bin: improve the style and add more documentation

And also run rubocop on the CI for good measure.

Signed-off-by: Miquel Sabaté Solà <mssola@mssola.com>

1 files changed, 11 insertions, 1 deletions

diff --git a/bin/rand.rb b/bin/rand.rb
index f627748..b781b6e 100644
--- a/bin/rand.rb
+++ b/bin/rand.rb
@@ -1,5 +1,15 @@
 # frozen_string_literal: true
 
+##
+# Generate a table of 256 bytes of pseudo-random values. These values are
+# constrained with the upper and lower margins of the screen where enemies can
+# appear, and discard certain positions like platforms that can be troublesome
+# on enemy creation. All in all not exactly super pure randomness, but on the
+# other hand this game just needs a bit of randomness.
+#
+# Whenever you update values on background.s, you are supposed to call this
+# script again and replace the values on 'valid_y_rand_table' in prng.s.
+
 # See values on background.s
 UPPER_MARGIN_Y_COORD = 0x1A
 GROUND_Y_COORD = 0xC8 - 32 # NOTE: As in background.s - twice the size of the enemy.
@@ -10,7 +20,7 @@ available = (UPPER_MARGIN_Y_COORD..GROUND_Y_COORD).to_a - (0x58..0x69).to_a - (0
 
 # With this produce the array containing a randomized sample from the
 # 'available' values.
-random_byte_array = Array.new(256) { '$%02X' % available.sample }
+random_byte_array = Array.new(256) { format('$%02X', available.sample) }
 
 # And now print it in the assembler format.
 random_byte_array.each_slice(16) do |row|