def __init__(self, mesh: MeshInstance, element_type: MeshElementType,
entry_expr: impl.Expr):
self.mesh = mesh
self.element_type = element_type
self.entry_expr = entry_expr
element_field = self.mesh.fields[self.element_type]
for key, attr in element_field.field_dict.items():
global_entry_expr = impl.Expr(
_ti_core.get_index_conversion(
self.mesh.mesh_ptr, element_type, entry_expr,
ConvType.l2r if element_field.attr_dict[key].reorder else
ConvType.l2g)) # transform index space
global_entry_expr_group = impl.make_expr_group(
*tuple([global_entry_expr]))
if isinstance(attr, MatrixField):
setattr(self, key,
_MatrixFieldElement(attr, global_entry_expr_group))
elif isinstance(attr, StructField):
raise RuntimeError('ti.Mesh has not support StructField yet')
else: # isinstance(attr, Field)
var = attr.get_field_members()[0].ptr
setattr(
self, key,
impl.Expr(_ti_core.subscript(var,
global_entry_expr_group)))
for element_type in self.mesh._type.elements:
setattr(self, element_type_name(element_type),
impl.mesh_relation_access(self.mesh, self, element_type))
def subscript(value, *_indices, skip_reordered=False):
if isinstance(value, np.ndarray):
return value.__getitem__(_indices)
if isinstance(value, (tuple, list, dict)):
assert len(_indices) == 1
return value[_indices[0]]
has_slice = False
flattened_indices = []
for _index in _indices:
if is_taichi_class(_index):
ind = _index.entries
elif isinstance(_index, slice):
ind = [_index]
has_slice = True
else:
ind = [_index]
flattened_indices += ind
_indices = tuple(flattened_indices)
if len(_indices) == 1 and _indices[0] is None:
_indices = ()
if has_slice:
if not isinstance(value, Matrix):
raise SyntaxError(
f"The type {type(value)} do not support index of slice type")
else:
indices_expr_group = make_expr_group(*_indices)
index_dim = indices_expr_group.size()
if is_taichi_class(value):
return value._subscript(*_indices)
if isinstance(value, MeshElementFieldProxy):
return value.subscript(*_indices)
if isinstance(value, MeshRelationAccessProxy):
return value.subscript(*_indices)
if isinstance(value,
(MeshReorderedScalarFieldProxy,
MeshReorderedMatrixFieldProxy)) and not skip_reordered:
assert index_dim == 1
reordered_index = tuple([
Expr(
_ti_core.get_index_conversion(value.mesh_ptr,
value.element_type,
Expr(_indices[0]).ptr,
ConvType.g2r))
])
return subscript(value, *reordered_index, skip_reordered=True)
if isinstance(value, SparseMatrixProxy):
return value.subscript(*_indices)
if isinstance(value, Field):
_var = value._get_field_members()[0].ptr
if _var.snode() is None:
if _var.is_primal():
raise RuntimeError(
f"{_var.get_expr_name()} has not been placed.")
else:
raise RuntimeError(
f"Gradient {_var.get_expr_name()} has not been placed, check whether `needs_grad=True`"
)
field_dim = int(_var.get_attribute("dim"))
if field_dim != index_dim:
raise IndexError(
f'Field with dim {field_dim} accessed with indices of dim {index_dim}'
)
if isinstance(value, MatrixField):
return _MatrixFieldElement(value, indices_expr_group)
if isinstance(value, StructField):
return _IntermediateStruct(
{k: subscript(v, *_indices)
for k, v in value._items})
return Expr(_ti_core.subscript(_var, indices_expr_group))
if isinstance(value, AnyArray):
# TODO: deprecate using get_attribute to get dim
field_dim = int(value.ptr.get_attribute("dim"))
element_dim = len(value.element_shape)
if field_dim != index_dim + element_dim:
raise IndexError(
f'Field with dim {field_dim - element_dim} accessed with indices of dim {index_dim}'
)
if element_dim == 0:
return Expr(_ti_core.subscript(value.ptr, indices_expr_group))
n = value.element_shape[0]
m = 1 if element_dim == 1 else value.element_shape[1]
any_array_access = AnyArrayAccess(value, _indices)
ret = _IntermediateMatrix(n, m, [
any_array_access.subscript(i, j) for i in range(n)
for j in range(m)
])
ret.any_array_access = any_array_access
return ret
if isinstance(value, SNode):
# When reading bit structure we only support the 0-D case for now.
field_dim = 0
if field_dim != index_dim:
raise IndexError(
f'Field with dim {field_dim} accessed with indices of dim {index_dim}'
)
return Expr(_ti_core.subscript(value.ptr, indices_expr_group))
# Directly evaluate in Python for non-Taichi types
return value.__getitem__(*_indices)