Sphere texture from a not square image

Hi to all!

I've read about ways to make a good texture for a sphere.

Well, I've a similar need. I've two images represented by two discs (each is half of the sphere). How I can transform in one squared image to apply to a sphere?

Sorry for my english

TY

Hi Imajica! (Your English is fine, by the way!)

The only real way I know to do this involves a third party plug-in; but it's not expensive, and runs in both PS and PSP. Let me show you how it works. I'm using this test image.



1. Download the Flexify 2 plug-in from Flaming Pear here and install it in your graphics program. (I'm using Photoshop.)

2. Separate your two half spheres into two different images, if they aren't already like that.

3. Select each one, and run Flexify with these settings.



(I'm only showing part of the interface, with the Preview out of place, so you can see it all, but it's not even bigger than it is now.)

4. Take the two resulting images, and combine them into a single image, so they look like this. To do this, you need to rotate one of them 180°, and offset them, of course. (If you get them the other way, it's not a huge deal. You'll just have to offset them in SL.)



5. Run Flaming Pear Solidify, (available at the same page, in the Free Plugins pack), to take care of the semi-transparent edges in the middle of the picture. (It's possible that there's a way to run the filter that doesn't leave them, but I only downloaded it to answer this question, and if there is, I don't know it. Yet.)

6. Size as a Power of Two, Save as .tga, and upload to SL.

7. In SL, apply the texture to your sphere. Here's an example of the finished result, using the same test image.



As you can see, it's not perfect; but it's pretty close. (Far, far closer than is possible to get using any other method I'm aware of.) This is actually two shots, so you can see the result head-on for each half of the sphere, as well as what it looks like from the side. The distortions are a result of using this particular image as a test, and wouldn't exist if this was, for instance, a photograph of a ball from the top and the bottom.

By the way, the poles (where the image pinches) are smack dab in the middle of the test area, facing right into the camera. So you can see how well the filter compensates for them.

I think I'm going to go pay the $35 shareware fee for it now.

I've not enough words to say "thanks"...

but... Thank you Robin!

So, I need to build a rotating earth. I've not right textures, but waiting to find, I will try with some bad pictures I've found (bad because I've shadows areas). Well, to do that, I need to use your tutorial (very well written).

Thank you more!!!

These folks might be able to help you with a texture: http://earthobservatory.nasa.gov/Newsroom/BlueMarble/BlueMarble_monthlies.html

And Robin is teh r0xx0rz with textures! *bows*

I think I will pray all day for you and Robin... You've helped me a lot... Thanks Thanks Thanks Thanks Thanks!

I didn't know you wanted the Earth, Imajica!

That's much simpler!

There are tons of places that you can get a good Earth texture, and you don't need to do anything special to use it in SL.

Just get one that says that it's an Equirectangular Projection, and you can just slap it on the sphere in SL without any more work.

I'd recommend Björn Jónsson's page if you want realistic maps of earth, or any of the other planets. (He allows this use, and just asks that you let him know where you've used them.)

There are various sites run by governments that have images you can use, too. Just Google the terms "earth" and "equirectangular" and you'll get tons of stuff. Then all you have to do is check to see what kind of use they allow, and go from there!

Hope this helps!

I'm sorry for less informations, but I dont know they exists equirecatngular maps... lol

So, your tutorial is very useful, generally, to build a texture from circular image.

But now I expose all my needs. I've tried with these maps
and I've build a very nice earth in SL.

But I've realized I need to build an huge earth. So, I cant use a sphere, because is not enough bigger (i need about 3-4 time muche bigger).

So, I've think to use some of free tools to build a sphere using planes.

Well, is good, but is not so good as I want. But I cant have alternatives and I must use that. Also, I can use too much planes and too much sizes, because I need to link all (too far objects or too much objects).

At last, I must use different textures for each plane, or same texture with differents offstets.


Finally... I cant do what I want

But thank you anyway, because I've learned a new things and I've found a lot of maps interesting!

Is weird... today only I've realized I've lost my previous reply.

So, I would like to say what I want really.

I would like to build a sphere, using earth texture: that is done, now.

But I can build a sphere of 10meters maximum.

I need to build a very bigger rotating sphere (about 30meters).

I know I can using some free tools what build a sphere using a lot of panels, but that means I cant link all panels (too far and too much panels).

finally, I've realized I cant do what I want!

But, thank you. I've learned a lot of new useful things!

Bye