# Are polygon normals really shadeable?

It made me wonder if such a problem could ever actually exist. Can polygon normals be shaded? Is a failure to do so detectable and reportable?

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This is actually an interesting question. – The Communist Duck Jun 17 '11 at 17:36
I'd love to know what causes this message because its kind of insane. – wangburger Jun 17 '11 at 17:39
The message wasn't a real error, it was an anti copy protection bit-tech.net/news/gaming/2011/04/13/… - A lot of people were banned from the official forums that day :) – Kevin van der Velden Jun 17 '11 at 17:47
@Yourdoom, yup. Keep in mind no one got their steam account or Gmod account banned. Only people who pirated the game had their account on the forum banned. There were 2 false positives in the first 30 minutes of the patch, but Garry checked their steam profiles(the error message contained their steam ID) and confirmed they did own GMOD. – AttackingHobo Jun 17 '11 at 17:52
I'm voting to close this question as off-topic because it's not about a game's error message. – Seth Battin Aug 9 '15 at 0:35

"Can a polygon normal be shaded" - No, a normal is a vector which is a 1-d object, so unless you're going to actually draw the normal and shade it, that statement doesn't make much sense.

However, shading polygons (2-d objects) commonly use the polygon normal in their shading calculations for light calculations to control how light or dark they can be.

So, I have no idea what that message is trying to say.

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-1 cause Normals are 3D objects, vectors, usually normalized and represent a line perpendicular to the surface they are associated with. The rest of the info us more or less accurate though. – James Jun 17 '11 at 23:43
I think you misunderstood what I was getting at. Any normal will appear as a 1-d object (line) since there is length only along 1 axis. Also, don't get stuck thinking that normals always have 3 components. – wangburger Jun 18 '11 at 0:54
1D is a point 2D is a line, normals are actually a 3D vector though representing the line perpendicular to the surface they are associated with ;) And due to computer hardware, most normals actually have 4 components but that does not really matter I suppose. Anywho, turns out the correct answer to this question is that people who see it pirated Gary's Mod... Sooo.. yeah :) – James Jun 20 '11 at 17:51

Normals in 3D graphics are a 3D vector indicating orientation or direction.

Normals themselves cannot be shades, as how can you shade {.1,0,.4} ?

Normals can be used to shade the polygons themselves. For example, a light source at a certain angle hitting a model made of polygons at a certain angle, the normals of the polygon faces can be used in the shading process to make the light make parts of the model brighter.

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+1 for good explanation of Normals. While I am not a person who has used Gary's mod, I would suggest that the message seen is a feature detection method stating they can not support normal map shading, either in general or for a specific object.. Again, just a guess though. – James Jun 17 '11 at 23:44