Transfer Attributes with Normal Direction

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How can I transfer attributes from a normal direction. For example, if I draw a line on a grid and have the normals pointing off to one side of the line, then how can I tranfer attributes from the line to the grid on the side that the normals are facing? I hope that makes sense, I've attached an image as an example. I'm thinking maybe a dot product?

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Dot product would be a great start. I would generate a mask or a group using the dot product then drive your attribute transfer from that.
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Hi,

You can create a mask using the dot product and then use that mask after attribute transfer to tweak the result:

Mask by Normal (Point Wrangle):
vector n = normalize ( @P - v@pos );
float d = dot ( n, normalize ( v@dir ) );
@mask = fit ( d, ch("min"), ch("max"), 0, 1 );

Apply Mask (Point Wrangle):
@near *= @mask;

near pos (Point Wrangle):
@near = 1;
v@pos = @P;

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