// TODO: There's a lot of code replication here, perhaps it can be consolidated
/// <summary>
/// Performs terrain collision tests and adjusts the X-axis velocity accordingly
/// </summary>
/// <returns>True if the entity collides with the terrain</returns>
private bool AdjustVelocityX(IAABBEntity entity, World world, out Vector3 collision, out Vector3 collisionDirection)
{
collision = Vector3.Zero;
collisionDirection = Vector3.Zero;
if (entity.Velocity.X == 0)
return false;
// Do some enviornment guessing to improve speed
int minY = (int)entity.Position.Y - (entity.Position.Y < 0 ? 1 : 0);
int maxY = (int)(entity.Position.Y + entity.Size.Width) - (entity.Position.Y < 0 ? 1 : 0);
int minZ = (int)entity.Position.Z - (entity.Position.Z < 0 ? 1 : 0);
int maxZ = (int)(entity.Position.Z + entity.Size.Depth) - (entity.Position.Z < 0 ? 1 : 0);
int minX, maxX;
// Expand bounding box to include area to be tested
if (entity.Velocity.X < 0)
{
TempBoundingBox = new BoundingBox(
new Vector3(entity.BoundingBox.Min.X + entity.Velocity.X, entity.BoundingBox.Min.Y, entity.BoundingBox.Min.Z) - (entity.Size / 2),
new Vector3(entity.BoundingBox.Max.X, entity.BoundingBox.Max.Y, entity.BoundingBox.Max.Z) - (entity.Size / 2));
maxX = (int)(TempBoundingBox.Max.X);
minX = (int)(TempBoundingBox.Min.X + entity.Velocity.X);
}
else
{
TempBoundingBox = new BoundingBox(entity.BoundingBox.Min - (entity.Size / 2), new Vector3(
entity.BoundingBox.Max.X + entity.Velocity.X, entity.BoundingBox.Max.Y, entity.BoundingBox.Max.Z) - (entity.Size / 2));
minX = (int)(entity.BoundingBox.Min.X);
maxX = (int)(entity.BoundingBox.Max.X + entity.Velocity.X);
}
// Do terrain checks
double? collisionPoint = null;
BoundingBox blockBox;
for (int x = minX; x <= maxX; x++)
{
for (int y = minY; y <= maxY; y++)
{
for (int z = minZ; z <= maxZ; z++)
{
var position = new Vector3(x, y, z);
var blockId = world.GetBlockId(position);
var boundingBox = Block.GetBoundingBox(blockId);
if (boundingBox == null)
continue;
blockBox = new BoundingBox(boundingBox.Value.Min + position,
boundingBox.Value.Max + position);
if (TempBoundingBox.Intersects(blockBox))
{
if (entity.Velocity.X < 0)
{
if (!collisionPoint.HasValue)
collisionPoint = blockBox.Max.X;
else if (collisionPoint.Value < blockBox.Max.X)
collisionPoint = blockBox.Max.X;
}
else
{
if (!collisionPoint.HasValue)
collisionPoint = blockBox.Min.X;
else if (collisionPoint.Value > blockBox.Min.X)
collisionPoint = blockBox.Min.X;
}
collision = position;
}
}
}
}
if (collisionPoint != null)
{
if (entity.Velocity.X < 0)
{
entity.Velocity = new Vector3(
entity.Velocity.X - (TempBoundingBox.Min.X - collisionPoint.Value),
entity.Velocity.Y,
entity.Velocity.Z);
collisionDirection = Vector3.Left;
}
else if (entity.Velocity.X > 0)
{
entity.Velocity = new Vector3(
entity.Velocity.X - (TempBoundingBox.Max.X - collisionPoint.Value),
entity.Velocity.Y,
entity.Velocity.Z);
collisionDirection = Vector3.Right;
}
return true;
}
return false;
}
/// <summary>
/// Performs terrain collision tests and adjusts the Y-axis velocity accordingly
/// </summary>
/// <returns>True if the entity collides with the terrain</returns>
private bool AdjustVelocityY(IAABBEntity entity, World world, out Vector3 collision, out Vector3 collisionDirection)
{
collision = Vector3.Zero;
collisionDirection = Vector3.Zero;
if (entity.Velocity.Y == 0)
return false;
// Do some enviornment guessing to improve speed
int minX = (int)entity.Position.X - (entity.Position.X < 0 ? 1 : 0);
int maxX = (int)(entity.Position.X + entity.Size.Width) - (entity.Position.X < 0 ? 1 : 0);
int minZ = (int)entity.Position.Z - (entity.Position.Z < 0 ? 1 : 0);
int maxZ = (int)(entity.Position.Z + entity.Size.Depth) - (entity.Position.Z < 0 ? 1 : 0);
int minY, maxY;
// Expand bounding box to include area to be tested
if (entity.Velocity.Y < 0)
{
TempBoundingBox = new BoundingBox(
new Vector3(entity.BoundingBox.Min.X, entity.BoundingBox.Min.Y + entity.Velocity.Y, entity.BoundingBox.Min.Z) - (entity.Size / 2),
