Geometry Nodes: Start point of the curve does not affected when using the Trim Curve node

Question

I'm using Proximity to change Z-position of the instances. Proximity is controlled by the Trim Curve node. The problem is that the start point of the curve is not affected. Is there a way to fix this with Trim Curve, or is there a more elegant solution?

Answer 1

The problem here is that you can only cover a part of the curve with your value for "Factor", because this runs from $0$ to $1$.

You can therefore solve this differently and with fewer nodes:

1. First use Capture Attribute at the very beginning of your node tree and capture the Curve Factor there.
2. After that, since this value will be transferred to all instances, subtract it from your input, which you multiply by $1.1$ before (so it will always be somewhere between $0$ and $1.1$).
3. Then map these values to the range you want, but limit the From Max value to $0.1$.

Since you previously multiplied the input by $1.1$, and now set $0.1$ as From Max, you will get a smooth transition in the range $0.1$. If you want to increase this transition, first multiply by $1.5$ and set From Max to $0.5$.

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