from math import sqrt from ..geometry import Vector from .mesh import Material, MeshPart Vertex = Vector Normal = Vertex TexCoord = 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. """ def __init__(self, vertex = None, tex_coord = None, normal = None): """Initializes a FaceVertex from its indices """ self.vertex = vertex self.tex_coord = tex_coord self.normal = normal def from_array(self, arr): """Initializes a FaceVertex from an array The array can be an array of strings, the first value will be the vertex index, the second will be the texture coordinate index, and the third will be the normal 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 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 """ 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 The array 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 """ self.up_conversion = up_conversion self.vertices = [] self.normals = [] self.tex_coords = [] self.parts = [] self.current_part = None self.bounding_box = BoundingBox() self.center_and_scale = True self.vertex_vbo = None self.tex_coord_vbo = None self.normal_vbo = None 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. """ # 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 """ self.tex_coords.append(tex_coord) def add_normal(self, normal): """Adds a normal element to the current model """ self.normals.append(normal) 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. """ 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 """ 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 """ 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. """ 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): self.model = model