Dist: update script to make Steam icon sets

misc/scripts/make_icons.sh

@@ -1,5 +1,24 @@
-convert -resize 32x32 ../../icon.svg icon32.ico
-convert -resize 32x32 ../../icon.svg icon32.icns
-for s in 16 24 32 64 96 128 256; do convert -resize ${s}x$s ../../icon.svg icon$s.png; done
-zip icons.zip icon*.png
-rm icon*.png
+# Generate .ico, .icns and .zip set of icons for Steam
+
+# Make icons with transparent backgrounds and all sizes
+for s in 16 24 32 48 64 128 256 512 1024; do
+  convert -resize ${s}x$s -antialias \
+          -background transparent \
+          ../../icon.svg icon$s.png
+done
+
+# 16px tga file for library
+convert icon16.png icon16.tga
+
+# zip for Linux
+zip godot-icons.zip icon*.png
+
+# ico for Windows
+# Not including biggest ones or it blows up in size
+icotool -c -o godot-icon.ico icon{16,24,32,48,64,128,256}.png
+
+# icns for macOS
+# Only some sizes: http://iconhandbook.co.uk/reference/chart/osx/
+png2icns godot-icon.icns icon{16,32,128,256,512,1024}.png
+
+rm -f icon*.png