I am using Blender 3.6.0. Apologies if my question wasn't clear. I am using Geometry Nodes to model and animate DNA and have figured out a pretty good node setup based on tutorials I've seen online. This essentially involves procedurally generating two helical curves around a parent curve. I will include an image of that node setup.

Now, I want to be able to unwind and unzip DNA in two directions. I have achieved this in the past by using stacked Curve Deform modifiers, allowing me to create a transcription bubble that opens in two directions. I have been able to animate this before on one axis by creating two helical curves (the curves that will be the DNA strands) that I deform using three Curve modifiers: two twisted curves that "pull" the DNA open, and one that deforms the DNA based on a "template: curve. When I animate the pulling curves moving away from each other, the DNA unwinds from the middle, opening in two directions. I was once able to use this method to create an animation I was satisfied with. I have not figured out a way to replicate this effect in geometry nodes because doing so usually involves only one curve meaning that I can only move the DNA in one direction.

My animation test: https://www.youtube.com/watch?v=EUgEo50dtY0

This method seemingly worked in my video because the helix was on a single axis. However, I run into trouble if I try to do this with a curve that isn't a straight line - the instances do not align as desired. If I use the same node tree I used in the first image, I can align the instances to the tangent of the deformed curves, but I cannot align the instances to rotate inward along the "template" curve like that of the first image. I cannot figure out the combination of vector, normal, position, and/or curve tangent nodes needed to get it to work and I cannot predict the behavior of the instances or why they aren't aligning like I want to. I will include an image of the Curve Modifier stack I used.

Is there any way I can achieve the effect depicted in my video with non-linear curves either using Curve Modifiers + Geometry Nodes or just Geometry Nodes alone? I would like to be able to have fully controllable DNA that I can unwind and unzipe using randomly-shaped curves to get a natural, dynamic look in animations. It would also be great if I could add "noise" or "randomness" to the single-stranded regions of the unwound DNA so I can animate DNA strands being threaded through enzymes as with DNA replication, transcription, etc. I will include the blend files of the correctly aligned DNA and the DNA that is giving me problems. My apologies if my question or the format of my post is unclear or messy, it's my first time and I'll do my best to clarify anything. Thank you!

"Wrong" DNA using Curve Modifier Stack + Geometry Nodes

I am using Blender 3.6.0. Apologies if my question wasn't clear. I am using Geometry Nodes to model and animate DNA and have figured out a great node setup thanks to Brady Johnston's wonderful tutorials for procedurally modeling DNA. This essentially involves procedurally generating two helical curves around a parent curve. I will include an image of that node setup.

Now, I want to be able to unwind and unzip DNA in two directions. I have achieved this in the past by using stacked Curve Deform modifiers, allowing me to create a transcription bubble that opens in two directions. I have been able to animate this before on one axis by creating two helical curves (the curves that will be the DNA strands) that I deform using three Curve modifiers: two twisted curves that "pull" the DNA open, and one that deforms the DNA based on a "template: curve. When I animate the pulling curves moving away from each other, the DNA unwinds from the middle, opening in two directions. I was once able to use this method to create an animation I was satisfied with. I have not figured out a way to replicate this effect in geometry nodes because doing so usually involves only one curve meaning that I can only move the DNA in one direction.

My animation test: https://www.youtube.com/watch?v=EUgEo50dtY0

This method seemingly worked in my video because the helix was on a single axis. However, I run into trouble if I try to do this with a curve that isn't a straight line - the instances do not align as desired. If I use the same node tree I used in the first image, I can align the instances to the tangent of the deformed curves, but I cannot align the instances to rotate inward along the "template" curve like that of the first image. I cannot figure out the combination of vector, normal, position, and/or curve tangent nodes needed to get it to work and I cannot predict the behavior of the instances or why they aren't aligning like I want to. I will include an image of the Curve Modifier stack I used.

Is there any way I can achieve the effect depicted in my video with non-linear curves either using Curve Modifiers + Geometry Nodes or just Geometry Nodes alone? I would like to be able to have fully controllable DNA that I can unwind and unzipe using randomly-shaped curves to get a natural, dynamic look in animations. It would also be great if I could add "noise" or "randomness" to the single-stranded regions of the unwound DNA so I can animate DNA strands being threaded through enzymes as with DNA replication, transcription, etc. I will include the blend files of the correctly aligned DNA and the DNA that is giving me problems. My apologies if my question or the format of my post is unclear or messy, it's my first time and I'll do my best to clarify anything. Thank you!

