op_object.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 3
#  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 LICENSE BLOCK #####

# <pep8-80 compliant>

# ----------------------------------------------------------------------------
# Object related functionality
from .op_gen import *

# ----------------------------------------------------------------------------

def get_object_bbox_coords(obj):
    """Returns two vectors which contain the minimum and maximum coordinates
    for bounding box for object obj
    """

    # Acknowledgement: Here is nice explanation of obj.bound_box and example
    # for using Blender's bounding box data in python by zeffii:
    # https://blender.stackexchange.com/questions/32283/what-are-all-values-in-bound-box

    worldify = lambda p: obj.matrix_world @ mathutils.Vector(p[:])
    coords = [worldify(p).to_tuple() for p in obj.bound_box[:]]
    rotated = list(zip(*coords[::]))
    min_bbox = [min(c) for c in rotated]
    max_bbox = [max(c) for c in rotated]

    return min_bbox, max_bbox


def get_global_bbox_coords():
    """Returns two vectors which contain the minimum and maximum coordinates
    for bounding box for all mesh objects included in export
    """

    all_mins=[];
    all_maxs=[];
    for obj in bpy.data.objects:
        if obj.type != 'MESH':
            continue
        if not obj.shmg_include_in_export:
            continue

        obj_min_bbox, obj_max_bbox = get_object_bbox_coords(obj)
        all_mins.append(obj_min_bbox)
        all_maxs.append(obj_max_bbox)

    rot_min = zip(*all_mins[::])
    global_min_bbox = [min(c) for c in rot_min]
    rot_max = zip(*all_maxs[::])
    global_max_bbox = [max(c) for c in rot_max]

    return global_min_bbox, global_max_bbox


def block_mesh_cell_count(bb_min, bb_max, gui):
    """Returns number of cells in Block Mesh and updates
    block_mesh_* data in gui. bb_min and bb_max are
    minimum and maximum bounding box coordinates.
    """

    sl = gui.cell_side_length

    for i in range(0, 3):
        bb_min_with_margin = bb_min[i] - sl/2.0
        bb_max_with_margin = bb_max[i] + sl/2.0
        bm_min = math.floor(bb_min_with_margin / sl)
        bm_max = math.ceil(bb_max_with_margin / sl)
        gui.block_mesh_delta[i] = bm_max - bm_min
        gui.block_mesh_min[i] = bm_min * sl
        gui.block_mesh_max[i] = bm_max * sl

    bm_count = gui.block_mesh_delta[0] * \
               gui.block_mesh_delta[1] * \
               gui.block_mesh_delta[2]

    return bm_count

def get_surface_area(obj):
    """Returns surface area of mesh object obj"""

    if obj.type != 'MESH':
        return 0.0

    bm = bmesh.new()
    bm.from_mesh(obj.data)
    bm.transform(obj.matrix_world) # Apply transformation
    bmesh.ops.triangulate(bm, faces=bm.faces) # Triangulate
    area = sum(f.calc_area() for f in bm.faces)
    del bm
    return area


def get_scaled_object_names():
    """Returns string of object names which apply object scaling"""

    ob_names = ""
    for ob in bpy.data.objects:
        if ob.type != 'MESH':
            continue
        if not ob.shmg_include_in_export:
            continue
        if ob.scale != mathutils.Vector((1.0, 1.0, 1.0)):
            ob_names += ob.name + " "
    return ob_names