/// <summary>
/// Detects and resolves all collisions between the player and his neighboring
/// tiles. When a collision is detected, the player is pushed away along one
/// axis to prevent overlapping. There is some special logic for the Y axis to
/// handle platforms which behave differently depending on direction of movement.
/// </summary>
private void HandleCollisions()
{
// Get the player's bounding rectangle and find neighboring tiles.
Rectangle bounds = BoundingRectangle;
int leftTile = (int)Math.Floor((float)bounds.Left / Tile.Width);
int rightTile = (int)Math.Ceiling(((float)bounds.Right / Tile.Width)) - 1;
int topTile = (int)Math.Floor((float)bounds.Top / Tile.Height);
int bottomTile = (int)Math.Ceiling(((float)bounds.Bottom / Tile.Height)) - 1;
// Reset flag to search for ground collision.
isOnGround = false;
// For each potentially colliding tile,
for (int y = topTile; y <= bottomTile; ++y)
{
for (int x = leftTile; x <= rightTile; ++x)
{
// If this tile is collidable,
TileCollision collision = Level.GetCollision(x, y);
if (collision != TileCollision.Passable)
{
// Determine collision depth (with direction) and magnitude.
Rectangle tileBounds = Level.GetBounds(x, y);
Vector2 depth = RectangleExtensions.GetIntersectionDepth(bounds, tileBounds);
if (depth != Vector2.Zero)
{
float absDepthX = Math.Abs(depth.X);
float absDepthY = Math.Abs(depth.Y);
// Resolve the collision along the shallow axis.
if (absDepthY < absDepthX || collision == TileCollision.Platform)
{
// If we crossed the top of a tile, we are on the ground.
if (previousBottom <= tileBounds.Top)
{
isOnGround = true;
}
// Ignore platforms, unless we are on the ground.
if (collision == TileCollision.Impassable || IsOnGround)
{
// Resolve the collision along the Y axis.
Position = new Vector2(Position.X, Position.Y + depth.Y);
// Perform further collisions with the new bounds.
bounds = BoundingRectangle;
}
}
else if (collision == TileCollision.Impassable) // Ignore platforms.
{
// Resolve the collision along the X axis.
Position = new Vector2(Position.X + depth.X, Position.Y);
// Perform further collisions with the new bounds.
bounds = BoundingRectangle;
}
}
}
}
}
// Save the new bounds bottom.
previousBottom = bounds.Bottom;
}
/// <summary>
/// Detects and resolves all collisions between the player and his neighboring
/// tiles. When a collision is detected, the player is pushed away along one
/// axis to prevent overlapping. There is some special logic for the Y axis to
/// handle platforms which behave differently depending on direction of movement.
/// </summary>
private void HandleCollisions()
{
// Get the player's bounding rectangle and find neighboring tiles.
Rectangle bounds = BoundingRectangle;
int[] ltArray = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1 };
int[] rtArray = { 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 };
int[] ttArray = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 };
int[] btArray = { 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2 };
int leftTile = 0;
int rightTile = 0;
int topTile = 0;
int bottomTile = 0;
//Vector2 drawPosn = GetDrawPosn();
Vector2 collPosn = GetCollPosn();
//if (drawPosn.X < 0)
//{
// leftTile = drawPosn.X < -4 ? -1 : 0;
//}
//else
//{
int idxX = (int)collPosn.X;
int quoX = (int)(idxX / Tile.Size.X);
int remX = (int)(idxX % Tile.Size.X);
if (remX < 0)
{
remX = 0;
}
int idxLeftTile = ltArray[remX];
int idxRightTile = rtArray[remX];
leftTile = idxLeftTile + quoX;
rightTile = idxRightTile + quoX;
//}
//if (drawPosn.Y < 0)
//{
// topTile = drawPosn.Y < -12 ? -1 : 0;
//}
//else
//{
int idxY = (int)collPosn.Y;
int quoY = (int)(idxY / Tile.Size.Y);
int remY = (int)(idxY % Tile.Size.Y);
// this won't crash at least but will go off the sides
if (remY < 0)
{
remY = 0;
}
int idxTopTile = ttArray[remY];
int idxBottomTile = btArray[remY];
topTile = idxTopTile + quoY;
bottomTile = idxBottomTile + quoY;
//}
int leftTile2 = (int)Math.Floor((float)bounds.Left / Tile.Width);
int rightTile2 = (int)Math.Ceiling(((float)bounds.Right / Tile.Width)) - 1;
int topTile2 = (int)Math.Floor((float)bounds.Top / Tile.Height);
int bottomTile2 = (int)Math.Ceiling(((float)bounds.Bottom / Tile.Height)) - 1;
if (leftTile != leftTile2 || rightTile != rightTile2 || topTile != topTile2 || bottomTile != bottomTile2)
{
//String msg = String.Format("(X,Y)=({0},{1}), L:{2} R:{3} T:{4} B:{5}", (int)position.X, (int)position.Y, leftTile, rightTile, topTile, bottomTile);
//String msg = String.Format("BoundL:{0} BoundT:{1} BoundW:{2} BoundH:{3}", bounds.Left, bounds.Top, bounds.Width, bounds.Height);
//Logger.Info(msg);
}
if (shouldLog)
{
//String msg = String.Format("(X,Y)=({0},{1}), L:{2} R:{3} T:{4} B:{5}", (int) position.X, (int) position.Y, leftTile, rightTile, topTile, bottomTile);
//String msg = String.Format("BoundL:{0} BoundT:{1} BoundW:{2} BoundH:{3}", bounds.Left, bounds.Top, bounds.Width, bounds.Height);
//Logger.Info(msg);
}
// Reset flag to search for ground collision.
isOnGround = false;
// For each potentially colliding tile,
for (int y = topTile; y <= bottomTile; ++y)
{
for (int x = leftTile; x <= rightTile; ++x)
{
// If this tile is collidable,
TileCollision collision = Level.GetCollision(x, y);
if (collision != TileCollision.Passable)
{
// Determine collision depth (with direction) and magnitude.
Rectangle tileBounds = Level.GetBounds(x, y);
Vector2 depth = RectangleExtensions.GetIntersectionDepth(bounds, tileBounds);
if (depth != Vector2.Zero)
{
float absDepthX = Math.Abs(depth.X);
float absDepthY = Math.Abs(depth.Y);
// Resolve the collision along the shallow axis.
if (absDepthY < absDepthX || collision == TileCollision.Platform)
{
// If we crossed the top of a tile, we are on the ground.
if (previousBottom <= tileBounds.Top)
{
isOnGround = true;
}
// Ignore platforms, unless we are on the ground.
if (collision == TileCollision.Impassable || IsOnGround)
{
// Resolve the collision along the Y axis.
Position = new Vector2(Position.X, Position.Y + depth.Y);
// Perform further collisions with the new bounds.
bounds = BoundingRectangle;
}
}
else if (collision == TileCollision.Impassable) // Ignore platforms.
{
// Resolve the collision along the X axis.
Position = new Vector2(Position.X + depth.X, Position.Y);
// Perform further collisions with the new bounds.
bounds = BoundingRectangle;
}
}
}
}
}
// Save the new bounds bottom.
previousBottom = bounds.Bottom;
}