mesh_select_by_direction.py

# mesh_select_by_direction.py Copyright (C) 2011, Dolf Veenvliet
#
# Extrude a selection from a mesh multiple times
#
# ***** BEGIN GPL LICENSE BLOCK *****
#
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software Foundation,
# Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
#
# ***** END GPL LICENCE BLOCK *****
'''
bl_info = {
    "name": "Select by direction",
    "author": "Dolf Veenvliet",
    "version": (1,),
    "blender": (2, 56, 0),
    "location": "View3D > Select",
    "description": "Select all items whose normals face a certain direction",
    "warning": "",
    "wiki_url": "",
    "tracker_url": "",
    "category": "Mesh"}

"""
Usage:

Launch from from "Select -> By direction"

Additional links:
	Author Site: http://www.macouno.com
	e-mail: dolf {at} macouno {dot} com
"""
'''
import bpy, mathutils, math
from bpy.props import FloatVectorProperty, FloatProperty, BoolProperty, EnumProperty


class Select_by_direction():

	# Initialise the class
	def __init__(self, context, direction, divergence, extend, space):

		self.ob = context.active_object
		bpy.ops.object.mode_set(mode='OBJECT')

		self.space = space

		# if we do stuff in global space we need to object matrix
		if self.space == 'GLO':
			direction = mathutils.Vector(direction) * mathutils.Matrix(self.ob.matrix_world.rotation_part()).invert()
		else:
			direction = mathutils.Vector(direction)

		direction = direction.normalized()

		vertSelect = bpy.context.tool_settings.mesh_select_mode[0]
		edgeSelect = bpy.context.tool_settings.mesh_select_mode[1]
		faceSelect = bpy.context.tool_settings.mesh_select_mode[2]

		if mathutils.Vector(direction).length:

			# Vert select
			if vertSelect:

				hasSelected = self.hasSelected(self.ob.data.vertices)

				for v in self.ob.data.vertices:

					normal = v.normal

					s = self.selectCheck(v.select, hasSelected, extend)
					d = self.deselectCheck(v.select, hasSelected, extend)

					if s or d:
						angle = direction.angle(normal)

					# Check if the verts match any of the directions
					if s and angle <= divergence:
						v.select = True

					if d and angle > divergence:
						v.select = False

			# Edge select
			if edgeSelect:

				hasSelected = self.hasSelected(self.ob.data.edges)

				for e in self.ob.data.edges:

					s = self.selectCheck(e.select, hasSelected, extend)
					d = self.deselectCheck(e.select, hasSelected, extend)


					# Check if the edges match any of the directions
					if s or d:
						normal = self.ob.data.vertices[e.vertices[0]].normal
						normal += self.ob.data.vertices[e.vertices[1]].normal

						angle =direction.angle(normal)


					if s and angle <= divergence:
						e.select = True

					if d and angle > divergence:
						e.select = False

			# Face select
			if faceSelect:

				hasSelected = self.hasSelected(self.ob.data.polygons)

				# Loop through all the given faces
				for f in self.ob.data.polygons:

					s = self.selectCheck(f.select, hasSelected, extend)
					d = self.deselectCheck(f.select, hasSelected, extend)

					if s or d:
						angle = direction.angle(f.normal)

					# Check if the faces match any of the directions
					if s and angle <= divergence:
						f.select = True

					if d and angle > divergence:
						f.select = False

		bpy.ops.object.mode_set(mode='EDIT')



	# See if the current item should be selected or not
	def selectCheck(self, isSelected, hasSelected, extend):

		# If the current item is not selected we may want to select
		if not isSelected:

			# If we are extending or nothing is selected we want to select
			if extend or not hasSelected:
				return True

		return False



	# See if the current item should be deselected or not
	def deselectCheck(self, isSelected, hasSelected, extend):

		# If the current item is selected we may want to deselect
		if isSelected:

			# If something is selected and we're not extending we want to deselect
			if hasSelected and not extend:
				return True

		return False



	# See if there is at least one selected item
	def hasSelected(self, items):

		for item in items:
			if item.select:
				return True

		return False



class Select_init(bpy.types.Operator):
	'''Select all items with normals facing a certain direction'''
	bl_idname = 'mesh.select_by_direction'
	bl_label = 'Select by direction'
	bl_options = {'REGISTER', 'UNDO'}

	direction = FloatVectorProperty(name="Direction", description="Direction as a vector", default=(0.0, 0.0, 1.0), min=-100.0, max=100.0, soft_min=-10.0, soft_max=10.0, step=100, precision=2)

	divergence = FloatProperty(name='Divergence', description='The nr of degrees the selection may differ from the vector', default=math.radians(30.0), min=0.0, max=math.radians(360.0), soft_min=0.0, soft_max=math.radians(360.0), step=math.radians(5000), precision=2, subtype='ANGLE')

	extend = BoolProperty(name='Extend', description='Extend the current selection', default=False)

	# The spaces we use
	spaces=(('LOC', 'Local', ''),('GLO', 'Global', ''))

	space = EnumProperty(items=spaces, name='Space', description='The space to interpret the directions in', default='LOC')

	@classmethod
	def poll(cls, context):
		obj = context.active_object
		return (obj and obj.type == 'MESH')

	def execute(self, context):
		SELECT_DIRECTION = Select_by_direction(context, self.direction, self.divergence, self.extend, self.space)
		return {'FINISHED'}