roundrect.py

# SPDX-FileCopyrightText: 2019 Limor Fried for Adafruit Industries
#
# SPDX-License-Identifier: MIT

"""
`roundrect`
================================================================================

A slightly modified version of Adafruit_CircuitPython_Display_Shapes that includes
an explicit call to palette.make_opaque() in the fill color setter function.

"""

try:
    from typing import Optional
except ImportError:
    pass

import displayio

__version__ = "0.0.0+auto.0"
__repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_Display_Shapes.git"


class RoundRect(displayio.TileGrid):
    # pylint: disable=too-many-arguments
    """A round-corner rectangle.

    :param int x: The x-position of the top left corner.
    :param int y: The y-position of the top left corner.
    :param int width: The width of the rounded-corner rectangle.
    :param int height: The height of the rounded-corner rectangle.
    :param int r: The radius of the rounded corner.
    :param int|None fill: The color to fill the rounded-corner rectangle. Can be a hex value
                    for a color or ``None`` for transparent.
    :param int|None outline: The outline of the rounded-corner rectangle. Can be a hex value
                    for a color or ``None`` for no outline.
    :param int stroke: Used for the outline. Will not change the outer bound size set by ``width``
                    and ``height``.

    """

    def __init__(
        self,
        x: int,
        y: int,
        width: int,
        height: int,
        r: int,
        *,
        fill: Optional[int] = None,
        outline: Optional[int] = None,
        stroke: int = 1,
    ) -> None:
        if width <= 0 or height <= 0:
            raise ValueError("Rectangle dimensions must be larger than 0.")
        if r > width / 2 or r > height / 2:
            raise ValueError(
                "Radius cannot exceed half of the smaller side (width or height)."
            )

        self._palette = displayio.Palette(3)
        self._palette.make_transparent(0)
        self._bitmap = displayio.Bitmap(width, height, 3)
        for i in range(0, width):  # draw the center chunk
            for j in range(r, height - r):  # draw the center chunk
                self._bitmap[i, j] = 2
        self._helper(
            r,
            r,
            r,
            color=2,
            fill=True,
            x_offset=width - 2 * r - 1,
            y_offset=height - 2 * r - 1,
        )

        if fill is not None:
            self._palette[2] = fill
            self._palette.make_opaque(2)
        else:
            self._palette.make_transparent(2)
            self._palette[2] = 0

        if outline is not None:
            self._palette[1] = outline
            # draw flat sides
            for w in range(r, width - r):
                for line in range(stroke):
                    self._bitmap[w, line] = 1
                    self._bitmap[w, height - line - 1] = 1
            for _h in range(r, height - r):
                for line in range(stroke):
                    self._bitmap[line, _h] = 1
                    self._bitmap[width - line - 1, _h] = 1
            # draw round corners
            self._helper(
                r,
                r,
                r,
                color=1,
                stroke=stroke,
                x_offset=width - 2 * r - 1,
                y_offset=height - 2 * r - 1,
            )
        super().__init__(self._bitmap, pixel_shader=self._palette, x=x, y=y)

    # pylint: disable=invalid-name, too-many-locals, too-many-branches
    def _helper(
        self,
        x0: int,
        y0: int,
        r: int,
        *,
        color: int,
        x_offset: int = 0,
        y_offset: int = 0,
        stroke: int = 1,
        corner_flags: int = 0xF,
        fill: bool = False,
    ) -> None:
        f = 1 - r
        ddF_x = 1
        ddF_y = -2 * r
        x = 0
        y = r

        while x < y:
            if f >= 0:
                y -= 1
                ddF_y += 2
                f += ddF_y
            x += 1
            ddF_x += 2
            f += ddF_x
            if corner_flags & 0x8:
                if fill:
                    for w in range(x0 - y, x0 + y + x_offset):
                        self._bitmap[w, y0 + x + y_offset] = color
                    for w in range(x0 - x, x0 + x + x_offset):
                        self._bitmap[w, y0 + y + y_offset] = color
                else:
                    for line in range(stroke):
                        self._bitmap[x0 - y + line, y0 + x + y_offset] = color
                        self._bitmap[x0 - x, y0 + y + y_offset - line] = color
            if corner_flags & 0x1:
                if fill:
                    for w in range(x0 - y, x0 + y + x_offset):
                        self._bitmap[w, y0 - x] = color
                    for w in range(x0 - x, x0 + x + x_offset):
                        self._bitmap[w, y0 - y] = color
                else:
                    for line in range(stroke):
                        self._bitmap[x0 - y + line, y0 - x] = color
                        self._bitmap[x0 - x, y0 - y + line] = color
            if corner_flags & 0x4:
                for line in range(stroke):
                    self._bitmap[x0 + x + x_offset, y0 + y + y_offset - line] = color
                    self._bitmap[x0 + y + x_offset - line, y0 + x + y_offset] = color
            if corner_flags & 0x2:
                for line in range(stroke):
                    self._bitmap[x0 + x + x_offset, y0 - y + line] = color
                    self._bitmap[x0 + y + x_offset - line, y0 - x] = color

    # pylint: enable=invalid-name, too-many-locals, too-many-branches

    @property
    def fill(self) -> Optional[int]:
        """The fill of the rounded-corner rectangle. Can be a hex value for a color or ``None`` for
        transparent."""
        return self._palette[2]

    @fill.setter
    def fill(self, color: Optional[int]) -> None:
        if color is None:
            self._palette[2] = 0
            self._palette.make_transparent(2)
        else:
            self._palette[2] = color
            self._palette.make_opaque(2)

    @property
    def outline(self) -> Optional[int]:
        """The outline of the rounded-corner rectangle. Can be a hex value for a color or ``None``
        for no outline."""
        return self._palette[1]

    @outline.setter
    def outline(self, color: Optional[int]) -> None:
        if color is None:
            self._palette[1] = 0
            self._palette.make_transparent(1)
        else:
            self._palette[1] = color
            self._palette.make_opaque(2)

    @property
    def width(self) -> int:
        """
        :return: the width of the rounded rectangle in pixels
        """
        return self._bitmap.width

    @property
    def height(self) -> int:
        """
        :return: the height of the rounded rectangle in pixels
        """
        return self._bitmap.height