Add a dpi aware font wrapper type

piker/ui/_axes.py

@@ -1,21 +1,23 @@
 """
 Chart axes graphics and behavior.
 """
-from typing import List, Tuple
+from typing import List, Tuple, Optional
 
 import pandas as pd
 import pyqtgraph as pg
 from PyQt5 import QtCore, QtGui
 from PyQt5.QtCore import QPointF
 
-from ._style import _font, hcolor
+from ._style import DpiAwareFont, hcolor, _font
 from ..data._source import float_digits
 
 _axis_pen = pg.mkPen(hcolor('bracket'))
 
 
 class Axis(pg.AxisItem):
+    """A better axis that sizes to typical tick contents considering font size.
 
+    """
     def __init__(
         self,
         linked_charts,
@@ -27,10 +29,10 @@ class Axis(pg.AxisItem):
 
         super().__init__(**kwargs)
 
-        self.setTickFont(_font)
+        self.setTickFont(_font.font)
         self.setStyle(**{
             'textFillLimits': [(0, 0.666)],
-            'tickFont': _font,
+            'tickFont': _font.font,
             # 'tickTextWidth': 100,
             # 'tickTextHeight': 20,
             # 'tickTextWidth': 40,
@@ -42,9 +44,9 @@ class Axis(pg.AxisItem):
         })
         # self.setLabel(**{'font-size': '10pt'})
 
-        self.setTickFont(_font)
+        self.setTickFont(_font.font)
         self.setPen(_axis_pen)
-        self.typical_br = _font._fm.boundingRect(typical_max_str)
+        self.typical_br = _font._qfm.boundingRect(typical_max_str)
 
         # size the pertinent axis dimension to a "typical value"
         self.resize()
@@ -92,17 +94,18 @@ class DynamicDateAxis(Axis):
         self,
         indexes: List[int],
     ) -> List[str]:
+
         bars = self.linked_charts.chart._array
-        times = bars['time']
         bars_len = len(bars)
-        # delay = times[-1] - times[times != times[-1]][-1]
+        times = bars['time']
-        delay = times[-1] - times[-2]
 
         epochs = times[list(
             map(int, filter(lambda i: i < bars_len, indexes))
         )]
         # TODO: **don't** have this hard coded shift to EST
         dts = pd.to_datetime(epochs, unit='s')  # - 4*pd.offsets.Hour()
+
+        delay = times[-1] - times[-2]
         return dts.strftime(self.tick_tpl[delay])
 
     def tickStrings(self, values: List[float], scale, spacing):
@@ -111,9 +114,8 @@ class DynamicDateAxis(Axis):
 
 class AxisLabel(pg.GraphicsObject):
 
-    _font = _font
     _w_margin = 0
-    _h_margin = 3
+    _h_margin = 0
 
     def __init__(
         self,
@@ -122,46 +124,62 @@ class AxisLabel(pg.GraphicsObject):
         bg_color: str = 'bracket',
         fg_color: str = 'black',
         opacity: int = 1,
+        font_size: Optional[int] = None,
     ):
         super().__init__(parent)
         self.parent = parent
         self.opacity = opacity
         self.label_str = ''
         self.digits = digits
+
         self._txt_br: QtCore.QRect = None
 
+        self._dpifont = DpiAwareFont()
+        self._dpifont.configure_to_dpi(_font._screen)
+        if font_size is not None:
+            self._dpifont._set_qfont_px_size(font_size)
+
+        # self._font._fm = QtGui.QFontMetrics(self._font)
+
         self.bg_color = pg.mkColor(hcolor(bg_color))
         self.fg_color = pg.mkColor(hcolor(fg_color))
 
