static Vector3[] vertices = null; // TODO: store this per instance? or just allocate every frame?

        protected override void OnScene(ChiselCapsule generator)
        {
            var baseColor    = UnityEditor.Handles.yAxisColor;
            var isDisabled   = UnitySceneExtensions.SceneHandles.disabled;
            var focusControl = UnitySceneExtensions.SceneHandleUtility.focusControl;
            var normal       = Vector3.up;

            if (!BrushMeshFactory.GenerateCapsuleVertices(ref generator.definition, ref vertices))
            {
                return;
            }

            UnityEditor.Handles.color = ChiselCylinderEditor.GetColorForState(baseColor, false, false, isDisabled);
            DrawOutline(generator.definition, vertices, lineMode: LineMode.ZTest);

            UnityEditor.Handles.color = ChiselCylinderEditor.GetColorForState(baseColor, false, true, isDisabled);
            DrawOutline(generator.definition, vertices, lineMode: LineMode.NoZTest);


            var topLoopID    = GUIUtility.GetControlID(s_TopLoopHash, FocusType.Keyboard);
            var bottomLoopID = GUIUtility.GetControlID(s_BottomLoopHash, FocusType.Keyboard);


            var topPoint    = normal * (generator.definition.offsetY + generator.Height);
            var bottomPoint = normal * (generator.definition.offsetY);
            var middlePoint = normal * (generator.definition.offsetY + (generator.Height * 0.5f));
            var radius2D    = new Vector2(generator.definition.diameterX, generator.definition.diameterZ) * 0.5f;

            var topHeight    = generator.definition.topHeight;
            var bottomHeight = generator.definition.bottomHeight;

            var maxTopHeight    = generator.definition.height - bottomHeight;
            var maxBottomHeight = generator.definition.height - topHeight;

            if (generator.Height < 0)
            {
                normal = -normal;
            }

            EditorGUI.BeginChangeCheck();
            {
                UnityEditor.Handles.color = baseColor;
                // TODO: make it possible to (optionally) size differently in x & z
                radius2D.x = UnitySceneExtensions.SceneHandles.RadiusHandle(normal, middlePoint, radius2D.x);

                var topId = GUIUtility.GetControlID(s_TopHash, FocusType.Passive);
                {
                    var isTopBackfaced = ChiselCylinderEditor.IsSufaceBackFaced(topPoint, normal);
                    var topHasFocus    = (focusControl == topId);

                    UnityEditor.Handles.color = ChiselCylinderEditor.GetColorForState(baseColor, topHasFocus, isTopBackfaced, isDisabled);
                    topPoint = UnitySceneExtensions.SceneHandles.DirectionHandle(topId, topPoint, normal);

                    var topLoopHasFocus = (topHasFocus && !generator.HaveRoundedTop) || (focusControl == topLoopID);

                    var thickness = topLoopHasFocus ? kCapLineThicknessSelected : kCapLineThickness;

                    UnityEditor.Handles.color = ChiselCylinderEditor.GetColorForState(baseColor, topLoopHasFocus, true, isDisabled);
                    ChiselOutlineRenderer.DrawLineLoop(vertices, generator.definition.topVertexOffset, generator.definition.sides, lineMode: LineMode.NoZTest, thickness: thickness);

                    UnityEditor.Handles.color = ChiselCylinderEditor.GetColorForState(baseColor, topLoopHasFocus, false, isDisabled);
                    ChiselOutlineRenderer.DrawLineLoop(vertices, generator.definition.topVertexOffset, generator.definition.sides, lineMode: LineMode.ZTest, thickness: thickness);

                    {
                        var prevGUIChanged = GUI.changed;
                        for (int j = generator.definition.sides - 1, i = 0; i < generator.definition.sides; j = i, i++)
                        {
                            GUI.changed = false;
                            var from       = vertices[j + generator.definition.topVertexOffset];
                            var to         = vertices[i + generator.definition.topVertexOffset];
                            var edgeOffset = UnitySceneExtensions.SceneHandles.Edge1DHandleOffset(topLoopID, UnitySceneExtensions.Axis.Y, from, to, capFunction: null);
                            if (GUI.changed)
                            {
                                topHeight      = Mathf.Clamp(topHeight - edgeOffset, 0, maxTopHeight);
                                prevGUIChanged = true;
                            }
                        }
                        GUI.changed = prevGUIChanged;
                    }
                }

                var bottomId = GUIUtility.GetControlID(s_BottomHash, FocusType.Passive);
                {
                    var isBottomBackfaced = ChiselCylinderEditor.IsSufaceBackFaced(bottomPoint, -normal);
                    var bottomHasFocus    = (focusControl == bottomId);

