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24-bit color sucks

tiamat.tsotech.com

61–70 of 90 posts

Re: 24-bit color sucks

#61
I don't see the gradient switch either.

And having 2GB of VRAM does not imply that you'll need a 268-million pixel display to use it all. In modern games, the vast majority of that VRAM is used by textures (and we need as much of it as we can get!)

Re: 24-bit color sucks

#62

Missing wood for trees. RGB displays are deliberately made to be 'good enough' rather than 'great'. None of them can display whole areas of the visible spectrum [1]. Before taking issue with tiny amounts of visible banding, just maybe it would be better if monitors could actually display a reasonable amount of the visible spectrum... [1] For a reasonable graphic example http://en.wikipedia.org/wiki/File:CIExy1931_srg…

24bit is far from enough to prevent banding, and in many cases it's not just "a tiny amount" either. For example, a css gradient from #333 to #666:

http://i.imgur.com/9xeDT.png?1

It's quite obvious that for a gradient from 0x33 to 0x66 (one component), there are simply not enough distinct values to prevent banding. In this case, the range is 51 different values, for a gradient that's maybe spanning 500-1000 pixels. It really looks quite terrible.

Re: 24-bit color sucks

#63
post #28
post #26

Earlier quoted context omitted.

Not only that, it's such a processor hog it makes my MacBook Air fans whir at full volume. I disabled JavaScript on the site, hoping that would make it behave, and got... no blog, only this: > This blog uses a little JavaScript. Nothing dodgy, though, and nothing hosted at third-party sites. Just some jQuery and animation bits. So please, if you'd be so kind, ask Noscript to call off the hounds. Congratulations, thos…

> which you won't let me turn off In the lower right corner of the site there is the word "normal". Hover over this area and select "stop animation" from the menu that appears. (Not that this excuses any of it. Just saying it's possible.)

Ahahaha. Hover. On a tablet.

(Didn't see any controls whatsoever, but that site happily slowed my FF to a crouch)

And that ignores the issue of argueing for more fidelity while making the argument hard to read.

Re: 24-bit color sucks

#65

I don't see any difference between those two bars, and my eyes are generally pretty good. 24bit is fine. It's <200dpi that has to die.

Most screens aren't able to display reliably 24 bits color anyway. In fact, until recently many cheap LCD screens were able to display a 16 or 20 bits color space.

Re: 24-bit color sucks

#66
Oh wow, the nineties called and they want their grayscale-only AA back... To make a point he conveniently totally forgot to talk about RGB decimation / subpixel rendering. WTF !? Seriously...

If he really thinks that there's only one step between #484848 and #494949 then I'd suggest reading a bit on MS' ClearType and using a magnifier to take a closer look at how Windows or OS X fonts are rendered. Hint: it's not grayscale anti-aliasing.

I honestly don't think that using dithering "because pixels are small" would provide better result than sub-pixel anti-aliasing.

Re: 24-bit color sucks

#67
What problem does 30 bit color depth solve?

The obvious answer (or strawman) might be aesthetics. Yet two bits is sufficient to create art. Each medium has its limitations. Pen and ink, watercolor, clay - why should a computer screen be seen as inherently different?

We tend to view computer art on our own often miscalibrated displays, under variable lighting conditions, and at a variety of resolutions. Computer art is generally mass produced. Yes, it is behind glass, but not in the manner of the MonaLisa.

I'm not saying that "deep color" isn't worthwhile. Only that a coherent case for its practical advantages wasn't made. The problem wasn't obvious on my screen, and I am biased toward content over form.

Re: 24-bit color sucks

#68

I agree. Displays in general suck. The display on the RMBP is a step in the right direction, but there's still a lot of work to be done. Anyone who settles for "good enough" may as well live life like it's the 16th century. It was "good enough" then too. My vision for the future? Specifications that fully exceed the human capacity for discernibility. 2880x1800? Nope, I can still see aliasing (particularly in Terminal…

Huh, don't get me started on image quality and such. Look how people watch constantly 4:3 movies horribly stretched on 16:9 screens. Look how bad the animation is on 99% of bluRay films (to the point of being unbearable) -- action scenes are stuttering and jittering except on the most recent hardware.

Re: 24-bit color sucks

#69

The number of bytes of memory available on GPUs is hardly the biggest issue when considering rendering at more than 8 bits per channel of color precision. Even producing a 30-bit framebuffer (as has been supported for a while on many desktop GPUs) comes at a performance penalty and is incompatible with many pieces of software and hardware. Modern GPUs actually allow 16 bits per channel of precision when rendering, bu…

> Modern GPUs actually allow 16 bits per channel of precision when rendering, but it comes at a significant cost - various features no longer function, memory bandwidth is devoured, etc.

I'm not sure that this is true. It's extremely common for games to render lighting texture maps with HDR render targets. 16 bit-per-channel render targets are often used to accumulate excess light. The excess light gets processed by successful full screen pixel shader passes. These passes generally include blurring and flattening into a normal 8-bit-per-channel texture on the swap chain.

Furthermore, multiple render targets have been common since before the release of the Xbox 360. Deferred shading engines come into and out of popularity on what seems like a biyearly basis depending on what visual style is popular in games currently.

It seems to me that modern hardware is quite capable of greater color range, but the most demanding applications, games, would rather use that extra video RAM and fill rate for storing and processing surface normals, lighting scalars, material properties, etc. Desktop applications always lag behind games dramatically. Hell, browsers are just now starting to see some of the benefits of modern GPUs.

Re: 24-bit color sucks

#70

What problem does 30 bit color depth solve? The obvious answer (or strawman) might be aesthetics. Yet two bits is sufficient to create art. Each medium has its limitations. Pen and ink, watercolor, clay - why should a computer screen be seen as inherently different? We tend to view computer art on our own often miscalibrated displays, under variable lighting conditions, and at a variety of resolutions. Computer art i…

Let's only use two bits then!
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