Dominance War V - 2D - The Immortal - washka

[wil_himura]

I made a drawing... I'm not sure it's working. Maybe because all my 3 points are too close to each other, don't know....



If distance between points 1 and 2 was bigger, The bissectrice wouldn't be that / and more like | hehehe

Aproximations... bah :P

As I told you, since you put points 1 and 2 where it suits your idea, the same applies for point 3. I'd say as far of the other points as you can

[hulahuga]

Well if you want the focal thingy, either do it the free style way or apply your perspective lines and from that curve them off when they grow closer to the edge...

[DeadlyFreeze]

You want curvilinear perspective the "fish eye" distortion type effect? It's not that hard to setup its a 5 point system.

[mix_mash]

The alternative is to create what you want in 3d with the perspective you want then paint over it as reference. I know it may be considered 'cheating' but it is just an option.

Paul
(mix_mash)

[washka]

Thanks wil_himura, I better understand your bissetrice rule now, nicez!

or apply your perspective lines and from that curve them off when they grow closer to the edge...

Yeah, it's something like that I'm looking for Hula.
On the big central perpendicular cross section, this kind of conical distort is low but it grows when you're approaching corners.

But there should be some geometric rules there, I think the bissectrice rule will_himura pointed to me will help.

DeadlyFreeze:

You want curvilinear perspective the "fish eye" distortion type effect? It's not that hard to setup its a 5 point system.

5 points: So => Center-Far Left-Far Right- Far Down - Far Up ?

Can you also go 8+1 or 16+1 ? Circular patterns?
What happen with diagonal vector fields (The 2 points rules in local mode)? Rules there?

Imo I think it's hard, not the setup you're pointing, but the way all this perspective thingie works.
If you've got some good reference I'm really interested.
I'll go google/search my database a bit more, because trying to understand that on my own is a kinda stupid and loss of time.
Thanks for your comments!

[washka]

The alternative is to create what you want in 3d with the perspective you want then paint over it as reference. I know it may be considered 'cheating' but it is just an option.

Paul
(mix_mash)

Did some 3D test for that => #179 (color one, volumes are still quite abstract, and lightning s*cks)
You can always cheat, sometimes I do, but I prefer to understand, it's way more rewarding.
Sometimes you can even combine both. xD

This vanishing lines concept is quite impressive (points perspective), because those just represent directions, the =same= direction, (colinear vector field), it's radiant and those are geometrically parallel. Wohohooo!!!
That's really disturbing, because depending of your volume's direction in space, you could choose any far away points.
Beside that your horizon "line" is a plane, so everything overlaps, even foreground elements, horizon line is not just "far away", it's also "right in front of you", that's also disturbing, and I'm not even talking about the bending of the space...

[Edit]
Started right dragon "general please", still messy, need to clean and refine, anat, tweaking, torso+front legs part should be more to the right.

[DeadlyFreeze]

A "true" 180° grid is laid out as such, with the horizon as the circle if one was looking down or the intersecting blue line if looking from a normal perspective.



Of course you can use curvilinear with a much smaller FOV, which seems to be what your trying to get at.

I've never heard anything in perspective called a 'vector field', so I'm not really sure what your referring too in your notes?

[Puckducker]

Geez Washka, those are some pretty solid notes/investigations on perspective....maybe you should be putting together a book after the competition.

[washka]

DeadlyFreeze: Wow that's really interesting for me!
How does this grid work, for the cicular horizon??? (already ~ understood how the mid line one works)
Depending of the object's postion, angle/ orientation?
But the "curving"also change with depth no?
Do you use the green lines too?

you can use curvilinear with a much smaller FOV,

I've been using curvilinear coordinates a long time ago (basics), those still a bit numb in my memory, differential calculus/curved surface/vector functions, but I'm not sure I should use something so complicated here? Are we talking about the same thing?
http://en.wikipedia.org/wiki/Curvilinear_coordinates

Also found this:
http://www.termespheres.com/perspective.html

"vector field": That's not in perspective courses, just geometry concept, I'm switching from the direction concept (that I related here to a line that pass by a determinated point) to the vector field one because it's easier for me, fields apply to all points of the space, in this case I was just thinking about the simplest one: parallel normalized vectors, all pointing in the same direction. (Unrelated to any point) => vanishing lines (those are colinear/parallel in real world/out of a perspective representation)
But this concept is quite messy with the perspective one, because the colinear/parallel concepts change (or disapear, I don't know).
If you've got more infos about how this 180° grid work, I'm interested

Geez Washka, those are some pretty solid notes/investigations on perspective....maybe you should be putting together a book after the competition.