                    UnityEditor.Handles.color = ChiselCylinderEditor.GetColorForState(baseColor, bottomHasFocus, isBottomBackfaced, isDisabled);
                    bottomPoint = UnitySceneExtensions.SceneHandles.DirectionHandle(bottomId, bottomPoint, -normal);

                    var bottomLoopHasFocus = (bottomHasFocus && !generator.HaveRoundedBottom) || (focusControl == bottomLoopID);

                    var thickness = bottomLoopHasFocus ? kCapLineThicknessSelected : kCapLineThickness;

                    UnityEditor.Handles.color = ChiselCylinderEditor.GetColorForState(baseColor, bottomLoopHasFocus, true, isDisabled);
                    ChiselOutlineRenderer.DrawLineLoop(vertices, generator.definition.bottomVertexOffset, generator.definition.sides, lineMode: LineMode.NoZTest, thickness: thickness);

                    UnityEditor.Handles.color = ChiselCylinderEditor.GetColorForState(baseColor, bottomLoopHasFocus, false, isDisabled);
                    ChiselOutlineRenderer.DrawLineLoop(vertices, generator.definition.bottomVertexOffset, generator.definition.sides, lineMode: LineMode.ZTest, thickness: thickness);

                    {
                        var prevGUIChanged = GUI.changed;
                        for (int j = generator.definition.sides - 1, i = 0; i < generator.definition.sides; j = i, i++)
                        {
                            GUI.changed = false;
                            var from       = vertices[j + generator.definition.bottomVertexOffset];
                            var to         = vertices[i + generator.definition.bottomVertexOffset];
                            var edgeOffset = UnitySceneExtensions.SceneHandles.Edge1DHandleOffset(bottomLoopID, UnitySceneExtensions.Axis.Y, from, to, capFunction: null);
                            if (GUI.changed)
                            {
                                bottomHeight   = Mathf.Clamp(bottomHeight + edgeOffset, 0, maxBottomHeight);
                                prevGUIChanged = true;
                            }
                        }
                        GUI.changed = prevGUIChanged;
                    }
                }
            }
            if (EditorGUI.EndChangeCheck())
            {
                Undo.RecordObject(target, "Modified " + generator.NodeTypeName);
                generator.definition.diameterX    = radius2D.x * 2.0f;
                generator.definition.height       = topPoint.y - bottomPoint.y;
                generator.definition.diameterZ    = radius2D.x * 2.0f;
                generator.definition.offsetY      = bottomPoint.y;
                generator.definition.topHeight    = topHeight;
                generator.definition.bottomHeight = bottomHeight;
                generator.OnValidate();
                // TODO: handle sizing down (needs to modify transformation?)
            }
        }
        protected override void OnScene(ChiselStadium generator)
        {
            var baseColor     = UnityEditor.Handles.yAxisColor;
            var isDisabled    = UnitySceneExtensions.SceneHandles.disabled;
            var focusControl  = UnitySceneExtensions.SceneHandleUtility.focusControl;
            var upVector      = Vector3.up;
            var rightVector   = Vector3.right;
            var forwardVector = Vector3.forward;

            Vector3[] vertices = null;
            if (!BrushMeshFactory.GenerateStadiumVertices(generator.definition, ref vertices))
            {
                return;
            }


            UnityEditor.Handles.color = ChiselCylinderEditor.GetColorForState(baseColor, false, false, isDisabled);
            DrawOutline(generator.definition, vertices, lineMode: LineMode.ZTest);

