#define _MAT_VARIANT1(NEW_NAME, BASE_FN, TYPE_1, ARG_1) \
	SurfacePoint NEW_NAME(float3 p, TYPE_1 ARG_1, Material mat = DEFAULT_MAT) {\
		SurfacePoint o;\
		o.dist = BASE_FN(p, ARG_1);\
		o.mat = mat;\
		return o;\
	}

#define _MAT_VARIANT2(NEW_NAME, BASE_FN, TYPE_1, ARG_1, TYPE_2, ARG_2) \
	SurfacePoint NEW_NAME(float3 p, TYPE_1 ARG_1, TYPE_2 ARG_2, Material mat = DEFAULT_MAT) {\
		SurfacePoint o;\
		o.dist = BASE_FN(p, ARG_1, ARG_2);\
		o.mat = mat;\
		return o;\
	}

#define _MAT_VARIANT3(NEW_NAME, BASE_FN, TYPE_1, ARG_1, TYPE_2, ARG_2, TYPE_3, ARG_3) \
	SurfacePoint NEW_NAME(float3 p, TYPE_1 ARG_1, TYPE_2 ARG_2, TYPE_3 ARG_3, Material mat = DEFAULT_MAT) {\
		SurfacePoint o;\
		o.dist = BASE_FN(p, ARG_1, ARG_2, ARG_3);\
		o.mat = mat;\
		return o;\
	}

//
// Most of these are taken from https://iquilezles.org/articles/distfunctions/
// Thank you Inigo Quilez <3

float sdBox(float3 p, float3 size) {
	float3 q = abs(p) - size / 2.0;
	return length(max(q, 0)) + min(max(q.x, max(q.y, q.z)), 0);
}
_MAT_VARIANT1(mBox, sdBox, float3, size)

float sdSphere(float3 p, float radius) {
	return length(p) - radius;
}
_MAT_VARIANT1(mSphere, sdSphere, float, radius)

float sdTorus(float3 p, float radius, float thickness) {
	float2 q = float2(length(p.xz) - radius, p.y);
	return length(q) - thickness;
}
_MAT_VARIANT2(mTorus, sdTorus, float, radius, float, thickness)

float sdPlaneY(float3 p, float height) {
	return p.y - height;
}
_MAT_VARIANT1(mPlaneY, sdPlaneY, float, height)

float sdHexPrism(float3 p, float width, float height) {
  const float3 k = float3(-0.8660254, 0.5, 0.57735);
  p = abs(p);
  p.xz -= 2.0 * min(dot(k.xy, p.xz), 0) * k.xy;
  float2 d = float2(length(p.xz - float2(clamp(p.x,-k.z * width, k.z * width), width)) * sign(p.z - width), p.y - height);
  return min(max(d.x, d.y), 0) + length(max(d, 0));
}
_MAT_VARIANT2(mHexPrism, sdHexPrism, float, width, float, height)

float sdInfCylinder(float3 p, float3 c) {
	return length(p.xz - c.xy) - c.z;
}
_MAT_VARIANT1(mInfCylinder, sdInfCylinder, float3, c)

float sdCylinder(float3 p, float r, float h) {
	float2 d = abs(float2(length(p.xz), p.y)) - float2(r, h);
	return min(max(d.x, d.y), 0) + length(max(d, 0));
}
_MAT_VARIANT2(mCylinder, sdCylinder, float, r, float, h)

float sdHelix(float3 p, float r1, float r2, float incline) {
	float x2 = length(p.xz) - r1; // vertical plane
	float angle = atan2(p.z, p.x); // angle around y axis
	float y = angle * incline - p.y;
	y = fmod(y, UNITY_PI * incline * 2) + UNITY_PI * incline;
	return length(float2(x2, y)) - r2;
}
_MAT_VARIANT3(mHelix, sdHelix, float, r1, float, r2, float, incline)

float sdLine(float3 p, float3 a, float3 b, float r) {
	float3 pa = p - a;
	float3 ba = b - a;
	float h = clamp(dot(pa, ba) / dot(ba, ba), 0, 1);
	return length(p- a - (b-a) * h) - r;
}
_MAT_VARIANT3(mLine, sdLine, float3, a, float3, b, float3, r)


SurfacePoint mDummy(float d, Material mat = DEFAULT_MAT) {
	SurfacePoint o;
	o.dist = d;
	o.mat = mat;
	return o;
}