scriptnig grease pencli

fafafufu.py

'''
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
'''

import math
import bpy


def get_layer(gdata_owner, layer_name):

    grease_data = bpy.data.grease_pencil
    if gdata_owner not in grease_data:
        gp = grease_data.new(gdata_owner)
    else:
        gp = grease_data[gdata_owner]

    # get grease pencil layer
    if not (layer_name in gp.layers):
        layer = gp.layers.new(layer_name)
        layer.frames.new(1)
        layer.line_width = 1
    else:
        layer = gp.layers[layer_name]
        layer.frames[0].clear()

    return layer


def generate_gp3d_stroke(layer):
    layer.show_points = True
    layer.color = (0.2, 0.90, .2)
    s = layer.frames[0].strokes.new()
    s.draw_mode = '3DSPACE'

    chain = []
    num_verts = 10
    r = 2.2
    gamma = 2 * math.pi / num_verts
    for i in range(num_verts+1):
        theta = gamma * i
        world_point = (math.sin(theta) * r, math.cos(theta) * r, 1.2)
        chain.append(world_point)

    s.points.add(len(chain))
    for idx, p in enumerate(chain):
        s.points[idx].co = p


class TrigGenerator(bpy.types.Operator):

    bl_idname = 'mesh.trig_generator'
    bl_label = 'generated trig with gpencil'
    bl_options = {'REGISTER', 'UNDO'}

    def execute(self, context):
        obj = bpy.context.object
        data_name = 'stack_data'
        layer_name = "stack layer"
        layer = get_layer(data_name, layer_name)
        generate_gp3d_stroke(layer)
        bpy.context.scene.grease_pencil = bpy.data.grease_pencil[data_name]
        return {'FINISHED'}


def register():
    bpy.utils.register_class(TrigGenerator)


def unregister():
    bpy.utils.unregister_class(TrigGenerator)


if __name__ == '__main__':
    register()