_point optional location of a 3D point to store the intersection, NULL otherwise
 *\return retuns 1 if the ray intersects the sphere, 0 otherwise
*/
Bool gf_ray_hit_sphere(GF_Ray *ray, GF_Vec *center, Fixed radius, GF_Vec *out_point);
/*!\brief ray triangle intersection test
 *
 *Checks if a ray intersects a triangle or not
 *\param ray the ray to check
 *\param v0 first vertex of the triangle
 *\param v1 second vertex of the triangle
 *\param v2 third vertex of the triangle
 *\param dist optional location of a fixed number to store the intersection distance from ray origin if any, NULL otherwise
 *\return retuns 1 if the ray intersects the triangle, 0 otherwise
*/
Bool gf_ray_hit_triangle(GF_Ray *ray, GF_Vec *v0, GF_Vec *v1, GF_Vec *v2, Fixed *dist);
/*same as above and performs backface cull (solid meshes)*/
/*!\brief ray triangle intersection test
 *
 *Checks if a ray intersects a triangle or not, performing backface culling. For parameters details, look at \ref gf_ray_hit_triangle_backcull
 */
Bool gf_ray_hit_triangle_backcull(GF_Ray *ray, GF_Vec *v0, GF_Vec *v1, GF_Vec *v2, Fixed *dist);

/*! @} */

/*! @} */

#ifdef __cplusplus
}
#endif


#endif		/*_GF_MATH_H_*/