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OpenGL OpenGL texture artifacts

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Hi! I am working on a 2D-pixel-art game (this style: http://www.lovepixel.idv.tw/ ). The problem is that my textures are filled with artifacts when OpenGL have generated them, and I don't have an idea how to fix this. The left image is the original texture, and the right is the image applied on a quad in the game engine. artifacts The code I am using to generate the textures are
glGenTextures(1, &mHandle);
glBindTexture(GL_TEXTURE_2D, mHandle);

glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);

glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, loader->getWidth(), loader->getHeight(), 0, GL_RGB, GL_UNSIGNED_BYTE, loader->getData());
Should I use some other glTexParameter's, or what should I try? Thanks for your thoughts! /Klarre

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The banding on the gradient looks like being a precision issue - try changing the GL_RGB to GL_RGB8 to explicitly request 32bit colour rather than leaving the driver to decide. Make sure you're creating your framebuffer at 32bit rather than 16 too (if you don't set it, it'll probably default to the desktop depth).

The blocky artifacts are odd though. If this was 3d I'd say it could be z-fighting, but if thats one big texture then thats not going to be it. It could be some kind of block-based texture compression - are you loading DXT or DDS format textures? Perhaps you've tinkered with something in your computer's 3d settings to force texture compression?

It might be useful if you posted code from the loader class too.

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I had things like that happen to me too when I turned down the image quality settings in my nvidia drivers. All my smooth 2d GUI textures looked like shit.

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Problem solved!

I checked up my driver settings and changed the "Image settings" from "High performance" to "Performance" on my NVIDIA graphics card - the blocky uglyness disappeared!

Thank you guys!

/Klarre

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Quote:
Original post by Klarre
Problem solved!

I checked up my driver settings and changed the "Image settings" from "High performance" to "Performance" on my NVIDIA graphics card - the blocky uglyness disappeared!

Thank you guys!

/Klarre


Yeah, turning it down doesn't really tell you what it does, but it's something I did just because I always have low specs and I just turn off all the bells and whistles to keep things smoother.

I posted the same topic here, and people posted all kinds of things about what I was doing wrong, when I wasn't doing anything wrong at all. Damn driver. I'm wondering what exactly this optimization does to get those artifacts.

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