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import os
import tensorflow as tf
import diffvg
import pydiffvg_tensorflow as pydiffvg
import time
from enum import IntEnum
import warnings
print_timing = False
__EMPTY_TENSOR = tf.constant([])
def is_empty_tensor(tensor):
return tf.equal(tf.size(tensor), 0)
def set_print_timing(val):
global print_timing
print_timing=val
class OutputType(IntEnum):
color = 1
sdf = 2
class ShapeType:
__shapetypes = [
diffvg.ShapeType.circle,
diffvg.ShapeType.ellipse,
diffvg.ShapeType.path,
diffvg.ShapeType.rect
]
@staticmethod
def asTensor(type):
for i in range(len(ShapeType.__shapetypes)):
if ShapeType.__shapetypes[i] == type:
return tf.constant(i)
@staticmethod
def asShapeType(index: tf.Tensor):
if is_empty_tensor(index):
return None
try:
type = ShapeType.__shapetypes[index]
except IndexError:
print(f'{index} is out of range: [0, {len(ShapeType.__shapetypes)})')
import sys
sys.exit()
else:
return type
class ColorType:
__colortypes = [
diffvg.ColorType.constant,
diffvg.ColorType.linear_gradient,
diffvg.ColorType.radial_gradient
]
@staticmethod
def asTensor(type):
for i in range(len(ColorType.__colortypes)):
if ColorType.__colortypes[i] == type:
return tf.constant(i)
@staticmethod
def asColorType(index: tf.Tensor):
if is_empty_tensor(index):
return None
try:
type = ColorType.__colortypes[index]
except IndexError:
print(f'{index} is out of range: [0, {len(ColorType.__colortypes)})')
import sys
sys.exit()
else:
return type
class FilterType:
__filtertypes = [
diffvg.FilterType.box,
diffvg.FilterType.tent,
diffvg.FilterType.hann
]
@staticmethod
def asTensor(type):
for i in range(len(FilterType.__filtertypes)):
if FilterType.__filtertypes[i] == type:
return tf.constant(i)
@staticmethod
def asFilterType(index: tf.Tensor):
if is_empty_tensor(index):
return None
try:
type = FilterType.__filtertypes[index]
except IndexError:
print(f'{index} is out of range: [0, {len(FilterType.__filtertypes)})')
import sys
sys.exit()
else:
return type
def serialize_scene(canvas_width,
canvas_height,
shapes,
shape_groups,
filter = pydiffvg.PixelFilter(type = diffvg.FilterType.box,
radius = tf.constant(0.5)),
output_type = OutputType.color,
use_prefiltering = False):
"""
Given a list of shapes, convert them to a linear list of argument,
so that we can use it in TF.
"""
with tf.device('/device:cpu:' + str(pydiffvg.get_cpu_device_id())):
num_shapes = len(shapes)
num_shape_groups = len(shape_groups)
args = []
args.append(tf.constant(canvas_width))
args.append(tf.constant(canvas_height))
args.append(tf.constant(num_shapes))
args.append(tf.constant(num_shape_groups))
args.append(tf.constant(output_type))
args.append(tf.constant(use_prefiltering))
for shape in shapes:
if isinstance(shape, pydiffvg.Circle):
args.append(ShapeType.asTensor(diffvg.ShapeType.circle))
args.append(tf.identity(shape.radius))
args.append(tf.identity(shape.center))
elif isinstance(shape, pydiffvg.Ellipse):
args.append(ShapeType.asTensor(diffvg.ShapeType.ellipse))
args.append(tf.identity(shape.radius))
args.append(tf.identity(shape.center))
elif isinstance(shape, pydiffvg.Path):
assert(shape.points.shape[1] == 2)
args.append(ShapeType.asTensor(diffvg.ShapeType.path))
args.append(tf.identity(shape.num_control_points))
args.append(tf.identity(shape.points))
args.append(tf.constant(shape.is_closed))