Puckducker: There is already people doing that faaar better than me, and there is already tons of books about perspective(s) far better than anything I could even write xD. But thanks for the encouraging comment, I just want to understand how this stuff works.
(But maybe in a few decades, if I've learn enough and that I think it could be usefull for anybody in 2D painting, we'll see then.)
What I've learn today is: About depth, I think our brain is a funny one.

[Warlock 279]

Ya'll are gettin' heavy up in here! Make mah head hurt! I used to understand all that stuff [most of it anyway], then I got into 3D, quit using it, and have since forgotten most of it. Your studies look pretty good. I'm with Puck, when's the book coming out? Might have to pick myself up a copy. :P

The only thing I don't agree with is the bottom left corner, the building. I believe you actually see the second example all the time, whether your horizon line is parallel to the ground or not. Its just a lot more pronounced when you're looking up at an angle because you're closer to the building, vs when you're far enough away that you can see the whole building straight on.

DeadlyFreeze's image is what we see all the time, with 5 vp's, regardless of where or how we look at something. Translating that into art [or even really taking note of it in the real world] is extremely difficult as its a very subtle thing. We're really typically only "aware" of the one or two point perspective depending on what we're looking at. If we're looking down a hallway, we're gonna be made keenly aware of what seems like single point perspective. Generally we're aware of two point perspective because we have a much wider field view than we do vertical field of view. We become "aware" of the 3 point perspective [or in extreme cases it appears to become an altered one point] if we're standing close to and looking up at a building, or conversely if we're looking down into a hole/shaft/deep pit/etc. Regardless tho, all five vp's are present, we're just not "aware" of them because our focus is fixed on only one.

As an artist drawing with perspective, we can pick and choose which want to emphasize a look or feel, and control how the viewer sees the image. You've done a lot of nice studies, and it looks like you're really getting a solid handle on how to translate the 5 vp's, into a working 2d image.

Dragon is coming along nicely.

Seems I crossposted with you. Just want to add...yes...the brain is a very very funny thing, and very easily manipulated or tricked, especially visually.

[hulahuga]

DeadlyFreeze's image is what we see all the time, with 5 vp's, regardless of where or how we look at something. Translating that into art [or even really taking note of it in the real world] is extremely difficult as its a very subtle thing. We're really typically only "aware" of the one or two point perspective depending on what we're looking at. If we're looking down a hallway, we're gonna be made keenly aware of what seems like single point perspective. Generally we're aware of two point perspective because we have a much wider field view than we do vertical field of view. We become "aware" of the 3 point perspective [or in extreme cases it appears to become an altered one point] if we're standing close to and looking up at a building, or conversely if we're looking down into a hole/shaft/deep pit/etc. Regardless tho, all five vp's are present, we're just not "aware" of them because our focus is fixed on only one.

+1

What we actually regard as our peripherals are when we grow closer to this rim, and it is only there that the perspective grows distorted... So a five point is not really necessary unless you want to draw an artificial "fish-eye" perspective .

All in all this can be used to play a lot with the image to create some very interesting effects. And it is also one that artists actually should try to play with more in their compositions

[mix_mash]

You know, what you REALLY need to help you with perspective is this: Pay a beautiful female model to pose nude for you and....

...I forget the rest....




