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Leonardo Vega
12-29-2007, 03:42 AM
Hi,

Let me say... Blender has improved vastly since I last saw it. It's incredible to see what open-source software can do. Great job to all who have contributed to it! :)

Just some questions...

1) Why is the "z" axis the height axis and "y" the depth axis? For example, in the top view, you see the "x" axis running horizontally and "y" axis going vertically, when it should be the "z" axis going in the vertical direction.

2) Do most of you use the built-in renderer or an external renderer? If external, which one?

3) Any world on when the next release is due up?

Thanks,
Leo

Leonardo Vega
12-29-2007, 04:57 AM
Also, any good resources for character animation / rigging?

I just saw a preview rig for the Rabbit (by Nathan) and it's awesome! Wonder how easily one could recreate that rig...

chewedon
12-29-2007, 07:12 AM
1) I don't know why the hell the person who did the axis don't follow mathematic convention, but I believe other software also don't follow this convention like 3ds max for example. Only Maya I saw so far uses the Y for the up axis.

When I asked the programmers that I often get retarded answers.

The most sane answer I got was "Blender uses the left hand system" or something.

2) I'm not sure about others but if I want GI, I use Yafray (external but integrated). Otherwise I'll just do my best with the internal render, hoping one day it'll be improved and have its own GI and other features (caustics etc).


3) Blender 2.50 is not going to be released until project Peach is finished. . and I'm not sure when that's going to happen. Maybe try next Christmas in 2008.

I don't even know what happen to Plumiferos, is it finish or what !?

For character animation and rigging, you can try:

http://wiki.blender.org/index.php/BSoD/Introduction_to_Character_Animation

fktt
12-29-2007, 09:43 AM
1) I don't know why the hell the person who did the axis don't follow mathematic convention, but I believe other software also don't follow this convention like 3ds max for example. Only Maya I saw so far uses the Y for the up axis.

no, actually Z's up in the Cartesian Coordinate system(or the modern rectangular coordinate system) and thats what blender follows i belive.
http://en.wikipedia.org/wiki/Cartesian_coordinate_system


The most sane answer I got was "Blender uses the left hand system" or something.


thats the right hand rule, see the wikipedia entry.
http://en.wikipedia.org/wiki/Right-hand_rule


and something else of interest:
http://homepage.ntlworld.com/r.burke2/tutorial.html#3dcoordinates

kattkieru
12-29-2007, 11:27 AM
1) No idea, but all of the export scripts compensate for this strangeness by rotating the model 90 degrees if you wish. (Check out the .obj exporter as an example.)

2) I've been doing quite a bit of testing with renderers lately. I second Yafray for GI. If you want good caustics Yafray's the way to go (although they're often faster to fake). The main difference between Yafray and Blender isn't terribly apparent, though, until you do a few test renders on the same scenes. Yafray is a bit "smoother." It doesn't do passes, though, at least, not with the current Blender SVN, so if you need to do any kind of multilayer compositing or post-pro you should stick to the internal renderer (which is quite capable imo).

Sunflow's also nice. It produces beautiful renders if you have the patience to play with it. Personally I don't use it because Yafray's easier.

Lastly there's LuxRender (http://luxrender2.org/), which shows promise but is still in its early stages. Once it gets MLT built in I'm going to give it a serious look.

3) 2.5 will be a little later than most people expect, now that Ton's rewritten the event model. The bonus is that, when finished, Blender'll be on par with some high-end apps in terms of configurability. In the post they mentioned possibly doing an unsupported tech preview before the real 2.5 is out, one that has all the Peach bonuses in it. Personally I build from SVN every week or two, and the current SVN build is both stable and full of new goodness.

But it won't be next Christmas, I don't think.

chewedon
12-29-2007, 01:01 PM
no, actually Z's up in the Cartesian Coordinate system(or the modern rectangular coordinate system) and thats what blender follows i belive.
http://en.wikipedia.org/wiki/Cartesian_coordinate_system



thats the right hand rule, see the wikipedia entry.
http://en.wikipedia.org/wiki/Right-hand_rule


and something else of interest:
http://homepage.ntlworld.com/r.burke2/tutorial.html#3dcoordinates

The cartesian coordinate I learn in Calculus when I was in high school year 11 and 12, Y was the vertical, X was the horizontal and Z being the far/near.

The same thing also when I learned OpenGL from the red book:

http://glprogramming.com/red/chapter03.html

(scroll down to "Thinking about Transformations" or hit Ctrl + F to do a search for that phrase)


Here's a screen shot of the coordinate system in Maya:

http://img.photobucket.com/albums/v639/Ryu_Kaiser/cartesian_coordinates.jpg

:)

chewedon
12-29-2007, 02:17 PM
1) No idea, but all of the export scripts compensate for this strangeness by rotating the model 90 degrees if you wish. (Check out the .obj exporter as an example.)