            UnityEditor.Handles.color = ChiselCylinderEditor.GetColorForState(baseColor, false, true, isDisabled);
            DrawOutline(generator.definition, vertices, lineMode: LineMode.NoZTest);

            var height   = generator.definition.height;
            var length   = generator.definition.length;
            var diameter = generator.definition.diameter;
            var sides    = generator.definition.sides;

            var firstTopSide    = generator.definition.firstTopSide;
            var lastTopSide     = generator.definition.lastTopSide;
            var firstBottomSide = generator.definition.firstBottomSide;
            var lastBottomSide  = generator.definition.lastBottomSide;

            var haveRoundedTop    = generator.definition.haveRoundedTop;
            var haveRoundedBottom = generator.definition.haveRoundedBottom;
            var haveCenter        = generator.definition.haveCenter;
            var topLength         = generator.definition.topLength;
            var bottomLength      = generator.definition.bottomLength;


            var midY       = height * 0.5f;
            var halfLength = length * 0.5f;
            var midZ       = ((halfLength - (haveRoundedTop ? topLength : 0)) - (halfLength - (haveRoundedBottom ? bottomLength : 0))) * -0.5f;
            //	haveCenter ? ((vertices[firstTopSide].z + vertices[firstBottomSide].z) * 0.5f) : 0;

            var topPoint    = new Vector3(0, height, midZ);
            var bottomPoint = new Vector3(0, 0, midZ);
            var frontPoint  = new Vector3(0, midY, halfLength);
            var backPoint   = new Vector3(0, midY, -halfLength);
            var leftPoint   = new Vector3(diameter * 0.5f, midY, midZ);
            var rightPoint  = new Vector3(diameter * -0.5f, midY, midZ);

            EditorGUI.BeginChangeCheck();
            {
                var topId = GUIUtility.GetControlID(s_TopHash, FocusType.Passive);
                {
                    var isTopBackfaced = ChiselCylinderEditor.IsSufaceBackFaced(topPoint, upVector);
                    var topHasFocus    = (focusControl == topId);

                    UnityEditor.Handles.color = ChiselCylinderEditor.GetColorForState(baseColor, topHasFocus, isTopBackfaced, isDisabled);
                    topPoint = UnitySceneExtensions.SceneHandles.DirectionHandle(topId, topPoint, upVector);
                    //if (generator.definition.haveRoundedTop)
                    {
                        var thickness = topHasFocus ? kCapLineThicknessSelected : kCapLineThickness;

                        UnityEditor.Handles.color = ChiselCylinderEditor.GetColorForState(baseColor, topHasFocus, true, isDisabled);
                        ChiselOutlineRenderer.DrawLineLoop(vertices, sides, sides, lineMode: LineMode.NoZTest, thickness: thickness);
                        if (haveRoundedTop)
                        {
                            ChiselOutlineRenderer.DrawLine(vertices[sides + firstTopSide], vertices[sides + lastTopSide], lineMode: LineMode.NoZTest, thickness: kVertLineThickness);
                        }
                        if (haveRoundedBottom && haveCenter)
                        {
                            ChiselOutlineRenderer.DrawLine(vertices[sides + firstBottomSide], vertices[sides + lastBottomSide], lineMode: LineMode.NoZTest, thickness: kVertLineThickness);
                        }

                        UnityEditor.Handles.color = ChiselCylinderEditor.GetColorForState(baseColor, topHasFocus, false, isDisabled);
                        ChiselOutlineRenderer.DrawLineLoop(vertices, sides, sides, lineMode: LineMode.ZTest, thickness: thickness);
                        if (haveRoundedTop)
                        {
                            ChiselOutlineRenderer.DrawLine(vertices[sides + firstTopSide], vertices[sides + lastTopSide], lineMode: LineMode.ZTest, thickness: kVertLineThickness);
                        }
                        if (haveRoundedBottom && haveCenter)
                        {
                            ChiselOutlineRenderer.DrawLine(vertices[sides + firstBottomSide], vertices[sides + lastBottomSide], lineMode: LineMode.ZTest, thickness: kVertLineThickness);
                        }
                    }
                }

                var bottomId = GUIUtility.GetControlID(s_BottomHash, FocusType.Passive);
                {
                    var isBottomBackfaced = ChiselCylinderEditor.IsSufaceBackFaced(bottomPoint, -upVector);
                    var bottomHasFocus    = (focusControl == bottomId);

                    UnityEditor.Handles.color = ChiselCylinderEditor.GetColorForState(baseColor, bottomHasFocus, isBottomBackfaced, isDisabled);
                    bottomPoint = UnitySceneExtensions.SceneHandles.DirectionHandle(bottomId, bottomPoint, -upVector);
                    //if (haveRoundedBottom)
                    {
                        var thickness = bottomHasFocus ? kCapLineThicknessSelected : kCapLineThickness;

