Plugin for sketch up - with a bug!

plytkowanie.rb

# Wtyczka: "P-ytkuj"
# Autor: Krzysztof Skrzŕtnicki
# Licencja: GPLv3
# Wersja: 1.2

# First we pull in the standard API hooks.
require 'sketchup.rb'

# Show the Ruby Console at startup so we can
# see any programming errors we may make.
Sketchup.send_action "showRubyPanel:"

# Add a menu item to launch our plugin.
UI.menu("PlugIns").add_item("Plytkuj") {
  plytkuj
}

@defaults = ["10","10","40","25","0.2","0.2","1","2.54","0","tak"]
@paramlist = ["","","","","","","","","","tak|nie"]

def plytkuj
	# Get handles to our model and the Entities collection it contains.
	model = Sketchup.active_model
	entities = model.entities
	
	currmat = current = Sketchup.active_model.materials.current
	if (currmat.nil?)
		currmat_name = "BRAK"
	else
		currmat_name = currmat.display_name
	end
	
	# zapytaj o parametry
	prompts = ["Liczba X", "Liczba Y", "Szerokosc X", "Wysokosc Y", "Przerwa X", "Przerwa Y", "Grubosc","Podzielnik","Kat obrotu","Aplikuj aktualny material (" + currmat_name + ")"]
	input = UI.inputbox prompts, @defaults, @paramlist, "Podaj parametry kafelkow"
	
	if (not input)
		return;
	end
	
	@defaults = input
	
	podzielnik = input[7].to_f
	
	count_x = input[0].to_i
	count_y = input[1].to_i
	
	size_x = input[2].to_f / podzielnik
	size_y = input[3].to_f / podzielnik
	
	gap_x = input[4].to_f / podzielnik
	gap_y = input[5].to_f / podzielnik
	
	size_z = input[6].to_f / podzielnik
	
	angle = input[8].to_f
	angle_rad = angle / 1.radians
	
	apply_mat = (input[9] == "tak") && (not currmat.nil?)
	
	t = Geom::Transformation.rotation [0,0,0], [0,0,1], angle_rad
	
	for step_x in 0..(count_x-1)
		for step_y in 0..(count_y-1)
			
			pt1 = [0.0, step_x * (size_x+gap_x), step_y * (size_y+gap_y)]
			pt2 = [0.0, pt1[1], pt1[2] + size_y ]
			pt3 = [0.0, pt1[1]+size_x, pt1[2] + size_y ]
			pt4 = [0.0, pt1[1]+size_x, pt1[2]]
			
			pt1 = t * pt1
			pt2 = t * pt2
			pt3 = t * pt3
			pt4 = t * pt4
		
			grp = entities.add_group
			
			new_face = grp.entities.add_face pt1, pt2, pt3, pt4
			

			if (apply_mat)
                                # the bug is here:
				grp.material = currmat
                                # this works differently and doesn't cause a bug:
                                # new_face.material = currmat
			end
			
			new_face.pushpull size_z
		end
	end
	
end