From 671c8d6f7c9a5e1e0c43ab600e0cf6fac7ee44b7 Mon Sep 17 00:00:00 2001
From: Kaj Forney <kaj.forney@gmail.com>
Date: Thu, 21 Oct 2021 11:06:46 -0600
Subject: [PATCH] Verify that a player move wouldn't collide before doing it.
 TODO: check rotations as well.

---
 Assets/Scripts/tetrominoUserControl.cs | 46 ++++++++++++++++++++++----
 1 file changed, 40 insertions(+), 6 deletions(-)

diff --git a/Assets/Scripts/tetrominoUserControl.cs b/Assets/Scripts/tetrominoUserControl.cs
index bb9dcd1..edc5549 100644
--- a/Assets/Scripts/tetrominoUserControl.cs
+++ b/Assets/Scripts/tetrominoUserControl.cs
@@ -17,20 +17,29 @@ public class tetrominoUserControl : MonoBehaviour
     {
         if (Input.GetButtonDown("tetrisMoveLeft") && activeTetromino != null)
         {
-            activeTetromino.gameObject.transform.position += Vector3.left * 1.0f;
-            GetComponent<AudioSource>().Play();
+            if (!checkMoveCollisions(Vector2.left))
+            {
+                activeTetromino.gameObject.transform.position += Vector3.left * 1.0f;
+                GetComponent<AudioSource>().Play();
+            }
         }
         
         if (Input.GetButtonDown("tetrisMoveRight") && activeTetromino != null)
         {
-            activeTetromino.gameObject.transform.position += Vector3.right * 1.0f;
-            GetComponent<AudioSource>().Play();
+            if (!checkMoveCollisions(Vector2.right))
+            {
+                activeTetromino.gameObject.transform.position += Vector3.right * 1.0f;
+                GetComponent<AudioSource>().Play();
+            }
         }
 
         if (Input.GetButtonDown("tetrisDrop") && activeTetromino != null)
         {
-            activeTetromino.gameObject.transform.position += Vector3.down * 1.0f;
-            GetComponent<AudioSource>().Play();
+            if (!checkMoveCollisions(Vector2.down))
+            {
+                activeTetromino.gameObject.transform.position += Vector3.down * 1.0f;
+                GetComponent<AudioSource>().Play();
+            }
         }
 
         if (Input.GetButtonDown("tetrisRotateLeft") && activeTetromino != null)
@@ -55,4 +64,29 @@ public class tetrominoUserControl : MonoBehaviour
     {
         activeTetromino = null;
     }
+
+    public bool checkMoveCollisions(Vector2 direction)
+    {
+        bool wouldCollide = false;
+        
+        foreach (Transform child in activeTetromino.transform)
+        {
+            RaycastHit2D collision = Physics2D.Raycast(child.position, direction, 1.0f);
+            // Debug.DrawRay(pieceToCheck.position,Vector3.down,Color.red,1000.0f);
+            if (collision.collider != null && collision.collider.transform.parent != child.parent)
+            {
+                wouldCollide = true;
+            }
+
+        }
+
+        if (wouldCollide == true)
+        {
+            return true;
+        }
+        else
+        {
+            return false;
+        }
+    }
 }