"""
Drawing text with pyglet label
"""
import math
from typing import Tuple, Union
import arcade
import pyglet
from arcade.arcade_types import Color, Point
from arcade.draw_commands import get_four_byte_color
from pyglet.math import Mat4
from arcade.resources import resolve_resource_path
[docs]def load_font(font_name) -> None:
"""
Load a font for later use.
:param font_name:
:raises FileNotFoundError: if the font specified wasn't found
:return:
"""
# search resources folder for the named font, and error if it doesn't exist
if font_name.startswith(":resources:"):
try:
file_path = resolve_resource_path(font_name)
except FileNotFoundError:
raise FileNotFoundError(f"Unable to find resource with the name: {font_name}")
else:
file_path = font_name
pyglet.font.add_file(str(file_path))
FontNameOrNames = Union[str, Tuple[str, ...]]
def _attempt_font_name_resolution(font_name: FontNameOrNames) -> FontNameOrNames:
"""
Attempt to resolve a tuple of font names.
Preserves the original logic of this section, even though it
doesn't seem to make sense entirely. Comments are an attempt
to make sense of the original code.
If it can't resolve a definite path, it will return the original
argument for pyglet to attempt to resolve. This is consistent with
the original behavior of this code before it was encapsulated.
:param Union[str, Tuple[str, ...]] font_name:
:return: Either a resolved path or the original tuple
"""
if font_name:
# ensure
if isinstance(font_name, str):
font_list: Tuple[str, ...] = (font_name,)
elif isinstance(font_name, tuple):
font_list = font_name
else:
raise TypeError("font_name parameter must be a string, or a tuple of strings that specify a font name.")
for font in font_list:
try:
path = resolve_resource_path(font)
# print(f"Font path: {path=}")
# found a font successfully!
return path.name
except FileNotFoundError:
pass
# failed to find it ourselves, hope pyglet can make sense of it
return font_name
def _draw_label_with_rotation(label: pyglet.text.Label, rotation: float) -> None:
"""
Helper for drawing pyglet labels with rotation within arcade.
Originally part of draw_text in this module, now abstracted and improved
so that both arcade.Text and arcade.draw_text can make use of it.
:param pyglet.text.Label label: a pyglet label to wrap and draw
:param float rotation: rotate this many degrees from horizontal around anchor
"""
# raw pyglet draw functions need this context helper inside arcade
window = arcade.get_window()
with window.ctx.pyglet_rendering():
# execute view matrix magic to rotate cleanly
if rotation:
# original_view = window.view
angle_radians = math.radians(rotation)
x = label.x
y = label.y
label.x = 0
label.y = 0
r_view = Mat4.from_rotation(angle_radians, (0, 0, 1))
t_view = Mat4.from_translation((x, y, 0))
final_view = r_view @ t_view
window.view = final_view
label.draw()
# restore original position if we used view matrix magic
if rotation:
# linters might warn that this is used before assignment,
# but it's actually valid since we only use it when it was
# previously assigned.
label.x, label.y = x, y
[docs]class Text:
"""
An object-oriented way to draw text to the screen.
.. tip:: Use this class when performance matters!
Unlike :py:func:`~arcade.draw_text`, this class does not risk
wasting time recalculating and re-setting any text each time
:py:meth:`~arcade.Text.draw` is called. This makes it faster
while:
- requiring you to manage instances and drawing yourself
- using negligible extra RAM
The speed advantage scales as more text needs to be drawn
to the screen.
The constructor arguments work identically to those of
:py:func:`~arcade.draw_text`. See its documentation for in-depth
explanation for how to use each of them.
:param str text: Initial text to display. Can be an empty string
:param float start_x: x position to align the text's anchor point with
:param float start_y: y position to align the text's anchor point with
:param Color color: Color of the text as a tuple or list of 3 (RGB) or 4 (RGBA) integers
:param float font_size: Size of the text in points
:param float width: A width limit in pixels
:param str align: Horizontal alignment; values other than "left" require width to be set
:param Union[str, Tuple[str, ...]] font_name: A font name, path to a font file, or list of names
:param bool bold: Whether to draw the text as bold
:param bool italic: Whether to draw the text as italic
:param str anchor_x: How to calculate the anchor point's x coordinate
:param str anchor_y: How to calculate the anchor point's y coordinate
:param bool multiline: Requires width to be set; enables word wrap rather than clipping
:param float rotation: rotation in degrees, counter-clockwise from horizontal
All constructor arguments other than ``text`` have a corresponding
property. To access the current text, use the ``value`` property
instead.
