Add basic poll rendering support for tldraw polls

The existing poll rendering code for pre-tldraw polls has been copy/
pasted and adjusted slightly to handle the different data structure
for the poll response data.

bbb_presentation_video/renderer/tldraw/shape/poll.py

@@ -7,9 +7,20 @@
 from typing import TypeVar
 
 import cairo
+from gi.repository import Pango, PangoCairo
 
+from bbb_presentation_video.events.helpers import Color
 from bbb_presentation_video.renderer.tldraw.shape import PollShape, apply_shape_rotation
 
+FONT_FAMILY = "Arial"
+POLL_BAR_COLOR = Color.from_int(0x333333)
+POLL_LINE_WIDTH = 2.0
+POLL_FONT_SIZE = 22
+POLL_BG = Color.from_int(0xFFFFFF)
+POLL_FG = Color.from_int(0x000000)
+POLL_VPADDING = 20.0
+POLL_HPADDING = 10.0
+
 CairoSomeSurface = TypeVar("CairoSomeSurface", bound=cairo.Surface)
 
 
@@ -18,4 +29,124 @@ def finalize_poll(
 ) -> None:
     print(f"\tTldraw: Finalizing Poll: {id}")
 
+    if len(shape.answers) == 0:
+        return
+
     apply_shape_rotation(ctx, shape)
+
+    width = shape.size.width
+    height = shape.size.height
+
+    ctx.set_line_join(cairo.LINE_JOIN_MITER)
+    ctx.set_line_cap(cairo.LINE_CAP_SQUARE)
+
+    # Draw the background and poll outline
+    half_lw = POLL_LINE_WIDTH / 2
+    ctx.set_line_width(POLL_LINE_WIDTH)
+    ctx.move_to(half_lw, half_lw)
+    ctx.line_to(width - half_lw, half_lw)
+    ctx.line_to(width - half_lw, height - half_lw)
+    ctx.line_to(half_lw, height - half_lw)
+    ctx.close_path()
+    ctx.set_source_rgb(*POLL_BG)
+    ctx.fill_preserve()
+    ctx.set_source_rgb(*POLL_FG)
+    ctx.stroke()
+
+    font = Pango.FontDescription()
+    font.set_family(FONT_FAMILY)
+    font.set_absolute_size(int(POLL_FONT_SIZE * Pango.SCALE))
+
+    # Use Pango to calculate the label width space needed
+    pctx = PangoCairo.create_context(ctx)
+    layout = Pango.Layout(pctx)
+    layout.set_font_description(font)
+
+    max_label_width = 0.0
+    max_percent_width = 0.0
+    for answer in shape.answers:
+        layout.set_text(answer.key, -1)
+        (label_width, _) = layout.get_pixel_size()
+        if label_width > max_label_width:
+            max_label_width = label_width
+        percent: str
+        if shape.numResponders > 0:
+            percent = "{}%".format(
+                int(float(answer.numVotes) / float(shape.numResponders) * 100)
+            )
+        else:
+            percent = "0%"
+        layout.set_text(percent, -1)
+        (percent_width, _) = layout.get_pixel_size()
+        if percent_width > max_percent_width:
+            max_percent_width = percent_width
+
+    max_label_width = min(max_label_width, width * 0.3)
+    max_percent_width = min(max_percent_width, width * 0.3)
+
+    bar_height = (height - POLL_VPADDING) / len(shape.answers) - POLL_VPADDING
+    bar_width = width - 4 * POLL_HPADDING - max_label_width - max_percent_width
+    bar_x = 2 * POLL_HPADDING + max_label_width
+
+    # All sizes are calculated, so draw the poll
+    for i, answer in enumerate(shape.answers):
+        bar_y = (bar_height + POLL_VPADDING) * i + POLL_VPADDING
+        if shape.numResponders > 0:
+            result_ratio = float(answer.numVotes) / float(shape.numResponders)
+        else:
+            result_ratio = 0.0
+        percent = "{}%".format(int(result_ratio * 100))
+
+        bar_x2 = bar_x + (bar_width * result_ratio)
+
+        # Draw the bar
+        ctx.set_line_width(POLL_LINE_WIDTH)
+        ctx.move_to(bar_x + half_lw, bar_y + half_lw)
+        ctx.line_to(max(bar_x + half_lw, bar_x2 - half_lw), bar_y + half_lw)
+        ctx.line_to(
+            max(bar_x + half_lw, bar_x2 - half_lw), bar_y + bar_height - half_lw
+        )
+        ctx.line_to(bar_x + half_lw, bar_y + bar_height - half_lw)
+        ctx.close_path()
+        ctx.set_source_rgb(*POLL_BAR_COLOR)
+        ctx.fill_preserve()
+        ctx.stroke()
+
+        # Draw the label and percentage
+        layout.set_ellipsize(Pango.EllipsizeMode.END)
+        ctx.set_source_rgb(*POLL_FG)
+        layout.set_width(int(max_label_width * Pango.SCALE))
+        layout.set_text(answer.key, -1)
+        label_width, label_height = layout.get_pixel_size()
+        ctx.move_to(
+            bar_x - POLL_HPADDING - label_width,
+            bar_y + (bar_height - label_height) / 2,
+        )
+        PangoCairo.show_layout(ctx, layout)
+        layout.set_width(int(max_percent_width * Pango.SCALE))
+        layout.set_text(percent, -1)
+        percent_width, percent_height = layout.get_pixel_size()
+        ctx.move_to(
+            width - POLL_HPADDING - percent_width,
+            bar_y + (bar_height - percent_height) / 2,
+        )
+        PangoCairo.show_layout(ctx, layout)
+
+        # Draw the result count
+        layout.set_ellipsize(Pango.EllipsizeMode.NONE)
+        layout.set_width(-1)
+        layout.set_text(str(answer.numVotes), -1)
+        votes_width, votes_height = layout.get_pixel_size()
+        if votes_width < (bar_x2 - bar_x - 2 * POLL_HPADDING):
+            # Votes fit in the bar
+            ctx.move_to(
+                bar_x + (bar_x2 - bar_x - votes_width) / 2,
+                bar_y + (bar_height - votes_height) / 2,
+            )
+            ctx.set_source_rgb(*POLL_BG)
+            PangoCairo.show_layout(ctx, layout)
+        else:
+            # Votes do not fit in the bar, so put them after
+            ctx.move_to(bar_x2 + POLL_HPADDING, bar_y + (bar_height - votes_height) / 2)
+            ctx.set_source_rgb(*POLL_FG)
+            PangoCairo.show_layout(ctx, layout)