These fractals can both be drawn by emulating a pen: we keep track of the direction the pen is facing, and we can make the pen draw lines of a certain length in its current direction. We can turn the pen, and we can draw with the pen. These can be emulated with Transformations: turning applies a rotation to the pen's transformation, and drawing adds a translation (and the end point of the draw operation can be stored as an XYZ for creating line geometry later).
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Steellworks: Dynamo Fractals