diff --git a/include/Geometry.h b/include/Geometry.h
index 57b38f20..85009bcc 100644
--- a/include/Geometry.h
+++ b/include/Geometry.h
@@ -7,23 +7,23 @@
 struct Sphere;
 
 /**
- * @brief TODO
+ * @brief A representation of a cylinder in 3D space.
  */
 struct Cylinder {
-	Cylinder(Vector3f& p1, Vector3f& p2, f32 p3)
-	    : _00(p1)
-	    , _0C(p2)
-	    , _18(p3)
+	Cylinder(Vector3f& startPoint, Vector3f& endPoint, f32 radius)
+	    : mStartPoint(startPoint)
+	    , mEndPoint(endPoint)
+	    , mRadius(radius)
 	{
 	}
 
-	void get2dDist(Vector3f&);
-	void collide(const Sphere&, Vector3f&, f32&);
-	f32 getPosRatio(const Vector3f&);
+	f32 get2dDist(Vector3f& point);
+	void collide(const Sphere& sphere, Vector3f& point, f32& depth);
+	f32 getPosRatio(const Vector3f& point); // 0-1 along the cylinder axis
 
-	Vector3f _00; // _00
-	Vector3f _0C; // _0C
-	f32 _18;      // _18
+	Vector3f mStartPoint; // _00
+	Vector3f mEndPoint;   // _0C
+	f32 mRadius;          // _18
 };
 
 /**
diff --git a/src/plugPikiKando/collInfo.cpp b/src/plugPikiKando/collInfo.cpp
index 740f63b9..f71aec56 100644
--- a/src/plugPikiKando/collInfo.cpp
+++ b/src/plugPikiKando/collInfo.cpp
@@ -38,8 +38,34 @@ static char* _typeStr[] = {
  * Address:	80086CC4
  * Size:	0002DC
  */
-void Cylinder::get2dDist(Vector3f&)
+f32 Cylinder::get2dDist(Vector3f& point)
 {
+	// Calculate cylinder direction vector
+	Vector3f cylinderDir = mEndPoint - mStartPoint;
+
+	Vector3f normalised = cylinderDir;
+
+	// Project point onto cylinder axis
+	f32 length          = normalised.normalise();
+	f32 projectionRatio = normalised.DP(point - mStartPoint) / length;
+
+	if (projectionRatio < 0.0f) {
+		// Before cylinder start - get 2D distance to start point
+		Vector3f startToPoint = mStartPoint - point;
+		return sqrtf(startToPoint.x * startToPoint.x + startToPoint.z * startToPoint.z);
+	}
+
+	if (projectionRatio > 1.0f) {
+		// Past cylinder end - get 2D distance to end point
+		Vector3f endToPoint = mEndPoint - point;
+		return sqrtf(endToPoint.x * endToPoint.x + endToPoint.z * endToPoint.z);
+	}
+
+	// On cylinder body - get distance to projected point
+	Vector3f projectedPoint = (normalised * projectionRatio) + mStartPoint;
+	Vector3f projToPoint    = projectedPoint - point;
+	return sqrtf(projToPoint.x * projToPoint.x + projToPoint.z * projToPoint.z);
+
 	/*
 	.loc_0x0:
 	  mflr      r0
@@ -761,7 +787,7 @@ bool Tube::collide(const Sphere&, Vector3f&, f32&)
  * Address:	800876C8
  * Size:	0000E4
  */
-f32 Cylinder::getPosRatio(const Vector3f&)
+f32 Cylinder::getPosRatio(const Vector3f& vec)
 {
 	/*
 	.loc_0x0: