I need to to create a twisted tunnel. Example:
Though the stripes should have volume since the tunnel is the inner side of spiraled marshmallow tubes. Example:
I started adding a screw modifier to a plane which looked promising from from the tutorial, though not on the inside:
Any ideas or should I try to start with a bended cone, add a twisted color ramp & bump?
The hard way
But the way you can use to pour sugarlicious material on.
As usual we'll begin with a simple vertex. Easiest way is to add a cube, or plane, and go into edit mode, vertex select mode, select all with A then Right Click > Merge > At Center.
Add a Displace modifier set to X, lower the midlevel and increase the strength. Don't mind the vertex group, you don't need it.
Add a Screw modifier, increase the screw, iterations and steps (viewport and render)
Let's give it some thickness ! First add another screw, but set the steps to 1.
How to create a noodle. Don't worry about the wonky shading just yet.
Add a Bevel modifier set to angle and crank up the width. Add a Weld to remove the seam in the middle.
The tricky part. Add an empty, set it as the object offset in a new array modifier. Now we drive the empty rotation so that the result is always equally separated.
Set the array count to 10.
Add a Bezier curve, scale it. Add a Curve modifier to the other object, and set the curve as the target.
Let's shade this masterpiece ! (Easy part)
What the ?? Everything's white !
Let me show you the simplest magic trick in the book. Offset UV in the Array modifier.
Final result :
I'll let you play with the settings, not all the fun for me :)
In my opinion there is no need to create the actual geometry, since you may achieve the same effect (more or less) with normals and displacement (if you are using cycles microdisplacement will do the trick).
So I would start with a typical cylinder and I would use a seamless texture with stripes.
The trick is simply to rotate the texture, for few degrees
Just keep always in mind that there must be always a proper ratio between the rotation (degrees) and the thickness or the count of the stripes.
I would use a Bezier Curve, it's typically easier to create tunnel-like objects.
In the Object data properties, add a bit of depth to create the tunnel. Increase the preview resolution (number of subdivisions between each control point) and the bevel resolution.
Add a material, go in to the Shader Editor. The curves come in auto-UV unwrapped so we will be using the UV coordinates. Add a wave texture, and tweak the settings as you see fit. I used a Bright / Contrast node to incrase the contrast, you can also use a Color Ramp. Next for the bumpiness, I added a Math node set to Ping-Pong, at half value, so the light will reflect on dark rings as well as on bright rings. I added a RGB Curves node and smoothed the values, and plugged that into a Bump node, and finally into the Normal input of the Principled BSDF.
A little bit of distortion in the Wave texture is nice, but it add a visible seam in the texture.
Result :
To get the twirly effect, we will have to play a bit with the coordinates. Thankfully it is not too hard since the UVs are nicely mapped to to body of the curve. We will use the Y coordinate to offset the wave, creating the twirl.
First change the wave texture to be along the Y axis. We will offset the Y coordinate by a multiple of the X coordinate. You can play with it. I recommend starting at a low multiple and working your way up, else you won't see much happening.
The nodes :
Result :
