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Do compressed textures, reduce memory size as well? or only hdd size?

Discussion in 'General Graphics' started by mailfromthewilds, May 16, 2021.

  1. mailfromthewilds

    mailfromthewilds

    Joined:
    Jan 31, 2020
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    1. i dont actually care for hdd size

    2. im about to add lot of heavy textures to my game and it may dramatically increase memory

    3. how texture compression works?

    4. does compression reduce ONLY disk size or also MEMORY size? and by how much in %?

    5. does crunch work in same manner? (crunch is additional compressing mechanism as far as i understand, on top of standard one)
     
    mailfromthewilds, May 16, 2021
    #1

  2. AljoshaD

    AljoshaD

    Unity Technologies

    Joined:
    May 27, 2019
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    Compressed textures will be stored in a block compressed format (BC/ETC/ASTC/..) on disk and in memory. This means that using compression reduces memory usage, typically by 4x.

    Crunch will compress the block compressed format further on disk. This only reduces the size on disk. When a texture is loaded, the crunched data is decompressed to a block format before uploading to video memory. So in video memory the texture is still compressed but it is larger than the crunch compressed data on disk.
     
    AljoshaD, May 17, 2021
    #2
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  3. mailfromthewilds

    mailfromthewilds

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    okay i see thanks
    what about GPU usage with compressed textures (non-crunch compression)? is it higher with compressed textures, or lower?
     
    mailfromthewilds, May 24, 2021
    #3

  4. cholleme

    cholleme

    Unity Technologies

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    Apr 23, 2019
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    - Gpu memory usage will be lower with compressed textures
    - Gpu rendering performance will be identical (if not better due to the reduced bandwith requirements of smaller textures and the texture cache being able to contain more texels).

    In general if you can live with the quality reduction of compressed textures they are a good idea to enable.
     
    cholleme, May 27, 2021
    #4