-        self.pic = QtGui.QPicture()
+        # self.pic = QtGui.QPicture()
-        p = QtGui.QPainter(self.pic)
+        # p = QtGui.QPainter(self.pic)
 
         self.rect = None
 
-        p.setPen(self.fg_color)
+        # p.setPen(self.fg_color)
-        p.setOpacity(self.opacity)
 
         self.setFlag(self.ItemIgnoresTransformations)
 
     def paint(self, p, option, widget):
-        p.drawPicture(0, 0, self.pic)
+        # p.drawPicture(0, 0, self.pic)
+        p.setCompositionMode(QtGui.QPainter.CompositionMode_SourceOver)
 
         if self.label_str:
 
             if not self.rect:
                 self._size_br_from_str(self.label_str)
 
-            p.setFont(_font)
+            p.setFont(self._dpifont.font)
             p.setPen(self.fg_color)
+            p.setOpacity(self.opacity)
             p.fillRect(self.rect, self.bg_color)
 
             # this adds a nice black outline around the label for some odd
             # reason; ok by us
             p.drawRect(self.rect)
 
-            p.drawText(option.rect, self.text_flags, self.label_str)
+            p.drawText(self.rect, self.text_flags, self.label_str)
 
     def boundingRect(self):  # noqa
+        # if self.label_str:
+        #     self._size_br_from_str(self.label_str)
+        #     return self.rect
+
+        # return QtCore.QRectF()
+
         return self.rect or QtCore.QRectF()
 
     def _size_br_from_str(self, value: str) -> None:
@@ -169,9 +187,21 @@ class AxisLabel(pg.GraphicsObject):
         around provided string contents.
 
         """
-        txt_br = self._font._fm.boundingRect(value)
+        # size the filled rect to text and/or parent axis
-        txt_h, txt_w = txt_br.height(), txt_br.width()
+        br = self._txt_br = self._dpifont.boundingRect(value)
+
+        # px_per_char = self._font._fm.averageCharWidth()
+        # br = br * 1.88
+        txt_h, txt_w = br.height(), br.width()
+        print(f'orig: {txt_h}')
+        # txt_h = (br.topLeft() - br.bottomRight()).y()
+        # txt_w = len(value) * px_per_char
+        # txt_w *= 1.88
+        # txt_h *= 1.88
+        # print(f'calced: {txt_h}')
+
         h, w = self.size_hint()
+
         self.rect = QtCore.QRectF(
             0, 0,
             (w or txt_w) + self._w_margin,
@@ -190,15 +220,12 @@ class AxisLabel(pg.GraphicsObject):
 
 class XAxisLabel(AxisLabel):
 
-    _w_margin = 8
+    _w_margin = 0
     _h_margin = 0
 
     text_flags = (
         QtCore.Qt.TextDontClip
         | QtCore.Qt.AlignCenter
-        # | QtCore.Qt.AlignTop
-        # | QtCore.Qt.AlignVCenter
-        # | QtCore.Qt.AlignHCenter
     )
 
     def size_hint(self) -> Tuple[float, float]:
@@ -211,43 +238,50 @@ class XAxisLabel(AxisLabel):
         data: float,  # data for text
         offset: int = 1  # if have margins, k?
     ) -> None:
+
         timestrs = self.parent._indexes_to_timestrs([int(data)])
 
         if not timestrs.any():
             return
 
         self.label_str = timestrs[0]
+
         width = self.boundingRect().width()
-        new_pos = QPointF(abs_pos.x() - width / 2 - offset, 0)
+        self.setPos(QPointF(
-        self.setPos(new_pos)
+            abs_pos.x() - width / 2, # - offset,
+            0
+        ))
 
 
 class YAxisLabel(AxisLabel):
 
     text_flags = (
-        QtCore.Qt.AlignLeft
+        # QtCore.Qt.AlignLeft
+        QtCore.Qt.AlignVCenter
         | QtCore.Qt.TextDontClip
-        | QtCore.Qt.AlignVCenter
     )
 
     def size_hint(self) -> Tuple[float, float]:
         # size to parent axis width
         return None, self.parent.width()
 
