[Forge 1.12.2] Dot product between vectors keep decreasing when the player's vector is near the entity's vetor

[lethinh]

I'm currently working on a block that its tile entity can automatically hit the mob. My problem is when I use the Vec3d dot product check if the entity is in the block tile entity hitbox, I realized that the block tile entity won't hit if the mob goes nearer the block. Here is my code:

 

Spoiler

Vec3d targetVec = target.getPositionVector();
Vec3d playerVec = player.getPositionVector();
Vec3d dir1 = targetVec.subtract(playerVec).normalize();
Vec3d dir2 = player.getLookVec().normalize();
double dot = dir1.dotProduct(dir2);

boolean isInHitbox = dot >= 0.8D; // If it is smaller then the mob is behind the block or not in the hitbox

 

I would greatly appreciated your help! Thanks in advance.

[lethinh]

And btw, it seems like if the mob goes nearer (for about 2 blocks or nearer), the tile entity won't hit the mob

[Draco18s]

10 hours ago, lethinh said:

I use the Vec3d dot product check if the entity is in the block tile entity hitbox

Dot product is not the correct tool here. You want it within range, use a distance check.

[jabelar]

Dot product is mathematical concept that finds the component of one vector that lies along another vector. It is useful for determining if two vectors are mostly in the same direction.