Poor graphics / Banding issues
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When I'm running my program, I get an image that seems to have severe banding issues. That is, the transition between colors isn't smooth, but rather there appear to be bands. I suppose my problem is coming from a bit-depth configuration too low (8 bits).
How to configure with QT and OpenGl better floating-point textures and get a better rendering? ?
Thanks !
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@Francky033 said in Poor graphics / Banding issues:
When I'm running my program
you should be more specific what your application consists of.
What are you displaying and how specifically.
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Yes... I'm sorry...
It's a planetarium and I'm trying to get a good quality sky gradient on the horizon. I use Qt 5.10 and opengl 3.0.
I created a vertical tube that has a transparency of 0.0 at its top and 1.0 at its base that allows to get this gradient. But the result is mediocre, with irregularities appearing in the colors...
I suppose that an 8-bit buffer of each color doesn't allow good quality gradients...
I tried to increase the size of the buffers of each color.from that
format. setBlueBufferSize (8);
format. setRedBufferSize (8);
format. setGreenBufferSize (8);
to :
format. setBlueBufferSize (16);
format. setRedBufferSize (16);
format. setGreenBufferSize (16);but without success..
How can we improve things?
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@Francky033
so that means you are using QGLWidget or QML?
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I'm using a QOpenGLWidget...
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Hi
Not into openGl so much but i wondering if
8bit openGl means palette based ?
(256 colors available)
In that case gradients will look awful. :)what are you using 8bit ?
(for retro look games, normally you would alter the assets to
use a common 256 color palette and then just render that)
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No, I'm talking about 8 bits for each color channel i. e. for each pixel channel r, g, b, a (8x4 = 32 bits)
Use Bayer's matrix maybe?
http://www.anisopteragames.com/how-to-fix-color-banding-with-dithering/
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@Francky033
Ah, that way. The BM methods sounds worth trying at least to see how
big effect it will have.
