Changeset 9802

Timestamp:

Nov 21, 2013, 10:11:27 PM (11 years ago)

Author:

jo

Message:

Making the Tetris collision detection more robust, by decoupling stone-stone collisions and stone-brick collisions.

Location:

code/trunk/src/modules/tetris

Files:

• Tetris.cc (modified) (5 diffs)
• Tetris.h (modified) (1 diff)

code/trunk/src/modules/tetris/Tetris.cc

@@ -183 +183 @@
 
 
-
-    bool Tetris::isValidStonePosition(TetrisStone* stone, const Vector3& position)
+    /**
+     * @brief Returns true, if NO collision was detected.
+     * Else returns false and the active brick is repositioned as side-effect.
+     */
+    bool Tetris::checkStoneStoneCollision(TetrisStone* stone, const Vector3& position)
     {
         assert(stone);
@@ -193 +196 @@
             //Vector3 currentStonePosition = rotateVector((*it)->getPosition(), this->activeBrick_->getRotationCount());
             const Vector3& currentStonePosition = (*it)->getPosition(); //!< Saves the position of the currentStone
-            //!< Saves the position of the currentStone
 
             //filter out cases where the falling stone is already below a steady stone
@@ -208 +210 @@
         }
 
-        // after we checked for collision with all stones, we also check for collision with the bottom
+        return true;
+    }
+    
+    /**
+     * @brief Returns true, if NO collision was detected.
+     * Else returns false and the active brick is repositioned as side-effect.
+     */
+    bool Tetris::checkStoneBottomCollision(TetrisStone* stone, const Vector3& position)
+    {
+        assert(stone);
         if(position.y < this->center_->getStoneSize()/2.0f) //!< If the stone has reached the bottom of the level
         {
@@ -220 +231 @@
             return false;
         }
-
         return true;
     }
+    
     /**
      * @brief This function determines wether a brick touches another brick or the ground.
@@ -238 +249 @@
             TetrisStone* stone = brick->getStone(i);
             const Vector3& stonePosition = rotateVector(stone->getPosition(), brick->getRotationCount());
-            if(! this->isValidStonePosition(stone, brickPosition + stonePosition) )
-            {
-                // recurse because all stones have to checked again after the brick was re-positioned
+            if(! this->checkStoneStoneCollision(stone, brickPosition + stonePosition) )
+            {
                 return false;
             }
         }
+        // check all stones in the brick
+        for (unsigned int i = 0; i < brick->getNumberOfStones(); i++ )
+        {
+            TetrisStone* stone = brick->getStone(i);
+            const Vector3& stonePosition = rotateVector(stone->getPosition(), brick->getRotationCount());
+            if(! this->checkStoneBottomCollision(stone, brickPosition + stonePosition) )
+            {
+                return false;
+            }
+        }
+        
         return true;
     }

code/trunk/src/modules/tetris/Tetris.h

@@ -83 +83 @@
             void createBrick(void);
             void cleanup(void); //!< Cleans up the Gametype by destroying the ball and the bats.
-            bool isValidStonePosition(TetrisStone* stone, const Vector3& position);
+            bool checkStoneStoneCollision(TetrisStone* stone, const Vector3& position);
+            bool checkStoneBottomCollision(TetrisStone* stone, const Vector3& position);
             bool isValidBrickPosition(TetrisBrick* brick);
             void findFullRows(void);