from math import sqrt from ..geometry import Vector from .mesh import Material, MeshPart Vertex = Vector TexCoord = Vertex Normal = Vertex Color = Vertex class FaceVertex: """Contains the information a vertex needs in a face In contains the index of the vertex, the index of the texture coordinate and the index of the normal. It is None if it is not available. :param vertex: index of the vertex :param tex_coord: index of the texture coordinate :param normal: index of the normal :param color: index of the color """ def __init__(self, vertex = None, tex_coord = None, normal = None, color = None): """Initializes a FaceVertex from its indices """ self.vertex = vertex self.tex_coord = tex_coord self.normal = normal self.color = color def from_array(self, arr): """Initializes a FaceVertex from an array :param arr: can be an array of strings, the first value will be the vertex index, the second will be the texture coordinate index, the third will be the normal index, and the fourth will be the color index. """ self.vertex = int(arr[0]) if len(arr) > 0 else None try: self.tex_coord = int(arr[1]) if len(arr) > 1 else None except: self.tex_coord = None try: self.normal = int(arr[2]) if len(arr) > 2 else None except: self.normal = None try: self.color = int(arr[3]) if len(arr) > 3 else None except: self.color = None return self class Face: """Represents a face with 3 vertices Faces with more than 3 vertices are not supported in this class. You should split your face first and then create the number needed of instances of this class. """ def __init__(self, a = None, b = None, c = None, material = None): """Initializes a Face with its three FaceVertex and its Material :param a: first FaceVertex element :param b: second FaceVertex element :param c: third FaceVertex element :param material: the material to use with this face """ self.a = a self.b = b self.c = c self.material = material # Expects array of array def from_array(self, arr): """Initializes a Face with an array :param arr: should be an array of array of objects. Each array will represent a FaceVertex """ self.a = FaceVertex().from_array(arr[0]) self.b = FaceVertex().from_array(arr[1]) self.c = FaceVertex().from_array(arr[2]) return self class ModelParser: """Represents a 3D model """ def __init__(self, up_conversion = None): """Initializes the model :param up_conversion: couple of characters, can be y z or z y """ self.up_conversion = up_conversion self.vertices = [] self.colors = [] self.normals = [] self.tex_coords = [] self.parts = [] self.current_part = None self.bounding_box = BoundingBox() self.center_and_scale = True self.path = None def init_textures(self): """Initializes the textures of the parts of the model Basically, calls glGenTexture on each texture """ for part in self.parts: part.init_texture() def add_vertex(self, vertex): """Adds a vertex to the current model Will also update its bounding box, and convert the up vector if up_conversion was specified. :param vertex: vertex to add to the model """ # Apply up_conversion to the vertex new_vertex = vertex if self.up_conversion is not None: if self.up_conversion[0] == 'y' and self.up_conversion[1] == 'z': new_vertex = Vector(vertex.y, vertex.z, vertex.x) elif self.up_conversion[0] == 'z' and self.up_conversion[1] == 'y': new_vertex = Vector(vertex.z, vertex.x, vertex.y) self.vertices.append(new_vertex) self.bounding_box.add(new_vertex) def add_tex_coord(self, tex_coord): """Adds a texture coordinate element to the current model :param tex_coord: tex_coord to add to the model """ self.tex_coords.append(tex_coord) def add_normal(self, normal): """Adds a normal element to the current model :param normal: normal to add to the model """ self.normals.append(normal) def add_color(self, color): """Adds a color element to the current model :param color: color to add to the model """ self.colors.append(color) def add_face(self, face): """Adds a face to the current model If the face has a different material than the current material, it will create a new mesh part and update the current material. :param face: face to add to the model """ if self.current_part is None or (face.material != self.current_part.material and face.material is not None): self.current_part = MeshPart(self) self.current_part.material = face.material if face.material is not None else Material.DEFAULT_MATERIAL self.parts.append(self.current_part) self.current_part.add_face(face) def parse_file(self, path, chunk_size = 512): """Sets the path of the model and parse bytes by chunk :param path: path to the file to parse :param chunk_size: the file will be read chunk by chunk, each chunk having chunk_size bytes """ self.path = path byte_counter = 0 with open(path, 'rb') as f: while True: bytes = f.read(chunk_size) if bytes == b'': return self.parse_bytes(bytes, byte_counter) byte_counter += chunk_size def draw(self): """Draws each part of the model with OpenGL """ import OpenGL.GL as gl if self.center_and_scale: center = self.bounding_box.get_center() scale = self.bounding_box.get_scale() / 2 gl.glPushMatrix() gl.glScalef(1/scale, 1/scale, 1/scale) gl.glTranslatef(-center.x, -center.y, -center.z) for part in self.parts: part.draw() if self.center_and_scale: gl.glPopMatrix() def generate_vbos(self): """Generates the VBOs of each part of the model """ for part in self.parts: part.generate_vbos() def generate_vertex_normals(self): """Generate the normals for each vertex of the model A normal will be the average normal of the adjacent faces of a vertex. """ self.normals = [Normal() for i in self.vertices] for part in self.parts: for face in part.faces: v1 = Vertex.from_points(self.vertices[face.a.vertex], self.vertices[face.b.vertex]) v2 = Vertex.from_points(self.vertices[face.a.vertex], self.vertices[face.c.vertex]) cross = Vertex.cross_product(v1, v2) self.normals[face.a.vertex] += cross self.normals[face.b.vertex] += cross self.normals[face.c.vertex] += cross for normal in self.normals: normal.normalize() for part in self.parts: for face in part.faces: face.a.normal = face.a.vertex face.b.normal = face.b.vertex face.c.normal = face.c.vertex def generate_face_normals(self): """Generate the normals for each face of the model A normal will be the normal of the face """ # Build array of faces faces = sum(map(lambda x: x.faces, self.parts), []) self.normals = [Normal()] * len(faces) for (index, face) in enumerate(faces): v1 = Vertex.from_points(self.vertices[face.a.vertex], self.vertices[face.b.vertex]) v2 = Vertex.from_points(self.vertices[face.a.vertex], self.vertices[face.c.vertex]) cross = Vertex.cross_product(v1, v2) cross.normalize() self.normals[index] = cross face.a.normal = index face.b.normal = index face.c.normal = index class TextModelParser(ModelParser): def parse_file(self, path): """Sets the path of the model and parse each line :param path: path to the text file to parse """ self.path = path with open(path) as f: for line in f.readlines(): line = line.rstrip() if line != '': self.parse_line(line) class BoundingBox: """Represents a bounding box of a 3D model """ def __init__(self): """Initializes the coordinates of the bounding box """ self.min_x = +float('inf') self.min_y = +float('inf') self.min_z = +float('inf') self.max_x = -float('inf') self.max_y = -float('inf') self.max_z = -float('inf') def add(self, vector): """Adds a vector to a bounding box If the vector is outside the bounding box, the bounding box will be enlarged, otherwise, nothing will happen. :param vector: the vector that will enlarge the bounding box """ self.min_x = min(self.min_x, vector.x) self.min_y = min(self.min_y, vector.y) self.min_z = min(self.min_z, vector.z) self.max_x = max(self.max_x, vector.x) self.max_y = max(self.max_y, vector.y) self.max_z = max(self.max_z, vector.z) def __str__(self): """Returns a string that represents the bounding box """ return "[{},{}],[{},{}],[{},{}]".format( self.min_x, self.min_y, self.min_z, self.max_x, self.max_y, self.max_z) def get_center(self): """Returns the center of the bounding box """ return Vertex( (self.min_x + self.max_x) / 2, (self.min_y + self.max_y) / 2, (self.min_z + self.max_z) / 2) def get_scale(self): """Returns the maximum edge of the bounding box """ return max( abs(self.max_x - self.min_x), abs(self.max_y - self.min_y), abs(self.max_z - self.min_z)) class Exporter: """Represents an object that can export a model into a certain format """ def __init__(self, model): """Creates a exporter for the model :param model: model to export """ self.model = model