new Vector3(entity.BoundingBox.Max.X, entity.BoundingBox.Max.Y, entity.BoundingBox.Max.Z) - (entity.Size / 2));
maxY = (int)(TempBoundingBox.Max.Y);
minY = (int)(TempBoundingBox.Min.Y + entity.Velocity.Y);
}
else
{
TempBoundingBox = new BoundingBox(entity.BoundingBox.Min - (entity.Size / 2), new Vector3(
entity.BoundingBox.Max.X, entity.BoundingBox.Max.Y + entity.Velocity.Y, entity.BoundingBox.Max.Z) - (entity.Size / 2));
minY = (int)(entity.BoundingBox.Min.Y);
maxY = (int)(entity.BoundingBox.Max.Y + entity.Velocity.Y);
}
// Clamp Y into map boundaries
if (minY < 0) minY = 0; if (minY >= World.Height) minY = World.Height - 1;
if (maxY < 0) maxY = 0; if (maxY >= World.Height) maxY = World.Height - 1;
// Do terrain checks
double? collisionPoint = null;
BoundingBox blockBox;
for (int x = minX; x <= maxX; x++)
{
for (int y = minY; y <= maxY; y++)
{
for (int z = minZ; z <= maxZ; z++)
{
var position = new Vector3(x, y, z);
var blockId = world.GetBlockId(position);
var boundingBox = Block.GetBoundingBox(blockId);
if (boundingBox == null)
continue;
blockBox = new BoundingBox(boundingBox.Value.Min + position,
boundingBox.Value.Max + position);
if (TempBoundingBox.Intersects(blockBox))
{
if (entity.Velocity.Y < 0)
{
if (!collisionPoint.HasValue)
collisionPoint = blockBox.Max.Y;
else if (collisionPoint.Value < blockBox.Max.Y)
collisionPoint = blockBox.Max.Y;
}
else
{
if (!collisionPoint.HasValue)
collisionPoint = blockBox.Min.Y;
else if (collisionPoint.Value > blockBox.Min.Y)
collisionPoint = blockBox.Min.Y;
}
collision = position;
}
}
}
}
if (collisionPoint != null)
{
if (entity.Velocity.Y < 0)
{
// TODO: Do block event
//var block = world.GetBlock(collision);
//block.OnBlockWalkedOn(world, collision, this);
entity.Velocity = new Vector3(entity.Velocity.X,
entity.Velocity.Y + (collisionPoint.Value - TempBoundingBox.Min.Y),
entity.Velocity.Z);
collisionDirection = Vector3.Down;
}
else if (entity.Velocity.Y > 0)
{
entity.Velocity = new Vector3(entity.Velocity.X,
entity.Velocity.Y - (TempBoundingBox.Max.Y - collisionPoint.Value),
entity.Velocity.Z);
collisionDirection = Vector3.Up;
}
return true;
}
return false;
}
internal static void DefaultBlockUpdateHandler(BlockDescriptor block, World world, Coordinates3D updatedBlock)
{
var logic = GetLogicDescriptor(block);
var support = logic.GetSupportDirection(block, world, updatedBlock);
var supportingBlock = updatedBlock;
switch (support)
{
case SupportDirection.Down:
supportingBlock = updatedBlock + Coordinates3D.Down;
break;
case SupportDirection.Up:
supportingBlock = updatedBlock + Coordinates3D.Up;
break;
case SupportDirection.East:
supportingBlock = updatedBlock + Coordinates3D.East;
break;
case SupportDirection.West:
supportingBlock = updatedBlock + Coordinates3D.West;
break;
case SupportDirection.North:
supportingBlock = updatedBlock + Coordinates3D.North;
break;
case SupportDirection.South:
supportingBlock = updatedBlock + Coordinates3D.South;
break;
default:
return;
}
if (!World.IsValidPosition(supportingBlock))
return;
if (world.GetBlockId(supportingBlock) == 0) // TODO: Air isn't the only thing that can't support some blocks
OnBlockMined(block, world, updatedBlock, null); // TODO: Consider using a seperate delegate for blocks destroyed through non-player actions
}
public static void OnItemUsedOnBlock(ItemDescriptor item, World world, Coordinates3D clickedBlock, Coordinates3D clickedSide, Coordinates3D cursorPosition)
{
if (world.GetBlockId(clickedBlock + clickedSide) == 0)
world.SetBlockId(clickedBlock + clickedSide, CakeBlock.BlockId);
}
internal static void DefaultBlockPlacedHandler(BlockDescriptor block, World world, Coordinates3D clickedBlock, Coordinates3D clickedSide, Coordinates3D cursorPosition)
{
if (world.GetBlockId(clickedBlock + clickedSide) == 0) // TODO: There are more situations than just air when a block can be overwritten
{
world.SetBlockId(clickedBlock + clickedSide, block.Id);
world.SetMetadata(clickedBlock + clickedSide, block.Metadata);
}
}
