diff -r 02f142b399b1 -r 94c92c923713 src/geometry.h
--- a/src/geometry.h	Sat Jul 24 01:50:38 2021 +0300
+++ b/src/geometry.h	Sun Jul 25 13:49:37 2021 +0300
@@ -103,10 +103,31 @@
 		std::vector<glm::vec3> points;
 	};
 
-	inline bool isclose(const glm::vec3& a, const glm::vec3& b)
+	inline constexpr bool isclose(const glm::vec3& a, const glm::vec3& b)
 	{
 		return qFuzzyCompare(a.x, b.x)
 			and qFuzzyCompare(a.y, b.y)
 			and qFuzzyCompare(a.z, b.z);
 	}
+
+	struct CircleF
+	{
+		QPointF center;
+		qreal radius;
+	};
+
+	/**
+	 * @param center
+	 * @param radius
+	 * @returns a QRectF that encloses the specified circle
+	 */
+	inline constexpr QRectF inscribe(const CircleF& circle)
+	{
+		return {
+			circle.center.x() - circle.radius,
+			circle.center.y() - circle.radius,
+			circle.radius * 2,
+			circle.radius * 2
+		};
+	}
 }