Naive mesh representation

vertlist.py

import euclid
from euclid import Vector3

# naive first attempt at a mesh representation
# a straight list of vertices


class Mesh:

	def __init__(self, vertices=[]):
		"""Initialises a vertex with a list of faces. One 3-tuple of vertices per face."""
		self.vertex_list = vertices

	def __len__(self):
		"""Returns the number of vertice in a mesh"""
		return len(self.vertex_list)

	def vertices(self):
		"""Iterate over the vertices in the mesh"""
		for v in [item for sublist in self.vertices for item in sublist]:
			yield v

	def faces(self):
		"""Iterate over the faces in the mesh"""
		face_iter = iter(self.vertex_list)
		for face in face_iter:
			yield face

	def __str__(self):
		"""Print a readable description of the mesh"""
		result = "Mesh with {0} vertices and {1} faces\n".format(
			len(self.vertex_list), len(self.vertex_list) / 3)
		for face_index, face in enumerate(self.faces()):
			a, b, c = face[0], face[1], face[2]
			result += "Face {0} :({1}, {2}, {3})\n".format(face_index, a, b, c)
		return result


if __name__ == "__main__":
	cube_vertex = [
		# face vertices
		Vector3(-1.0, -1.0, -1.0),
		Vector3(-1.0, 1.0, -1.0),
		Vector3(1.0, 1.0, -1.0),
		Vector3(1.0, -1.0, -1.0),
		Vector3(-1.0, -1.0, 1.0),
		Vector3(-1.0, 1.0, 1.0),
		Vector3(1.0, 1.0, 1.0),
		Vector3(1.0, -1.0, 1.0),
	]
	cube_indices = [
		# Front face
		0, 1, 2,
		0, 2, 3,
		# Back face
		4, 6, 5,
		4, 7, 6,
		# Left face
		4, 5, 1,
		4, 1, 0,
		# Right face
		3, 2, 6,
		3, 6, 7,
		# Top face
		1, 5, 6,
		1, 6, 2,
		# Bottom face
		4, 0, 3,
		4, 3, 7
	]
	cube_face_iter = iter(cube_indices)
	cube_vertex_list = []
	for (ia, ib, ic) in zip(cube_face_iter, cube_face_iter, cube_face_iter):
		cube_face = (cube_vertex[ia], cube_vertex[ib], cube_vertex[ic])
		cube_vertex_list.append(cube_face)
	cube_mesh = Mesh(vertices = cube_vertex_list)
	print(cube_mesh)