/// <summary>
/// Returns the block that the users mouse is hovering over.
/// The rules are that
/// </summary>
/// <param name="collidingBlock">The position of the block that collided with the ChunkTracer.</param>
/// <param name="behaviour">The behaviour that defines the rules of hit testing.</param>
/// <returns>If the raytrace returned any blocks.</returns>
public static bool TryHitTestBlock(CollisionBehaviour behaviour, [NotNull] ChunkTracer tracer, out BlockPosition collidingBlock)
{
switch (behaviour)
{
case CollisionBehaviour.Player:
return(TryHitTestPlayer(tracer, out collidingBlock));
case CollisionBehaviour.Editor:
return(TryHitTestEditor(tracer, out collidingBlock));
default:
throw new ArgumentOutOfRangeException("behaviour");
}
}
static bool TryHitTestPlayer([NotNull] ChunkTracer tracer, out BlockPosition position)
{
foreach (var data in tracer)
{
if (data.Blocks == null || data.Positions == null)
{
continue;
}
for (var i = 0; i < data.Blocks.Count; i++)
{
var block = data.Blocks[i];
if (block.ID == 0 || block.Info.State == BlockState.FLUID)
{
continue;
}
position = new BlockPosition(data.ChunkPosition, data.Positions[i], data.Size);
return(true);
}
}
position = default(BlockPosition);
return(false);
}
static bool TryHitTestEditor([NotNull] ChunkTracer tracer, out BlockPosition position)
{
bool exitedSolid = false;
bool exitedAir = false;
bool includeLiquids = false;
bool firstEnumeration = true;
foreach (var traceData in tracer)
{
// determine if we include liquids by checking if the block we start at is also a liquid
if (firstEnumeration)
{
if (traceData.Blocks == null)
{
// trace started in a non-generated chunk, which visually is air. IncludeLiquids = false
firstEnumeration = false;
}
else
{
var firstBlock = traceData.Blocks.FirstOrDefault();
includeLiquids = firstBlock == null || firstBlock.Info.State != BlockState.FLUID;
firstEnumeration = false;
}
}
if (traceData.Positions == null || traceData.Blocks == null)
{
continue;
}
for (var i = 0; i < traceData.Blocks.Count; i++)
{
var block = traceData.Blocks[i];
// enumerate until it isn't a solid
if (!exitedSolid)
{
if (block.Info.State != BlockState.SOLID)
{
exitedSolid = true;
}
else
{
continue;
}
}
// enumerate until it isn't air
if (!exitedAir)
{
if (block.ID != 0)
{
exitedAir = true;
}
else
{
continue;
}
}
if (includeLiquids)
{
// enumerate to any block that isn't air
if (block.ID == 0)
{
continue;
}
position = new BlockPosition(traceData.ChunkPosition, traceData.Positions[i], traceData.Size);
return(true);
}
// enumerate to the first solid or nonsolid
if (block.Info.State == BlockState.FLUID || block.ID == 0)
{
continue;
}
position = new BlockPosition(traceData.ChunkPosition, traceData.Positions[i], traceData.Size);
return(true);
}
}
position = new BlockPosition();
return(false);
}
