"""
Mixin class for managing a stack of graphics state variables.
The contents of this module are internal to fpdf2, and not part of the public API.
They may change at any time without prior warning or any deprecation period,
in non-backward-compatible ways.
"""
from copy import copy
from .drawing import DeviceGray
from .enums import CharVPos, TextEmphasis, TextMode
from .fonts import FontFace
class GraphicsStateMixin:
"""Mixin class for managing a stack of graphics state variables.
To the subclassing library and its users, the variables look like
normal instance attributes. But by the magic of properties, we can
push and pop levels as needed, and users will always see and modify
just the current version.
This class is mixed in by fpdf.FPDF(), and is not meant to be used
directly by user code.
"""
DEFAULT_DRAW_COLOR = DeviceGray(0)
DEFAULT_FILL_COLOR = DeviceGray(0)
DEFAULT_TEXT_COLOR = DeviceGray(0)
def __init__(self, *args, **kwargs):
self.__statestack = [
dict(
draw_color=self.DEFAULT_DRAW_COLOR,
fill_color=self.DEFAULT_FILL_COLOR,
text_color=self.DEFAULT_TEXT_COLOR,
underline=False,
font_style="",
font_stretching=100,
char_spacing=0,
font_family="",
font_size_pt=0,
current_font={},
dash_pattern=dict(dash=0, gap=0, phase=0),
line_width=0,
text_mode=TextMode.FILL,
char_vpos=CharVPos.LINE,
sub_scale=0.7,
sup_scale=0.7,
nom_scale=0.75,
denom_scale=0.75,
sub_lift=-0.15,
sup_lift=0.4,
nom_lift=0.2,
denom_lift=0.0,
text_shaping=None,
)
]
super().__init__(*args, **kwargs)
def _push_local_stack(self, new=None):
if new:
self.__statestack.append(new)
else:
self.__statestack.append(self._get_current_graphics_state())
def _pop_local_stack(self):
return self.__statestack.pop()
def _get_current_graphics_state(self):
# "current_font" must be shallow copied
# "text_shaping" must be deep copied (different fragments may have different languages/direction)
# Doing a whole copy and then creating a copy of text_shaping to achieve this result
gs = copy(self.__statestack[-1])
gs["text_shaping"] = copy(gs["text_shaping"])
return gs
def _is_current_graphics_state_nested(self):
return len(self.__statestack) > 1
@property
def draw_color(self):
return self.__statestack[-1]["draw_color"]
@draw_color.setter
def draw_color(self, v):
self.__statestack[-1]["draw_color"] = v
@property
def fill_color(self):
return self.__statestack[-1]["fill_color"]
@fill_color.setter
def fill_color(self, v):
self.__statestack[-1]["fill_color"] = v
@property
def text_color(self):
return self.__statestack[-1]["text_color"]
@text_color.setter
def text_color(self, v):
self.__statestack[-1]["text_color"] = v
@property
def underline(self):
return self.__statestack[-1]["underline"]
@underline.setter
def underline(self, v):
self.__statestack[-1]["underline"] = v
@property
def font_style(self):
return self.__statestack[-1]["font_style"]
@font_style.setter
def font_style(self, v):
self.__statestack[-1]["font_style"] = v
@property
def font_stretching(self):
return self.__statestack[-1]["font_stretching"]
@font_stretching.setter
def font_stretching(self, v):
self.__statestack[-1]["font_stretching"] = v
@property
def char_spacing(self):
return self.__statestack[-1]["char_spacing"]
@char_spacing.setter
def char_spacing(self, v):
self.__statestack[-1]["char_spacing"] = v
@property
def font_family(self):
return self.__statestack[-1]["font_family"]
@font_family.setter
def font_family(self, v):
self.__statestack[-1]["font_family"] = v
@property
def font_size_pt(self):
return self.__statestack[-1]["font_size_pt"]
@font_size_pt.setter
def font_size_pt(self, v):
self.__statestack[-1]["font_size_pt"] = v
@property
def font_size(self):
return self.__statestack[-1]["font_size_pt"] / self.k
@font_size.setter
def font_size(self, v):
self.__statestack[-1]["font_size_pt"] = v * self.k
@property
def current_font(self):
return self.__statestack[-1]["current_font"]
@current_font.setter
def current_font(self, v):
self.__statestack[-1]["current_font"] = v
@property
def dash_pattern(self):
return self.__statestack[-1]["dash_pattern"]
@dash_pattern.setter
def dash_pattern(self, v):
self.__statestack[-1]["dash_pattern"] = v
@property
def line_width(self):
return self.__statestack[-1]["line_width"]
@line_width.setter
def line_width(self, v):
self.__statestack[-1]["line_width"] = v
@property
def text_mode(self):
return self.__statestack[-1]["text_mode"]
@text_mode.setter
def text_mode(self, v):
self.__statestack[-1]["text_mode"] = TextMode.coerce(v)
@property
def char_vpos(self):
"""
Return vertical character position relative to line.
