add_mesh_star.py

# add_mesh_star.py Copyright (C) 2008-2009, FourMadMen.com
#
# add star to the blender 2.50 add->mesh menu
# ***** 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
#
# ***** END GPL LICENCE BLOCK *****

bl_addon_info = {
    'name': 'Add Mesh: Star',
    'author': 'fourmadmen',
    'version': '2.1',
    'blender': (2, 5, 3),
    'location': 'View3D > Add > Mesh ',
    'description': 'Adds a mesh Star to the Add Mesh menu',
    'url': 'http://wiki.blender.org/index.php/Extensions:2.5/Py/' \
        'Scripts/Add_Mesh/Add_Star',
    'category': 'Add Mesh'}


import bpy
import mathutils
from mathutils import Vector, Quaternion
from math import pi
from bpy.props import IntProperty, FloatProperty, BoolProperty


# Stores the values of a list of properties and the
# operator id in a property group ('recall_op') inside the object.
# Could (in theory) be used for non-objects.
# Note: Replaces any existing property group with the same name!
# ob ... Object to store the properties in.
# op ... The operator that should be used.
# op_args ... A dictionary with valid Blender
#             properties (operator arguments/parameters).
def store_recall_properties(ob, op, op_args):
    if ob and op and op_args:
        recall_properties = {}

        # Add the operator identifier and op parameters to the properties.
        recall_properties['op'] = op.bl_idname
        recall_properties['args'] = op_args

        # Store new recall properties.
        ob['recall'] = recall_properties


# Apply view rotation to objects if "Align To" for
# new objects was set to "VIEW" in the User Preference.
def apply_object_align(context, ob):
    obj_align = bpy.context.user_preferences.edit.object_align

    if (context.space_data.type == 'VIEW_3D'
        and obj_align == 'VIEW'):
            view3d = context.space_data
            region = view3d.region_3d
            viewMatrix = region.view_matrix
            rot = viewMatrix.rotation_part()
            ob.rotation_euler = rot.invert().to_euler()


# Create a new mesh (object) from verts/edges/faces.
# verts/edges/faces ... List of vertices/edges/faces for the
#                       new mesh (as used in from_pydata).
# name ... Name of the new mesh (& object).
# edit ... Replace existing mesh data.
# Note: Using "edit" will destroy/delete existing mesh data.
def create_mesh_object(context, verts, edges, faces, name, edit):
    scene = context.scene
    obj_act = scene.objects.active

    # Can't edit anything, unless we have an active obj.
    if edit and not obj_act:
        return None

    # Create new mesh
    mesh = bpy.data.meshes.new(name)

    # Make a mesh from a list of verts/edges/faces.
    mesh.from_pydata(verts, edges, faces)

    # Update mesh geometry after adding stuff.
    mesh.update()

    # Deselect all objects.
    bpy.ops.object.select_all(action='DESELECT')

    if edit:
        # Replace geometry of existing object

        # Use the active obj and select it.
        ob_new = obj_act
        ob_new.selected = True

        if obj_act.mode == 'OBJECT':
            # Get existing mesh datablock.
            old_mesh = ob_new.data

            # Set object data to nothing
            ob_new.data = None

            # Clear users of existing mesh datablock.
            old_mesh.user_clear()

            # Remove old mesh datablock if no users are left.
            if (old_mesh.users == 0):
                bpy.data.meshes.remove(old_mesh)

            # Assign new mesh datablock.
            ob_new.data = mesh

    else:
        # Create new object
        ob_new = bpy.data.objects.new(name, mesh)

        # Link new object to the given scene and select it.
        scene.objects.link(ob_new)
        ob_new.selected = True

        # Place the object at the 3D cursor location.
        ob_new.location = scene.cursor_location

        apply_object_align(context, ob_new)

    if obj_act and obj_act.mode == 'EDIT':
        if not edit:
            # We are in EditMode, switch to ObjectMode.
            bpy.ops.object.mode_set(mode='OBJECT')

            # Select the active object as well.
            obj_act.selected = True

            # Apply location of new object.
            scene.update()

            # Join new object into the active.
            bpy.ops.object.join()

            # Switching back to EditMode.
            bpy.ops.object.mode_set(mode='EDIT')

            ob_new = obj_act

    else:
        # We are in ObjectMode.
        # Make the new object the active one.
        scene.objects.active = ob_new

    return ob_new


# A very simple "bridge" tool.
# Connects two equally long vertex rows with faces.
# Returns a list of the new faces (list of  lists)
#
# vertIdx1 ... First vertex list (list of vertex indices).
# vertIdx2 ... Second vertex list (list of vertex indices).
# closed ... Creates a loop (first & last are closed).
# flipped ... Invert the normal of the face(s).
#
# Note: You can set vertIdx1 to a single vertex index to create
#       a fan/star of faces.
# Note: If both vertex idx list are the same length they have
#       to have at least 2 vertices.
def createFaces(vertIdx1, vertIdx2, closed=False, flipped=False):
    faces = []

