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#ifndef _RAY_3F_H
#define _RAY_3F_H
#include <math.h>
typedef struct ray_3f_t {
float x, y, z;
} ray_3f_t;
/* return the result of (a + b) */
static inline ray_3f_t ray_3f_add(const ray_3f_t *a, const ray_3f_t *b)
{
ray_3f_t res = {
.x = a->x + b->x,
.y = a->y + b->y,
.z = a->z + b->z,
};
return res;
}
/* return the result of (a - b) */
static inline ray_3f_t ray_3f_sub(const ray_3f_t *a, const ray_3f_t *b)
{
ray_3f_t res = {
.x = a->x - b->x,
.y = a->y - b->y,
.z = a->z - b->z,
};
return res;
}
/* return the result of (-v) */
static inline ray_3f_t ray_3f_negate(const ray_3f_t *v)
{
ray_3f_t res = {
.x = -v->x,
.y = -v->y,
.z = -v->z,
};
return res;
}
/* return the result of (a * b) */
static inline ray_3f_t ray_3f_mult(const ray_3f_t *a, const ray_3f_t *b)
{
ray_3f_t res = {
.x = a->x * b->x,
.y = a->y * b->y,
.z = a->z * b->z,
};
return res;
}
/* return the result of (v * scalar) */
static inline ray_3f_t ray_3f_mult_scalar(const ray_3f_t *v, float scalar)
{
ray_3f_t res = {
.x = v->x * scalar,
.y = v->y * scalar,
.z = v->z * scalar,
};
return res;
}
/* return the result of (uv / scalar) */
static inline ray_3f_t ray_3f_div_scalar(const ray_3f_t *v, float scalar)
{
ray_3f_t res = {
.x = v->x / scalar,
.y = v->y / scalar,
.z = v->z / scalar,
};
return res;
}
/* return the result of (a . b) */
static inline float ray_3f_dot(const ray_3f_t *a, const ray_3f_t *b)
{
return a->x * b->x + a->y * b->y + a->z * b->z;
}
/* return the length of the supplied vector */
static inline float ray_3f_length(const ray_3f_t *v)
{
return sqrtf(ray_3f_dot(v, v));
}
/* return the normalized form of the supplied vector */
static inline ray_3f_t ray_3f_normalize(const ray_3f_t *v)
{
return ray_3f_mult_scalar(v, 1.0f / ray_3f_length(v));
}
/* return the distance between two arbitrary points */
static inline float ray_3f_distance(const ray_3f_t *a, const ray_3f_t *b)
{
ray_3f_t delta = ray_3f_sub(a, b);
return ray_3f_length(&delta);
}
/* return the cross product of two unit vectors */
static inline ray_3f_t ray_3f_cross(const ray_3f_t *a, const ray_3f_t *b)
{
ray_3f_t product;
product.x = a->y * b->z - a->z * b->y;
product.y = a->z * b->x - a->x * b->z;
product.z = a->x * b->y - a->y * b->x;
return product;
}
/* return the linearly interpolated vector between the two vectors at point alpha (0-1.0) */
static inline ray_3f_t ray_3f_lerp(const ray_3f_t *a, const ray_3f_t *b, float alpha)
{
ray_3f_t lerp_a, lerp_b;
lerp_a = ray_3f_mult_scalar(a, 1.0f - alpha);
lerp_b = ray_3f_mult_scalar(b, alpha);
return ray_3f_add(&lerp_a, &lerp_b);
}
/* return the normalized linearly interpolated vector between the two vectors at point alpha (0-1.0) */
static inline ray_3f_t ray_3f_nlerp(const ray_3f_t *a, const ray_3f_t *b, float alpha)
{
ray_3f_t lerp;
lerp = ray_3f_lerp(a, b, alpha);
return ray_3f_normalize(&lerp);
}
#endif
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