Added collission detection

Signed-off-by: Hans Kokx <hans.d.kokx@gmail.com>

raycaster.c

@@ -792,20 +792,71 @@ void display()
     playerDeltaY = sin(playerAngle) * 5.0f;
   }
 
+  // We need to check if we're going to bump into a wall
+  // and prevent that from happening.
+
+  int movementRestriction = 5;
+
+  int xOffset = 0;
+  if (playerDeltaX < 0)
+  {
+    xOffset = -movementRestriction;
+  }
+  else
+  {
+    xOffset = movementRestriction;
+  }
+
+  int yOffset = 0;
+  if (playerDeltaY < 0)
+  {
+    yOffset = -movementRestriction;
+  }
+  else
+  {
+    yOffset = movementRestriction;
+  }
+
+  // Convert pixel positions to map grid coordinates dynamically using mapSize
+  int iPlayerX = (int)playerX / mapSize;
+  int iPlayerY = (int)playerY / mapSize;
+
+  int iPlayerX_add_xOffset = (int)(playerX + xOffset) / mapSize;
+  int iPlayerY_add_yOffset = (int)(playerY + yOffset) / mapSize;
+
+  int iPlayerX_sub_xOffset = (int)(playerX - xOffset) / mapSize;
+  int iPlayerY_sub_yOffset = (int)(playerY - yOffset) / mapSize;
+
   // ? Move forward
   if (Keys.w == 1)
   {
     // We change the X and Y values based on our delta, which is calculated
     // during our rotation.
-    playerX += playerDeltaX * movementMultiplier;
-    playerY += playerDeltaY * movementMultiplier;
+    if (map[iPlayerY * mapX + iPlayerX_add_xOffset] == 0)
+    {
+
+      playerX += playerDeltaX * movementMultiplier;
+    }
+
+    if (map[iPlayerY_add_yOffset * mapX + iPlayerX] == 0)
+    {
+
+      playerY += playerDeltaY * movementMultiplier;
+    }
   }
 
   // ? Move backwards
   if (Keys.s == 1)
   {
-    playerX -= playerDeltaX * movementMultiplier;
-    playerY -= playerDeltaY * movementMultiplier;
+    if (map[iPlayerY * mapX + iPlayerX_sub_xOffset] == 0)
+    {
+      playerX -= playerDeltaX * movementMultiplier;
+    }
+
+    if (map[iPlayerY_sub_yOffset * mapX + iPlayerX] == 0)
+    {
+      playerY -= playerDeltaY * movementMultiplier;
+    }
   }
   glutPostRedisplay();