After getting back into the rhythm of things, the Overgrown team continued each of their R&D.
I continued my research on L systems and mainly focused on two things.
Checking to make sure the geometry, the flower, buds, and leaves, would sit correctly in the L systems and grow as needed.
Using copy to points to place the vines.
First I added substitute geometry to check and make sure adding geometry would work. L systems typically have 3 geo inputs, JKM. Any geometry input can be placed inside the rules so it will be added to the L system.
The J in the rules, unless specified differently, indicate that the program must place the geometry that was in input J.
" is a multiplier and indicates as the generations increase, the size decrease so it looks as if it is growing out.
After I keyed the generation numbers to have the small vine grow. This was my first big hurdle. My first thought was to scatter points among the geo and copy the system to the points that were created from the scatter. It worked, but each of the l systems stood straight up and did not look correct. I wanted more variation of the placement of the offshoots as they naturally do not grow the same way. So, I needed to have them grow out of the direction of the base geo normal. I was able to use this as a guide to fit what I needed:
https://www.youtube.com/watch?v=plLOz96sdUo
I put down the normal node and used a pointvop to change the point into a position and output that attribute as a Cd as seen below:
After doing that I can use an attribute wrangle node to take the Cd attribute to tell Houdini that the density attribute is equivalent to the Cd attribute.
And finally under the scatter node I can turn on the density attribute check box so it uses that information to place the vines when it copies to points. Now it will grow based on the position of the normal rather than straight up. I tried to add some variants for the demo.
Going into the 5th week, I will mainly focus on adding the actual geometry that was given and work on growing the offshoots as the stalk of the grows and making sure the changes in mesh will not change the position on the stalk.