| spherical mapping |
zeefusion |
I may have asked this before but I cant find the thread nor remember the outcome.
So...I have a spherical map
I am interested in where those two dark chairs are positioned.
I apply it to a material slot on the material editor and as expected the chairs are in view on the material editor ball. The map is mapped to the outside of the material ball.
I create a sphere and apply the same map. And again the chairs are in view as it is mapped to the outside of the sphere. This is in the front viewport
Now here is where I get confused. If i apply the same map as a spherical environment. you are now inside the sphere. so everything is essentially flipped. If looking at the chairs inside the sphere they would be on the right hand side. So I create a camera from the front view still looking at the sphere. When I render the environment is not flipped, in fact it is not what I expected to see.
In order to get the two chairs in view I have to rotate the view 90 degrees to the left.
Why do I have to do this? I would have thought in order to get the same view I would have to just flip the map? I haven't flipped it at all, just rotated it 90 degrees. Here is the correct view from the left camera but as you can see you are looking at the wrong part of the sphere.
Its as if the spherical environment places the map randomly instead of aligning it to the front view. My suspicions tell me that if I tried it with a different map i may have to rotate it only 30 degrees to the left or something.
read 227 times 2/3/2012 3:05:02 PM (last edit: 2/3/2012 3:09:37 PM)
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herfst1 |
Can't answer your question but... where do you get those panoramic (?) photographs? Is there a site dedicated to them?
read 218 times 2/3/2012 3:18:23 PM (last edit: 2/3/2012 3:18:23 PM)
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zeefusion |
This is a jpeg I just pulled off Google images. It is not a HDR image or anything.
read 214 times 2/3/2012 3:28:10 PM (last edit: 2/3/2012 3:28:10 PM)
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Garp |
The way the map appears on the sphere is related to the sphere's mapping (depending on where the seam is) and the sphere's rotation. It is independent from the environment. Afaik, with the VRayHDRI map set to angular or spherical for the environment, the front view is facing the center of the image.
edit: I meant the left view. The positive X axis points to the center of the image.

read 207 times 2/3/2012 3:56:13 PM (last edit: 2/3/2012 4:08:10 PM)
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Dr. Jim |
You are inside sphere now. So chairs are behind you.
read 196 times 2/3/2012 4:11:42 PM (last edit: 2/3/2012 4:11:42 PM)
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BishBashRoss |
I am now thinking inside the sphere, pulling at the envelope. There are no chairs, just stumpy quadrupeds wrapped in there own skin.

Maxing and Relaxing
read 190 times 2/3/2012 4:22:56 PM (last edit: 2/3/2012 4:22:56 PM)
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Garp |
I just noticed something. Are you sure your environment map isn't tiled horizontally? The objects are very narrow and in the 3rd image from the bottom, it's mirrored: there are two identical computer screens in the render but just one in the image.

read 188 times 2/3/2012 4:26:58 PM (last edit: 2/3/2012 4:26:58 PM)
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zeefusion |
Oops I did it wrong... I had mirror ticked in the coordinates roll out. This caused the image to be on both sides. I thought it would flip it, not actually mirror it.
Anyway with mirror off I now see this
So if I then go to the camera at the back I see this:
Which is the correct view but it is flipped the wrong way. How do I flip it so that when I am inside the sphere I am looking at the two chairs on the left? I thought it was the mirror tick box.
read 178 times 2/3/2012 4:48:10 PM (last edit: 2/3/2012 4:48:10 PM)
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zeefusion |
Hmm if I use Vray HDRI the front view in the material editor it is different to the 3ds max environment front view.
The trolley to the left of the chairs is now in view. In order to get the chairs in view I need to rotate the map 90 degrees. and then flip it for the chairs to be on the correct side.
So I guess my question is why do i need to rotate it 90 degrees first? And is it always 90 degrees, or does it depend on where Vray decides to pout the seam? I get why you need to flip it because you are inside the sphere and not outside it. But I don't get why you need to rotate it as well.
read 173 times 2/3/2012 5:04:44 PM (last edit: 2/3/2012 5:08:04 PM)
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K-tonne |
try -1 in the tiling slot to revese the image
read 165 times 2/3/2012 5:10:40 PM (last edit: 2/3/2012 5:10:40 PM)
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Garp |
VRay and max do not set the environment in the same way. I believe VRay faces x positive while max face y positive. But they are both consistent, in the sense that whichever you use, if you set a camera to face, say, the left side of the image, it will still face the left side if you change the image (as long as you don't mess with the rotation or tiling, of course).
As for the inversion, the environment maps on the inside of an infinite sphere while the material applied to your sphere maps on the outside of it. Try with an image that has text in it, to see which one is the same way you see it in Bridge and which one is inverted. If I remember well, the vray environment mapping flips it (if a word goes from left to right in Bridge, it is flipped when the image is applied as an environment). Which makes sense, since when applying the image to an object's surface I'd want it oriented the same way I see it in Bridge or Photoshop.

read 156 times 2/3/2012 5:51:59 PM (last edit: 2/3/2012 5:53:16 PM)
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zeefusion |
Thanks Garp, That makes sense :)
read 151 times 2/3/2012 6:06:28 PM (last edit: 2/3/2012 6:06:28 PM)
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BishBashRoss |
Infinite sphere. *brain explodes*

Maxing and Relaxing
read 139 times 2/3/2012 8:41:48 PM (last edit: 2/3/2012 8:41:48 PM)
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