DNA with properly aligned instances using just Geometry Nodes and a single curve

"Wrong" DNA using Curve Modifier Stack + Geometry Nodes

I am using Blender 3.6.0. Apologies if my question wasn't clear. I am using Geometry Nodes to model and animate DNA and have figured out a pretty good node setup based on tutorials I've seen online. This essentially involves procedurally generating two helical curves around a parent curve. I will include an image of that node setup.

Now, I want to be able to unwind and unzip DNA in two directions. I have achieved this in the past by using stacked Curve Deform modifiers, allowing me to create a transcription bubble that opens in two directions. I have been able to animate this before on one axis by creating two helical curves (the curves that will be the DNA strands) that I deform using three Curve modifiers: two twisted curves that "pull" the DNA open, and one that deforms the DNA based on a "template: curve. When I animate the pulling curves moving away from each other, the DNA unwinds from the middle, opening in two directions. I was once able to use this method to create an animation I was satisfied with. I have not figured out a way to replicate this effect in geometry nodes because doing so usually involves only one curve meaning that I can only move the DNA in one direction.

My animation test: https://www.youtube.com/watch?v=EUgEo50dtY0

This method seemingly worked in my video because the helix was on a single axis. However, I run into trouble if I try to do this with a curve that isn't a straight line - the instances do not align as desired. If I use the same node tree I used in the first image, I can align the instances to the tangent of the deformed curves, but I cannot align the instances to rotate inward along the "template" curve like that of the first image. I cannot figure out the combination of vector, normal, position, and/or curve tangent nodes needed to get it to work and I cannot predict the behavior of the instances or why they aren't aligning like I want to. I will include an image of the Curve Modifier stack I used.

Is there any way I can achieve the effect depicted in my video with non-linear curves either using Curve Modifiers + Geometry Nodes or just Geometry Nodes alone? I would like to be able to have fully controllable DNA that I can unwind and unzipe using randomly-shaped curves to get a natural, dynamic look in animations. It would also be great if I could add "noise" or "randomness" to the single-stranded regions of the unwound DNA so I can animate DNA strands being threaded through enzymes as with DNA replication, transcription, etc. I will include the blend files of the correctly aligned DNA and the DNA that is giving me problems. My apologies if my question or the format of my post is unclear or messy, it's my first time and I'll do my best to clarify anything. Thank you!

I am using Blender 3.6.0. Apologies if my question wasn't clear. I am using Geometry Nodes to model and animate DNA and have figured out a pretty good node setup based on tutorials I've seen online. This essentially involves procedurally generating two helical curves around a parent curve. I will include an image of that node setup.

Now, I want to be able to unwind and unzip DNA in two directions. I have achieved this in the past by using stacked Curve Deform modifiers, allowing me to create a transcription bubble that opens in two directions. I have been able to animate this before on one axis by creating two helical curves (the curves that will be the DNA strands) that I deform using three Curve modifiers: two twisted curves that "pull" the DNA open, and one that deforms the DNA based on a "template: curve. When I animate the pulling curves moving away from each other, the DNA unwinds from the middle, opening in two directions. I was once able to use this method to create an animation I was satisfied with. I have not figured out a way to replicate this effect in geometry nodes because doing so usually involves only one curve meaning that I can only move the DNA in one direction.

My animation test: https://www.youtube.com/watch?v=EUgEo50dtY0

This method seemingly worked in my video because the helix was on a single axis. However, I run into trouble if I try to do this with a curve that isn't a straight line - the instances do not align as desired. If I use the same node tree I used in the first image, I can align the instances to the tangent of the deformed curves, but I cannot align the instances to rotate inward along the "template" curve like that of the first image. I cannot figure out the combination of vector, normal, position, and/or curve tangent nodes needed to get it to work and I cannot predict the behavior of the instances or why they aren't aligning like I want to. I will include an image of the Curve Modifier stack I used.

Is there any way I can achieve the effect depicted in my video with non-linear curves either using Curve Modifiers + Geometry Nodes or just Geometry Nodes alone? I would like to be able to have fully controllable DNA that I can unwind and unzipe using randomly-shaped curves to get a natural, dynamic look in animations. It would also be great if I could add "noise" or "randomness" to the single-stranded regions of the unwound DNA so I can animate DNA strands being threaded through enzymes as with DNA replication, transcription, etc. I will include the blend files of the correctly aligned DNA and the DNA that is giving me problems. My apologies if my question or the format of my post is unclear or messy, it's my first time and I'll do my best to clarify anything. Thank you!

"Wrong" DNA using Curve Modifier Stack + Geometry Nodes