I encounter some difficulties in creating a spherical map for a skydome. (Probably something sillily simple)

-I painted a tga 500 x 500 pixel with some clouds in a circle on a blue ground.

-then I build a halfglobe from an 8-sphere.

-select from below new decal spherical then apply and stop positioning.

but dont get the desired result : a cloudy rounded sky. (see attatched picture)

it somehow repeat 3 times and doesn`t help when I alter this.

Can anybody please set me on the right track how to apply a spherical map correctly?

Try applying it to a whole sphere, not a half.


Edit... Actually I'd stamp that decal from the top as a regular flat decal.


Edit II... a spherical map needs to be laid out like a Mercator map, not a polar projection.

example. map applied to top, in pose that shifted middle ring to halfway between equator and pole, to eliminate stretching.

Click to view attachment

Click to view attachment

Click to view attachment

Trying further to understand that principle sperical decaling.

Made an mercator like map and applied it from the front.

Still not the ecpected result.

How the hell do you guys apply sperical maps and why is always this 3 X 3 tiling applied.

This principle still escapes me.

Any further help?

( I did apply the decal to a whole sphere as well but also no cloudy sky.)

I enclose the skymdl and the decal , maybe somebody could apply that spherically?

A:M really prefers mapping to 4-point patches. The 8 patch sphere you have is all 3-pointers.

For spherical or cylindrical mapping you really need to use a shape that has more splines and came from a lathing operation so that all the patches will be 4-pointers.

Oh, okay I see.
I will try

Thanks a lot.

So I tried with an 32 patch sphere now.

Result A is spericalmapped , but still not what I want.

I would like to achieve more a look more like B, C which are the planar-mapped versiona but therefor have a huge gap on the backside.

I am watching this with interest as I feel your frustration!

Steve

Do it this way

Click to view attachment

Correction:


Mercator isn't really the correct projection for use with Spherical Mapping. I believe the geometrically correct map would be "Equirectangular"


Mercator can never actually map the poles, while Equirectangular can, although it ain't pretty.

Thank you for that movie robcat.

Very good way to explain things.

I will continue my tests.
and thinking of having the skydome just have the color and putting the clouds on some cookie cut mapped clouds on one or more flat patch-planes.

I am looking for a way to create some backgound with clouds that is so light renderingwise, that it can be used for animation.