def get_flags(self):
return vips_lib.vips_operation_get_flags(self.pointer)
def __init__(self, operation_name):
op = Operation.new_from_name(operation_name)
self.description = op.get_description()
self.flags = vips_lib.vips_operation_get_flags(op.pointer)
# build a list of constructor arg [name, flags] pairs in arg order
arguments = []
def add_args(name, flags):
if (flags & _CONSTRUCT) != 0:
# libvips uses '-' to separate parts of arg names, but we
# need '_' for Python
name = name.replace('-', '_')
arguments.append([name, flags])
if at_least_libvips(8, 7):
p_names = ffi.new('char**[1]')
p_flags = ffi.new('int*[1]')
p_n_args = ffi.new('int[1]')
result = vips_lib.vips_object_get_args(op.vobject, p_names,
p_flags, p_n_args)
if result != 0:
raise Error('unable to get arguments from operation')
p_names = p_names[0]
p_flags = p_flags[0]
n_args = p_n_args[0]
for i in range(0, n_args):
add_args(_to_string(p_names[i]), p_flags[i])
else:
def add_construct(self, pspec, argument_class, argument_instance,
a, b):
add_args(_to_string(pspec.name), argument_class.flags)
return ffi.NULL
cb = ffi.callback('VipsArgumentMapFn', add_construct)
vips_lib.vips_argument_map(op.vobject, cb, ffi.NULL, ffi.NULL)
# logger.debug('arguments = %s', self.arguments)
# build a hash from arg name to detailed arg information
self.details = {}
for name, flags in arguments:
self.details[name] = {
"name": name,
"flags": flags,
"blurb": op.get_blurb(name),
"type": op.get_typeof(name)
}
# lists of arg names by category
self.required_input = []
self.optional_input = []
self.required_output = []
self.optional_output = []
for name, flags in arguments:
if ((flags & _INPUT) != 0 and (flags & _REQUIRED) != 0
and (flags & _DEPRECATED) == 0):
self.required_input.append(name)
# required inputs which we MODIFY are also required outputs
if (flags & _MODIFY) != 0:
self.required_output.append(name)
if ((flags & _OUTPUT) != 0 and (flags & _REQUIRED) != 0
and (flags & _DEPRECATED) == 0):
self.required_output.append(name)
# we let deprecated optional args through, but warn about them
# if they get used, see below
if ((flags & _INPUT) != 0 and (flags & _REQUIRED) == 0):
self.optional_input.append(name)
if ((flags & _OUTPUT) != 0 and (flags & _REQUIRED) == 0):
self.optional_output.append(name)
# find the first required input image arg, if any ... that will be self
self.member_x = None
for name in self.required_input:
details = self.details[name]
if details['type'] == GValue.image_type:
self.member_x = name
break
# method args are required args, but without the image they are a
# method on
if self.member_x is not None:
self.method_args = list(self.required_input)
self.method_args.remove(self.member_x)
else:
self.method_args = self.required_input