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  1. Minecraft: Java Edition
  2. MC-80142

Wither skulls and small/dragon fireballs move raggedly when summoned

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Details

    • Bug
    • Status: Open
    • Resolution: Unresolved
    • Minecraft 1.8.4, Minecraft 16w36a, Minecraft 1.11.2, Minecraft 17w06a, Minecraft 1.12, Minecraft 1.12.2, Minecraft 18w02a, Minecraft 18w05a, Minecraft 18w11a, Minecraft 18w21a, Minecraft 1.13-pre1, Minecraft 1.13.1, 1.15.2, 20w51a, 21w05b, 1.17.1, 22w07a, 1.18.2, 22w14a, 22w15a, 22w16b, 22w17a, 22w18a, 22w19a, 1.19 Pre-release 1, 1.19 Pre-release 2, 1.19 Pre-release 4, 1.19 Pre-release 5, 1.19 Release Candidate 2, 1.19, 22w24a, 1.19.1 Pre-release 1
    • None
    • Confirmed
    • Entities, Projectiles
    • Low

    Description

      The bug

      Wither skulls and small/dragon fireballs will stutter during flight if their power tag does not have a magnitude of either 0 or 0.1.

      To reproduce

      /summon minecraft:wither_skull ~ ~2 ~ {Motion:[0.0,0.0,0.5],power:[0.2d,0d,0d]}
      

      Details

      The client assumes all non-Ghast fireballs (including both types of wither skulls) have a power of magnitude 0.1 when calculating their acceleration, while on the server the value is stored properly. The only exception to this is when the magnitude is 0, in which case the entity behaves properly according it its Motion; I assume the acceleration calculation is either being skipped or doing nothing (as in Unity when Transform.LookAt receives the executor) in this case. The game will re-sync the entity's position every second or so, creating jerky movement for any affected entity whose power magnitude is not equal to 0 or 0.1.

      Reloading the projectile will update power's direction on the client (if it has been modified with /data), but its magnitude will still be interpreted as 0.1 (unless it is 0). I imagine (and would hope that) any fix to the previous paragraph would fix this as well, although if not the devs are within their rights to call it WF and make me sad.

      So to summarize, due to this bug, for a summoned non-Ghast fireball to move smoothly it must be summoned with a power magnitude of either:

      • 0, in which case it will experience drag but can be redirected easily by modifying its Motion tag.
      • 0.1, in which case it will quickly accelerate/decelerate (depending on its Motion) to its (fixed) terminal velocity and can only redirected buglessly by having its power modified and then being reloaded.

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              Unassigned Unassigned
              clamlol clam lol
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              Dates

                Created:
                Updated:
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