Hi everyone,
I have finished my very first 3D project ever (a cup). I have a jagged reflection of the emitting plane that the tutorial asked to insert in the scene (see image). Also the blue surface si jagged on the cup surface…
I have no idea how to fix this: I tried to change to options, used Branched Traced Tracing that seemed to allow some anti-aliasing, but nothing worked.
Nope. You haven’t attached an example .blend file and cropped the screenshot so it only shows the sampling settings. Clip indirect is too low, but otherwise, it’s likely not the sampling settings that causes the issue.
You’re using flat shading on the model, which basically treats every polygon as a little facet instead of smoothly interpolating the surface. Select the cup in Object mode and hit Shading > Smooth in the tool shelf (left-hand side menu).
Smooth shading option is on the tool shelf. This hides the edge between faces with shading. We don’t rely on subdivision surface to smooth out the model completely, it would require very high subdivision and would take a lot of resources.
Things that are not related to the jagged reflections but otherwise problematic:
Object scale is not 1,1,1, which means the object data (mesh) you edit doesn’t have the same dimensions you’re seeing in the viewport. Tools and modifiers use object data and they might appear as if they’re not working correctly. There’s also double geometry. Normals (vertex and face directions) seem to be consistent and pointing outside.
These are common things to do, in this order:
object mode, ctrl+A -> scale to apply object scale to object data. If nothing changes visually, it means it hadn’t caused a problem yet
edit mode, select all, W -> remove doubles to remove double geometry
edit mode, select all, ctrl+N to make normals consistent and pointing out
You can clean the jagged geometry on the mug bottom by selecting a face on both surfaces, ctrl+alt+shift+F to select linked flat faces which selects the rest, then inset (i) a bit. That creates support loop next to the perimeter which gives a clean subdivision.
Subdivision surface is not used to get smooth reflections, it’s used to add more geometry and smooth the contours of the model geometry which shading or textures won’t do. The more steep the curvature on a model, the more geometry it needs to look smooth, but that doesn’t automatically mean higher subdivision level.
Optimally model is built for specific subdivision level so that the density on the model is uniform and the chosen subdivision level is enough to smooth out the model contours. On yours the handle has a lot of control geometry so it doesn’t need any subdivisions along it, but does need around it. The mug itself has very little geometry to describe the rounded portions, so that needs even higher subdivision.
The result is that parts that don’t need high subdivision also get subdivided, and the model ends up with more geometry than it would otherwise.
Thanks for all the infos.
I think I had grasped some basic principle, above all the idea to design for specific subdivision level. This makes sense but - of course - that does not means I know how to do it.
Anyway I’m quite optimistic since Blender is the very first 3D app that does not totally confuse me and that I like (I tried a few).
I’ll go on with more tutorials
Thanks again!
That’s more than fine, you will later on. For now it’s enough that you know not to use too high subdivision level which would slow down your system/viewport. Keeping an eye on the density is something for further use.