Quad
Represents a foursided mathematical shape (also called “quadrilateral” or “tetragon”) in the plane, defined as a sequence of four Point objects ul, ur, ll, lr (conveniently called upper left, upper right, lower left, lower right).
Quads can be obtained as results of text search methods (Page.search_for()
), and they are used to define text marker annotations (see e.g. Page.add_squiggly_annot()
and friends), and in several draw methods (like Page.draw_quad()
/ Shape.draw_quad()
, Page.draw_oval()
/ Shape.draw_quad()
).
Note
If the corners of a rectangle are transformed with a rotation, scale or translation Matrix, then the resulting quad is rectangular (= congruent to a rectangle), i.e. all of its corners again enclose angles of 90 degrees. Property
Quad.is_rectangular
checks whether a quad can be thought of being the result of such an operation.This is not true for all matrices: e.g. shear matrices produce parallelograms, and noninvertible matrices deliver “degenerate” tetragons like triangles or lines.
Attribute
Quad.rect
obtains the envelopping rectangle. Vice versa, rectangles now have attributesRect.quad
, resp.IRect.quad
to obtain their respective tetragon versions.
Methods / Attributes 
Short Description 

transform with a matrix 

transform with a point and matrix 

upper left point 

upper right point 

lower left point 

lower right point 

true if quad is a convex set 

true if quad is an empty set 

true if quad is congruent to a rectangle 

smallest containing Rect 

the longest width value 

the longest height value 
Class API
 class Quad
 __init__(self)
 __init__(self, ul, ur, ll, lr)
 __init__(self, quad)
 __init__(self, sequence)
Overloaded constructors: “ul”, “ur”, “ll”, “lr” stand for
point_like
objects (the four corners), “sequence” is a Python sequence with fourpoint_like
objects.If “quad” is specified, the constructor creates a new copy of it.
Without parameters, a quad consisting of 4 copies of Point(0, 0) is created.
 transform(matrix)
Modify the quadrilateral by transforming each of its corners with a matrix.
 Parameters
matrix (matrix_like) – the matrix.
 morph(fixpoint, matrix)
(New in version 1.17.0) “Morph” the quad with a matrixlike using a pointlike as fixed point.
 Parameters
fixpoint (point_like) – the point.
matrix (matrix_like) – the matrix.
 Returns
a new quad (no operation if this is the infinite quad).
 rect
The smallest rectangle containing the quad, represented by the blue area in the following picture.
 Type
 is_convex
New in version 1.16.1
Checks if for any two points of the quad, all points on their connecting line also belong to the quad.
 Type
bool
 is_empty
True if enclosed area is zero, which means that at least three of the four corners are on the same line. If this is false, the quad may still be degenerate or not look like a tetragon at all (triangles, parallelograms, trapezoids, …).
 Type
bool
 is_rectangular
True if all corner angles are 90 degrees. This implies that the quad is convex and not empty.
 Type
bool
 width
The maximum length of the top and the bottom side.
 Type
float
 height
The maximum length of the left and the right side.
 Type
float
Remark
This class adheres to the sequence protocol, so components can be dealt with via their indices, too. Also refer to Using Python Sequences as Arguments in PyMuPDF.
Algebra and Containment Checks
Starting with v1.19.6, quads can be used in algebraic expressions like the other geometry object – the respective restrictions have been lifted. In particular, all the following combinations of containment checking are now possible:
{Point  IRect  Rect  Quad} in {IRect  Rect  Quad}
Please note the following interesting detail:
For a rectangle, only its topleft point belongs to it. Since v1.19.0, rectangles are defined to be “open”, such that its bottom and its right edge do not belong to it – including the respective corners. But for quads there exists no such notion like “openness”, so we have the following somewhat surprising implication:
>>> rect.br in rect
False
>>> # but:
>>> rect.br in rect.quad
True