def __init__(self, filename):
obj = OBJ(filename)
# The number of materials should be one
assert len(obj.mfaces) is 1
material, tfaces = obj.mfaces[0]
# The number of meshes should be one
assert len(tfaces) is 1
desc, faces = tfaces[0]
# The number of faces should be three
assert desc[0] is 3
# Decouple tuples
vertices = []
for v in obj.vertices:
vertices.extend(v)
# Note that face/quads/polys indices in Wavefront OBJ
# starts from 1 and therefore must be decremented in order
# to properly work with Bullet
indices = [i-1 for i in faces[0]]
# Build numpy arrays
self.vertices = array(vertices, 'f')
self.indices = array(indices, 'i')
# Create mesh
self.mesh = IndexedMesh()
self.mesh.setVertices(self.vertices.size / 3, 3 * self.vertices.itemsize, self.vertices)
self.mesh.setIndices(self.indices.size / 3, 3 * self.indices.itemsize, self.indices)
def __init__(self):
# Vertices are coordinates in three-space. These four will define two
# triangles, with two vertices shared between them.
self.groundVertices = array([
0, 0, 0,
10, 0, 0,
10, 0, 10,
0, 0, 10], 'f')
# These indices are used to find vertices in the groundVertices array.
# They index a vertex, not an individual float. So a value of 1 refers
# to the 2nd triple in groundVertices (ie 10, 0, 0). Three indices
# define one triangle, so this array defines two triangles.
self.groundIndices = array(
[0, 1, 2,
2, 3, 0],
'i')
# Create a single triangle mesh to use as part of the array of triangle
# meshes that will define the shape of the ground object.
groundMesh = IndexedMesh()
# Set the indices of this mesh. Specify the number of triangles it
# will define (2), the stride in bytes between the beginning of index
# triples, and the array actually containing the data. Since this
# index data is tightly packed, the stride is just the size of a single
# index times the number of indices per triangle (3).
groundMesh.setIndices(
2, 3 * self.groundIndices.itemsize, self.groundIndices)
# Set the vertex data of this mesh. Specify the number of vertices it
# will define (4), the stride in bytes between the beginning of vertex
# triples, and the array actually containing the data. Since the
# vertex data is tightly packed, the stride is just the size of a
# single vertex component (ie x, y, or z value) times the number of
# components per vertex (3).
groundMesh.setVertices(
4, 3 * self.groundVertices.itemsize, self.groundVertices)
# Create a container for the single IndexedMesh, but we could add more
# to this if we had any.
groundStuff = TriangleIndexVertexArray()
groundStuff.addIndexedMesh(groundMesh)
# Create a shape based on that array of IndexedMesh instances.
groundShape = BvhTriangleMeshShape(groundStuff)
# Since the data is completely specified at this point, tell the shape
# to build its optimized internal data structure. XXX This is somewhat
# bad, and forgetting to do it will cause problems like segfaults. It
# would be nice if it were not required.
groundShape.buildOptimizedBvh()
# Position the ground at an offset so that it's actually centered at
# the origin (we could also have used -5s and 5s in the vertex data,
# instead of 0s and 10s).
groundTransform = Transform()
groundTransform.setIdentity()
groundTransform.setOrigin(Vector3(-5, -5, -5))
# Install a motion state object which we can inspect later to find out
# if the ground has moved (it won't, though).
groundMotion = DefaultMotionState()
groundMotion.setWorldTransform(groundTransform)
# Create the actual collision object using the motion state and the
# shape.
self.body = RigidBody(groundMotion, groundShape)
self.motion = groundMotion
def __init__(self):
# Vertices are coordinates in three-space. These four will define two
# triangles, with two vertices shared between them.
self.groundVertices = array([0, 0, 0, 10, 0, 0, 10, 0, 10, 0, 0, 10],
'f')
# These indices are used to find vertices in the groundVertices array.
# They index a vertex, not an individual float. So a value of 1 refers
# to the 2nd triple in groundVertices (ie 10, 0, 0). Three indices
# define one triangle, so this array defines two triangles.
self.groundIndices = array([0, 1, 2, 2, 3, 0], 'i')
# Create a single triangle mesh to use as part of the array of triangle
# meshes that will define the shape of the ground object.
groundMesh = IndexedMesh()
# Set the indices of this mesh. Specify the number of triangles it
# will define (2), the stride in bytes between the beginning of index
# triples, and the array actually containing the data. Since this
# index data is tightly packed, the stride is just the size of a single
# index times the number of indices per triangle (3).
groundMesh.setIndices(2, 3 * self.groundIndices.itemsize,
self.groundIndices)
# Set the vertex data of this mesh. Specify the number of vertices it
# will define (4), the stride in bytes between the beginning of vertex
# triples, and the array actually containing the data. Since the
# vertex data is tightly packed, the stride is just the size of a
# single vertex component (ie x, y, or z value) times the number of
# components per vertex (3).
groundMesh.setVertices(4, 3 * self.groundVertices.itemsize,
self.groundVertices)
# Create a container for the single IndexedMesh, but we could add more
# to this if we had any.
groundStuff = TriangleIndexVertexArray()
groundStuff.addIndexedMesh(groundMesh)
# Create a shape based on that array of IndexedMesh instances.
groundShape = BvhTriangleMeshShape(groundStuff)
# Since the data is completely specified at this point, tell the shape
# to build its optimized internal data structure. XXX This is somewhat
# bad, and forgetting to do it will cause problems like segfaults. It
# would be nice if it were not required.
groundShape.buildOptimizedBvh()
# Position the ground at an offset so that it's actually centered at
# the origin (we could also have used -5s and 5s in the vertex data,
# instead of 0s and 10s).
groundTransform = Transform()
groundTransform.setIdentity()
groundTransform.setOrigin(Vector3(-5, -5, -5))
# Install a motion state object which we can inspect later to find out
# if the ground has moved (it won't, though).
groundMotion = DefaultMotionState()
groundMotion.setWorldTransform(groundTransform)
# Create the actual collision object using the motion state and the
# shape.
self.body = RigidBody(groundMotion, groundShape)
self.motion = groundMotion
