The large size of these maps and their inclusion in the matchmakers is the main reason I decided not to implement the client feature that would require people to download all the maps before joining a queue. The reason for this is that if someone has a slow internet connection or the download of this map freezes which I have gotten reports of then that would effectively stop these players from being able to use the matchmaker. This was not a tradeoff I was willing to make.
Your opinion about maps with map-wide assets
I wouldn't mind a button to download the maps so that both options are available. You could include a warning that on slow internet connections it will not be worth it or something. But I suspect some people would happily leave their client open for a while to grab the maps so that they don't have to wait when they actually want to play.
Former Board Member - March 2021 - March 2022
A button is planned eventually just need to figure out best place in the ui. And it isn't super high priority since once can just open up the map list.
350mb are a real problem for those of us with datacaps. I wonder how much that could be brought down with some lossy compression without losing too much detail.
Most of the size is in the decals which the game only accepts .dds of as far as I am aware so not sure what kinds of compression you could accept there.
Can the maps themselves be compressed and then expanded on the client end?
Former Board Member - March 2021 - March 2022
What I mean is that everything is zipped isn’t it? So perhaps you can optimize the dds file so that it will compress better when deflated. Something like taking all values that are very close to eachother but not quite the same and turning them all into exactly the same value so that the compression algorithm can do its thing.
@furyritchie said in Your opinion about maps with map-wide assets:
Can the maps themselves be compressed and then expanded on the client end?
They already are compressed as zip files
If those decals don't matter for gameplay, is it possible for one player to play without the decals while the other does?
In that case, make a normal and high res version of each map where the latter has no or small size decals.
Automatcher only ever downloads normal versions. With a button you can download all high res maps at once.
@valki said in Your opinion about maps with map-wide assets:
If those decals don't matter for gameplay, is it possible for one player to play without the decals while the other does?
In that case, make a normal and high res version of each map where the latter has no or small size decals.
Automatcher only ever downloads normal versions. With a button you can download all high res maps at once.
This was a potential solution I was thinking of too. I provide the maps in the vault with low-quality assets and you can manually replace them with high-quality assets. You could even go up to 16K per texture (that is 300mb / texture) and Supreme Commander would bite, looks brilliant.
A work of art is never finished, merely abandoned
@sheikah Are they compressed, or stored as a zip folder? I recall windows having an 'add to zip' which is essentially just the map in a file, with no compression.
When I use 7zip on Kaali I get these results:
- unzipped: 258 mb
- zipped: 158 mb
- 7z: 130 mb
Regardless, it remains quite big 
. I would not know how to optimize the DDS for enflation / deflation. The format itself is quite compressed already. Storing them in another format (say .png) and turning them into a DDS file on the client isn't viable either - that requires memory and may just take longer than the download.
A work of art is never finished, merely abandoned
I've updated the original post to contain imagery of some of the maps as requested. I hope to hear more opinions to determine an approach to take 
A work of art is never finished, merely abandoned
@jip factor 2 of comressions doesn't seem too bad. I was hoping that the compression in used for .dds files was variable. But it seems to use only fixed settings.
https://en.wikipedia.org/wiki/S3_Texture_Compression
I don't really know a lot about the subject. The DXT1 version is the most efficient if you don't need an alpha channel. The DXT2-5 reserve a lot of room for the alpha channel. Have you tried this compression? I wasn't able to check if the .dds was already compressed.
Your full map decals use the alpha channel. So DXT3 would need to be used, but still a significant compression. If you were able to not need the alpha channel on your main decal you could even get down to rhoughly 1/3rd.
Haven't tested it yet but I assume FA should be able to handle those files.
Back on topic: Most people don't download the maps before queuing. This results in subjectively half of the tmm games not launching at the start of the pool rotation. Later on in the month it gets better. I would put that auto downloader at a higher priority.
@harzer99
I cannot produce the same results. Using dxt1 turns one of the decals from ~22mb to ~11mb, and DXT3 appears to have no impact on the file size. What tool did you use to generate those files? I used Photoshop with the Nvidia DDS plugin and ImageMagick - both have similar results.
(note: these assets are 4k as they are used during production. Final would be 8k and ~4x the file size)
edit: the game does appear to support the format - so please do inform how you made them
A work of art is never finished, merely abandoned
@jip I used gimp with the DDS plugin. https://code.google.com/archive/p/gimp-dds/downloads
@Sheikah I am not sure if I agree with your reasoning, for me it seems that most issues come from the fact that people don't have a map downloaded and then they take too long to download it when a match is found. Forcing a player to download all of the maps would solve this issue and you can treat the map downloads as something like a monthly update that you need to get in order to play. Considering that 1/4 of the maps stay the same in between rotations and the map pools for lower rated people are small it would be <400 MB which I don't think is unreasonable these days. Another problem it would fix would be the possibility to dodge certain maps on 1vs1 and TMM because you can just cancel the download of the map you don't want to play and re queue.
@Tagada The issue is that for some subset of players the download takes so long and also consistently fails. So forcing them to have to download the map beforehand would effectively lock them out of the matchmaker.
Well, if it takes long then it doesn't matter if they will need to download the map before queuing or after they've found a match. With the first option at least it doesn't give the impression that the matching doesn't work for players and it also doesn't harm other players. As for not being able to download the maps at all then I suppose you could add a note that if the map download fails then you can go into map list and download the map manually? If a player isn't able to download the maps in any way then they can't play the queue anyways right? If you would allow the players to play only on the maps they can download you will harm the accuracy of the ladder rating as well.
I fail to see how forcing an upfront download will harm any user experience, it makes sure everything should work before letting you play and it also allows you to download the maps when you are away from a PC if you have slow internet connection so that you no longer need to worry that the other person will cancel a match because you are taking so long to download the maps.