Apr 23, 2021 · Apr 24, 2021 · Apr 24, 2021 · Apr 24, 2021 · Apr 24, 2021 · Apr 24, 2021
diff --git a/lib/matplotlib/backends/backend_agg.py b/lib/matplotlib/backends/backend_agg.py
 except ImportError:
    import dummy_threading as threading
 from contextlib import nullcontext
 from math import radians, cos, sin
 from math import radians, cos, sin, sqrt

 import numpy as np
 from PIL import Image
        xo, yo = font.get_bitmap_offset()
        xo /= 64.0
        yo /= 64.0
        h = sqrt(xo**2 + yo**2)
        xd = d * sin(radians(angle))
        yd = d * cos(radians(angle))
        xo = h * cos(radians(angle))
        yo = h * sin(radians(angle))
        x = round(x + xo + xd)
        y = round(y + yo+ yd)
        y = round(y + yo- yd)
        self._renderer.draw_text_image(font, x, y + 1, angle, gc)

    def get_text_width_height_descent(self, s, prop, ismath):
Original file line number	Diff line number	Diff line change
Expand Up		@@ -24,7 +24,7 @@
		except ImportError:
		import dummy_threading as threading
		from contextlib import nullcontext
		from math import radians, cos, sin
		from math import radians, cos, sin, sqrt

		import numpy as np
		from PIL import Image
Expand DownExpand Up		@@ -208,10 +208,13 @@ def draw_text(self, gc, x, y, s, prop, angle, ismath=False, mtext=None):
		xo, yo = font.get_bitmap_offset()
		xo /= 64.0
		yo /= 64.0
		h = sqrt(xo2 + yo2)
Copy link Member WeatherGodApr 24, 2021 Choose a reason for hiding this comment The reason will be displayed to describe this comment to others.Learn more. Personally, I prefer using`hypot()` instead, but I don't know if it really matters in the context of bounding box calculations. Copy link Author safdarzareefApr 24, 2021 Choose a reason for hiding this comment The reason will be displayed to describe this comment to others.Learn more. I don't know if it will matter, but we could still change it.
		xd = d * sin(radians(angle))
		yd = d * cos(radians(angle))
		xo = h * cos(radians(angle))
		yo = h * sin(radians(angle))
Copy link Member WeatherGodApr 24, 2021 Choose a reason for hiding this comment The reason will be displayed to describe this comment to others.Learn more. If we are going to calculate`radians(angle)` four times, might as well just do it once and store it in a variable. safdarzareef reacted with thumbs up emoji Copy link Member WeatherGodApr 24, 2021 Choose a reason for hiding this comment The reason will be displayed to describe this comment to others.Learn more. Also, these four lines here would greatly benefit from a comment explaining the trigonometry. Usually, cos() goes with x, and y goes with sin(). Seeing it two different ways here for the offset and the descent is confusing. Copy link Author safdarzareefApr 24, 2021 Choose a reason for hiding this comment The reason will be displayed to describe this comment to others.Learn more. I can explain the offset trigonometry, but I just left the code for the descent as it was before. The descent seems wrong - but I am unaware of the reason why it was like that before so I left it there. Basic trigonometry suggests that x components should be calculated by multiplying a number by the cosine of its angle and y components should be calculated by multiplying a number by the sine of its angle - so that is why I used that for the offset but I do think the descent should be in the same form too.
		x = round(x + xo + xd)
		y = round(y + yo+ yd)
		y = round(y + yo- yd)
Copy link Member WeatherGodApr 24, 2021 Choose a reason for hiding this comment The reason will be displayed to describe this comment to others.Learn more. much like the trig above, I think this will also need a quick proof in the comments. Copy link Author safdarzareefApr 24, 2021 Choose a reason for hiding this comment The reason will be displayed to describe this comment to others.Learn more. I don't think I have a proof for this at the moment except that in the draw_mathtext function the y is calculated in a similar manner and by subtracting the y offset we get a satisfactory result.
		self._renderer.draw_text_image(font, x, y + 1, angle, gc)

		def get_text_width_height_descent(self, s, prop, ismath):
Expand Down