Visual issue with 1.17.pr and 1.17.pr2

    Sorry if this is an already known issue or a non-issue.

    I have an issue where the "texture" of the panorama along what appears to be the edges the cubefaces looks different from the rest of the panorama at wide FOV. The issue is present in the WebGL version of krpano in Chrome 32.0 and Firefox 26.0 but not in IE11.0. Further more it is visible in almost all panoramas. I have shown the panorama to several people and nobody notices the issue until told. I have tried to outline the issue in this screenshot:

    The panorama I used above is this http://panographica.dk/panoramas/tour…cene_panorama07

    Best regards,

    Obel

    Edited once, last by obel (January 13, 2014 at 3:30 PM).

    Hi,

    the reason therefore is 'mip-mapping'.

    With mip-mapping WebGL will automatically use down-scaled versions of the image for smaller renderings. This avoids aliasing. But there is a limitation - only images (tiles) that have a 'power-of-two' size like 512(=2^9), 1024(=2^10), 2048(=2^11) can be mip-mapped.

    In IE11 there is no visual change because the IE11 WebGL implementation doesn't fully support mip-mapping.

    See also here:
    https://krpano.com/docu/xml/#display.mipmapping

    In krpano version 1.17.pr2 currently only the mipmapping settings 'auto' and 'none' are implemented. The setting 'force', which will internally enlarge the tile image to fit into the next available 'power-of-two' size, will come with future versions.

    To have an uniform rendering you could disable mip-mapping at all - e.g. with:

    Code
    <display mipmapping="none" />

    Here your example with that settings:
    http://panographica.dk/panoramas/tour…mipmapping=none

    Best regards,
    Klaus

    Hi again,

    Let me get this straight. It's the incomplete mipmapping support in IE that causes the panorama to flicker or appear "nervous" when I pan slowly. It's the same in FF and Chrome for tiles that are not power-of-two in resolution.

    So, would it be advantageous for me to assure that my tiles are all power-of-two in resolution?

    Best regards,

    Obel

    Hi,

    yes, if you want to take advantage of the mip-mapping, try to size the levels to be dividable into power-of-two tile-sizes (e.g. partials tiles like 128x512 or 64x512 are also working).

    Btw - I'm already planing also an option for letting the krpano tools do that automatically.

    Best regards,
    Klaus

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