Improve FPS display formatting

Author: adamgraham

Prefabs/FPSDisplay.prefab

@@ -11,7 +11,6 @@ GameObject:
   - component: {fileID: 2560411229158870742}
   - component: {fileID: 2560411229158870743}
   - component: {fileID: 2560411229158870744}
-  - component: {fileID: 2560411229158870745}
   - component: {fileID: 7135560934737295104}
   m_Layer: 5
   m_Name: FPSDisplay
@@ -83,23 +82,6 @@ MonoBehaviour:
   m_FallbackScreenDPI: 96
   m_DefaultSpriteDPI: 96
   m_DynamicPixelsPerUnit: 1
---- !u!114 &2560411229158870745
-MonoBehaviour:
-  m_ObjectHideFlags: 0
-  m_CorrespondingSourceObject: {fileID: 0}
-  m_PrefabInstance: {fileID: 0}
-  m_PrefabAsset: {fileID: 0}
-  m_GameObject: {fileID: 2560411229158870746}
-  m_Enabled: 1
-  m_EditorHideFlags: 0
-  m_Script: {fileID: 11500000, guid: dc42784cf147c0c48a680349fa168899, type: 3}
-  m_Name: 
-  m_EditorClassIdentifier: 
-  m_IgnoreReversedGraphics: 1
-  m_BlockingObjects: 0
-  m_BlockingMask:
-    serializedVersion: 2
-    m_Bits: 4294967295
 --- !u!114 &7135560934737295104
 MonoBehaviour:
   m_ObjectHideFlags: 0
@@ -114,6 +96,7 @@ MonoBehaviour:
   m_EditorClassIdentifier: 
   displayText: {fileID: 2560411230916416746}
   refreshRate: 1
+  _decimals: 0
 --- !u!1 &2560411230916416749
 GameObject:
   m_ObjectHideFlags: 0
@@ -174,8 +157,8 @@ MonoBehaviour:
   m_EditorClassIdentifier: 
   m_Material: {fileID: 0}
   m_Color: {r: 1, g: 1, b: 1, a: 1}
-  m_RaycastTarget: 1
-  m_Maskable: 1
+  m_RaycastTarget: 0
+  m_Maskable: 0
   m_OnCullStateChanged:
     m_PersistentCalls:
       m_Calls: []
@@ -192,7 +175,7 @@ MonoBehaviour:
     m_HorizontalOverflow: 1
     m_VerticalOverflow: 1
     m_LineSpacing: 1
-  m_Text: 
+  m_Text: 0
 --- !u!114 &2560411230916416747
 MonoBehaviour:
   m_ObjectHideFlags: 0

Runtime/FPSDisplay.cs

@@ -1,4 +1,5 @@
-using UnityEngine;
+using System.Text;
+using UnityEngine;
 using UnityEngine.UI;
 
 namespace Zigurous.Debug
@@ -16,30 +17,83 @@ public class FPSDisplay : MonoBehaviour
         public Text displayText;
 
         /// <summary>
-        /// How often per second the framerate display updates.
+        /// The text format of the framerate display.
         /// </summary>
-        [Tooltip("How often per second the framerate display updates.")]
+        public string displayFormat { get; protected set; }
+
+        /// <summary>
+        /// The amount of seconds between display updates.
+        /// </summary>
+        [Tooltip("The amount of seconds between display updates.")]
         public float refreshRate = 1.0f;
 
+        /// <summary>
+        /// The number of decimal digits to display.
+        /// </summary>
+        [Tooltip("The number of decimal digits to display.")]
+        [SerializeField]
+        private int _decimals = 0;
+
+        /// <summary>
+        /// The number of decimal digits to display.
+        /// </summary>
+        public int decimals
+        {
+            get => _decimals;
+            set
+            {
+                _decimals = value;
+                SetDisplayFormat(value);
+            }
+        }
+
         /// <summary>
         /// The time of the next framerate update.
         /// </summary>
         protected float _nextUpdate;
 
+        private void OnValidate()
+        {
+            SetDisplayFormat(this.decimals);
+        }
+
+        private void Awake()
+        {
+            SetDisplayFormat(this.decimals);
+        }
+
         private void Update()
         {
             if (Time.unscaledTime > _nextUpdate)
             {
-                int fps = (int)(1.0f / Time.unscaledDeltaTime);
-                UpdateDisplay(fps);
                 _nextUpdate = Time.unscaledTime + this.refreshRate;
+
+                float fps = 1.0f / Time.unscaledDeltaTime;
+                UpdateDisplay(fps);
             }
         }
 
-        protected virtual void UpdateDisplay(int fps)
+        private void SetDisplayFormat(int decimals)
+        {
+            int length = 1 + decimals;
+            if (decimals > 0) length++;
+
+            StringBuilder stringBuilder = new StringBuilder(length);
+            stringBuilder.Append('0');
+
+            if (decimals > 0)
+            {
+                stringBuilder.Append('.');
+                stringBuilder.Insert(2, "0", decimals);
+            }
+
+            this.displayFormat = stringBuilder.ToString();
+        }
+
+        protected virtual void UpdateDisplay(float fps)
         {
             if (this.displayText != null) {
-                this.displayText.text = fps.ToString();
+                this.displayText.text = fps.ToString(this.displayFormat);
             }
         }