I tried to offset surface edge 1m to outside (which is pretty simple).
I used offset curve component but outcome is not what I expected as shown below(green one in rhino screen).
Does anyone know what is the reason and how to fix this problem?
File?
Please find attached rhino&gh
offset.gh (1.9 KB)
offset.3dm (41.9 KB)
Your input offset distance is too big for inward offsetting .
If you want to offset toward outside, Use negative value.
I see!
May I ask you which attribute in input surface is defining offset direction?
coz when I tried offset for other surface which is generated in same process offset outward as shown below.
You can change offset direction by using positive or negative number.
Understand that point. What I want to ask you is that even though I use same number (say, positive number), one case offset inward (first picture) and once case offset outward (second picture). I check the surface normal direction but both are same. Do you have any idea what attribute in input surface is defining offset direction?
I check the surface normal direction but both are same. Do you have any idea what attribute in input surface is defining offset direction?
Surface normals have nothing much to do with it. Offset looks at winding direction I believe (same how curve offsets look at direction) which is orientation in Rhino space. Like what edge is your U and what is your V and which way are these edges pointing. You can look at and edit that stuff in Rhino with the Dir command. In Grasshopper you can use the Swap UV component from Pufferfish.
I am not saying this is the way it should be (maybe there should be a better way to determine in or out) but it is the way it is.
If it is a surface edge you could try the Offset On Surface component which should always offset inward onto the surface.
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Thank you for teaching me that.
I tried to offset the outline to inward direction.
However, it behave not as I expected as shown below.
May I know what is causing this problem and how to solve this?
offset2.3dm (36.2 KB) offset2.gh (2.9 KB)
Offsets are just not great in GH natively. What you are seeing there is the result of a failed offset because your distance was too big for that corner. You should download and use Clipper which can easily resolve the offsets.
P.S. you don’t need to attach grasshopper and rhino file. Just internalize you rhino geometry into the gh file (right click the curve param and select internalize). Then you can just upload the grasshopper file.
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I tried clipper / polyline offset but didnt work as I expected.
Could you help me to sort out this?
offset3.gh (4.8 KB)