args.append(tf.constant(shape.use_distance_approx))
elif isinstance(shape, pydiffvg.Polygon):
assert(shape.points.shape[1] == 2)
args.append(ShapeType.asTensor(diffvg.ShapeType.path))
if shape.is_closed:
args.append(tf.zeros(shape.points.shape[0], dtype = tf.int32))
else:
args.append(tf.zeros(shape.points.shape[0] - 1, dtype = tf.int32))
args.append(tf.identity(shape.points))
args.append(tf.constant(shape.is_closed))
elif isinstance(shape, pydiffvg.Rect):
args.append(ShapeType.asTensor(diffvg.ShapeType.rect))
args.append(tf.identity(shape.p_min))
args.append(tf.identity(shape.p_max))
else:
assert(False)
args.append(tf.identity(shape.stroke_width))
for shape_group in shape_groups:
args.append(tf.identity(shape_group.shape_ids))
# Fill color
if shape_group.fill_color is None:
args.append(__EMPTY_TENSOR)
elif tf.is_tensor(shape_group.fill_color):
args.append(ColorType.asTensor(diffvg.ColorType.constant))
args.append(tf.identity(shape_group.fill_color))
elif isinstance(shape_group.fill_color, pydiffvg.LinearGradient):
args.append(ColorType.asTensor(diffvg.ColorType.linear_gradient))
args.append(tf.identity(shape_group.fill_color.begin))
args.append(tf.identity(shape_group.fill_color.end))
args.append(tf.identity(shape_group.fill_color.offsets))
args.append(tf.identity(shape_group.fill_color.stop_colors))
elif isinstance(shape_group.fill_color, pydiffvg.RadialGradient):
args.append(ColorType.asTensor(diffvg.ColorType.radial_gradient))
args.append(tf.identity(shape_group.fill_color.center))
args.append(tf.identity(shape_group.fill_color.radius))
args.append(tf.identity(shape_group.fill_color.offsets))
args.append(tf.identity(shape_group.fill_color.stop_colors))
if shape_group.fill_color is not None:
# go through the underlying shapes and check if they are all closed
for shape_id in shape_group.shape_ids:
if isinstance(shapes[shape_id], pydiffvg.Path):
if not shapes[shape_id].is_closed:
warnings.warn("Detected non-closed paths with fill color. This might causes unexpected results.", Warning)
# Stroke color
if shape_group.stroke_color is None:
args.append(__EMPTY_TENSOR)
elif tf.is_tensor(shape_group.stroke_color):
args.append(tf.constant(0))
args.append(tf.identity(shape_group.stroke_color))
elif isinstance(shape_group.stroke_color, pydiffvg.LinearGradient):
args.append(ColorType.asTensor(diffvg.ColorType.linear_gradient))
args.append(tf.identity(shape_group.stroke_color.begin))
args.append(tf.identity(shape_group.stroke_color.end))
args.append(tf.identity(shape_group.stroke_color.offsets))
args.append(tf.identity(shape_group.stroke_color.stop_colors))
elif isinstance(shape_group.stroke_color, pydiffvg.RadialGradient):
args.append(ColorType.asTensor(diffvg.ColorType.radial_gradient))
args.append(tf.identity(shape_group.stroke_color.center))
args.append(tf.identity(shape_group.stroke_color.radius))
args.append(tf.identity(shape_group.stroke_color.offsets))
args.append(tf.identity(shape_group.stroke_color.stop_colors))
args.append(tf.constant(shape_group.use_even_odd_rule))
# Transformation
args.append(tf.identity(shape_group.shape_to_canvas))
args.append(FilterType.asTensor(filter.type))
args.append(tf.constant(filter.radius))
return args
class Context: pass
def forward(width,
height,
num_samples_x,
num_samples_y,
seed,
*args):
"""
Forward rendering pass: given a serialized scene and output an image.