-    def tick_to_string(self, tick_pos):
-        # WTF IS THIS FORMAT?
-        return ('{: ,.%df}' % self.digits).format(tick_pos).replace(',', ' ')
-
     def update_label(
         self,
         abs_pos: QPointF,  # scene coords
         data: float,  # data for text
         offset: int = 1  # if have margins, k?
     ) -> None:
-        self.label_str = self.tick_to_string(data)
+
-        height = self.boundingRect().height()
+        # this is read inside ``.paint()``
-        new_pos = QPointF(0, abs_pos.y() - height / 2 - offset)
+        self.label_str = '{data: ,.{digits}f}'.format(
-        self.setPos(new_pos)
+            digits=self.digits, data=data).replace(',', ' ')
+
+        br = self.boundingRect()
+        h = br.height()
+        self.setPos(QPointF(
+            0,
+            abs_pos.y() - h / 2 #- offset
+        ))
 
 
 class YSticky(YAxisLabel):
@@ -264,29 +298,40 @@ class YSticky(YAxisLabel):
 
         self._chart = chart
         chart.sigRangeChanged.connect(self.update_on_resize)
+        self._last_datum = (None, None)
 
     def update_on_resize(self, vr, r):
         # TODO: add an `.index` to the array data-buffer layer
         # and make this way less shitty...
-        chart = self._chart
+        index, last = self._last_datum
-        a = chart._array
+        if index is not None:
-        fields = a.dtype.fields
-        if fields and 'close' in fields:
-            index, last = a[-1][['index', 'close']]
-        else:
-            # non-ohlc case
-            index = len(a) - 1
-            last = a[chart.name][-1]
             self.update_from_data(
                 index,
                 last,
             )
 
+        # chart = self._chart
+        # a = chart._array
+        # fields = a.dtype.fields
+
+        # if fields and 'close' in fields:
+        #     index, last = a[-1][['index', 'close']]
+
+        # else:  # non-ohlc case
+        #     index = len(a) - 1
+        #     last = a[chart.name][-1]
+
+        # self.update_from_data(
+        #     index,
+        #     last,
+        # )
+
     def update_from_data(
         self,
         index: int,
         value: float,
     ) -> None:
+        self._last_datum = (index, value)
         self.update_label(
             self._chart.mapFromView(QPointF(index, value)),
             value

piker/ui/_style.py

@@ -2,26 +2,70 @@
 Qt UI styling.
 """
 import pyqtgraph as pg
-from PyQt5 import QtGui
+from PyQt5 import QtCore, QtGui
 from qdarkstyle.palette import DarkPalette
 
 from ..log import get_logger
 
 log = get_logger(__name__)
 
+
+# def configure_font_to_dpi(screen: QtGui.QScreen):
+#     """Set an appropriately sized font size depending on the screen DPI.
+
+#     If we end up needing to generalize this more here there are resources
+#     listed in the script in ``snippets/qt_screen_info.py``.
+
+#     """
+#     dpi = screen.physicalDotsPerInch()
+#     font_size = round(_font_inches_we_like * dpi)
+#     log.info(
+#         f"\nscreen:{screen.name()} with DPI: {dpi}"
+#         f"\nbest font size is {font_size}\n"
+#     )
+
+#     global _font
+#     _font.setPixelSize(font_size)
+#     _font._fm = QtGui.QFontMetrics(_font)
+
+#     return _font
+
+
 # chart-wide font
 # font size 6px / 53 dpi (3x scaled down on 4k hidpi)
-_font_inches_we_like = 6 / 53
+_font_inches_we_like = 6 / 53  # px / (px / inch) = inch
-
-# use pixel size to be cross-resolution compatible?
-_font = QtGui.QFont("Hack")
-_font.setPixelSize(6)  # default
-
-# TODO: re-compute font size when main widget switches screens?
-# https://forum.qt.io/topic/54136/how-do-i-get-the-qscreen-my-widget-is-on-qapplication-desktop-screen-returns-a-qwidget-and-qobject_cast-qscreen-returns-null/3
 