                        UnityEditor.Handles.color = ChiselCylinderEditor.GetColorForState(baseColor, bottomHasFocus, true, isDisabled);
                        ChiselOutlineRenderer.DrawLineLoop(vertices, 0, sides, lineMode: LineMode.NoZTest, thickness: thickness);
                        if (haveRoundedTop)
                        {
                            ChiselOutlineRenderer.DrawLine(vertices[firstTopSide], vertices[lastTopSide], lineMode: LineMode.NoZTest, thickness: kVertLineThickness);
                        }
                        if (haveRoundedBottom && haveCenter)
                        {
                            ChiselOutlineRenderer.DrawLine(vertices[firstBottomSide], vertices[lastBottomSide], lineMode: LineMode.NoZTest, thickness: kVertLineThickness);
                        }

                        UnityEditor.Handles.color = ChiselCylinderEditor.GetColorForState(baseColor, bottomHasFocus, false, isDisabled);
                        ChiselOutlineRenderer.DrawLineLoop(vertices, 0, sides, lineMode: LineMode.ZTest, thickness: thickness);
                        if (haveRoundedTop)
                        {
                            ChiselOutlineRenderer.DrawLine(vertices[firstTopSide], vertices[lastTopSide], lineMode: LineMode.ZTest, thickness: kVertLineThickness);
                        }
                        if (haveRoundedBottom && haveCenter)
                        {
                            ChiselOutlineRenderer.DrawLine(vertices[firstBottomSide], vertices[lastBottomSide], lineMode: LineMode.ZTest, thickness: kVertLineThickness);
                        }
                    }
                }

                var frontId = GUIUtility.GetControlID(s_TopHash, FocusType.Passive);
                {
                    var isTopBackfaced = ChiselCylinderEditor.IsSufaceBackFaced(frontPoint, forwardVector);
                    var frontHasFocus  = (focusControl == frontId);

                    UnityEditor.Handles.color = ChiselCylinderEditor.GetColorForState(baseColor, frontHasFocus, isTopBackfaced, isDisabled);
                    frontPoint = UnitySceneExtensions.SceneHandles.DirectionHandle(frontId, frontPoint, forwardVector);
                }

                var backId = GUIUtility.GetControlID(s_BottomHash, FocusType.Passive);
                {
                    var isBottomBackfaced = ChiselCylinderEditor.IsSufaceBackFaced(backPoint, -forwardVector);
                    var backHasFocus      = (focusControl == backId);

                    UnityEditor.Handles.color = ChiselCylinderEditor.GetColorForState(baseColor, backHasFocus, isBottomBackfaced, isDisabled);
                    backPoint = UnitySceneExtensions.SceneHandles.DirectionHandle(backId, backPoint, -forwardVector);
                }

                var leftId = GUIUtility.GetControlID(s_TopHash, FocusType.Passive);
                {
                    var isTopBackfaced = ChiselCylinderEditor.IsSufaceBackFaced(leftPoint, rightVector);
                    var leftHasFocus   = (focusControl == leftId);

                    UnityEditor.Handles.color = ChiselCylinderEditor.GetColorForState(baseColor, leftHasFocus, isTopBackfaced, isDisabled);
                    leftPoint = UnitySceneExtensions.SceneHandles.DirectionHandle(leftId, leftPoint, rightVector);
                }

                var rightId = GUIUtility.GetControlID(s_BottomHash, FocusType.Passive);
                {
                    var isBottomBackfaced = ChiselCylinderEditor.IsSufaceBackFaced(rightPoint, -rightVector);
                    var rightHasFocus     = (focusControl == rightId);

                    UnityEditor.Handles.color = ChiselCylinderEditor.GetColorForState(baseColor, rightHasFocus, isBottomBackfaced, isDisabled);
                    rightPoint = UnitySceneExtensions.SceneHandles.DirectionHandle(rightId, rightPoint, -rightVector);
                }
            }
            if (EditorGUI.EndChangeCheck())
            {
                Undo.RecordObject(target, "Modified " + generator.NodeTypeName);
                generator.definition.height   = topPoint.y - bottomPoint.y;
                generator.definition.length   = Mathf.Max(0, frontPoint.z - backPoint.z);
                generator.definition.diameter = leftPoint.x - rightPoint.x;
                generator.OnValidate();
                // TODO: handle sizing in some directions (needs to modify transformation?)
            }
        }