From 0f3c2f7cd4c59e1eee6c44d800e266b57e2ec33f Mon Sep 17 00:00:00 2001 From: Simon Tatham Date: Mon, 29 Mar 2021 20:50:28 +0100 Subject: [PATCH] Filling grid gen: slightly randomise neighbour selection. This is another modification to the same piece of code as the previous commit. Previously, a square with a neighbour in a same-sized region was fixed by choosing a neighbour to merge it with that was part of the smallest region. Now, it's _usually_ that, but sometimes it can be a larger neighbour instead. Partly, I hope this might remove a potential source of regularity in the random grids. But mostly, it prevents the grid generator from hanging completely on 2x2 grids (e.g. if you gave "2x2#12345" in the previous state of the code), because with the previous 'always minimal' rule, the generator would merge together two squares of the 2x2 grid, then the other two, and then (due to maxsize==3) it would have no merge remaining to clear the final error. Now, every so often, it will take the unusual option of making a size-3 region instead, which allows game generation to succeed. --- filling.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/filling.c b/filling.c index ffa3ab1..06f6982 100644 --- a/filling.c +++ b/filling.c @@ -434,7 +434,7 @@ retry: /* find the smallest neighbour to merge with, which * wouldn't make the region too large. (This is * guaranteed by the initial value of `min'.) */ - if (neighbour_size < min) { + if (neighbour_size < min && random_upto(rs, 10)) { min = neighbour_size; merge = neighbour; }