Unity_Utils/Editor/PropertyDrawers/RangedFloatDrawer.cs

using UnityEditor;
using UnityEngine;
using Util.CustomTypes;

namespace Editor.PropertyDrawer
{
    [CustomPropertyDrawer(typeof(RangedFloat), true)]
    public class RangedFloatDrawer : UnityEditor.PropertyDrawer
    {
        public override void OnGUI(Rect position, SerializedProperty property, GUIContent label)
        {
            label = EditorGUI.BeginProperty(position, label, property);
            position = EditorGUI.PrefixLabel(position, label);

            var minProp = property.FindPropertyRelative("minValue");
            var maxProp = property.FindPropertyRelative("maxValue");

            var minValue = minProp.floatValue;
            var maxValue = maxProp.floatValue;

            float rangeMin = 0;
            float rangeMax = 1;

            var ranges = (MinMaxRangeAttribute[]) fieldInfo.GetCustomAttributes(typeof(MinMaxRangeAttribute), true);

            if (ranges.Length > 0)
            {
                rangeMin = ranges[0].Min;
                rangeMax = ranges[0].Max;
            }

            const float rangeBoundsLabelWidth = 40f;

            var rangeBoundsLabel1Rect = new Rect(position) {width = rangeBoundsLabelWidth};
            GUI.Label(rangeBoundsLabel1Rect, new GUIContent(minValue.ToString("F2")));
            position.xMin += rangeBoundsLabelWidth;

            var rangeBoundsLabel2Rect = new Rect(position);
            rangeBoundsLabel2Rect.xMin = rangeBoundsLabel2Rect.xMax - rangeBoundsLabelWidth + 5;
            GUI.Label(rangeBoundsLabel2Rect, new GUIContent(maxValue.ToString("F2")));
            position.xMax -= rangeBoundsLabelWidth;

            EditorGUI.BeginChangeCheck();
            EditorGUI.MinMaxSlider(position, ref minValue, ref maxValue, rangeMin, rangeMax);
            if (EditorGUI.EndChangeCheck())
            {
                minProp.floatValue = minValue;
                maxProp.floatValue = maxValue;
            }

            EditorGUI.EndProperty();
        }
    }
}