Changeset 8661 for code/branches/presentation/src/modules/tetris

Timestamp:

May 29, 2011, 5:01:53 PM (13 years ago)

Author:

landauf

Message:

fixed two possible causes which stacked multiple tetris stones at the same position (happens if a stone moves so fast that it "tunnels" the topmost stone. before the collisions were checked from lower to upper, now its the other way round, which fixes the issue)

File:

• code/branches/presentation/src/modules/tetris/Tetris.cc (modified) (2 diffs)

code/branches/presentation/src/modules/tetris/Tetris.cc

@@ -127 +127 @@
         assert(stone);
 
-        if(position.y < this->center_->getStoneSize()/2.0f) //!< If the stone has reached the bottom of the level
-        {
-            stone->setPosition(Vector3(stone->getPosition().x, this->center_->getStoneSize()/2.0f, stone->getPosition().z));
-            return false;
-        }
-
-        for(std::vector<TetrisStone*>::const_iterator it = this->stones_.begin(); it != this->stones_.end(); ++it)
+        // we use a reverse iterator because we have to check for collisions with the topmost stones first
+        for(std::vector<TetrisStone*>::const_reverse_iterator it = this->stones_.rbegin(); it != this->stones_.rend(); ++it)
         {
             if(stone == *it)
@@ -145 +140 @@
                 return false;
             }// This case applies if the stones overlap partially vertically
+        }
+
+        // after we checked for collision with all stones, we also check for collision with the bottom
+        if(position.y < this->center_->getStoneSize()/2.0f) //!< If the stone has reached the bottom of the level
+        {
+            stone->setPosition(Vector3(stone->getPosition().x, this->center_->getStoneSize()/2.0f, stone->getPosition().z));
+            return false;
         }