## rotate (`lygia`/`space`/`rotate`)

rotate a 2D space by a radian r

Dependencies:

Use:

``````rotate(<vec3|vec2> v, float r [, vec2 c])
``````

Check it on Github

``````

#ifndef FNC_ROTATE
#define FNC_ROTATE
vec2 rotate(in vec2 v, in float r, in vec2 c) {
return rotate2d(r) * (v - c) + c;
}

vec2 rotate(in vec2 v, in float r) {
#ifdef CENTER_2D
return rotate(v, r, CENTER_2D);
#else
return rotate(v, r, vec2(.5));
#endif
}

vec2 rotate(vec2 v, vec2 x_axis) {
#ifdef CENTER_2D
v -= CENTER_2D;
#endif
vec2 rta = vec2( dot(v, vec2(-x_axis.y, x_axis.x)), dot(v, x_axis) );
#ifdef CENTER_2D
rta += CENTER_2D;
#endif
return rta;
}

vec3 rotate(in vec3 v, in float r, in vec3 axis, in vec3 c) {
return (rotate4d(axis, r) * vec4(v - c, 1.)).xyz + c;
}

vec3 rotate(in vec3 v, in float r, in vec3 axis) {
#ifdef CENTER_3D
return rotate(v, r, axis, CENTER_3D);
#else
return rotate(v, r, axis, vec3(0.));
#endif
}

vec4 rotate(in vec4 v, in float r, in vec3 axis, in vec4 c) {
return rotate4d(axis, r) * (v - c) + c;
}

vec4 rotate(in vec4 v, in float r, in vec3 axis) {
#ifdef CENTER_4D
return rotate(v, r, axis, CENTER_4D);
#else
return rotate(v, r, axis, vec4(0.));
#endif
}

#if defined(FNC_QUATMULT)
vec3 rotate(QUAT q, vec3 v) {
QUAT q_c = QUAT(-q.x, -q.y, -q.z, q.w);
return quatMul(q, quatMul(vec4(v, 0), q_c)).xyz;
}

vec3 rotate(QUAT q, vec3 v, vec3 c) {
vec3 dir = v - c;
return c + rotate(q, dir);
}
#endif

#endif

``````

Dependencies:

Use:

``````rotate(<float3|float2> st, float radians [, float2 center])
``````

Check it on Github

``````

#ifndef FNC_ROTATE
#define FNC_ROTATE
float2 rotate(in float2 st, in float radians, in float2 center) {
return mul(rotate2d(radians), (st - center)) + center;
}

float2 rotate(in float2 st, in float radians) {
#ifdef CENTER_2D
#else
#endif
}

float2 rotate(float2 st, float2 x_axis) {
#ifdef CENTER_2D
st -= CENTER_2D;
#endif
float2 rta = float2( dot(st, float2(-x_axis.y, x_axis.x)), dot(st, x_axis) );
#ifdef CENTER_2D
rta += CENTER_2D;
#endif
return rta;
}

float3 rotate(in float3 xyz, in float radians, in float3 axis, in float3 center) {
return mul(rotate4d(axis, radians), float4(xyz - center, 1.)).xyz + center;
}

float3 rotate(in float3 xyz, in float radians, in float3 axis) {
#ifdef CENTER_3D
#else
return rotate(xyz, radians, axis, float3(0.0, 0.0, 0.0));
#endif
}

float4 rotate(in float4 xyzw, in float radians, in float3 axis, in float4 center) {
return mul(rotate4d(axis, radians), (xyzw - center)) + center;
}

float4 rotate(in float4 xyzw, in float radians, in float3 axis) {
#ifdef CENTER_4D
#else
return rotate(xyzw, radians, axis, float4(0.0, 0.0, 0.0, 0.0));
#endif
}
#endif

``````

Dependencies:

Check it on Github

``````

fn rotate(st: vec2f, radians: f32) -> vec2f {
return rotate2d(radians) * (st - 0.5) + 0.5;
}

``````