antialias

Blitz3D Forums/Blitz3D Programming/antialias

Jerome Squalor(Posted 2008) [#1]
hello
im always seeing posts on the forum about antialias and i have a question,
what is it?


Stevie G(Posted 2008) [#2]
...


nawi(Posted 2008) [#3]


It's broken in Blitz3D though.


Jerome Squalor(Posted 2008) [#4]
so it kinda just blends pixels that are next to each other..


Gabriel(Posted 2008) [#5]
In practice, antialiasing is often a synonym for supersampling.Supersampling means that the image is rendered at a higher resolution and then a number of samples ( pixel reads ) are taken from the higher resolution image to actually draw the lower resolution image. The end result is the sort of pixel blending effect that you refer to. There are other ways to antialias, and I do believe that the Blitz3D broken implementation does do it a different way,.

And yes, in Blitz3D, it's broken.


Jerome Squalor(Posted 2008) [#6]
how and why is it broken? can't someone 'fix' it??


Gabriel(Posted 2008) [#7]
On the majority of modern videocards, it doesn't do anything. On a handful of videocards it does something odd like enable it when you try to disable and vice versa.

I first requested that someone fix it about four years ago, maybe more, and it was just ignored over and over. More recently, it was being discussed again and Skidracer said it wasn't possible. Someone offered a solution which he said worked across the board, and then there was no further word from BRL on whether that was, in fact, a valid solution or not.

In short, I wouldn't get your hopes up about it being fixed.


Zethrax(Posted 2008) [#8]
There's been some discussion on the subject of antialising on these forums in the past, where a few people have said that setting a higher screen resolution is more hardware efficient than using antialiasing. Whether that's true or not, I don't know.


QuickSilva(Posted 2008) [#9]
I`d rather BRL would just remove commands that aren`t working completely. It seems silly to leave things that are broken in an otherwise very stable product like B3D.

Jason.


Jerome Squalor(Posted 2008) [#10]
what is the point of using antialias? for what purpose would someone want that effect?


bytecode77(Posted 2008) [#11]
don't confuse "anti-alias" with "blur"


_33(Posted 2008) [#12]
Antialias is absolutely not an effect. first of all, we're talking about FSAA (Full Screen Anti-Alias). The point of using it is that it will blend pixels in a way that you won't see any jaggies when, for example you have a high contrast between 2 objects. If you don't use FSAA, you will see jaggies (or jagged edges).

If you really need to know more, I suggest to look at ANY graphics card review that talks about FSAA and look at the pretty pictures. See if you can spot the one that uses FSAA, and the one that doesn't.

Look in there: http://www.beyond3d.com/content/reviews/27/14


chwaga(Posted 2008) [#13]

what is the point of using antialias? for what purpose would someone want that effect?



Anti-aliasing removes "jaggies" aka artifacts from pixels. The hard edged pixels makes the pixels much more visible and can easily kill the mood of a game (especially on a low-resolution monitor). Also on thin geometry (line a car antenna), lack of anti-aliasing can leave very visible line artifacts (the line of the antenna would be broken into several lines with gaps in between). Play half life 2 without anti-aliasing and then with, and you'll see why the 'effect' is purposeful.


Jerome Squalor(Posted 2008) [#14]
that makes sense thnx