Enumerate the map tiles in row order #3641
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Can you please explain what is the motivation behind the change? |
It's conventional to go through arrays in the order that they're stored in memory, because it's often better for the CPU memory cache and therefore faster. Random relevant QA here: https://stackoverflow.com/questions/11148575/why-is-it-worse-to-initialize-a-two-dimensional-array-like-this |
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Sure. The reason why I've asked this is because it wasn't immediately visible to me what was the original layout of arrays affected by the PR (Without carefully reading into the diff and surrounding code; e.g., theoretically, there are cases where optimal physical data orientation is column-wide instead of row-wide). Just a bit more context either here in the PR description or in the code comments section would be great. |
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Most cases where we loop over the map tiles do so in memory order, but a few reversed the nested loops (resulting in enumerating in column order, which is not the order in memory). Fix this.