    if not vertIdx1 or not vertIdx2:
        return None

    if len(vertIdx1) < 2 and len(vertIdx2) < 2:
        return None

    fan = False
    if (len(vertIdx1) != len(vertIdx2)):
        if (len(vertIdx1) == 1 and len(vertIdx2) > 1):
            fan = True
        else:
            return None

    total = len(vertIdx2)

    if closed:
        # Bridge the start with the end.
        if flipped:
            face = [
                vertIdx1[0],
                vertIdx2[0],
                vertIdx2[total - 1]]
            if not fan:
                face.append(vertIdx1[total - 1])
            faces.append(face)

        else:
            face = [vertIdx2[0], vertIdx1[0]]
            if not fan:
                face.append(vertIdx1[total - 1])
            face.append(vertIdx2[total - 1])
            faces.append(face)

    # Bridge the rest of the faces.
    for num in range(total - 1):
        if flipped:
            if fan:
                face = [vertIdx2[num], vertIdx1[0], vertIdx2[num + 1]]
            else:
                face = [vertIdx2[num], vertIdx1[num],
                    vertIdx1[num + 1], vertIdx2[num + 1]]
            faces.append(face)
        else:
            if fan:
                face = [vertIdx1[0], vertIdx2[num], vertIdx2[num + 1]]
            else:
                face = [vertIdx1[num], vertIdx2[num],
                    vertIdx2[num + 1], vertIdx1[num + 1]]
            faces.append(face)

    return faces


def add_star(points, outer_radius, inner_radius, height):
    PI_2 = pi * 2
    z_axis = (0, 0, 1)

    verts = []
    faces = []

    segments = points * 2

    half_height = height / 2.0

    vert_idx_top = len(verts)
    verts.append(Vector((0.0, 0.0, half_height)))

    vert_idx_bottom = len(verts)
    verts.append(Vector((0.0, 0.0, -half_height)))

    edgeloop_top = []
    edgeloop_bottom = []

    for index in range(segments):
        quat = Quaternion(z_axis, (index / segments) * PI_2)

        if index % 2:
            # Uneven
            radius = outer_radius
        else:
            # Even
            radius = inner_radius

        edgeloop_top.append(len(verts))
        vec = Vector((radius, 0, half_height)) * quat
        verts.append(vec)

        edgeloop_bottom.append(len(verts))
        vec = Vector((radius, 0, -half_height)) * quat
        verts.append(vec)



    faces_top = createFaces([vert_idx_top], edgeloop_top, closed=True)
    faces_outside = createFaces(edgeloop_top, edgeloop_bottom, closed=True)
    faces_bottom = createFaces([vert_idx_bottom], edgeloop_bottom,
        flipped=True, closed=True)

    faces.extend(faces_top)
    faces.extend(faces_outside)
    faces.extend(faces_bottom)

    return verts, faces


class AddStar(bpy.types.Operator):
    '''Add a star mesh.'''
    bl_idname = "mesh.primitive_star_add"
    bl_label = "Add Star"
    bl_options = {'REGISTER', 'UNDO'}

    # edit - Whether to add or update.
    edit = BoolProperty(name="",
        description="",
        default=False,
        options={'HIDDEN'})
    points = IntProperty(name="Points",
        description="Number of points for the star",
        min=2,
        max=256,
        default=5)
    outer_radius = FloatProperty(name="Outer Radius",
        description="Outer radius of the star",
        min=0.01,
        max=9999.0,
        default=1.0)
    innter_radius = FloatProperty(name="Inner Radius",
        description="Inner radius of the star",
        min=0.01,
        max=9999.0,
        default=0.5)
    height = FloatProperty(name="Height",
        description="Height of the star",
        min=0.01,
        max=9999.0,
        default=0.5)

    def execute(self, context):
        props = self.properties

        verts, faces = add_star(
            props.points,
            props.outer_radius,
            props.innter_radius,
            props.height)

        obj = create_mesh_object(context, verts, [], faces, "Star",
            props.edit)

        # Store 'recall' properties in the object.
        recall_args_list = {
            "edit": True,
            "points": props.points,
            "outer_radius": props.outer_radius,
            "innter_radius": props.innter_radius,
            "height": props.height}
        store_recall_properties(obj, self, recall_args_list)

        return {'FINISHED'}

# Register the operator

menu_func = (lambda self, context: self.layout.operator(AddStar.bl_idname,
                                        text="Star", icon='PLUGIN'))


def register():
    bpy.types.register(AddStar)

    # Add "Star" menu to the "Add Mesh" menu.
    bpy.types.INFO_MT_mesh_add.append(menu_func)


def unregister():
    bpy.types.unregister(AddStar)

    # Remove "Star" menu from the "Add Mesh" menu.
    bpy.types.INFO_MT_mesh_add.remove(menu_func)

if __name__ == "__main__":
    register()