def get_bbox_transform(boxin, boxout):
"""
return the transform that maps transform one bounding box to
another
"""
return SeparableTransformation(boxin, boxout, Func(IDENTITY),
Func(IDENTITY))
def identity_transform():
"""
Get an affine transformation that maps x,y -> x,y
"""
return SeparableTransformation(unit_bbox(), unit_bbox(),
Func(IDENTITY),
Func(IDENTITY))
def scale_sep_transform(sx, sy):
"""
Return a pure scale transformation as a SeparableTransformation;
sx and sy are LazyValue instances (Values or binary opertations on
values)
"""
bboxin = unit_bbox()
bboxout = Bbox(Point(zero(), zero()), Point(sx, sy))
return SeparableTransformation(bboxin, bboxout, Func(IDENTITY),
Func(IDENTITY))
def identity_funcxy():
"""
Get funcxy instance that maps x,y -> x,y
"""
return FuncXY(Func(IDENTITY), Func(IDENTITY))
