panorama sphere preset

[Flexi]

so, this one tortured my mind for so long and now i did it - a panorama viewer for my spherical photos!
Due to the big textures i uploaded on the stashbox:

http://stashbox.org/v/358535/panorama%20sphere.zip

hope you like it.

[Flexi]

[Flexi]

[Flexi]

[Flexi]

damn, i didn't listen to our local radio for 2 or 3 weeks. i switch on and they play the Electronic Panorama Orchestra. and i like it.
(edit: found some tracks on the web and changed link above)

I'm going insane. i do. really. listen to Lohro ↓

[Cope]

that's a nice hack

I was going to play around with it, but then I got caught up in tinkering with those domain coloring presets for some hours

I wonder how it looks with a one of the Hubble's high resolution images...

[Flexi]

if you, like me, once were interested in POV-Ray try these camera settings with a scene:

code:


// spherical lens for sphere field of view (mappable to a sphere)

camera {

  spherical

  location <0,0,0>      // position

  look_at  <-1,0,0>     // view

  angle 360             // horizontal degrees

        180             // vertical degrees

}

so you can easily create panorama textures yourself. (you can also use my panorama photos as sky sphere in POV-Ray and simply extend them)
Don't know if you can set up a spherical camera with Terragen, but that would be even cooler.

what is our milky way then against some human artistic brainpower?
creationism

I will try to clean up the code by this evening. now it's about 140 ops, but i think i can reduce this and then i will also write a short text on the techniques used

[Cope]

try it with earth textures from here

http://oera.net/How2/TextureMaps2.htm

combining the cloud and land maps into one image in photoshop gives a really nice look, and you could even go further and use the bump map to give it a 3D look.

this all leaves me with one question though... is it possible to render a sphere seen from the outside with a method like this? could we have a planet earth floating through our scene?

[Flexi]

yes, i'm sure that's doable. spheres are the most easy to ray-trace and it can be done in far less than 512 operations.
Thanks a lot for the textures - the Lorenz Attractor makes a great impression with the stars map!

Anthony Rother - Hacker

i will go for the spheres. here's a raw plan:
- every pixel on the screen constitutes a light ray from the cameras point of view (assuming the cameras position at the point of origin)
- check if sphere is hit (parameterization here, defining the distance, the sphere's radius is set to 1)
- if so, calculate 3D coordinate on the spheres surface (attention: it's two possible solutions now - select the point nearer to the camera)
- rotate the 3D point to make the sphere able to spin in 3D space
- calculating polar coordinates from the 3D (unit) vectors
- in case sphere was hit, texture the pixel

note that all the silver bulletins are already implemented in the sky sphere code

edit: *lol* i just switched on the IndiePopRocks stream and they play Spinning Lucy - Starsign it's weird, I'm haunted and it makes no sense... (besides i'm a capricorn with ascendent capricorn - one of the mountain goats type, you know?)

[Flexi]

are you ready?

it uses the natural texture and the clouds texture from cope's link (http://oera.net/How2/TextureMaps2.htm)
and i named them pano_earth.jpg and pano_earth_clouds.jpg

now working on the re-integration of the milky way sky sphere.

please be so kind and leave me a note what's your frame-rates.

(hint for ATI users: MD2.1beta is needed)

this is so far out

[Stahlregen]

Awesome!

49 fps @ Intel Core Duo 1.73 Ghz, 1 GB Ram, Ati Mobility Radeon X1700

[Cope]

WOW! that's exactly what I had in mind!!

full 60 fps @ 1680x1050 with my HD 4870, still lots of room to crank that puppy up

[Flexi]

this one also needs the stars map texture as pano_starsmap.jpg and the mars texture map as pano_mars.jpg

[gaekwad2]

Originally posted by Flexi
please be so kind and leave me a note what's your frame-rates.

56.88

Core 2 Duo E8400
GeForce 8500GT (not exactly a fast card)
fullscreen 1280x1024
milkdrop at default settings, max fps = 60

[Flexi]

good to know. thanks - but i think i will stop growing it more complex for now.

lean-back-and-watch-time now

here's one more simple precursor version

[ShadowHarlequin]

looking forward to checking these out in the morning *bed time atm*

is it just me that gets an error when tex2d is used instead of tex2D?

[Flexi]

i thought this issue was cleared with the MD2.0c or d version - you don't use the current 2.1beta?