By default, the text is placed so that:
- the left edge of its bounding box is at ``start_x``
- its baseline is at ``start_y``
The baseline is located along the line the bottom of the text would
be written on, excluding letters with tails such as y:
.. figure:: ../images/text_anchor_y.png
:width: 40%
The blue line is the baseline for the string ``"Python"``
``rotation`` allows for the text to be rotated around the anchor
point by the passed number of degrees. Positive values rotate
counter-clockwise from horizontal, while negative values rotate
clockwise:
.. figure:: ../images/text_rotation_degrees.png
:width: 55%
Rotation around the default anchor (
``anchor_y="baseline"`` and ``anchor_x="left"``)
"""
def __init__(
self,
text: str,
start_x: float,
start_y: float,
color: Color = arcade.color.WHITE,
font_size: float = 12,
width: int = 0,
align: str = "left",
font_name: FontNameOrNames = ("calibri", "arial"),
bold: bool = False,
italic: bool = False,
anchor_x: str = "left",
anchor_y: str = "baseline",
multiline: bool = False,
rotation: float = 0
):
"""Build a text object"""
if align != "center" and align != "left" and align != "right":
raise ValueError("The 'align' parameter must be equal to 'left', 'right', or 'center'.")
if align != "left":
multiline = True
adjusted_font = _attempt_font_name_resolution(font_name)
self._label = pyglet.text.Label(
text=text,
x=start_x,
y=start_y,
font_name=adjusted_font,
font_size=font_size,
anchor_x=anchor_x,
anchor_y=anchor_y,
color=get_four_byte_color(color),
width=width,
align=align,
bold=bold,
italic=italic,
multiline=multiline
)
self.rotation = rotation
@property
def value(self) -> str:
"""
The current value to display.
"""
return self._label.text
@value.setter
def value(self, value: str):
self._label.text = value
@property
def x(self) -> float:
return self._label.x
@x.setter
def x(self, x: float) -> None:
self._label.x = x
@property
def y(self) -> float:
return self._label.y
@y.setter
def y(self, y: float):
self._label.y = y
@property
def font_name(self) -> FontNameOrNames:
return self._label.font_name
@font_name.setter
def font_name(self, font_name: FontNameOrNames) -> None:
self._label.font_name = font_name
@property
def font_size(self) -> float:
return self._label.font_size
@font_size.setter
def font_size(self, font_size: float):
self._label.font_size = font_size
@property
def anchor_x(self) -> str:
return self._label.anchor_x
@anchor_x.setter
def anchor_x(self, anchor_x: str):
self._label.anchor_x = anchor_x
@property
def anchor_y(self) -> str:
return self._label.anchor_y
@anchor_y.setter
def anchor_y(self, anchor_y: str):
self._label.anchor_y = anchor_y
@property
def color(self) -> Color:
return self._label.color
@color.setter
def color(self, color: Color):
self._label.color = get_four_byte_color(color)
@property
def width(self) -> int:
return self._label.width
@width.setter
def width(self, width: int):
self._label.width = width
@property
def align(self) -> str:
return self._label.get_style("align") # type: ignore
@align.setter
def align(self, align: str):
# duplicates the logic used in the rest of this module
if align != "left":
self.multiline = True
self._label.set_style("align", align)
@property
def bold(self) -> bool:
return self._label.bold
@bold.setter
def bold(self, bold: bool):
self._label.bold = bold
@property
def italic(self) -> bool:
return self._label.italic
@italic.setter
def italic(self, italic: bool):
self._label.italic = italic
@property
def multiline(self) -> bool:
return self._label.multiline
@multiline.setter
def multiline(self, multiline: bool):
self._label.multiline = multiline
[docs] def draw(self) -> None:
"""
Draw this label to the screen at its current ``x`` and ``y`` position.
.. warning: Cameras affect text drawing!
If you want to draw a custom GUI that doesn't move with the
game world, you will need a second :py:class:`~arcade.Camera`
instance. For information on how to do this, see
:ref:`sprite_move_scrolling`.
"""
_draw_label_with_rotation(self._label, self.rotation)
@property
def position(self) -> Point:
"""
The current x, y position as a tuple. This wraps x and y.
"""
return self._label.x, self._label.y
@position.setter
def position(self, point: Point):
self._label.x, self._label.y = point
[docs]def draw_text(
text: str,
start_x: float,
start_y: float,
color: Color = arcade.color.WHITE,
font_size: float = 12,
width: int = 0,
align: str = "left",
font_name: FontNameOrNames = ("calibri", "arial"),
bold: bool = False,
italic: bool = False,
anchor_x: str = "left",
anchor_y: str = "baseline",
multiline: bool = False,
rotation: float = 0,
):
"""
A simple way for beginners to draw text.
.. warning:: Cameras affect text drawing!
If you want to draw a custom GUI that doesn't move with the
game world, you will need a second camera. For information on
how to do this, see :ref:`sprite_move_scrolling`.
This function lets you start draw text easily with better
performance than the old pillow-based text. If you need even higher
performance, consider using :py:class:`~arcade.Text`.
