Add treemap support in lieu of pie charts

README.md

@@ -1,6 +1,6 @@
 # A native plotting widget for Textual apps
 
-[Textual](https://www.textualize.io/) is an excellent Python framework for building applications in the terminal, or on the web. This library provides a plot widget which your app can use to plot all kinds of quantitative data. So, no pie charts, sorry. The widget support scatter plots and line plots, and can also draw using _high-resolution_ characters like unicode half blocks, quadrants and 8-dot Braille characters. It may still be apparent that these are drawn using characters that take up a full block in the terminal, especially when plot series overlap. However, the use of these characters can reduce the line thickness and improve the resolution tremendously.
+[Textual](https://www.textualize.io/) is an excellent Python framework for building applications in the terminal, or on the web. This library provides a plot widget which your app can use to plot all kinds of quantitative data. So, no pie charts, sorry, but we do have a treemap! The widget support scatter plots and line plots, and can also draw using _high-resolution_ characters like unicode half blocks, quadrants and 8-dot Braille characters. It may still be apparent that these are drawn using characters that take up a full block in the terminal, especially when plot series overlap. However, the use of these characters can reduce the line thickness and improve the resolution tremendously.
 
 ## Screenshots
 

pyproject.toml

@@ -8,7 +8,9 @@ license = "MIT"
 license-files = ["LICENSE"]
 requires-python = ">=3.10"
 dependencies = [
+    "distinctipy>=1.3.0",
     "numpy>=2.2.1",
+    "squarify>=0.4.3",
     "textual>=1.0.0",
     "textual-hires-canvas>=0.14.0",
 ]

src/textual_plot/__init__.py

@@ -3,7 +3,7 @@
     DurationFormatter,
     NumericAxisFormatter,
 )
-from textual_plot.plot_widget import HiResMode, LegendLocation, PlotWidget
+from textual_plot.plot_widget import HiResMode, LegendLocation, PlotWidget, ValueDisplay
 
 __all__ = [
     "AxisFormatter",
@@ -12,4 +12,5 @@
     "LegendLocation",
     "NumericAxisFormatter",
     "PlotWidget",
+    "ValueDisplay",
 ]

src/textual_plot/color_utils.py

@@ -0,0 +1,46 @@
+"""Color utilities for treemap and plot styling."""
+
+from __future__ import annotations
+
+import colorsys
+import re
+
+import distinctipy
+
+
+def parse_style_to_rgb(style: str) -> tuple[float, float, float] | None:
+    """Parse rgb(r,g,b) style string to (r,g,b) tuple in 0-1 range."""
+    m = re.match(r"rgb\s*\(\s*(\d+)\s*,\s*(\d+)\s*,\s*(\d+)\s*\)", style, re.I)
+    if m:
+        return (int(m.group(1)) / 255, int(m.group(2)) / 255, int(m.group(3)) / 255)
+    return None
+
+
+def adjust_luminance(
+    rgb: tuple[float, float, float], factor: float
+) -> tuple[float, float, float]:
+    """Adjust luminance of RGB (0-1) by factor. factor>1 lightens, factor<1 darkens."""
+    h, lightness, s = colorsys.rgb_to_hls(rgb[0], rgb[1], rgb[2])
+    lightness = max(0, min(1, lightness * factor))
+    return colorsys.hls_to_rgb(h, lightness, s)
+
+
+def tint_with_hue(
+    child_rgb: tuple[float, float, float],
+    parent_rgb: tuple[float, float, float],
+) -> tuple[float, float, float]:
+    """Apply parent's hue to child color; keep child's saturation and value for distinction."""
+    ph, ps, pv = colorsys.rgb_to_hsv(parent_rgb[0], parent_rgb[1], parent_rgb[2])
+    ch, cs, cv = colorsys.rgb_to_hsv(child_rgb[0], child_rgb[1], child_rgb[2])
+    r, g, b = colorsys.hsv_to_rgb(ph, cs, cv)
+    return (r, g, b)
+
+
+def rgb_too_close(a: tuple[float, float, float], b: tuple[float, float, float]) -> bool:
+    """True if a and b are too similar (perceptual distance)."""
+    return distinctipy.color_distance(a, b) < 0.02
+
+
+def rgb_style(rgb: tuple[float, float, float]) -> str:
+    """Convert (r,g,b) 0-1 to rgb(r,g,b) style string."""
+    return f"rgb({int(rgb[0] * 255)},{int(rgb[1] * 255)},{int(rgb[2] * 255)})"

src/textual_plot/demo.py

@@ -326,6 +326,117 @@ def action_cycle_hires_mode(self) -> None:
         self.plot()
 