Paul
(mix_mash)

[DeadlyFreeze]

Originally Posted by washka

How does this grid work, for the cicular horizon??? (already ~ understood how the mid line one works)

The circular horizon comes in to play if you are actually top down on something. Since the lens is at a fixed distortion all lines converge back to the horizon, top down at 180 degrees it becomes the outer circle. In the link you posted see the 5 point and imagine those are buildings your looking down on.

It's not really the true horizon per say, but rather extreme distortion cause by the lens.

Originally Posted by washka

But the "curving" also change with depth no?

Depends what you mean by "depth". You have to remember depending on what your looking through is the key to all of this.

The FOV for human eyes is 60 degrees, but looking through a fish eye lens it's 180 degrees. Assume our curvilinear grid is infinite, the more you zoom in the less curved it becomes, but your really just changing the FOV.


As to how much curvilinear coordinate system relates to curvilinear perspective, I honestly have no idea.

[washka]

Warlock 279: If your head hurt, rather it is a good sign than a bad one.
I'm sure those notes are full of mistakes, I agree with you about the thing you say about the building, another exemple about that: a corridor can be seen as a small building build horizontally instead of vertically, you just don't move your head up.
And when it's far (far) away, as DeadlyFreeze explained, you're changing zoom/FOV, the vanishing are kinda closing as an umbrella (I should said umbrellas => lens), the "bursting" seems to decreases with distance.
But I think there is a trick there too, if there was some =enormous= building far far far away, those distorting rules would apply (I think), big scale would open da umbrella, so distance and scale. No?

much wider field view than we do vertical field of view

This awareness for horizontal things you're talking about is so true, and it's an important data imo, I won't forget that.
Thanks a lot for your whole comments, comments I always appreciate a lot, even on others threads.

Hula:

unless you want to draw an artificial "fish-eye" perspective

Not completly "fish eye", just a bit, especially for down/top/sides parts/ and corners, ok a bit more than just a bit, but not some exagerated distorsion. Fish eye scale up a =lot= center part, I don't want that.
I just want people feel this depth on the image, and get some size/proportion/geometry coherence.
I had Lens 24,0 mm FOV 73,74 deg, on my 3dsmax test, it's quite open, I'll close it a bit to ~70-72 deg.
Hope I'll get some interesting result for this Hula, and that you'll gimme a feedback after the comp'? (if it was worth it or not)

You know, what you REALLY need to help you with perspective is this: Pay a beautiful female model to pose nude for you and....

mix_mash: I think I'll start with basics drawing with landscape outdoor, there is some nice hight places where I live that can help, and summer is starting.
The day I'll get some money from what I do, some day I'll ask the model to pay me instead (revenge ).

...I forget the rest....

That always happen when you're starting nude study, that's a real problem, but it ends up spending.

DeadlyFreeze:

In the link you posted see the 5 point and imagine those are buildings your looking down on.

From a balloon, if I completly look down exactly above a city, that's what I should see. Ok.
Now if I rotate all the space 90° and I imagine an opaque plane cutting it horizontally a bit under the mid => I'm back onto some kind of 2 points persp (2PP). What difers the most, corners/ far top/down, that's caused by the fact in 2PP vertical lines are not "blend" by top/down points in 5PP. But here "horizontal awareness" warlock pointed is a good argument for the 2PP model.

Depends what you mean by "depth". You have to remember depending on what your looking through is the key to all of this.

Oh man, I'm starting to understand why this "depth" concept doesn't quite fit, side data compared to pointing, objects there: we see those a little bit further than they are irl (lens effect), am I wrong?

Assume our curvilinear grid is infinite, the more you zoom in the less curved it becomes, but your really just changing the FOV.

When I zoom in into fish eye-model, blending drop with FOV, umbrella is closing.

Starting to get a bit more clear in my head, thanks a lot. I'll see how I can use all this stuff now. In fact this kind of perspective approach will be interesting for this and somes other parts:

-Just a fast messy photomontage using some Kylie Minogue:"All the lovers" refs, still some repetition/mirror to kill, lot of details to erase and rebuild, I'll paintover as much as I can.

[hulahuga]

Hope I'll get some interesting result for this Hula, and that you'll gimme a feedback after the comp'?

Of course