Aha! The answer was mipmapping,

#5
Well I spent most of the afternoon looking into this.

It seems that Som doesn't actually have mipmaps for every texture. The ones it does have are presumably embedded in the files (most likely .txr format) which I presumed because generating mipmaps at runtime for paletted images would be impractical. MDL based graphics never have mipmaps.

The mipmaps it does have seem to be really shitty. Or at least under DX7 and D3D9 the roofs in DD go from a very dense texture to a total bloom in one LOD with a sharp transition between the two. It seems that mipmaps are more likely to appear in newer user generated objects. At any rate, Som appears to be really shooting itself in the foot in the mipmap dept, so I intend to see what happens if they are short circuited / generated on the fly for it.

I think the reason I was seeing drivers returning errors when Som looks for mipmaps is because Som just blindly looks for mipmaps even when it did not request any. I don't think there is ever any auto generation by DX7 drivers (unless you turn that on in your display settings)

It was a good lead as to what's wrong with the editors. I have to backpedal a little on why exactly the mipmaps are boogered in the editors. I think only the assets with mipmaps might look bad under XP. Somehow the mipmaps must be requested but never filled. Perhaps it was a bug that slipped by From' because the software device implementation at the time did not do mipmapping.

I was also a little confused about how mipmaps were requested under DirectDraw. It seems like that was never clearly documented even at the the time.
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Aha! The answer was mipmapping, - by HolyDiver - 2010-08-19, 07:06 PM
Re: Aha! The answer was mipmapping, - by HolyDiver - 2010-08-20, 04:01 AM



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