 
-def configure_font_to_dpi(screen: QtGui.QScreen):
+class DpiAwareFont:
+    def __init__(
+        self,
+        name: str = 'Hack',
+    ) -> None:
+        self.name = name
+        self._qfont = QtGui.QFont(name)
+        self._iwl = _font_inches_we_like
+        self._qfm = QtGui.QFontMetrics(self._qfont)
+        self._font_size = None
+        self._physical_dpi = None
+        self._screen = None
+
+    def _set_qfont_px_size(self, px_size: int) -> None:
+        # self._qfont = QtGui.Qfont(self.name)
+        self._qfont.setPixelSize(px_size)
+        self._qfm = QtGui.QFontMetrics(self._qfont)
+
+    @property
+    def font(self):
+        return self._qfont
+
+    @property
+    def px_size(self):
+        return self._qfont.pixelSize()
+
+    # def set_px_size(self, size: int) -> None:
+    #     pass
+
+    def configure_to_dpi(self, screen: QtGui.QScreen):
         """Set an appropriately sized font size depending on the screen DPI.
 
         If we end up needing to generalize this more here there are resources
@@ -29,18 +73,57 @@ def configure_font_to_dpi(screen: QtGui.QScreen):
 
         """
         dpi = screen.physicalDotsPerInch()
-    font_size = round(_font_inches_we_like * dpi)
+        font_size = round(self._iwl * dpi)
         log.info(
             f"\nscreen:{screen.name()} with DPI: {dpi}"
             f"\nbest font size is {font_size}\n"
         )
+        self._set_qfont_px_size(font_size)
+        self._font_size = font_size
+        self._physical_dpi = dpi
+        self._screen = screen
 
-    global _font
+    def boundingRect(self, value: str) -> QtCore.QRectF:
-    _font.setPixelSize(font_size)
+        screen = self._screen
-    _font._fm = QtGui.QFontMetrics(_font)
+        if screen is None:
+            raise RuntimeError("You must call .configure_to_dpi() first!")
 
-    return _font
+        unscaled_br = self._qfm.boundingRect(value)
 
+        # XXX: for wtv absolutely fucked reason, the scaling only applies
+        # to everything when the current font size **is not** the size
+        # needed to get the original desired text height... :mindblow:
+        if self._font_size != 6:
+            # scalar = self._qfm.fontDpi() / self._physical_dpi
+            scalar = screen.logicalDotsPerInch() / screen.physicalDotsPerInch()
+            # scalar = 100 / screen.physicalDotsPerInch()
+            # assert 0
+            print(f'SCALAR {scalar}')
+
+
+            return QtCore.QRectF(
+                # unscaled_br.x(),
+                # unscaled_br.y(),
+                0,
+                0,
+                unscaled_br.width() * scalar,
+                unscaled_br.height() * scalar,
+            )
+        else:
+            return QtCore.QRectF(
+                # unscaled_br.x(),
+                # unscaled_br.y(),
+                0,
+                0,
+                unscaled_br.width(),
+                unscaled_br.height(),
+            )
+
+# use pixel size to be cross-resolution compatible?
+_font = DpiAwareFont()
+
+# TODO: re-compute font size when main widget switches screens?
+# https://forum.qt.io/topic/54136/how-do-i-get-the-qscreen-my-widget-is-on-qapplication-desktop-screen-returns-a-qwidget-and-qobject_cast-qscreen-returns-null/3
 
 # _i3_rgba = QtGui.QColor.fromRgbF(*[0.14]*3 + [1])
 
@@ -69,6 +152,7 @@ def hcolor(name: str) -> str:
     """Hex color codes by hipster speak.
     """
     return {
+
         # lives matter
         'black': '#000000',
         'erie_black': '#1B1B1B',
@@ -99,6 +183,9 @@ def hcolor(name: str) -> str:
         'vwap_blue': '#0582fb',
         'dodger_blue': '#1e90ff',  # like the team?
         'panasonic_blue': '#0040be',  # from japan
+        # 'bid_blue': '#0077ea',  # like the L1
+        'bid_blue': '#3094d9',  # like the L1
+        'aquaman': '#39abd0',
 
         # traditional
         'tina_green': '#00cc00',