As we headed into week 8, we were shooting to be around 95% by the end of the week. Xander was working on the flower materials, Emma was working on her particle renders and helping on lighting, and Hannah continued color grading and root process. I continued trying to find the best way to have interactive hand placement of the flower in shot 3.
After talking with the mentors and getting feedback on the best way of placing the flower in the palm, we talked about potentially trying vellum to not only place the flower, but to add softness to it. I have not had a ton of experience with vellum so I manly tried different techniques. Here are some of the tutorials that I looked at and dabbled on some of the discussions on the Sidefx page.
I manly focused on using strut vellum nodes in favor of geometry that was more solid, just softer.
As I started on my vellum journey, I was already having some issues with intersecting geometry as the flower needed to be placed in a certain position to make it look correct in the actress hand. Here are some flip books of some of my tests that I tried.
This was my first vellum shot with trying to get familiar with the node and to make sure the collision where going to work. The collision, the hand, was working, but the flower looks like a deflated balloon so we continued on.
Then I found the side fx Houdini vellum node tutorial where they went through all of the different type of vellum and the biggest differences between all of them. Strut felt like it was going to work for what we were going for. Strut calculates using points per constraints instead of volume. I checked their hip file for more information after watching the video and I wanted to see what the flower would look like with the same parameters as the demo, just to have a comparison and to see how different these setting affect different types of geometry.
This was the demo that sidefx provided
This is with the flower geometry.
Because of how thin the flower is, the vellum affects the flower a lot differently than the pig head. This was more of person test, because even as I tried tweaking the vellum to something that we were all happy with, I was still having some issues with, such as the stem crunching together even after building constraints.
These were the constraints that I painted. I did a couple more tests before hand with extreme constraints to see how it affected the geometry. I needed the middle of the of the stem to have a very rigid body while the ends can have some movement. My personal favorite thing that vellum was able to do was to make the strings in the middle of the flower move.
After testing multiple times and coming up to a deadline, I knew I could not learn vellum properly without it intersecting geometry and look off. I had to hand this off to be textured and composited. So I decided to cheat the vellum so it had some movement, but use copy to points to pin the flower to the hand. So it still had the movement and it would not be torn apart by the vellum.
For the vellum part of it, I turned off the gravity and had it move slightly, using force in the vellum as the driving variable.
This was what it looked like with the copy to points with the meta hand. It was subtle enough where it did not look unnatural, but it had some movement, but still rigid, like a flower.
I found a point with the a normal that would not flip in with movement in the inside of the hand. There was one point that I had originally tried that flipped and it would flip the geometry attached to it. So I grouped the single point with the correct normal and copied the flower to that specific point and it moves along with the hand.
These are the two final passes that I gave for the R&D slide of S9 meeting. First was the pass with the stem and one where the stem was booleaned out to see how it might looked with the correct root from our compositor Hannah.
Next week I will be finalizing the movement based on the team's and mentor's comments!