Bukkit

Description: ProjectileTrajectory allows you to draw the trajectory of projectiles like snowballs or eggs.

Bows are supported as well. For example: If you want to calculate the trajectory of a snowball, you just have to hold it in your hand and the trajectory will be rendered using particles. It is possible to select certain particles for every type of projectile, e.g. green sparks for potions and hearts for snowballs...

Note: The trajectory is only shown to the aiming user.

New source location: https://github.com/JannST/projectile-trajectory

GUI:
Open the GUI with /trajectory or /tra
In the GUI you can:
- enable/disable trajectories
- enable/disable trajectories for certain projectiles
- customize trajectories with particles and colors
- set the minimal distance between you and the trajectory (useful when particles like largeexplode are used)

Main Menu

Projectile customization menu (Arrow)
Note: Color selection is only available for redstone and spell partilces

Permissions:
The main permission is: projectiletrajectory.use
If you disallowed particle changing in the config and you want to it allow it to certain users nevertheless, use: projectiletrajectory.change
Note: It could be possible, that you have to relog after the permission were added.

Commands:
/trajectory or /tra are the only commands.

Configuartion:
Main configuation file (config.yml) I think this should be self explaining, but if there are questions, feel free to ask :)

Default player configuration (DefaultPlayerConfig.yml)
This file contains the default settings every player will get, when he uses the plugin for the first time. These settings can always be changed through the menu.

List of possible particles:
- reddust (colorable)
- fireworksSpark
- magicCrit
- mobSpell (colorable)
- smoke
- flame
- largeexplode
- lava
- cloud
- heart
- happyVillager
- dripWater
- dripLava
- crit

List of possible colors:
- white
- orange
- magenta
- blue
- yellow
- lime
- pink
- darkgray
- gray
- cyan
- purple
- darkblue
- brown
- green
- red
- black

Metrics:
This plugin uses plugin metrics, because I like to see, how it is used. :)

Special Thanks:
@DarkBlade12 I used your ParticleEffect Library. Very nice to use and well written. Thanks for that. :) https:github.com/DarkBlade12/ParticleEffect

Source:
https:bitbucket.org/JanST/projectiletrajectory/src

Note: The plugin was tested with spigot version: git-Spigot-5818108-a486600 (MC: 1.8.4) (Implementing API version 1.8.4-R0.1-SNAPSHOT)

I published this plugin initially on spigotmc.org, if there are any problems, make sure to look for a solution there as well.