Add axis visualizer script

extras/scripts/axis_visualizer.py

@@ -0,0 +1,77 @@
+"""
+Display a graph that shows axis output values across the range of input values.
+
+Yes, there is a nasty bit of path manipulation to allow importing of joystick_xl
+modules from this folder.  Sorry. :P
+"""
+
+# Adjust the min/max/deadband values to suit your test case.
+min = 5000
+max = 64535
+deadband = 2500
+
+# nasty path manipulation
+import os  # noqa: E402
+import sys  # noqa: E402
+
+sys.path.append(os.path.join(os.path.dirname(__file__), "..", ".."))
+
+try:
+    from joystick_xl.inputs import Axis
+except ImportError:
+    print("*** ERROR: Can't import joystick_xl modules. ***")
+    sys.exit()
+
+try:
+    from matplotlib import pyplot as plt
+except ImportError:
+    print("*** ERROR: matplotlib is required to display graphs. ***")
+
+# readability constants
+AXIS = 0
+OUTPUT = 1
+NODB = 0
+NORMAL = 1
+INVERTED = 2
+
+# generate axis data
+input = [i for i in range(65536)]
+axes = [
+    [Axis(min=min, max=max), []],
+    [Axis(deadband=deadband, min=min, max=max, invert=False), []],
+    [Axis(deadband=deadband, min=min, max=max, invert=True), []],
+]
+for i in input:
+    for a in axes:
+        a[AXIS].source_value = i
+        a[OUTPUT].append(a[AXIS]._update())
+
+# normal axis
+plt.plot(input, axes[NORMAL][OUTPUT], color="blue", zorder=1.0)
+
+# inverted axis
+plt.plot(input, axes[INVERTED][OUTPUT], color="orange", zorder=0.9)
+
+# reference line accounting for min/max but ignoring deadband
+plt.plot(input, axes[NODB][OUTPUT], ":", color="lightgrey", zorder=0.1)
+
+# minimum line
+plt.axvline(x=min, color="lightgrey", linestyle=":", zorder=0.1)
+
+# maximum line
+plt.axvline(x=max, color="lightgrey", linestyle=":", zorder=0.1)
+
+# center point accounting for min/max
+plt.axvline(
+    x=axes[NODB][AXIS]._raw_midpoint, color="lightgrey", linestyle=":", zorder=0.1
+)
+
+# labels and titles
+plt.title("Processed Axis Output over Entire Input Range")
+plt.xlabel("Raw Input Value (16-bit)")
+plt.xticks([0, 8192, 16384, 24576, 32768, 40960, 49152, 57344, 65535])
+plt.ylabel("Processed Axis Value (8-bit)")
+plt.legend(["Normal", "Inverted"])
+
+# draw it!
+plt.show()