"""
# Unpack arguments
with tf.device('/device:cpu:' + str(pydiffvg.get_cpu_device_id())):
current_index = 0
canvas_width = int(args[current_index])
current_index += 1
canvas_height = int(args[current_index])
current_index += 1
num_shapes = int(args[current_index])
current_index += 1
num_shape_groups = int(args[current_index])
current_index += 1
output_type = OutputType(int(args[current_index]))
current_index += 1
use_prefiltering = bool(args[current_index])
current_index += 1
shapes = []
shape_groups = []
shape_contents = [] # Important to avoid GC deleting the shapes
color_contents = [] # Same as above
for shape_id in range(num_shapes):
shape_type = ShapeType.asShapeType(args[current_index])
current_index += 1
if shape_type == diffvg.ShapeType.circle:
radius = args[current_index]
current_index += 1
center = args[current_index]
current_index += 1
shape = diffvg.Circle(float(radius),
diffvg.Vector2f(float(center[0]), float(center[1])))
elif shape_type == diffvg.ShapeType.ellipse:
radius = args[current_index]
current_index += 1
center = args[current_index]
current_index += 1
shape = diffvg.Ellipse(diffvg.Vector2f(float(radius[0]), float(radius[1])),
diffvg.Vector2f(float(center[0]), float(center[1])))
elif shape_type == diffvg.ShapeType.path:
num_control_points = args[current_index]
current_index += 1
points = args[current_index]
current_index += 1
is_closed = args[current_index]
current_index += 1
use_distance_approx = args[current_index]
current_index += 1
shape = diffvg.Path(diffvg.int_ptr(pydiffvg.data_ptr(num_control_points)),
diffvg.float_ptr(pydiffvg.data_ptr(points)),
diffvg.float_ptr(0), # thickness
num_control_points.shape[0],
points.shape[0],
is_closed,
use_distance_approx)
elif shape_type == diffvg.ShapeType.rect:
p_min = args[current_index]
current_index += 1
p_max = args[current_index]
current_index += 1
shape = diffvg.Rect(diffvg.Vector2f(float(p_min[0]), float(p_min[1])),
diffvg.Vector2f(float(p_max[0]), float(p_max[1])))
else:
assert(False)
stroke_width = args[current_index]
current_index += 1
shapes.append(diffvg.Shape(\
shape_type, shape.get_ptr(), float(stroke_width)))
shape_contents.append(shape)
for shape_group_id in range(num_shape_groups):
shape_ids = args[current_index]
current_index += 1
fill_color_type = ColorType.asColorType(args[current_index])
current_index += 1
if fill_color_type == diffvg.ColorType.constant:
color = args[current_index]
current_index += 1
fill_color = diffvg.Constant(\
diffvg.Vector4f(color[0], color[1], color[2], color[3]))
elif fill_color_type == diffvg.ColorType.linear_gradient:
beg = args[current_index]
current_index += 1
end = args[current_index]
current_index += 1
offsets = args[current_index]
current_index += 1
stop_colors = args[current_index]
current_index += 1
assert(offsets.shape[0] == stop_colors.shape[0])
fill_color = diffvg.LinearGradient(diffvg.Vector2f(float(beg[0]), float(beg[1])),
diffvg.Vector2f(float(end[0]), float(end[1])),
offsets.shape[0],
diffvg.float_ptr(pydiffvg.data_ptr(offsets)),
diffvg.float_ptr(pydiffvg.data_ptr(stop_colors)))
elif fill_color_type == diffvg.ColorType.radial_gradient:
center = args[current_index]
current_index += 1
radius = args[current_index]
current_index += 1
offsets = args[current_index]
current_index += 1
stop_colors = args[current_index]
current_index += 1
assert(offsets.shape[0] == stop_colors.shape[0])
fill_color = diffvg.RadialGradient(diffvg.Vector2f(float(center[0]), float(center[1])),
diffvg.Vector2f(float(radius[0]), float(radius[1])),
offsets.shape[0],
diffvg.float_ptr(pydiffvg.data_ptr(offsets)),
diffvg.float_ptr(pydiffvg.data_ptr(stop_colors)))
elif fill_color_type is None:
fill_color = None
else:
assert(False)
stroke_color_type = ColorType.asColorType(args[current_index])
current_index += 1
if stroke_color_type == diffvg.ColorType.constant:
color = args[current_index]
current_index += 1
stroke_color = diffvg.Constant(\
diffvg.Vector4f(float(color[0]),
float(color[1]),
float(color[2]),
float(color[3])))
elif stroke_color_type == diffvg.ColorType.linear_gradient:
beg = args[current_index]
current_index += 1
end = args[current_index]
current_index += 1
offsets = args[current_index]
current_index += 1
stop_colors = args[current_index]
current_index += 1
assert(offsets.shape[0] == stop_colors.shape[0])
stroke_color = diffvg.LinearGradient(\
diffvg.Vector2f(float(beg[0]), float(beg[1])),
diffvg.Vector2f(float(end[0]), float(end[1])),
offsets.shape[0],
diffvg.float_ptr(pydiffvg.data_ptr(offsets)),
diffvg.float_ptr(stop_colors.data_ptr()))
elif stroke_color_type == diffvg.ColorType.radial_gradient:
center = args[current_index]
current_index += 1
radius = args[current_index]
current_index += 1
offsets = args[current_index]
current_index += 1
stop_colors = args[current_index]
current_index += 1
assert(offsets.shape[0] == stop_colors.shape[0])
stroke_color = diffvg.RadialGradient(\
diffvg.Vector2f(float(center[0]), float(center[1])),
diffvg.Vector2f(float(radius[0]), float(radius[1])),
offsets.shape[0],
diffvg.float_ptr(pydiffvg.data_ptr(offsets)),
diffvg.float_ptr(pydiffvg.data_ptr(stop_colors)))
elif stroke_color_type is None:
stroke_color = None
else:
assert(False)
use_even_odd_rule = bool(args[current_index])
current_index += 1
shape_to_canvas = args[current_index]
current_index += 1
if fill_color is not None:
color_contents.append(fill_color)
if stroke_color is not None:
color_contents.append(stroke_color)
shape_groups.append(diffvg.ShapeGroup(\
diffvg.int_ptr(pydiffvg.data_ptr(shape_ids)),
shape_ids.shape[0],
diffvg.ColorType.constant if fill_color_type is None else fill_color_type,
diffvg.void_ptr(0) if fill_color is None else fill_color.get_ptr(),
diffvg.ColorType.constant if stroke_color_type is None else stroke_color_type,
diffvg.void_ptr(0) if stroke_color is None else stroke_color.get_ptr(),
use_even_odd_rule,
diffvg.float_ptr(pydiffvg.data_ptr(shape_to_canvas))))
filter_type = FilterType.asFilterType(args[current_index])
current_index += 1
filter_radius = args[current_index]
current_index += 1
filt = diffvg.Filter(filter_type, filter_radius)
device_name = pydiffvg.get_device_name()
device_spec = tf.DeviceSpec.from_string(device_name)
use_gpu = device_spec.device_type == 'GPU'
gpu_index = device_spec.device_index if device_spec.device_index is not None else 0
start = time.time()
scene = diffvg.Scene(canvas_width,
canvas_height,
shapes,
shape_groups,
filt,
use_gpu,
gpu_index)
time_elapsed = time.time() - start
global print_timing
if print_timing:
print('Scene construction, time: %.5f s' % time_elapsed)
with tf.device(device_name):
if output_type == OutputType.color:
rendered_image = tf.zeros((int(height), int(width), 4), dtype = tf.float32)
else:
assert(output_type == OutputType.sdf)
rendered_image = tf.zeros((int(height), int(width), 1), dtype = tf.float32)
start = time.time()
diffvg.render(scene,
diffvg.float_ptr(0), # background image
diffvg.float_ptr(pydiffvg.data_ptr(rendered_image) if output_type == OutputType.color else 0),
diffvg.float_ptr(pydiffvg.data_ptr(rendered_image) if output_type == OutputType.sdf else 0),
width,
height,
int(num_samples_x),
int(num_samples_y),
seed,
diffvg.float_ptr(0), # d_background_image
diffvg.float_ptr(0), # d_render_image
diffvg.float_ptr(0), # d_render_sdf
diffvg.float_ptr(0), # d_translation
use_prefiltering,
diffvg.float_ptr(0), # eval_positions
0 ) # num_eval_positions (automatically set to entire raster)
time_elapsed = time.time() - start
if print_timing:
print('Forward pass, time: %.5f s' % time_elapsed)
ctx = Context()
ctx.scene = scene
ctx.shape_contents = shape_contents
ctx.color_contents = color_contents
ctx.filter = filt
ctx.width = width
ctx.height = height
ctx.num_samples_x = num_samples_x
ctx.num_samples_y = num_samples_y
ctx.seed = seed
ctx.output_type = output_type
ctx.use_prefiltering = use_prefiltering
return rendered_image, ctx
@tf.custom_gradient
def render(*x):
"""
The main TensorFlow interface of C++ diffvg.