([docs](../TextStyling.html#subscript-superscript-and-fractional-numbers))
"""
return self.__statestack[-1]["char_vpos"]
@char_vpos.setter
def char_vpos(self, v):
"""
Set vertical character position relative to line.
([docs](../TextStyling.html#subscript-superscript-and-fractional-numbers))
"""
self.__statestack[-1]["char_vpos"] = CharVPos.coerce(v)
@property
def sub_scale(self):
"""
Return scale factor for subscript text.
([docs](../TextStyling.html#subscript-superscript-and-fractional-numbers))
"""
return self.__statestack[-1]["sub_scale"]
@sub_scale.setter
def sub_scale(self, v):
"""
Set scale factor for subscript text.
([docs](../TextStyling.html#subscript-superscript-and-fractional-numbers))
"""
self.__statestack[-1]["sub_scale"] = float(v)
@property
def sup_scale(self):
"""
Return scale factor for superscript text.
([docs](../TextStyling.html#subscript-superscript-and-fractional-numbers))
"""
return self.__statestack[-1]["sup_scale"]
@sup_scale.setter
def sup_scale(self, v):
"""
Set scale factor for superscript text.
([docs](../TextStyling.html#subscript-superscript-and-fractional-numbers))
"""
self.__statestack[-1]["sup_scale"] = float(v)
@property
def nom_scale(self):
"""
Return scale factor for nominator text.
([docs](../TextStyling.html#subscript-superscript-and-fractional-numbers))
"""
return self.__statestack[-1]["nom_scale"]
@nom_scale.setter
def nom_scale(self, v):
"""
Set scale factor for nominator text.
([docs](../TextStyling.html#subscript-superscript-and-fractional-numbers))
"""
self.__statestack[-1]["nom_scale"] = float(v)
@property
def denom_scale(self):
"""
Return scale factor for denominator text.
([docs](../TextStyling.html#subscript-superscript-and-fractional-numbers))
"""
return self.__statestack[-1]["denom_scale"]
@denom_scale.setter
def denom_scale(self, v):
"""
Set scale factor for denominator text.
([docs](../TextStyling.html#subscript-superscript-and-fractional-numbers))
"""
self.__statestack[-1]["denom_scale"] = float(v)
@property
def sub_lift(self):
"""
Return lift factor for subscript text.
([docs](../TextStyling.html#subscript-superscript-and-fractional-numbers))
"""
return self.__statestack[-1]["sub_lift"]
@sub_lift.setter
def sub_lift(self, v):
"""
Set lift factor for subscript text.
([docs](../TextStyling.html#subscript-superscript-and-fractional-numbers))
"""
self.__statestack[-1]["sub_lift"] = float(v)
@property
def sup_lift(self):
"""
Return lift factor for superscript text.
([docs](../TextStyling.html#subscript-superscript-and-fractional-numbers))
"""
return self.__statestack[-1]["sup_lift"]
@sup_lift.setter
def sup_lift(self, v):
"""
Set lift factor for superscript text.
([docs](../TextStyling.html#subscript-superscript-and-fractional-numbers))
"""
self.__statestack[-1]["sup_lift"] = float(v)
@property
def nom_lift(self):
"""
Return lift factor for nominator text.
([docs](../TextStyling.html#subscript-superscript-and-fractional-numbers))
"""
return self.__statestack[-1]["nom_lift"]
@nom_lift.setter
def nom_lift(self, v):
"""
Set lift factor for nominator text.
([docs](../TextStyling.html#subscript-superscript-and-fractional-numbers))
"""
self.__statestack[-1]["nom_lift"] = float(v)
@property
def denom_lift(self):
"""
Return lift factor for denominator text.
([docs](../TextStyling.html#subscript-superscript-and-fractional-numbers))
"""
return self.__statestack[-1]["denom_lift"]
@denom_lift.setter
def denom_lift(self, v):
"""
Set lift factor for denominator text.
([docs](../TextStyling.html#subscript-superscript-and-fractional-numbers))
"""
self.__statestack[-1]["denom_lift"] = float(v)
@property
def text_shaping(self):
return self.__statestack[-1]["text_shaping"]
@text_shaping.setter
def text_shaping(self, v):
self.__statestack[-1]["text_shaping"] = v
def font_face(self):
"""
Return a `fpdf.fonts.FontFace` instance
representing a subset of properties of this GraphicsState.
"""
return FontFace(
family=self.font_family,
emphasis=TextEmphasis.coerce(self.font_style),
size_pt=self.font_size_pt,
color=(
self.text_color if self.text_color != self.DEFAULT_TEXT_COLOR else None
),
fill_color=(
self.fill_color if self.fill_color != self.DEFAULT_FILL_COLOR else None
),
)