Tagtraum - Ich will die Welt

[ShadowHarlequin]

yeah i have the beta an everything :S

[Cope]

If you add change the ret lines to this:

ret = p;
ret += mask*tex2d(sampler_pano_earth,polar);
//ret = lerp(ret,1,mask*tex2d(sampler_pano_earth_clouds,polar)*mid_att*0.5);

you can see the different domains overlayed onto the earth, cool

[Flexi]

heh i tried that too when i was working on the 3D rotation.

say, do you think the 'alienation' preset is too wild? I'm not sure, but i think i have to reduce the tempo a little bit.

anyway i will work over the 3D rotation stuff: when watching a planet there's no need for a roll, and yaw can be done by a simple shift in the texture look-up. so only for the pitch a multiplication/rotation is needed. It's fair to say this won't reduce many operations but at least the code will become a little shorter.

[Nitorami]

Originally posted by Flexi
heh i tried that too when i was working on the 3D rotation.

say, do you think the 'alienation' preset is too wild? I'm not sure, but i think i have to reduce the tempo a little bit.

anyway i will work over the 3D rotation stuff: when watching a planet there's no need for a roll, and yaw can be done by a simple shift in the texture look-up. so only for the pitch a multiplication/rotation is needed. It's fair to say this won't reduce many operations but at least the code will become a little shorter.

Ah, a proper spherical projection at last. Has something similar in mind but never really took the effort to think it through. I must say the correct formulae look much better than the simplistic tangens approach I used.

On the speed issue: I don't like the jump movement of the earth in the original "blue marble" and think it just does not suit the topic. If the planet wasn't so realistic I would not care, but since it is, it annoys me to see it jump around. The true earth wouldn't do this... I'd rather fly around it slowly, maybe dive down close to the surface, then lift off again, possibly with the rising mars visible over the horizon ?

On the alienation preset I'm not sure whether I see what was meant to see ...? The realism is gone, instead I see mars and earth texture overlayed, a distorted sky passing by in the background and a white spring which seems to act as a separator. In this case I feel that speed and erratic movement don't matter because the scene looks artificial and only vaguely resembles true planets anyway, so why bother ? It is very GPU demanding, runs at 20fps only even in windowed mode on my GeForce7600 GT, and takes its time to load. With all the movement and distortion, I think the high resolution jpgs are wasted, and could be replaced by smaller resolution files, for the benefit of faster loading ??

[Flexi]

i will give it a try with lower resolution textures. but you will have to tell if it affects loading times since it's almost immediately on my machine.
on the "distorted sky" - is it too distorted? - then i could lower the cameras apex angle.
the blue marble preset is just the very first of its kind and after all i don't like the direct input of the bass value myself. at least i think it's an impressive tech demo with a lot of potential for further development. same on the alienation preset. i must admit i was pretty overwhelmed of the outcome and i couldn't resist trying a quick remix (ehm, do 2 hours count as quick?)

[Stahlregen]

So flexi, when can we expect you to have finished a beat-driven virtual orrery?

I accidentally found some delicious Planet textures, too:
http://planetpixelemporium.com/planets.html

Also, I thought this would go well with your terraforming remixes of fishbrain's witchcraft (needs the star map as pano_starsmap from here, too - but maybe someone wants to try and render pure shader stars? *glances at nitorami*):

[Nitorami]

Originally posted by Flexi
i will give it a try with lower resolution textures. but you will have to tell if it affects loading times since it's almost immediately on my machine.
on the "distorted sky" - is it too distorted? - then i could lower the cameras apex angle.
the blue marble preset is just the very first of its kind and after all i don't like the direct input of the bass value myself. at least i think it's an impressive tech demo with a lot of potential for further development. same on the alienation preset. i must admit i was pretty overwhelmed of the outcome and i couldn't resist trying a quick remix (ehm, do 2 hours count as quick?)

To be precise, texture loading for alienation takes 23 seconds on my AMD Athlon 3200+ with a 250G SATA disk. It is faster of course when the files have been cached already, approximately 1.5 seconds. Here is a sample of how it looks:

[Cope]

I like alienation, the planet jitters a bit too much though.

next thing is to add a sun and a night/day side for the planet

[Flexi]

@martin: the screen-shot looks pretty different to the results on my screen - there's no rectangular distortions to see on the star map in the background. it should be a fine sky sphere projection.

23 seconds you say? as i said, no noticeable loading issues here neither.
i would love to find out this bugs roots - does the sky sphere look the same in the milkdrop 3d hack preset?

[Nitorami]

No, the 3D hack works very smooth and nicely; just the alienation appears to be chopped

[Nitorami]

Here's another screenshot: appears somehow broken.

On the loading time: Have you rebooted to force the textures being loaded from disk ?

