Show * crosstrain marker more often (floatingatoll, #8235)

If the crosstraining-enhanced skill was displayed in the menu for being
trainable, but had less than 1.0 skill levels, the crosstrain-granting
skill would not get the '*' marker (unless the menu was set to show
all).  Now show the marker whenever the menu shows the enhanced skill.

Doing that without duplicating the menu logic from _show_skill in
crosstrain_other required moving crosstrain_other into skill_menu.cc
(which was the only thing that called it).  It could be made static
then, but several utility functions (and a constant) in skills2.cc had
to be made non-static, so perhaps it's a wash.

Also make the same adjustment to antitrain_other, even though currently
that is irrelevant: you must have at least 1.0 skill for antitraining to
have an effect.

1 files changed, 7 insertions, 2 deletions

diff --git a/crawl-ref/source/skills2.h b/crawl-ref/source/skills2.h
index 5b31ecd016..9982b0920a 100644
--- a/crawl-ref/source/skills2.h
+++ b/crawl-ref/source/skills2.h
@@ -11,6 +11,9 @@ const int MAX_SKILL_ORDER = 100;
 #include "enum.h"
 #include "player.h"
 
+// This threshold is in tenths of a skill point.
+const int CROSSTRAIN_THRESHOLD = 1;
+
 struct skill_state
 {
     FixedBitVector<NUM_SKILLS>            can_train;
@@ -68,10 +71,12 @@ float species_apt_factor(skill_type sk, species_type sp = you.species);
 unsigned int skill_exp_needed(int lev, skill_type sk,
                               species_type sp = you.species);
 
+skill_type opposite_skill(skill_type sk);
+bool compare_skills(skill_type sk1, skill_type sk2);
+vector<skill_type> get_crosstrain_skills(skill_type sk);
+
 float crosstrain_bonus(skill_type sk);
-bool crosstrain_other(skill_type sk, bool show_zero);
 bool is_antitrained(skill_type sk);
-bool antitrain_other(skill_type sk, bool show_zero);
 
 int elemental_preference(spell_type spell, int scale = 1);