Remove NMP reduction evaluation scaling

for atomic and losing chess variants.

atomic STC
LLR: 2.96 (-2.94,2.94) [0.00,10.00]
Total: 5957 W: 2213 L: 2054 D: 1690
http://www.variantfishtest.org:6543/tests/view/60106a3b6e23db077dd6623f

atomic LTC
LLR: 2.95 (-2.94,2.94) [0.00,10.00]
Total: 2864 W: 1019 L: 905 D: 940
http://www.variantfishtest.org:6543/tests/view/60109d7b6e23db077dd6624d

giveaway STC
LLR: 2.96 (-2.94,2.94) [0.00,10.00]
Total: 2571 W: 1026 L: 909 D: 636
http://www.variantfishtest.org:6543/tests/view/60106a286e23db077dd6623c

giveaway LTC
LLR: 2.95 (-2.94,2.94) [0.00,10.00]
Total: 4502 W: 1652 L: 1514 D: 1336
http://www.variantfishtest.org:6543/tests/view/60109d1c6e23db077dd66241

diff --git a/src/search.cpp b/src/search.cpp
index 1573f7c..367a132 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -943,7 +943,7 @@ namespace {
         assert(eval - beta >= 0);
 
         // Null move dynamic reduction based on depth and value
-        Depth R = (1015 - 300 * pos.must_capture() - 250 * !pos.checking_permitted() + 85 * depth) / 256 + std::min(int(eval - beta) / (191 + 200 * pos.must_capture() + 200 * pos.blast_on_capture()), 3);
+        Depth R = (1015 - 300 * pos.must_capture() - 250 * !pos.checking_permitted() + 85 * depth) / 256 + std::min(int(eval - beta) / 191, pos.must_capture() || pos.blast_on_capture() ? 0 : 3);
 
         ss->currentMove = MOVE_NULL;
         ss->continuationHistory = &thisThread->continuationHistory[0][0][NO_PIECE][0];