(Yeah, just the cuboid selector, but for polygons)
Featuring a super simple and clear in-game polygon viewing thingo:

Downloads:
Hastebin: https://one.denizenscript.com/haste/79948 <-- Most users, just click here and click "Download the script"
GitHub: https://github.com/mcmonkeyprojects/Den ... n_tool.dsc
# Installation:
# Just put the script in your scripts folder and reload.
#
# Usage:
# Type command "/ptool" to get a polygon selector tool.
# While holding the tool, left click to start a selection and right click to expand the selection.
# Requires permission "polygontool.pool"
#
# Use "/pheight (y)" to expand the Y range of the polygon.
# Requires permission "polygontool.pheight"
#
# Use "/pnote [name]" to note your selected polygon as the name. For example, "/pnote myshop" adds noted polygon 'myshop'.
# Requires permission "polygontool.pnote"
#
# Use "/pshow" to show your current polygon selection.
# Requirers permission "polygontool.pshow"
#
# In a script or "/ex" command, use "<player.has_flag[ptool_selection]>" to check if the player has a selection.
# and "<player.flag[ptool_selection]>" to get the selected polygon.