From bb0773320c101f253d64c2c9d4e6aab874348bef Mon Sep 17 00:00:00 2001
From: Tomas Maly <malytomas@ucpu.cz>
Date: Sat, 27 Jan 2024 03:52:33 +0100
Subject: [PATCH] hemispheres

---
 sources/modesConfiguration.cpp |  4 ++++
 sources/sdf.cpp                | 16 ++++++++++++++++
 sources/sdf.h                  |  1 +
 3 files changed, 21 insertions(+)

diff --git a/sources/modesConfiguration.cpp b/sources/modesConfiguration.cpp
index 6f99ff0..e52db47 100644
--- a/sources/modesConfiguration.cpp
+++ b/sources/modesConfiguration.cpp
@@ -52,6 +52,7 @@ namespace unnatural
 				&sdfH2O,
 				&sdfH3O,
 				&sdfH4O,
+				&sdfHemispheres,
 				&sdfHexagon,
 				&sdfHexagonalPrism,
 				&sdfInsideCube,
@@ -89,6 +90,7 @@ namespace unnatural
 				"h2o",
 				"h3o",
 				"h4o",
+				"hemispheres",
 				"hexagon",
 				"hexagonalprism",
 				"insidecube",
@@ -138,6 +140,8 @@ namespace unnatural
 					return true;
 				if (name == "bowl")
 					return true;
+				if (name == "hemispheres")
+					return true;
 				if (name == "hexagon")
 					return true;
 				if (name == "insidecube")
diff --git a/sources/sdf.cpp b/sources/sdf.cpp
index 21d1764..e46b837 100644
--- a/sources/sdf.cpp
+++ b/sources/sdf.cpp
@@ -379,4 +379,20 @@ namespace unnatural
 			return sdfCylinder(Vec3(p[0], p[2], p[1]), 10000, Radius) * -1;
 		return Radius - abs(p[2]);
 	}
+
+	Real sdfHemispheres(const Vec3 &p_)
+	{
+		const Vec3 p = Vec3(abs(p_[0]), abs(p_[1]), p_[2]);
+		const auto &rotate = [](Vec3 p) -> Vec3
+		{
+			static constexpr Real s = 0.707106781186547524400844362104; // sin(45)
+			return Vec3((p[0] - p[1]) * s, (p[0] + p[1]) * s, p[2]);
+		};
+		const Vec3 q = rotate(p + Vec3(-2000, 0, 0));
+		const Real c = sdfCylinder(Vec3(q[1], q[2], q[0]), 10000, 200);
+		const Real s1 = sdfSphere(q, 1000);
+		const Real s2 = sdfSphere(rotate(p + Vec3(0, -2000, 0)), 1000);
+		const Real s = min(s1, s2);
+		return smoothMin(c, s, 100);
+	}
 }
diff --git a/sources/sdf.h b/sources/sdf.h
index 962f742..c78c54f 100644
--- a/sources/sdf.h
+++ b/sources/sdf.h
@@ -21,6 +21,7 @@ namespace unnatural
 	Real sdfH2O(const Vec3 &pos);
 	Real sdfH3O(const Vec3 &pos);
 	Real sdfH4O(const Vec3 &pos);
+	Real sdfHemispheres(const Vec3 &p);
 	Real sdfHexagon(const Vec3 &pos);
 	Real sdfHexagonalPrism(const Vec3 &pos);
 	Real sdfInsideCube(const Vec3 &p);