"""
assert(tf.executing_eagerly())
if pydiffvg.get_use_gpu() and os.environ.get('TF_FORCE_GPU_ALLOW_GROWTH') != 'true':
print('******************** WARNING ********************')
print('Tensorflow by default allocates all GPU memory,')
print('causing huge amount of page faults when rendering.')
print('Please set the environment variable TF_FORCE_GPU_ALLOW_GROWTH to true,')
print('so that Tensorflow allocates memory on demand.')
print('*************************************************')
width = x[0]
height = x[1]
num_samples_x = x[2]
num_samples_y = x[3]
seed = x[4]
args = x[5:]
img, ctx = forward(width, height, num_samples_x, num_samples_y, seed, *args)
def backward(grad_img):
scene = ctx.scene
width = ctx.width
height = ctx.height
num_samples_x = ctx.num_samples_x
num_samples_y = ctx.num_samples_y
seed = ctx.seed
output_type = ctx.output_type
use_prefiltering = ctx.use_prefiltering
start = time.time()
with tf.device(pydiffvg.get_device_name()):
diffvg.render(scene,
diffvg.float_ptr(0), # background_image
diffvg.float_ptr(0), # render_image
diffvg.float_ptr(0), # render_sdf
width,
height,
num_samples_x,
num_samples_y,
seed,
diffvg.float_ptr(0), # d_background_image
diffvg.float_ptr(pydiffvg.data_ptr(grad_img) if output_type == OutputType.color else 0),
diffvg.float_ptr(pydiffvg.data_ptr(grad_img) if output_type == OutputType.sdf else 0),
diffvg.float_ptr(0), # d_translation
use_prefiltering,
diffvg.float_ptr(0), # eval_positions
0 ) # num_eval_positions (automatically set to entire raster))
time_elapsed = time.time() - start
global print_timing
if print_timing:
print('Backward pass, time: %.5f s' % time_elapsed)
with tf.device('/device:cpu:' + str(pydiffvg.get_cpu_device_id())):
d_args = []
d_args.append(None) # width
d_args.append(None) # height
d_args.append(None) # num_samples_x
d_args.append(None) # num_samples_y
d_args.append(None) # seed
d_args.append(None) # canvas_width
d_args.append(None) # canvas_height
d_args.append(None) # num_shapes
d_args.append(None) # num_shape_groups
d_args.append(None) # output_type
d_args.append(None) # use_prefiltering
for shape_id in range(scene.num_shapes):
d_args.append(None) # type
d_shape = scene.get_d_shape(shape_id)
if d_shape.type == diffvg.ShapeType.circle:
d_circle = d_shape.as_circle()
radius = tf.constant(d_circle.radius)
d_args.append(radius)
c = d_circle.center
c = tf.constant((c.x, c.y))
d_args.append(c)
elif d_shape.type == diffvg.ShapeType.ellipse:
d_ellipse = d_shape.as_ellipse()
r = d_ellipse.radius
r = tf.constant((d_ellipse.radius.x, d_ellipse.radius.y))
d_args.append(r)
c = d_ellipse.center
c = tf.constant((c.x, c.y))
d_args.append(c)
elif d_shape.type == diffvg.ShapeType.path:
d_path = d_shape.as_path()
points = tf.zeros((d_path.num_points, 2), dtype=tf.float32)
d_path.copy_to(diffvg.float_ptr(pydiffvg.data_ptr(points)),diffvg.float_ptr(0))
d_args.append(None) # num_control_points
d_args.append(points)
d_args.append(None) # is_closed
d_args.append(None) # use_distance_approx
elif d_shape.type == diffvg.ShapeType.rect:
d_rect = d_shape.as_rect()
p_min = tf.constant((d_rect.p_min.x, d_rect.p_min.y))
p_max = tf.constant((d_rect.p_max.x, d_rect.p_max.y))
d_args.append(p_min)
d_args.append(p_max)
else:
assert(False)
w = tf.constant((d_shape.stroke_width))
d_args.append(w)
for group_id in range(scene.num_shape_groups):
d_shape_group = scene.get_d_shape_group(group_id)
d_args.append(None) # shape_ids
d_args.append(None) # fill_color_type
if d_shape_group.has_fill_color():
if d_shape_group.fill_color_type == diffvg.ColorType.constant:
d_constant = d_shape_group.fill_color_as_constant()
c = d_constant.color
d_args.append(tf.constant((c.x, c.y, c.z, c.w)))
elif d_shape_group.fill_color_type == diffvg.ColorType.linear_gradient:
d_linear_gradient = d_shape_group.fill_color_as_linear_gradient()
beg = d_linear_gradient.begin
d_args.append(tf.constant((beg.x, beg.y)))
end = d_linear_gradient.end
d_args.append(tf.constant((end.x, end.y)))
offsets = tf.zeros((d_linear_gradient.num_stops), dtype=tf.float32)
stop_colors = tf.zeros((d_linear_gradient.num_stops, 4), dtype=tf.float32)
