week 7 - tree growth 2
/// Tree Growth Final Approach ///
After weeks of thinking, I came up with an idea to solve the tree growth problem. Remember how I extracted the tree’s centerline in Week 4? If we move all the points along the centerline and then return them to their original positions from bottom to top, we’ll get a growth animation. Then we can add a soft-body simulation to make it look more like a living plant.
/// Splat Tree Swing ///
Use Vellum Solver to create the swing animation.
Use Guide Deform to apply swing animation from primitive(the center line) to polygon. Then use the Point Deform node to apply the deformation. For some reason, Point Deform seems to be more stable than Splat Deform here.
/// Splat Tree Growth Completion ///
To create the growth animation, the key is using Carve to generate an animation of line growth, use this as a mask, and transfer it to the splat model. Then, use another Carve to generate an animation of point movement, which serves as the starting point for all points and changes position as the mask changes.
Use the Attribute Adjust Vector to override the attribute, which allows it to transform the old attribute (growth line points) into the new attribute (splat points). Since my centerline does not lie exactly in the middle of the model, this may cause some points to grow from slightly offset positions during the growth process. This is particularly evident in the form of discontinuities and unconnected points that appear during growth. For overly complex models, this is likely unavoidable.
/// Color Correction///
One weird thing is that the splat imported via GSOPs causes significant color discrepancies. I didn’t notice this until the rendering stage. The solution is quite simple: after importing the splat model via the “File” command, simply assign all its properties to the model imported via GSOPs to override them.
/// Next Plan ///
1. Refine the destruction scene
2. Try Houdini-22 new GS feature
3. Start Statue of Liberty shot