Expand mutate() to account for mutations as god gifts, and make Xom use

them, so that he respects the full mutation resistance mutation, as well 
as the limitations on how much players can be covered in scales, etc.


git-svn-id: https://crawl-ref.svn.sourceforge.net/svnroot/crawl-ref/trunk@4666 c06c8d41-db1a-0410-9941-cceddc491573

1 files changed, 30 insertions, 22 deletions

diff --git a/crawl-ref/source/mutation.cc b/crawl-ref/source/mutation.cc
index 2630ea28db..b4a1debbea 100644
--- a/crawl-ref/source/mutation.cc
+++ b/crawl-ref/source/mutation.cc
@@ -1649,7 +1649,8 @@ static mutation_type get_random_mutation(bool prefer_good,
 }
 
 bool mutate(mutation_type which_mutation, bool failMsg,
-            bool force_mutation, bool demonspawn)
+            bool force_mutation, bool god_gift,
+            bool demonspawn)
 {
     if (demonspawn)
         force_mutation = true;
@@ -1693,8 +1694,17 @@ bool mutate(mutation_type which_mutation, bool failMsg,
     // except for demonspawn (or other permamutations) in lichform -- haranp
     if (rotting && !demonspawn)
     {
-        if (wearing_amulet(AMU_RESIST_MUTATION) ? one_chance_in(10)
-                                                : !one_chance_in(3))
+        // Temporary resistance can be overridden by a god gift.
+        if ((wearing_amulet(AMU_RESIST_MUTATION) ? !one_chance_in(10)
+                                                 : one_chance_in(3))
+            && !god_gift)
+        {
+            if (failMsg)
+                mpr("You feel odd for a moment.", MSGCH_MUTATION);
+
+            return (false);
+        }
+        else
         {
             mpr( "Your body decomposes!", MSGCH_MUTATION );
 
@@ -1709,17 +1719,14 @@ bool mutate(mutation_type which_mutation, bool failMsg,
             xom_is_stimulated(64);
             return (true);
         }
-
-        if (failMsg)
-            mpr("You feel odd for a moment.", MSGCH_MUTATION);
-
-        return (false);
     }
 
     if (!force_mutation)
     {
-        if (wearing_amulet(AMU_RESIST_MUTATION) && !one_chance_in(10)
-            || you.religion == GOD_ZIN && you.piety > random2(MAX_PIETY)
+        // Temporary resistance can be overridden by a god gift.
+        if (((wearing_amulet(AMU_RESIST_MUTATION) && !one_chance_in(10))
+            || (you.religion == GOD_ZIN && you.piety > random2(MAX_PIETY))
+                && !god_gift)
             || player_mutation_level(MUT_MUTATION_RESISTANCE) == 3
             || player_mutation_level(MUT_MUTATION_RESISTANCE)
                && !one_chance_in(3))
@@ -1778,7 +1785,6 @@ bool mutate(mutation_type which_mutation, bool failMsg,
     if (you.mutation[mutat] > 13 && !force_mutation)
         return false;
 
-    // These can be forced by demonspawn
     if ((mutat == MUT_TOUGH_SKIN || mutat == MUT_SHAGGY_FUR
             || mutat >= MUT_GREEN_SCALES && mutat <= MUT_BONEY_PLATES
             || mutat >= MUT_RED_SCALES && mutat <= MUT_PATTERNED_SCALES)
@@ -1805,9 +1811,10 @@ bool mutate(mutation_type which_mutation, bool failMsg,
         }
     }
 
-    // This one can be forced by demonspawn
+    // This one can be forced by demonspawn or a god gift
     if (mutat == MUT_REGENERATION
-        && you.mutation[MUT_SLOW_METABOLISM] > 0 && !force_mutation)
+        && you.mutation[MUT_SLOW_METABOLISM] > 0 && !god_gift
+        && !force_mutation)
     {
         return false;           // if you have a slow metabolism, no regen
     }
@@ -1815,9 +1822,10 @@ bool mutate(mutation_type which_mutation, bool failMsg,
     if (mutat == MUT_SLOW_METABOLISM && you.mutation[MUT_REGENERATION] > 0)
         return false;           // if you have regen, no slow metabolism
 
-    // This one can be forced by demonspawn
+    // This one can be forced by demonspawn or a god gift
     if (mutat == MUT_ACUTE_VISION
-        && you.mutation[MUT_BLURRY_VISION] > 0 && !force_mutation)
+        && you.mutation[MUT_BLURRY_VISION] > 0 && !god_gift
+        && !force_mutation)
     {
         return false;
     }
@@ -1937,8 +1945,8 @@ bool mutate(mutation_type which_mutation, bool failMsg,
     case MUT_REGENERATION:
         if (you.mutation[MUT_SLOW_METABOLISM] > 0)
         {
-            // Should only get here from demonspawn, where our innate
-            // ability will clear away the counter-mutation.
+            // Should only get here from demonspawn or a god gift, where
+            // our innate ability will clear away the counter-mutation.
             while (delete_mutation(MUT_SLOW_METABOLISM))
                 ;
         }
@@ -1948,8 +1956,8 @@ bool mutate(mutation_type which_mutation, bool failMsg,
     case MUT_ACUTE_VISION:
         if (you.mutation[MUT_BLURRY_VISION] > 0)
         {
-            // Should only get here from demonspawn, where our innate
-            // ability will clear away the counter-mutation.
+            // Should only get here from demonspawn or a god gift, where
+            // our innate ability will clear away the counter-mutation.
             while (delete_mutation(MUT_BLURRY_VISION))
                 ;
         }
@@ -2747,13 +2755,13 @@ bool perma_mutate(mutation_type which_mut, int how_much)
     how_much = std::min(static_cast<short>(how_much),
                         mutation_defs[which_mut].levels);
 
-    if (mutate(which_mut, false, true, true))
+    if (mutate(which_mut, false, true, false, true))
         levels++;
 
-    if (how_much >= 2 && mutate(which_mut, false, true, true))
+    if (how_much >= 2 && mutate(which_mut, false, true, false, true))
         levels++;
 
-    if (how_much >= 3 && mutate(which_mut, false, true, true))
+    if (how_much >= 3 && mutate(which_mut, false, true, false, true))
         levels++;
 
     you.demon_pow[which_mut] = levels;