From 1317c59e94ffe942db5a3e7b6d6e2367f05346bb Mon Sep 17 00:00:00 2001
From: Jens Pitkanen <jens@neon.moe>
Date: Sat, 8 Aug 2020 03:57:37 +0300
Subject: [PATCH] Optimize terminal text display

---
 Assets/Prefabs/UI/TerminalRoot.prefab |  4 +++-
 Assets/Scripts/Interface/Terminal.cs  | 25 +++++++++++++++++++++----
 2 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/Assets/Prefabs/UI/TerminalRoot.prefab b/Assets/Prefabs/UI/TerminalRoot.prefab
index f25013f..fad5929 100644
--- a/Assets/Prefabs/UI/TerminalRoot.prefab
+++ b/Assets/Prefabs/UI/TerminalRoot.prefab
@@ -53,6 +53,8 @@ MonoBehaviour:
   InputField: {fileID: 7286298882252502165}
   TextField: {fileID: 4807139487522286296}
   Player: {fileID: 0}
+  LinesVisibleAtOnce: 32
+  TerminalScrollbar: {fileID: 4580324269108703239}
 --- !u!1 &170678579363757794
 GameObject:
   m_ObjectHideFlags: 0
@@ -398,7 +400,7 @@ MonoBehaviour:
   m_TargetGraphic: {fileID: 2282722458285268294}
   m_HandleRect: {fileID: 4556893897637480247}
   m_Direction: 2
-  m_Value: 0
+  m_Value: 1
   m_Size: 1
   m_NumberOfSteps: 0
   m_OnValueChanged:
diff --git a/Assets/Scripts/Interface/Terminal.cs b/Assets/Scripts/Interface/Terminal.cs
index c7d0e10..1e5d5ea 100644
--- a/Assets/Scripts/Interface/Terminal.cs
+++ b/Assets/Scripts/Interface/Terminal.cs
@@ -1,9 +1,10 @@
 using System.Collections.Generic;
 using System;
-using System.Collections;
+using System.Text;
 using UnityEngine;
 using UnityEngine.InputSystem;
 using UnityEngine.EventSystems;
+using UnityEngine.UI;
 using NeonTea.Quakeball.Players;
 using TMPro;
 
@@ -14,6 +15,9 @@ namespace NeonTea.Quakeball.Interface {
         public TMP_InputField InputField;
         public TMP_Text TextField;
         public LocalPlayer Player;
+        [Tooltip("Used to optimize the amount of text rendered. 0 for no optimization.")]
+        public float LinesVisibleAtOnce;
+        public Scrollbar TerminalScrollbar;
 
         private InputAction ToggleTerminalAction;
         private InputAction SubmitTerminal;
@@ -24,7 +28,6 @@ namespace NeonTea.Quakeball.Interface {
         private Dictionary<string, string> Helps = new Dictionary<string, string>();
 
         private List<string> Messages = new List<string>();
-        private string Text = "";
         private List<string> PreviousRuns = new List<string>();
         private int CurrentScroll = -1;
         private bool JustScrolled = false;
@@ -101,8 +104,22 @@ namespace NeonTea.Quakeball.Interface {
                 InputField.readOnly = false;
             }
             if (IsOpen) {
-                Text = String.Join("\n", Messages);
-                TextField.text = Text;
+                if (LinesVisibleAtOnce == 0) {
+                    TextField.text = String.Join("\n", Messages);
+                } else {
+                    float VisibleLinesCenterIndex = (1 - TerminalScrollbar.value) * Messages.Count;
+                    int StartIndex = Mathf.Max(0, (int)(VisibleLinesCenterIndex - LinesVisibleAtOnce / 2));
+                    int EndIndex = Mathf.Min(Messages.Count - 1, (int)(VisibleLinesCenterIndex + LinesVisibleAtOnce / 2));
+                    StringBuilder OptimizedText = new StringBuilder();
+                    for (int i = 0; i < Messages.Count; i++) {
+                        if (i < StartIndex || i > EndIndex) {
+                            OptimizedText.AppendLine();
+                        } else {
+                            OptimizedText.AppendLine(Messages[i]);
+                        }
+                    }
+                    TextField.text = OptimizedText.ToString();
+                }
             }
         }