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ninijo/cquat.h

Created Feb 11, 2018
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vector/quaternion math library
#ifndef CQUAT_H
#define CQUAT_H
#include <complex.h>
#define sqr(x) x*x
typedef struct {
float x,y;
} vec2;
typedef struct {
float x,y,z;
} vec3;
typedef struct {
float x, y, z, w;
} vec4;
vec2 add_vec2(vec2 v1, vec2 v2) {
return (vec2){v1.x + v2.x, v1.y + v2.y};
}
vec3 add_vec3(vec3 v1, vec3 v2) {
return (vec3){v1.x + v2.x, v1.y + v2.y, v1.z + v2.z};
}
vec4 add_vec4(vec4 v1, vec4 v2) {
return (vec4){v1.x + v2.x, v1.y + v2.y, v1.z + v2.z, v1.w + v2.w};
}
vec2 subtract_vec2(vec2 v1, vec2 v2) {
return (vec2){v1.x - v2.x, v1.y - v2.y};
}
vec3 subtract_vec3(vec3 v1, vec3 v2) {
return (vec3){v1.x - v2.x, v1.y - v2.y, v1.z - v2.z};
}
vec4 subtract_vec4(vec4 v1, vec4 v2) {
return (vec4){v1.x - v2.x, v1.y - v2.y, v1.z - v2.z, v1.w - v2.w};
}
vec2 mul_vec2(vec2 v, float s) {
return (vec2){v.x * s, v.y * s};
}
vec3 mul_vec3(vec3 v, float s) {
return (vec3){v.x * s, v.y * s, v.z * s};
}
vec4 mul_vec4(vec4 v, float s) {
return (vec4){v.x * s, v.y * s, v.z * s, v.w * s};
}
vec2 div_vec2(vec2 v, float s) {
return (vec2){v.x / s, v.y / s};
}
vec3 div_vec3(vec3 v, float s) {
return (vec3){v.x / s, v.y / s, v.z / s};
}
vec4 div_vec4(vec4 v, float s) {
return (vec4){v.x / s, v.y / s, v.z / s, v.w / s};
}
float length_vec2(const vec2* v) {
return sqrtf(sqr(v->x) + sqr(v->y));
}
float length_vec3(const vec3* v) {
return sqrtf(sqr(v->x) + sqr(v->y) + sqr(v->z));
}
float length_vec4(const vec4* v) {
return sqrtf(sqr(v->x) + sqr(v->y) + sqr(v->z) + sqr(v->w));
}
void normalize_vec2(vec2* v) {
float l = length_vec2(v);
v->x/=l, v->y/=l;
}
void normalize_vec3(vec3* v) {
float l = length_vec3(v);
v->x/=l, v->y/=l, v->z/=l;
}
void normalize_vec4(vec4* v) {
float l = length_vec4(v);
v->x/=l, v->y/=l, v->z/=l, v->w/=l;
}
void rotate_vec2(vec2* v, float theta) {
float complex v0 = v->x + v->y * I;
float complex rot = cosf(theta) + sinf(theta) * I;
float complex v1 = rot*v0;
v->x = crealf(v1), v->y = cimagf(v1);
}
void rotate_vec3(vec3* v, float theta) {
}
vec4 quat_mult(vec4 q1, vec4 q2) {
return (vec4) {q1.x * q2.w + q1.y * q2.z - q1.z * q2.y + q1.w * q2.x,
-q1.x * q2.z + q1.y * q2.w + q1.z * q2.x + q1.w * q2.y,
q1.x * q2.y - q1.y * q2.x + q1.z * q2.w + q1.w * q2.z,
-q1.x * q2.x - q1.y * q2.y - q1.z * q2.z + q1.w * q2.w};
}
vec4 quat_conjugate(vec4 q) {
return (vec4) {-q.x, -q.y, -q.z, q.w};
}
#endif //CQUAT_H
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