# HACK: tensorflow's eager mode uses a cache to store scalar
# constants to avoid memory copy. If we pass scalar tensors
# into the C++ code and modify them, we would corrupt the
# cache, causing incorrect result in future scalar constant
# creations. Thus we force tensorflow to copy by plusing a zero.
# (also see https://github.com/tensorflow/tensorflow/issues/11186
# for more discussion regarding copying tensors)
if offsets.shape.num_elements() == 1:
offsets = offsets + 0
d_linear_gradient.copy_to(\
diffvg.float_ptr(pydiffvg.data_ptr(offsets)),
diffvg.float_ptr(pydiffvg.data_ptr(stop_colors)))
d_args.append(offsets)
d_args.append(stop_colors)
elif d_shape_group.fill_color_type == diffvg.ColorType.radial_gradient:
d_radial_gradient = d_shape_group.fill_color_as_radial_gradient()
center = d_radial_gradient.center
d_args.append(tf.constant((center.x, center.y)))
radius = d_radial_gradient.radius
d_args.append(tf.constant((radius.x, radius.y)))
offsets = tf.zeros((d_radial_gradient.num_stops))
if offsets.shape.num_elements() == 1:
offsets = offsets + 0
stop_colors = tf.zeros((d_radial_gradient.num_stops, 4))
d_radial_gradient.copy_to(\
diffvg.float_ptr(pydiffvg.data_ptr(offsets)),
diffvg.float_ptr(pydiffvg.data_ptr(stop_colors)))
d_args.append(offsets)
d_args.append(stop_colors)
else:
assert(False)
d_args.append(None) # stroke_color_type
if d_shape_group.has_stroke_color():
if d_shape_group.stroke_color_type == diffvg.ColorType.constant:
d_constant = d_shape_group.stroke_color_as_constant()
c = d_constant.color
d_args.append(tf.constant((c.x, c.y, c.z, c.w)))
elif d_shape_group.stroke_color_type == diffvg.ColorType.linear_gradient:
d_linear_gradient = d_shape_group.stroke_color_as_linear_gradient()
beg = d_linear_gradient.begin
d_args.append(tf.constant((beg.x, beg.y)))
end = d_linear_gradient.end
d_args.append(tf.constant((end.x, end.y)))
offsets = tf.zeros((d_linear_gradient.num_stops))
stop_colors = tf.zeros((d_linear_gradient.num_stops, 4))
if offsets.shape.num_elements() == 1:
offsets = offsets + 0
d_linear_gradient.copy_to(\
diffvg.float_ptr(pydiffvg.data_ptr(offsets)),
diffvg.float_ptr(pydiffvg.data_ptr(stop_colors)))
d_args.append(offsets)
d_args.append(stop_colors)
elif d_shape_group.fill_color_type == diffvg.ColorType.radial_gradient:
d_radial_gradient = d_shape_group.stroke_color_as_radial_gradient()
center = d_radial_gradient.center
d_args.append(tf.constant((center.x, center.y)))
radius = d_radial_gradient.radius
d_args.append(tf.constant((radius.x, radius.y)))
offsets = tf.zeros((d_radial_gradient.num_stops))
stop_colors = tf.zeros((d_radial_gradient.num_stops, 4))
if offsets.shape.num_elements() == 1:
offsets = offsets + 0
d_radial_gradient.copy_to(\
diffvg.float_ptr(pydiffvg.data_ptr(offsets)),
diffvg.float_ptr(pydiffvg.data_ptr(stop_colors)))
d_args.append(offsets)
d_args.append(stop_colors)
else:
assert(False)
d_args.append(None) # use_even_odd_rule
d_shape_to_canvas = tf.zeros((3, 3), dtype = tf.float32)
d_shape_group.copy_to(diffvg.float_ptr(pydiffvg.data_ptr(d_shape_to_canvas)))
d_args.append(d_shape_to_canvas)
d_args.append(None) # filter_type
d_args.append(tf.constant(scene.get_d_filter_radius()))
return d_args
return img, backward