The purpose
It smooths the object’s shadows, making them look more natural.
Environment
Blender：3.4.1
Use smooth shade
In the top-left corner of the screen, switch to Object Mode.
Click to select the desired object.
Right-click and choose Smooth Shading.
To revert to the normal shaded view, right-click the target object while it’s selected and choose Flat Shade.
Result
Before:
After:
Comparing before and after, the edges in the revised version are less noticeable and appear more natural.
For your information
Impact of settings
Smooth shading/flat shading can be set per object.
Therefore, you can arrange objects with different smooth/flat shading in a single project, as shown below.
When you add an object, it’s initially flat-shaded. To use it with smooth shading, you need to change its shading setting each time. (Multiple objects can be selected and changed at once.)
ICO sphere/UV sphere
We’ll compare the results of applying smooth shading and flat shading to both an Icosphere and a UV sphere. With smooth shading applied to the Icosphere, the polygon count is low, and the object appears smooth internally. However, the edges remain jagged. Applying smooth shading to a UV sphere results in a nearly polygon-free appearance (although this depends on the UV sphere’s polygon count and settings).
upper side: flat shade
down side: smooth shade
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