step 4: add digital bar level and status gauges

src/dpg_gauges/scales.py

@@ -4,6 +4,7 @@ from __future__ import annotations
 
 import math
 from collections.abc import Sequence
+from typing import Literal
 
 from .exceptions import GaugeConfigError, GaugeValueError
 from .types import GaugeMarker, ThresholdBand
@@ -59,6 +60,29 @@ def fill_fraction(value: float, min_value: float, max_value: float, *, clamp: bo
     return normalize_value(value, min_value, max_value, clamp=clamp)
 
 
+def fill_span(
+    value: float,
+    min_value: float,
+    max_value: float,
+    *,
+    fill_mode: Literal["clamp", "centered"] = "clamp",
+    clamp: bool = True,
+) -> tuple[float, float]:
+    fraction = fill_fraction(value, min_value, max_value, clamp=clamp)
+    if fill_mode == "clamp":
+        return 0.0, fraction
+    zero = fill_fraction(0.0, min_value, max_value, clamp=True)
+    return min(zero, fraction), max(zero, fraction)
+
+
+def normalized_span(
+    start: float, end: float, min_value: float, max_value: float
+) -> tuple[float, float]:
+    first = fill_fraction(start, min_value, max_value, clamp=True)
+    second = fill_fraction(end, min_value, max_value, clamp=True)
+    return min(first, second), max(first, second)
+
+
 def generate_ticks(min_value: float, max_value: float, count: int) -> list[float]:
     validate_range(min_value, max_value)
     if count < 2: