From 1f9c38b57d764e4316c8c62c9cad901168d49c9c Mon Sep 17 00:00:00 2001
From: TheRedKorsar <korsar962@bk.ru>
Date: Sat, 30 Apr 2022 16:41:31 +0300
Subject: [PATCH] Seamless texture

We can validate near cells through the edge, that will give us seamless texture result
---
 sketch.js | 22 +++++++---------------
 1 file changed, 7 insertions(+), 15 deletions(-)

diff --git a/sketch.js b/sketch.js
index c3a01ac..1448134 100644
--- a/sketch.js
+++ b/sketch.js
@@ -136,45 +136,37 @@ function draw() {
       } else {
         let options = new Array(tiles.length).fill(0).map((x, i) => i);
         // Look up
-        if (j > 0) {
-          let up = grid[i + (j - 1) * DIM];
+          let up = grid[i + ((j + DIM - 1) % DIM) * DIM];
           let validOptions = [];
           for (let option of up.options) {
             let valid = tiles[option].down;
             validOptions = validOptions.concat(valid);
           }
           checkValid(options, validOptions);
-        }
         // Look right
-        if (i < DIM - 1) {
-          let right = grid[i + 1 + j * DIM];
-          let validOptions = [];
+          let right = grid[(i + 1) % DIM + j * DIM];
+          validOptions = [];
           for (let option of right.options) {
             let valid = tiles[option].left;
             validOptions = validOptions.concat(valid);
           }
           checkValid(options, validOptions);
-        }
         // Look down
-        if (j < DIM - 1) {
-          let down = grid[i + (j + 1) * DIM];
-          let validOptions = [];
+          let down = grid[i + ((j + 1) % DIM) * DIM];
+          validOptions = [];
           for (let option of down.options) {
             let valid = tiles[option].up;
             validOptions = validOptions.concat(valid);
           }
           checkValid(options, validOptions);
-        }
         // Look left
-        if (i > 0) {
-          let left = grid[i - 1 + j * DIM];
-          let validOptions = [];
+          let left = grid[((i + DIM - 1) % DIM) + j * DIM];
+          validOptions = [];
           for (let option of left.options) {
             let valid = tiles[option].right;
             validOptions = validOptions.concat(valid);
           }
           checkValid(options, validOptions);
-        }
 
         // I could immediately collapse if only one option left?
         nextGrid[index] = new Cell(options);