Rect¶
Rect
represents a rectangle defined by four floating point numbers x0, y0, x1, y1. They are viewed as being coordinates of two diagonally opposite points. The first two numbers are regarded as the “top left” corner Px0,y0 and Px1,y1 as the “bottom right” one. However, these two properties need not coincide with their intuitive meanings – read on.
The following remarks are also valid for IRect objects:
Rectangle borders are always parallel to the respective X- and Y-axes.
The constructing points can be anywhere in the plane – they need not even be different, and e.g. “top left” need not be the geometrical “north-western” point.
For any given quadruple of numbers, the geometrically “same” rectangle can be defined in (up to) four different ways: Rect(Px0,y0, Px1,y1), Rect(Px1,y1, Px0,y0), Rect(Px0,y1, Px1,y0), and Rect(Px1,y0, Px0,y1).
Hence some useful classification:
A rectangle is called finite if
x0 <= x1
andy0 <= y1
(i.e. the bottom right point is “south-eastern” to the top left one), otherwise infinite. Of the four alternatives above, only one is finite (disregarding degenerate cases).A rectangle is called empty if
x0 = x1
ory0 = y1
, i.e. if its area is zero.
Note
It sounds like a paradox: a rectangle can be both, infinite and empty …
Methods / Attributes |
Short Description |
---|---|
checks containment of another object |
|
calculate rectangle area |
|
calculate rectangle area |
|
enlarge rectangle to also contain a point |
|
enlarge rectangle to also contain another one |
|
common part with another rectangle |
|
checks for non-empty intersections |
|
makes a rectangle finite |
|
create smallest IRect containing rectangle |
|
transform rectangle with a matrix |
|
bottom left point, synonym |
|
bottom right point, synonym |
|
rectangle height |
|
equals result of method |
|
whether rectangle is empty |
|
whether rectangle is infinite |
|
top left point, synonym |
|
top_right point, synonym |
|
Quad made from rectangle corners |
|
rectangle width |
|
top left corner’s X-coordinate |
|
bottom right corner’s X-coordinate |
|
top left corner’s Y-coordinate |
|
bottom right corner’s Y-coordinate |
Class API
-
class
Rect
¶ -
__init__
(self)¶
-
__init__
(self, x0, y0, x1, y1)
-
__init__
(self, top_left, bottom_right)
-
__init__
(self, top_left, x1, y1)
-
__init__
(self, x0, y0, bottom_right)
-
__init__
(self, rect)
-
__init__
(self, sequence) Overloaded constructors:
top_left
,bottom_right
stand for Point objects, “sequence” is a Python sequence type with 4 float values (see Using Python Sequences as Arguments in PyMuPDF), “rect” means another rectangle, while the other parameters mean float coordinates.If “rect” is specified, the constructor creates a new copy of it.
Without parameters, the rectangle
Rect(0.0, 0.0, 0.0, 0.0)
is created.
-
round
()¶ Creates the smallest containing IRect (this is not the same as simply rounding the rectangle’s edges!).
If the rectangle is infinite, the “normalized” (finite) version of it will be taken. The result of this method is always a finite
IRect
.If the rectangle is empty, the result is also empty.
Possible paradox: The result may be empty, even if the rectangle is not empty! In such cases, the result obviously does not contain the rectangle. This is because MuPDF’s algorithm allows for a small tolerance (1e-3). Example:
>>> r = fitz.Rect(100, 100, 200, 100.001) >>> r.isEmpty False >>> r.round() fitz.IRect(100, 100, 200, 100) >>> r.round().isEmpty True
To reproduce this funny effect on your platform, you may need to adjust the numbers a little after the decimal point.
- Return type
-
transform
(m)¶ Transforms the rectangle with a matrix and replaces the original. If the rectangle is empty or infinite, this is a no-operation.
- Parameters
m (Matrix) – The matrix for the transformation.
- Return type
Rect
- Returns
the smallest rectangle that contains the transformed original.
-
intersect
(r)¶ The intersection (common rectangular area) of the current rectangle and
r
is calculated and replaces the current rectangle. If either rectangle is empty, the result is also empty. Ifr
is infinite, this is a no-operation.- Parameters
r (Rect) – Second rectangle
-
includeRect
(r)¶ The smallest rectangle containing the current one and
r
is calculated and replaces the current one. If either rectangle is infinite, the result is also infinite. If one is empty, the other one will be taken as the result.- Parameters
r (Rect) – Second rectangle
-
includePoint
(p)¶ The smallest rectangle containing the current one and point
p
is calculated and replaces the current one. Infinite rectangles remain unchanged. To create a rectangle containing a series of points, start with (the empty)fitz.Rect(p1, p1)
and successively performincludePoint
operations for the other points.- Parameters
p (Point) – Point to include.
