Author Topic: Mipmap creates black texture?  (Read 2188 times)

Offline Irony

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Mipmap creates black texture?
« on: February 09, 2014, 10:38:32 pm »
I did setMipmap(true) after loading a texture. Strangely, it turned out black then. I don't get this - isn't mipmapping turned on by default anyway?

Offline EgonOlsen

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Re: Mipmap creates black texture?
« Reply #1 on: February 09, 2014, 11:40:42 pm »
Yes, it's true by default. I don't see why it should create a black texture. Changing the mipmap setting does trigger a new texture upload, but that shouldn't matter if you are dping this right after creating the texture. Make sure to use the latest release, because it changes the default way in which mipmaps are being created. Also make sure that you aren't using a texture that's not square when you are in OpenGL ES 2.0 mode.

Offline Irony

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Re: Mipmap creates black texture?
« Reply #2 on: February 10, 2014, 09:58:41 am »
The black textures are actually non-square. Will try if changing that helps.
But, I am using the latest version and call setMipmap right after loading, so it's still a mystery anyway...

By the way, do you know of any way to detect if a device cannot display non-square, so I can add square ones as a fallback? I'd prefer not to make all textures square per default, e.g. with planet textures that would be very impractical.
And can the blackness also happen to textures that are only used for blitting?

Offline EgonOlsen

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Re: Mipmap creates black texture?
« Reply #3 on: February 10, 2014, 12:32:29 pm »
That black texture issue is out of the scope of the engine and not limited to any kind texture usage. The problem is that for ES 2.0, there seems to be a lack of definition on how to handle these textures, so the gpu/driver implementation is free to screw it up.
From my experience, it's safe to use textures where width>height but width<height will cause problems (or maybe it's the other way round...i don't remember exactly ATM).

Offline Irony

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Re: Mipmap creates black texture?
« Reply #4 on: February 10, 2014, 12:43:50 pm »
Thanks Egon. I only have width>=height, and I tested it on devices with a nice bandwidth of the big GPUs brands. It always worked, with the exception of this weird case on the top. So I guess it should be pretty safe. The game won't run on old or exotic devices anyway.