fix(vl53l1x): Optimize radar math, fix boundaries

Author: Kaanoz-en

lib/vl53l1x/examples/radar_screen.py

@@ -30,18 +30,16 @@
         # Clear the display frame buffer
         display.fill(0)
 
-        # Clamp distance to maximum range to avoid negative ratios
+        # Clamp distance to maximum range and compute integer proximity
         clamped_dist = max(0, min(distance, MAX_DISTANCE_MM))
+        proximity = MAX_DISTANCE_MM - clamped_dist
 
-        # Calculate ratio (1.0 = extremely close, 0.0 = MAX_DISTANCE_MM or further)
-        ratio = 1.0 - (clamped_dist / MAX_DISTANCE_MM)
-
-        # Map ratio to a maximum width of 80 pixels (to fit the round screen) and brightness (15 levels)
-        bar_width = int(80 * ratio)
-        brightness = int(15 * ratio)
+        # Map proximity linearly to a maximum width of 80 pixels and brightness (15 levels) using integer math
+        bar_width = (80 * proximity) // MAX_DISTANCE_MM
+        brightness = (15 * proximity) // MAX_DISTANCE_MM
 
         # If the object is within the detection range, ensure minimum visibility
-        if distance < MAX_DISTANCE_MM:
+        if distance <= MAX_DISTANCE_MM:
             bar_width = max(1, bar_width)
             brightness = max(1, brightness)