Add inventory system

Ajout d'un "backend" pour un systeme d'inventaire
reste a faire le cablage et a afficher une UI a l'ecran
pour avoir un retour de l'etat de l'inventaire
Le remplissage de l'inventaire du joueur est censé se faire
via un gameobject GameManager qui n'existe pas encore, il reste donc
vide jusqu'a nouvel ordre.
Le code n'a pas été testé donc je balance un code de schrodinger B)

FreeCam/Assets/BlockSpawner.cs

-using System.Collections;
-using System.Collections.Generic;
-using UnityEngine;
-using UnityEngine.InputSystem;
-
-public class BlockSpawner : MonoBehaviour
-{
-    [SerializeField]
-    private GameObject _blockToPlace;
-    public GameObject BlockToPlace
-    {
-        get
-        {
-            return _blockToPlace;
-        }
-        set
-        {
-            DisablePreviewMode();
-            _blockToPlace = value;
-        }
-    }
-
-    public float spawnDistance = 3f;
-
-    private GameObject _blockInstance;
-
-    private bool _isPreview = false;
-
-    public void OnPlaceBlock()
-    {
-        if (!_isPreview) return;
-        _blockInstance.transform.SetParent(null);
-        _blockInstance = null;
-        DisablePreviewMode();
-    }
-
-    public void OnTogglePreviewMode(InputValue value)
-    {
-        float valueAsFloat = value.Get<float>();
-
-        if (valueAsFloat == 1f) EnablePreviewMode();
-        else DisablePreviewMode();
-    }
-
-    private void EnablePreviewMode()
-    {
-        if (_blockToPlace == null) return;
-
-        Vector3 spawnPos = Vector3.forward * spawnDistance;
-        _blockInstance = Instantiate(_blockToPlace, spawnPos, Quaternion.identity);
-        _blockInstance.transform.SetParent(this.transform, false);
-        _isPreview = true;
-    }
-
-    private void DisablePreviewMode()
-    {
-        if (_blockInstance != null) Destroy(_blockInstance);
-        _isPreview = false;
-    }
-}

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FreeCam/Assets/Scenes/SampleScene.unity

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FreeCam/Assets/Scripts/BlockSpawner.cs

+using System.Collections.Generic;
+using UnityEngine;
+using UnityEngine.InputSystem;
+
+public class BlockSpawner : MonoBehaviour
+{
+    public Inventory inventory;
+
+    public float spawnDistance = 3f;
+    
+    #pragma warning disable 0649
+    [SerializeField] private UI_Inventory uiInventory;
+    #pragma warning restore 0649
+    private GameObject _blockInstance;
+
+    private bool _isPreview;
+
+    public void Awake()
+    {
+        _isPreview = false;
+
+        inventory = new Inventory();
+        uiInventory.SetInventory(inventory);
+    }
+
+    public void OnPlaceBlock ()
+    {
+        if (!_isPreview) return;
+        // todo remove in inventory
+        _blockInstance.transform.SetParent(null);
+        _blockInstance = null;
+        DisablePreviewMode();
+    }
+
+    public void OnTogglePreviewMode(InputValue value)
+    {
+        float valueAsFloat = value.Get<float>();
+
+        if (valueAsFloat == 1f) EnablePreviewMode();
+        else DisablePreviewMode();
+    }
+
+    public void OnScroll(InputValue value)
+    {
+        DisablePreviewMode();
+
+        float valueAsFloat = value.Get<float>();
+        if (valueAsFloat > 0) inventory.SelectPreviousItem();
+        if (valueAsFloat < 0) inventory.SelectNextItem();
+    }
+
+    public void EnablePreviewMode()
+    {
+        Item selectedItem = inventory.GetSelectedItem();
+
+        if (selectedItem == null) return;
+
+        Vector3 spawnPos = Vector3.forward * spawnDistance;
+        _blockInstance = Instantiate(selectedItem.Prefab, spawnPos, Quaternion.identity);
+        _blockInstance.transform.SetParent(this.transform, false);
+        _isPreview = true;
+    }
+
+    public void DisablePreviewMode()
+    {
+        if (_blockInstance != null) Destroy(_blockInstance);
+        _isPreview = false;
+    }
+}

FreeCam/Assets/Scripts/Inventory.cs

+using System;
+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+
+public class Inventory
+{
+    public event EventHandler OnItemListChanged;
+
+    private List<Item> itemList;
+    private Item selectedItem;
+
+    public Inventory()
+    {
+        itemList = new List<Item>();
+        selectedItem = null;
+    }
+
+    public void AddItem(Item item)
+    {
+        bool itemAlreadyInInventory = false;
+
+        foreach (Item itemSlot in itemList)
+        {
+            if (itemSlot.Prefab == item.Prefab)
+            {
+                itemSlot.Increase(item.Amount);
+                itemAlreadyInInventory = true;
+            }
+        }
+
+        if (!itemAlreadyInInventory) itemList.Add(item);
+        if (selectedItem == null) selectedItem = item;
+
+        OnItemListChanged?.Invoke(this, EventArgs.Empty);
+    }
+
+    public void RemoveItem(Item item)
+    {
+        Item itemInInventory = null;
+
+        foreach (Item inventoryItem in itemList)
+        {
+            if (inventoryItem.Prefab == item.Prefab)
+            {
+                inventoryItem.Decrease(item.Amount);
+                itemInInventory = inventoryItem;
+            }
+        }
+
+        if (itemInInventory != null && itemInInventory.IsEmpty())
+        {
+            if (itemInInventory == selectedItem)
+                selectedItem = ItemAfter(selectedItem) ?? ItemBefore(selectedItem);
+
+            itemList.Remove(itemInInventory);
+        }
+
+        OnItemListChanged?.Invoke(this, EventArgs.Empty);
+    }
+
+    public List<Item> GetItemList()
+    {
+        return itemList;
+    }
+
+    public Item GetSelectedItem()
+    {
+        return selectedItem;
+    }
+
+    public Item ItemBefore(Item item)
+    {
+        int idx = itemList.IndexOf(item);
+
+        if (idx == -1 || idx == 0) return null;
+        return itemList[idx - 1];
+    }
+
+    public Item ItemAfter(Item item)
+    {
+        int idx = itemList.IndexOf(item);
+
+        if (idx == -1 || idx == itemList.Count) return null;
+        return itemList[idx + 1];
+    }
+
+    public void SelectPreviousItem()
+    {
+        Item newSelected = ItemBefore(selectedItem);
+        if (newSelected == null) return;
+
+        OnItemListChanged?.Invoke(this, EventArgs.Empty);
+    }
+
+    public void SelectNextItem()
+    {
+        Item newSelected = ItemAfter(selectedItem);
+        if (newSelected == null) return;
+
+        OnItemListChanged?.Invoke(this, EventArgs.Empty);
+    }
+}

FreeCam/Assets/Scripts/Inventory.cs.meta

+fileFormatVersion: 2
+guid: ec3d79877253fcb41abb245d3f2e07f9
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
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+  userData: 
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+  assetBundleVariant: 

FreeCam/Assets/Scripts/Item.cs

+using System;
+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+
+[Serializable]
+public class Item
+{
+    public GameObject Prefab { get; private set; }
+    public int Amount { get; private set; }
+    private Sprite sprite;
+
+    public Item(GameObject _prefab, int _amount)
+    {
+        Prefab = _prefab;
+        Amount = _amount;
+        InitiateSprite();
+    }
+
+    public Sprite GetSprite()
+    {
+        return sprite;
+    }
+
+    private void InitiateSprite()
+    {
+        Texture2D texture = UnityEditor.AssetPreview.GetMiniThumbnail(Prefab);
+        Rect rect = new Rect(0, 0, texture.width, texture.height);
+        Vector2 pivot = new Vector2(0.5f, 0.5f);
+        sprite = Sprite.Create(texture, rect, pivot);
+    }
+
+    public void Increase(int _amount)
+    {
+        Amount += _amount;
+    }
+
+    public void Decrease(int _amount)
+    {
+        Amount -= _amount;
+    }
+
+    public bool IsEmpty()
+    {
+        return Amount <= 0;
+    }
+}

FreeCam/Assets/Scripts/Item.cs.meta

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+guid: d955f3cb1be5bcf45a17f8bf49133023
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+  externalObjects: {}
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+  userData: 
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+  assetBundleVariant: 

FreeCam/Assets/Scripts/UI_Inventory.cs

+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+
+public class UI_Inventory : MonoBehaviour
+{
+
+    private Inventory inventory;
+
+    private void Awake()
+    {
+        
+    }
+
+    public void SetInventory(Inventory _inventory)
+    {
+        inventory = _inventory;
+
+        inventory.OnItemListChanged += Inventory_OnItemListChanged;
+
+        RefreshInventoryItems();
+    }
+
+    private void Inventory_OnItemListChanged(object sender, System.EventArgs e)
+    {
+        RefreshInventoryItems();
+    }
+
+    private void RefreshInventoryItems()
+    {
+        // TODO refresh UI
+    }
+
+
+}

FreeCam/Assets/Scripts/UI_Inventory.cs.meta

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