/************************************************************************************************************************/

        /// <summary>
        /// Draws controls for <see cref="AnimancerState.IsPlaying"/>, <see cref="AnimancerState.Speed"/>, and
        /// <see cref="AnimancerState.Weight"/>.
        /// </summary>
        protected void DoPlayingDetailsGUI()
        {
            var labelWidth = EditorGUIUtility.labelWidth;

            var area = AnimancerEditorUtilities.GetRect(true);

            var right = area.xMax;

            // Is Playing.
            var label = AnimancerEditorUtilities.BeginTightLabel("Is Playing");

            area.width      = EditorGUIUtility.labelWidth + 16;
            State.IsPlaying = EditorGUI.Toggle(area, label, State.IsPlaying);
            AnimancerEditorUtilities.EndTightLabel();

            area.x   += area.width;
            area.xMax = right;

            float speedWidth, weightWidth;
            Rect  speedRect, weightRect;

            AnimancerEditorUtilities.SplitHorizontally(area, "Speed", "Weight", out speedWidth, out weightWidth, out speedRect, out weightRect);

            var indentLevel = EditorGUI.indentLevel;

            EditorGUI.indentLevel = 0;

            // Speed.
            EditorGUIUtility.labelWidth = speedWidth;
            EditorGUI.BeginChangeCheck();
            var speed = EditorGUI.FloatField(speedRect, "Speed", State.Speed);

            if (EditorGUI.EndChangeCheck())
            {
                State.Speed = speed;
            }

            // Weight.
            EditorGUIUtility.labelWidth = weightWidth;
            EditorGUI.BeginChangeCheck();
            var weight = EditorGUI.FloatField(weightRect, "Weight", State.Weight);

            if (EditorGUI.EndChangeCheck())
            {
                State.Weight = weight;
            }

            EditorGUI.indentLevel       = indentLevel;
            EditorGUIUtility.labelWidth = labelWidth;
        }