Files
2026-03-17 14:58:51 -06:00

113 lines
4.3 KiB
Python

# MIT License
#
# Copyright (C) 2025 Ryan L. Guy & Dennis Fassbaender
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
import ctypes
import array
import struct
class TriangleMesh_t(ctypes.Structure):
_fields_ = [("vertices", ctypes.c_void_p),
("triangles", ctypes.c_void_p),
("num_vertices", ctypes.c_int),
("num_triangles", ctypes.c_int)]
class TriangleMesh(object):
def __init__(self):
self.vertices = array.array('f', [])
self.triangles = array.array('i', [])
@classmethod
def from_bobj(cls, bobj_data):
int_data, bobj_data = bobj_data[:4], bobj_data[4:]
num_vertices = struct.unpack('i', int_data)[0]
num_floats = 3 * num_vertices
num_bytes = 4 * num_floats
vertex_data, bobj_data = bobj_data[:num_bytes], bobj_data[num_bytes:]
vertices = list(struct.unpack('{0}f'.format(num_floats), vertex_data))
int_data, bobj_data = bobj_data[:4], bobj_data[4:]
num_triangles = struct.unpack('i', int_data)[0]
num_ints = 3 * num_triangles
num_bytes = 4 * num_ints
triangle_data, bobj_data = bobj_data[:num_bytes], bobj_data[num_bytes:]
triangles = list(struct.unpack('{0}i'.format(num_ints), triangle_data))
self = cls()
self.vertices = array.array('f', vertices)
self.triangles = array.array('i', triangles)
return self
def to_bobj(self):
num_vertices = len(self.vertices) // 3
num_triangles = len(self.triangles) // 3
datastr = struct.pack('i', num_vertices)
datastr += self.vertices.tobytes()
datastr += struct.pack('i', num_triangles)
datastr += self.triangles.tobytes()
return datastr
def to_struct(self):
num_vertices = len(self.vertices) // 3
num_triangles = len(self.triangles) // 3
vertex_data = (ctypes.c_float * len(self.vertices))()
for i in range(len(self.vertices)):
vertex_data[i] = self.vertices[i]
triangle_data = (ctypes.c_int * len(self.triangles))()
for i in range(len(self.triangles)):
triangle_data[i] = self.triangles[i]
struct = TriangleMesh_t()
struct.vertices = ctypes.cast(vertex_data, ctypes.c_void_p)
struct.triangles = ctypes.cast(triangle_data, ctypes.c_void_p)
struct.num_vertices = num_vertices
struct.num_triangles = num_triangles
return struct
def apply_transform(self, matrix_world):
m = matrix_world
for i in range(0, len(self.vertices), 3):
v = [self.vertices[i + 0], self.vertices[i + 1], self.vertices[i + 2], 1]
self.vertices[i + 0] = v[0]*m[0] + v[1]*m[1] + v[2]*m[2] + v[3]*m[3]
self.vertices[i + 1] = v[0]*m[4] + v[1]*m[5] + v[2]*m[6] + v[3]*m[7]
self.vertices[i + 2] = v[0]*m[8] + v[1]*m[9] + v[2]*m[10] + v[3]*m[11]
def translate(self, tx, ty, tz):
for i in range(0, len(self.vertices), 3):
self.vertices[i + 0] += tx
self.vertices[i + 1] += ty
self.vertices[i + 2] += tz
def scale(self, scale):
for i in range(0, len(self.vertices), 3):
self.vertices[i + 0] *= scale
self.vertices[i + 1] *= scale
self.vertices[i + 2] *= scale