From a3ad37d9ef14f4611a3c271b06fa26d6d3e266b1 Mon Sep 17 00:00:00 2001
From: Matteo Vaccari <vaccari@pobox.com>
Date: Sat, 28 Oct 2023 09:40:14 +0200
Subject: [PATCH] Add line-of-sight restriction on ranged combat!

---
 README.md               | 2 +-
 src/lib/hexlib.js       | 2 +-
 test/lib/hexlib_test.js | 4 ++--
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/README.md b/README.md
index 8ddf45c..6fc5b8f 100644
--- a/README.md
+++ b/README.md
@@ -51,6 +51,7 @@ image to appear.  The parameters are:
 # TODO AI 
 
 - macro-move sampling: avoid duplicate macro-moves in a node's children
+- macro-move sampling: make units not moving an option
 - macro-move sampling: tune the explore/exploit ratio
 - open loop instead of chance nodes
 - implement evasion and line-of-sight rules for ranged combat, to allow the realistic game strategy to emerge
@@ -60,7 +61,6 @@ image to appear.  The parameters are:
 # TODO RULES
 
 - evasion
-- ranged combat line of sight restriction
 - more cards
 - advance after combat
 - cavalry, chariot battle again after advance
diff --git a/src/lib/hexlib.js b/src/lib/hexlib.js
index 8ec4b3d..d0f2aa4 100644
--- a/src/lib/hexlib.js
+++ b/src/lib/hexlib.js
@@ -194,7 +194,7 @@ export function hasLineOfSight(toHex, fromHex, isBlocked = () => false) {
     const distance = fromHex.distance(toHex);
     const step = hex_subtract(toHex, fromHex);
     const stepSize = 1.0 / distance;
-    for (let i = 0; i < distance; i++) {
+    for (let i = 1; i < distance; i++) {
         const stepHex = hex_round(fromHex.q + (step.q * stepSize * i),
             fromHex.r + (step.r * stepSize * i),
             fromHex.s + (step.s * stepSize * i));
diff --git a/test/lib/hexlib_test.js b/test/lib/hexlib_test.js
index 23d4c33..e4603b1 100644
--- a/test/lib/hexlib_test.js
+++ b/test/lib/hexlib_test.js
@@ -61,8 +61,8 @@ describe('line of sight', () => {
         {from: hexOf(0,0), to: hexOf(-1,2), expected: true },
     ].forEach(({from, to, expected}) => {
         test(`Line of sight from ${from} to ${to}: ${expected}`, () => {
-            console.log(`Line of sight from ${from} to ${to}: ${expected}`)
-           expect(hasLineOfSight(to, from)).toBe(expected);
+            const blocked = hex => hex === from || hex === to;
+            expect(hasLineOfSight(to, from)).toBe(expected);
         });
     });