Add a script to generate palettes from matplotlib colormaps

mpl_colormap_to_pal.py

@@ -0,0 +1,33 @@
+#!/usr/bin/env python3
+
+import argparse
+import importlib
+
+import matplotlib as mpl
+import numpy as np
+
+parser = argparse.ArgumentParser(
+    description="Generate Amrvis palette files from matplotlib colormaps."
+)
+parser.add_argument("cmap", nargs="+", help="the name of a matplotlib colormap")
+parser.add_argument(
+    "--import",
+    action="append",
+    dest="extra_imports",
+    metavar="MODULE",
+    default=[],
+    help="module to import for additional colormaps",
+)
+args = parser.parse_args()
+print(args)
+
+for name in args.extra_imports:
+    importlib.import_module(name)
+
+for cm_name in args.cmap:
+    cmap = mpl.colormaps.get_cmap(cm_name)
+    colors = cmap.resampled(256)(np.linspace(0, 1, 256))
+    data = np.round(colors * (255, 255, 255, 100)).astype(np.uint8).T.reshape(-1)
+    filename = f"{cmap.name}.pal"
+    data.tofile(filename)
+    print(f"wrote palette to {filename}")