2) I've been doing quite a bit of testing with renderers lately. I second Yafray for GI. If you want good caustics Yafray's the way to go (although they're often faster to fake). The main difference between Yafray and Blender isn't terribly apparent, though, until you do a few test renders on the same scenes. Yafray is a bit "smoother." It doesn't do passes, though, at least, not with the current Blender SVN, so if you need to do any kind of multilayer compositing or post-pro you should stick to the internal renderer (which is quite capable imo).

Sunflow's also nice. It produces beautiful renders if you have the patience to play with it. Personally I don't use it because Yafray's easier.

Lastly there's LuxRender (http://luxrender2.org/), which shows promise but is still in its early stages. Once it gets MLT built in I'm going to give it a serious look.

3) 2.5 will be a little later than most people expect, now that Ton's rewritten the event model. The bonus is that, when finished, Blender'll be on par with some high-end apps in terms of configurability. In the post they mentioned possibly doing an unsupported tech preview before the real 2.5 is out, one that has all the Peach bonuses in it. Personally I build from SVN every week or two, and the current SVN build is both stable and full of new goodness.

But it won't be next Christmas, I don't think.

Wow ! the Lux Renderer looks so good and it's open source too.

The cool thing most of all is its name :)

Leonardo Vega
12-29-2007, 08:03 PM
I have never used an app personally where "Z" was the height axis. I mean, is it so hard to just change "z" to "y" and vice-versa? Do the majority of ppl actually prefer the current system?

Anyone give the Indigo renderer a try?

When I render in Yafray, I don't see any kind of progressive rendering, the screen is just black for like 10min, then bang, the image appears. Is this normal?

What is project Peach anyways? A game or movie? I saw these furry rabbits/squirrel renders, but can't understand what it's all about.

pnoland
12-29-2007, 08:19 PM
As far as I know that is normal for Yafray. It would be nice if it would be progressive or bucket to preview bits as you go but alas it is not a perfect world. :)

Peach is the next movie to follow Elephants Dream. I can't wait to get the updated version with the new things they're working on like the fur renderer and tools...

fulg0re
12-29-2007, 08:52 PM
Yafray does have progressive rendering, just turn of the xml button in the yafray panel before rendering. There is also a another great renderer kerkythea http://www.kerkythea.net/

toontje
12-29-2007, 09:37 PM
@Chewdon:
Peach is scheduled to be finished by the end of March 2008 (and they seem to be right on track).

Internal renderer: None of the software packages has a button that says: Render realistically. Uhm.... well ... unbiased renderers has.....but they converge after hoooouuuuuurrrrssssss.

I can easily render a realistic scene with Blender with little effort.... in fact just check my thread for an example:
http://blenderartists.org/forum/showthread.php?t=111769

And what about that fast SSS huh?
With the next release Blender Internal will be better than ever. Not the best renderer, no way, but it is a decent renderer.

Z-axis as the up axis is the best and mathematicaly sound solution. Z-axis as being ' the depth into the monitor' was just a marketing gimmick way back in the old days. Maybe it was the easiest way to explain/ introduce the ol' 2D public to the third dimension. ANd early software stuck with this paradigm.

pnoland
12-29-2007, 11:01 PM
Ahh, thanks for that tip! Kerkythea is a nice engine, does it support subdivision surfaces yet? I recall it not having that features when I first heard of it (long while back...)

Yafray does have progressive rendering, just turn of the xml button in the yafray panel before rendering. There is also a another great renderer kerkythea http://www.kerkythea.net/

Leonardo Vega
12-30-2007, 03:27 AM
I'm not mathematical, but I don't see how "z" or "y" is a smarter choice for the height axis... it's just a letter. I just prefer "y" because I was raised on "y" being vertical (over 10 years of using 3D apps)... so mentally it throws me off.

But that aside, I'm not complaining... this app deserves praise for what it has done and continues to do.

"Peach is the next movie to follow Elephants Dream. I can't wait to get the updated version with the new things they're working on like the fur renderer and tools..."

So I take it the developers are working on the Peach movie and as they go they add features to aid their work, and this in turn gets added to the public release?

I hope they release training videos on how they created those awesome rigs! Man, super nice... I'll pay those DVDs!!!

BTW, anyone check this DVD out? Click Here (http://www.blender3d.org/e-shop/product_info.php?products_id=99&currency=USD)

- Leo

Michael-Williamson
12-30-2007, 12:14 PM
I'm not mathematical, but I don't see how "z" or "y" is a smarter choice for the height axis... it's just a letter. I just prefer "y" because I was raised on "y" being vertical (over 10 years of using 3D apps)... so mentally it throws me off.
- Leo

I started out in architecture way back (1989) and because you mostly draw plans to start out, a 2d building plan defined the xy plane, you then added height to the buildings giving you z axis for height...

a lot of cad follows that convention...

In computer graphics, the screen is normaly defining the xy plane (most people have the screen vertical!) with z being depth.

as 3d authoring packages grew, cad vs maths basis led to a split, seemingly at random
about which axis should be up... as you say, that which you "grew up with" seems most comfortable. It is strange in blender that we still have the "z buffer" which is screen depth but then again, the camera local z is depth into the screen... that's why the cameras get added facing the floor!

none of it matters once you get used to it, but I'll shut up now!

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