 
+class TreemapPlot(Container):
+    BINDINGS = [("h", "cycle_hires_mode", "HiRes")]
+
+    _hires_mode = itertools.cycle([None, HiResMode.BRAILLE])
+    hires_mode = next(_hires_mode)
+
+    def compose(self) -> ComposeResult:
+        yield PlotWidget()
+
+    def on_mount(self) -> None:
+        self.plot()
+
+    def plot(self) -> None:
+        plot = self.query_one(PlotWidget)
+        plot.clear()
+
+        values = [500, 433, 280, 195, 165, 120, 95, 78, 62, 48, 35, 28, 25, 18, 12]
+        labels = [
+            "Electronics",
+            "Clothing",
+            "Home",
+            "Sports",
+            "Books",
+            "Toys",
+            "Garden",
+            "Auto",
+            "Health",
+            "Beauty",
+            "Office",
+            "Food",
+            "Pets",
+            "Music",
+            "Art",
+        ]
+        plot.treemap(
+            values,
+            labels=labels,
+            padding=1,
+            hires_mode=self.hires_mode,
+        )
+        plot.show_legend()
+
+    def action_cycle_hires_mode(self) -> None:
+        self.hires_mode = next(self._hires_mode)
+        self.plot()
+
+
+class NestedTreemapPlot(Container):
+    """Nested treemap: click to zoom in, Escape to zoom out, arrows to select."""
+
+    BINDINGS = [("h", "cycle_hires_mode", "HiRes")]
+
+    _hires_mode = itertools.cycle([None, HiResMode.BRAILLE])
+    hires_mode = next(_hires_mode)
+
+    def compose(self) -> ComposeResult:
+        yield PlotWidget()
+
+    def on_mount(self) -> None:
+        self.plot()
+
+    def plot(self) -> None:
+        plot = self.query_one(PlotWidget)
+        plot.clear()
+        # Nested: show_nested=True draws full hierarchy with luminance variance
+        plot.treemap(
+            [
+                {
+                    "label": "Electronics",
+                    "children": [
+                        {
+                            "label": "Phones",
+                            "children": [
+                                {"label": "iPhone", "value": 55},
+                                {"label": "Android", "value": 35},
+                                {"label": "Other", "value": 10},
+                            ],
+                        },
+                        {"label": "Laptops", "value": 50},
+                        {"label": "Tablets", "value": 25},
+                        {"label": "Accessories", "value": 25},
+                    ],
+                },
+                {
+                    "label": "Clothing",
+                    "children": [
+                        {"label": "Shirts", "value": 80},
+                        {"label": "Pants", "value": 60},
+                        {"label": "Shoes", "value": 40},
+                    ],
+                },
+                {
+                    "label": "Home",
+                    "children": [
+                        {"label": "Furniture", "value": 90},
+                        {"label": "Decor", "value": 45},
+                        {"label": "Kitchen", "value": 30},
+                    ],
+                },
+            ],
+            padding=1,
+            hires_mode=self.hires_mode,
+            show_nested=True,
+        )
+        plot.show_legend()
+
+    def action_cycle_hires_mode(self) -> None:
+        self.hires_mode = next(self._hires_mode)
+        self.plot()
+
+
 class DemoApp(App[None]):
     AUTO_FOCUS = "SinePlot > PlotWidget"
 
@@ -350,6 +461,10 @@ def compose(self) -> ComposeResult:
                 yield ErrorBarPlot()
             with TabPane("Bar plot", id="barplot"):
                 yield BarPlot()
+            with TabPane("Treemap", id="treemap"):
+                yield TreemapPlot()
+            with TabPane("Nested Treemap", id="nested_treemap"):
+                yield NestedTreemapPlot()
 
     def on_mount(self) -> None:
         self.theme = "tokyo-night"