:param str text: Text to display
:param float start_x: x position to align the text's anchor point with
:param float start_y: y position to align the text's anchor point with
:param Color color: Color of the text as a tuple or list of 3 (RGB) or 4 (RGBA) integers
:param float font_size: Size of the text in points
:param float width: A width limit in pixels
:param str align: Horizontal alignment; values other than "left" require width to be set
:param Union[str, Tuple[str, ...]] font_name: A font name, path to a font file, or list of names
:param bool bold: Whether to draw the text as bold
:param bool italic: Whether to draw the text as italic
:param str anchor_x: How to calculate the anchor point's x coordinate
:param str anchor_y: How to calculate the anchor point's y coordinate
:param bool multiline: Requires width to be set; enables word wrap rather than clipping
:param float rotation: rotation in degrees, counter-clockwise from horizontal
By default, the text is placed so that:
- the left edge of its bounding box is at ``start_x``
- its baseline is at ``start_y``
The baseline of text is the line it would be written on:
.. figure:: ../images/text_anchor_y.png
:width: 40%
The blue line is the baseline for the string ``"Python"``
``font_name`` can be any of the following:
- a built-in font in the :ref:`Resources`
- the name of a system font
- a path to a font on the system
- a `tuple` containing any mix of the previous three
Each entry provided will be tried in order until one is found. If
none of the fonts are found, a default font will be chosen (usually
Arial).
``anchor_x`` and ``anchor_y`` specify how to calculate the anchor point,
which affects how the text is:
- Placed relative to ``start_x`` and ``start_y``
- Rotated
By default, the text is drawn so that ``start_x`` is at the left of
the text's bounding box and ``start_y`` is at the baseline.
You can set a custom anchor point by passing combinations of the
following values for ``anchor_x`` and ``anchor_y``:
.. list-table:: Values allowed by ``anchor_x``
:widths: 20 40 40
:header-rows: 1
* - String value
- Practical Effect
- Anchor Position
* - ``"left"`` `(default)`
- Text drawn with its left side at ``start_x``
- Anchor point at the left side of the text's bounding box
* - ``"center"``
- Text drawn horizontally centered on ``start_x``
- Anchor point at horizontal center of text's bounding box
* - ``"right"``
- Text drawn with its right side at ``start_x``
- Anchor placed at the right side of the text's bounding box
.. list-table:: Values allowed by ``anchor_y``
:widths: 20 40 40
:header-rows: 1
* - String value
- Practical Effect
- Anchor Position
* - ``"baseline"`` `(default)`
- Text drawn with baseline on ``start_y``.
- Anchor placed at the text rendering baseline
* - ``"top"``
- Text drawn with its top aligned with ``start_y``
- Anchor point placed at the top of the text
* - ``"bottom"``
- Text drawn with its absolute bottom aligned with ``start_y``,
including the space for tails on letters such as y and g
- Anchor point placed at the bottom of the text after the
space allotted for letters such as y and g
* - ``"center"``
- Text drawn with its vertical center on ``start_y``
- Anchor placed at the vertical center of the text
``rotation`` allows for the text to be rotated around the anchor
point by the passed number of degrees. Positive values rotate
counter-clockwise from horizontal, while negative values rotate
clockwise:
.. figure:: ../images/text_rotation_degrees.png
:width: 55%
Rotation around the default anchor point (
``anchor_y="baseline"`` and ``anchor_x="left"``)
It can be helpful to think of this function working as follows:
1. Text layout and alignment are calculated:
1. The text's characters are laid out within a bounding box
according to the current styling options
2. The anchor point on the text is calculated based on
the text value, styling, as well as values for ``anchor_x``
and ``anchor_y``
2. The text is placed so its anchor point is at ``(start_x,
start_y))``
3. The text is rotated around its anchor point before finally
being drawn
This function is less efficient than using :py:class:`~arcade.Text`
because some of the steps above can be repeated each time a call is
made rather than fully cached as with the class.
"""
# See : https://github.com/pyglet/pyglet/blob/ff30eadc2942553c9de96d6ce564ad1bc3128fb4/pyglet/text/__init__.py#L401
color = get_four_byte_color(color)
# Cache the states that are expensive to change
key = f"{font_size}{font_name}{bold}{italic}{anchor_x}{anchor_y}{align}{width}"
cache = arcade.get_window().ctx.pyglet_label_cache
label = cache.get(key)
if align != "center" and align != "left" and align != "right":
raise ValueError("The 'align' parameter must be equal to 'left', 'right', or 'center'.")
if align != "left":
multiline = True
if not label:
adjusted_font = _attempt_font_name_resolution(font_name)
label = pyglet.text.Label(
text=text,
x=start_x,
y=start_y,
font_name=adjusted_font,
font_size=font_size,
anchor_x=anchor_x,
anchor_y=anchor_y,
color=color,
width=width,
align=align,
bold=bold,
italic=italic,
multiline=multiline,
)
cache[key] = label
# These updates are relatively cheap
label.text = text
label.x = start_x
label.y = start_y
label.color = color
_draw_label_with_rotation(label, rotation)
# TODO: maybe remove, as this is invalid
[docs]def create_text(*args, **kwargs):
"""Legacy stub, returns a text object."""
return Text("Hello")