Added the ShapeGrammar geometry node.

README.md

@@ -207,6 +207,22 @@ support the asset workflow.
 
 > A node, that mimics blender's native z-Up curve orientation by calculating the corresponding tilt angles.
 
+### [ShapeGrammar](geoNodes/shapeGrammar.blend) (Blender 4.0)
+
+<img src="geoNodes/shapeGrammar.png" height=200 />
+
+> A geometry node, that takes a grammar rule as input (e.g. "AB?(CB)*A") together with a collection and a curve
+> instances respective elements from the collection onto the curve. Rules are the following:
+> * A-Z : references a geometry from the collection (A=first geometry, B=second, C=third, ...)
+> * (...): groups elements together
+> * ?: Marks a geometry or group as optional
+> * *: Marks a geometry or group as repeatable
+>
+> For example the grammar from above ("AB?(CB)*A") can be expanded to a length of 9 in the following way:
+> ABCBCBCBA
+>
+> So the resulting geometry is framed by instances of A, while inside instances of B and C alternate.
+
 ### [StringToField](geoNodes/patternResample.blend) (Blender 3.5)
 
 <img src="geoNodes/stringToField.webp" height=200/>

geoNodes/shapeGrammar.svg

@@ -0,0 +1,92 @@
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