displayio/_area.py

   1 # SPDX-FileCopyrightText: 2021 Melissa LeBlanc-Williams for Adafruit Industries
   2 # SPDX-FileCopyrightText: 2021 James Carr
   3 #
   4 # SPDX-License-Identifier: MIT
   5
   6 """
   7 `displayio._area`
   8 ================================================================================
   9
  10 Area for Blinka Displayio
  11
  12 **Software and Dependencies:**
  13
  14 * Adafruit Blinka:
  15   https://github.com/adafruit/Adafruit_Blinka/releases
  16
  17 * Author(s): James Carr, Melissa LeBlanc-Williams
  18
  19 """
  20
  21 from __future__ import annotations
  22
  23 __version__ = "0.0.0+auto.0"
  24 __repo__ = "https://github.com/adafruit/Adafruit_Blinka_Displayio.git"
  25
  26
  27 class Area:
  28     """Area Class to represent an area to be updated."""
  29
  30     # pylint: disable=invalid-name
  31     def __init__(self, x1: int = 0, y1: int = 0, x2: int = 0, y2: int = 0):
  32         self.x1 = x1
  33         self.y1 = y1
  34         self.x2 = x2
  35         self.y2 = y2
  36         self.next = None
  37
  38     def __str__(self):
  39         return f"Area TL({self.x1},{self.y1}) BR({self.x2},{self.y2})"
  40
  41     def _copy_into(self, dst) -> None:
  42         dst.x1 = self.x1
  43         dst.y1 = self.y1
  44         dst.x2 = self.x2
  45         dst.y2 = self.y2
  46
  47     def _scale(self, scale: int) -> None:
  48         self.x1 *= scale
  49         self.y1 *= scale
  50         self.x2 *= scale
  51         self.y2 *= scale
  52
  53     def _shift(self, dx: int, dy: int) -> None:
  54         self.x1 += dx
  55         self.y1 += dy
  56         self.x2 += dx
  57         self.y2 += dy
  58
  59     def compute_overlap(self, other, overlap) -> bool:
  60         """Compute the overlap between two areas. Returns True if there is an overlap."""
  61         a = self
  62         overlap.x1 = max(a.x1, other.x1)
  63         overlap.x2 = min(a.x2, other.x2)
  64
  65         if overlap.x1 >= overlap.x2:
  66             return False
  67
  68         overlap.y1 = max(a.y1, other.y1)
  69         overlap.y2 = min(a.y2, other.y2)
  70
  71         return overlap.y1 < overlap.y2
  72
  73     def _empty(self):
  74         return (self.x1 == self.x2) or (self.y1 == self.y2)
  75
  76     def _canon(self):
  77         if self.x1 > self.x2:
  78             self.x1, self.x2 = self.x2, self.x1
  79         if self.y1 > self.y2:
  80             self.y1, self.y2 = self.y2, self.y1
  81
  82     def _union(self, other, union):
  83         if self._empty():
  84             self._copy_into(union)
  85             return
  86         if other._empty():  # pylint: disable=protected-access
  87             other._copy_into(union)  # pylint: disable=protected-access
  88             return
  89
  90         union.x1 = min(self.x1, other.x1)
  91         union.y1 = min(self.y1, other.y1)
  92         union.x2 = max(self.x2, other.x2)
  93         union.y2 = max(self.y2, other.y2)
  94
  95     def width(self) -> int:
  96         """Return the width of the area."""
  97         return self.x2 - self.x1
  98
  99     def height(self) -> int:
 100         """Return the height of the area."""
 101         return self.y2 - self.y1
 102
 103     def size(self) -> int:
 104         """Return the size of the area."""
 105         return self.width() * self.height()
 106
 107     def __eq__(self, other):
 108         if not isinstance(other, Area):
 109             return False
 110
 111         return (
 112             self.x1 == other.x1
 113             and self.y1 == other.y1
 114             and self.x2 == other.x2
 115             and self.y2 == other.y2
 116         )
 117
 118     @staticmethod
 119     def transform_within(
 120         mirror_x: bool,
 121         mirror_y: bool,
 122         transpose_xy: bool,
 123         original: Area,
 124         whole: Area,
 125         transformed: Area,
 126     ):
 127         """Transform an area within a larger area."""
 128         # pylint: disable=too-many-arguments
 129         # Original and whole must be in the same coordinate space.
 130         if mirror_x:
 131             transformed.x1 = whole.x1 + (whole.x2 - original.x2)
 132             transformed.x2 = whole.x2 - (original.x1 - whole.x1)
 133         else:
 134             transformed.x1 = original.x1
 135             transformed.x2 = original.x2
 136
 137         if mirror_y:
 138             transformed.y1 = whole.y1 + (whole.y2 - original.y2)
 139             transformed.y2 = whole.y2 - (original.y1 - whole.y1)
 140         else:
 141             transformed.y1 = original.y1
 142             transformed.y2 = original.y2
 143
 144         if transpose_xy:
 145             y1 = transformed.y1
 146             y2 = transformed.y2
 147             transformed.y1 = whole.y1 + (transformed.x1 - whole.x1)
 148             transformed.y2 = whole.y1 + (transformed.x2 - whole.x1)
 149             transformed.x1 = whole.x1 + (y1 - whole.y1)
 150             transformed.x2 = whole.x1 + (y2 - whole.y1)