-
getRectArea
([unit])¶
-
getArea
([unit])¶ Calculate the area of the rectangle and, with no parameter, equals
abs(rect)
. Like an empty rectangle, the area of an infinite rectangle is also zero. So, at least one offitz.Rect(p1, p2)
andfitz.Rect(p2, p1)
has a zero area.- Parameters
unit (str) – Specify required unit: respective squares of
px
(pixels, default),in
(inches),cm
(centimeters), ormm
(millimeters).- Return type
float
-
contains
(x)¶ Checks whether
x
is contained in the rectangle. It may be anIRect
,Rect
,Point
or number. Ifx
is an empty rectangle, this is always true. If the rectangle is empty this is alwaysFalse
for all non-empty rectangles and for all points. Ifx
is a number, it will be checked against the four components.x in rect
andrect.contains(x)
are equivalent.
-
intersects
(r)¶ Checks whether the rectangle and
r
(aRect
or IRect) have a non-empty rectangle in common. This will always beFalse
if either is infinite or empty.
-
normalize
()¶ Replace the rectangle with its finite version. This is done by shuffling the rectangle corners. After completion of this method, the bottom right corner will indeed be south-eastern to the top left one.
-
irect
¶ Equals result of method
round()
.
-
top_left
¶
-
top_right
¶
-
bottom_left
¶
-
bottom_right
¶
-
width
¶ Width of the rectangle. Equals
abs(x1 - x0)
.- Return type
float
-
height
¶ Height of the rectangle. Equals
abs(y1 - y0)
.- Return type
float
-
x0
¶ X-coordinate of the left corners.
- Type
float
-
y0
¶ Y-coordinate of the top corners.
- Type
float
-
x1
¶ X-coordinate of the right corners.
- Type
float
-
y1
¶ Y-coordinate of the bottom corners.
- Type
float
-
isInfinite
¶ True
if rectangle is infinite,False
otherwise.- Type
bool
-
isEmpty
¶ True
if rectangle is empty,False
otherwise.- Type
bool
-
Remark¶
This class adheres to the sequence protocol, so components can be accessed via their index, too. Also refer to Using Python Sequences as Arguments in PyMuPDF.
Rect Algebra¶
For a general background, see chapter Operator Algebra for Geometry Objects.
Examples¶
Example 1 – different ways of construction:
>>> p1 = fitz.Point(10, 10)
>>> p2 = fitz.Point(300, 450)
>>>
>>> fitz.Rect(p1, p2)
fitz.Rect(10.0, 10.0, 300.0, 450.0)
>>>
>>> fitz.Rect(10, 10, 300, 450)
fitz.Rect(10.0, 10.0, 300.0, 450.0)
>>>
>>> fitz.Rect(10, 10, p2)
fitz.Rect(10.0, 10.0, 300.0, 450.0)
>>>
>>> fitz.Rect(p1, 300, 450)
fitz.Rect(10.0, 10.0, 300.0, 450.0)
Example 2 – what happens during rounding:
>>> r = fitz.Rect(0.5, -0.01, 123.88, 455.123456)
>>>
>>> r
fitz.Rect(0.5, -0.009999999776482582, 123.87999725341797, 455.1234436035156)
>>>
>>> r.round() # = r.irect
fitz.IRect(0, -1, 124, 456)
Example 3 – inclusion and itersection:
>>> m = fitz.Matrix(45)
>>> r = fitz.Rect(10, 10, 410, 610)
>>> r * m
fitz.Rect(-424.2640686035156, 14.142135620117188, 282.84271240234375, 721.2489013671875)
>>>
>>> r | fitz.Point(5, 5)
fitz.Rect(5.0, 5.0, 410.0, 610.0)
>>>
>>> r + 5
fitz.Rect(15.0, 15.0, 415.0, 615.0)
>>>
>>> r & fitz.Rect(0, 0, 15, 15)
fitz.Rect(10.0, 10.0, 15.0, 15.0)
Example 4 – containment:
>>> r = fitz.Rect(...) # any rectangle
>>> ir = r.irect # its IRect version
>>> # even though you get ...
>>> ir in r
True
>>> # ... and ...
>>> r in ir
True
>>> # ... r and ir are still different types!
>>> r == ir
False
>>> # corners are always part of non-epmpty rectangles
>>> r.bottom_left in r
True
>>>
>>> # numbers are checked against coordinates
>>> r.x0 in r
True
Example 5 – create a finite copy:
Create a copy that is guarantied to be finite in two ways:
>>> r = fitz.Rect(...) # any rectangle
>>>
>>> # alternative 1
>>> s = fitz.Rect(r.top_left, r.top_left) # just a point
>>> s | r.bottom_right # s is a finite rectangle!
>>>
>>> # alternative 2
>>> s = (+r).normalize()
>>> # r.normalize() changes r itself!
Example 6 – adding a Python sequence:
Enlarge rectangle by 5 pixels in every direction:
>>> r = fitz.Rect(...)
>>> r1 = r + (-5, -5, 5, 5)
Example 7 – inline operations:
Replace a rectangle with its transformation by the inverse of a matrix-like object:
>>> r /= (1, 2, 3, 4, 5, 6)