Lephisto/src/physics.h

53 lines
1.6 KiB
C

#pragma once
#include <math.h>
#define VX(v) ((v).x)
#define VY(v) ((v).y)
#define VMOD(v) ((v).mod)
#define VANGLE(v) ((v).angle)
#define MOD(x,y) (sqrt((x)*(x) + (y)*(y)))
#define ANGLE(x,y) (((x)==0.) ? 0. : atan2(y,x))
#define vect_dist(v,u) MOD((v)->x-(u)->x, (v)->y-(u)->y)
#define vect_odist(v) MOD((v)->x, (v)->y)
/* Base of 2D vectors. */
typedef struct Vec2_ {
double x, y; /* Cartesian values. */
double mod, angle; /* Polar values. */
} Vec2;
/* Misc */
double angle_diff(const double ref, double a);
void limit_speed(Vec2* vel, const double speed, const double dt);
/* Vector manupulation. */
void vect_cset(Vec2* v, const double x, const double y);
/* Doesn't set mod nor angle. */
void vect_csetmin(Vec2* v, const double x, const double y);
void vect_pset(Vec2* v, const double mod, const double angle);
void vectcpy(Vec2* dest, const Vec2* src);
void vectnull(Vec2* v);
double vect_angle(const Vec2* ref, const Vec2* v);
void vect_cadd(Vec2* v, const double x, const double y);
void vect_reflect(Vec2* r, Vec2* v, Vec2* n);
double vect_dot(Vec2* a, Vec2* b);
/* Describe any solid in 2D space. */
typedef struct Solid_ {
double mass, dir, dir_vel; /* Properties. */
Vec2 vel, pos, force; /* Position/velocity vectors. */
void(*update)(struct Solid_*, const double); /* Update method. */
} Solid;
/* Solid manipulation. */
void solid_init(Solid* dest, const double mass, const double dir,
const Vec2* pos, const Vec2* vel);
Solid* solid_create(const double mass, const double dir,
const Vec2* pos, const Vec2* vel);
void solid_free(Solid* src);