[Flexi]

the displacement mapping is totally overloaded on that image.

if you bypass the comp shader you see the green color patches. normally the green part itself should be transparent to the sky sphere too, and distortions are only to be expected at the borders

http://www.youtube.com/watch?v=PGB-Uubr0Wc&fmt=18

[Stahlregen]

Originally posted by Stahlregen
but maybe someone wants to try and render pure shader stars? *glances at nitorami*):

Silly me, I knew I had seen martin do this before. Found the star code in skywards...

So, texture-free version:

[Flexi]

that's magic!

http://www.youtube.com/watch?v=zva2pR39NJg
http://www.youtube.com/watch?v=4NzUuPt0NFQ

[Flexi]

only found a very little time today.
here's another quick idea:
i left out the polar coordinate recalculation in the final step, but projected from the 3D values directly in the hq volume noise texture - so there are no more annoying distortions on the poles.
i also normalized the rgb value to gain maximum dynamics for future remix fun

[Cope]

I think you'll like this flexi

this one really needs to be fullscreened

[Nitorami]

Originally posted by Flexi
only found a very little time today.
here's another quick idea:
i left out the polar coordinate recalculation in the final step, but projected from the 3D values directly in the hq volume noise texture - so there are no more annoying distortions on the poles.
i also normalized the rgb value to gain maximum dynamics for future remix fun

Hmmm ... ? Either you uploaded only a fragment or my download does not work, in any case I get only a milk file of 30 bytes length. I deleted the cache already and restarted the browser, but that did not solve the problem

[Flexi]

sorry, my fault.
i renamed the file just before uploading

edit: http://www.youtube.com/watch?v=fjUMZvLvzLQ

[Nitorami]

Ah ! Now I think it would be most interesting to project the warp shader output, rather than a noise map, onto the planet.

I tried it, but this seems to demand for yet another transformation to avoid distortions. The warp shader output cannot be correctly mapped on a spheroid but needs to be transformed similar to the earth map images. That sound tricky and like double work... maybe my mind is just stuck. Do you think there is a way around that ?

[Flexi]

stahlregen already did a mapping from the warp shader - and that's already the best result you can expect because a sphere and a torus are not topologically equivalent. that's why i think there's more fun on reworking the noise map. maybe fractal equations?

offtopic: last saturday evening, a meteorite flew over my hometown. It was to see in north germany, denmark and finally in sweden a webcam got it on tape. fascinating spectacle, i only saw a flash of it.


oh, and how do you like this canvas?

[Nitorami]

Now that's one comet, never seen such a bright one. Need to built one into the preset I'm currently working on.
Btw, swedish sounds funny to me.... "Visa inslaget igen" means probably "view impact again"

I remember yin's preset. Looks a bit scanty these days. It inspired me to a similar work using shader support, but I haven't got far yet. Started off months ago, using a simplified projection, which is rather a swelling than a proper spheroid, but comes reasonably close provided the masking is a bit over-restrictive to hide the artefacts. The advantage of this projection is that it does map the warp shader output despite the different topology. Never considered why really... it just came out like this.
In the study attached I overlayed 3 "spheroids" of different radius. To my eyes, the projection error is not immediately evident, but it does stick out at higher rotation speeds.

[Stahlregen]

Originally posted by Nitorami
I remember yin's preset. Looks a bit scanty these days.

The blessings and curses of shader support - there's so many presets I remember as totally awesome when I first saw them six or so years ago, but nowadays with all the shader bling they have somehow lost their shinyness...

Anyway, I went back to the terraforming preset and made some tweaks: more repeats of thetexture, desaturated the colors, buffered/slowed the reactiveness, added layered stars to give more depth and added some clouds shadows stolen from cope's blue marble (which is totally awesome, too - although the static night half cvould use a bit of improvement).

[Cope]

Time is short these days with exams coming up, but I've a few questions flexi.

I want to play around with simple ray tracing so I'm looking at the shader code in the blue marble preset to see what everything does, and a few things are confusing me.

code:


float camera_apex = atan2( length(c),z);

bool mask = mask_apex >= camera_apex;

float longitude = atan2(c.x,c.y);

float latitude = (pi - camera_apex + asin(d*sin(camera_apex)));

Something about this is throwing me off. Here's an algorithm I found for finding an intersection between a ray and a sphere, does the code above fit into this somehow? Or did you use a different method?

code:


E: ray origin

O: center of the sphere

V: ray direction



v = dot_product( EO, V )

disc = r2 - ((dot_product( EO, EO ) - v2 )

if ( disc < 0 )

      no intersection

else

      d = sqrt( disc )

      P = E + (v - d) * V