I’m Ayana, a Vtuber
Today I will explain how to use UV Mapping
Let’s create an object like this by UV mapping!
What is a UV map?
[UV map] is a development view of an object. As shown here, the expanded cube is the [UV map] of the cube object.
About UV editor
The UV Editor panel is where you can view and edit UV maps.
This is the [UV Editor].
You can also switch from the workspace. This [UV Editing] is a workspace suitable for editing UV maps.
As shown here, only the part of the face selected in [Edit Mode] is displayed in [UV Editor]. To view the entire UV map, you need to switch [3D Viewport] to [Edit Mode] and press A to select all.
Please note that it is common for beginners to not see the UV map despite UV unfolding!
Blender’s standard objects, such as Cube and UV Sphere, already have UV maps.
Let’s check the [UV map] that the object has.
①Look at the item called [UV Map] from [Object Data Properties] in the [Properties] panel. This [UVMap] is the name of the UV map that the object has.
② You can check the [UV map] displayed in the [UV editor] from here.
This red line is called [Seam]. It will be a cut line when unwraping.
Please note that it is required when unwraping.
① Select the edge to be set as a seam.
②Select [Edge]> [Mark Seam] to set the seam.
Now that the [Seam] setting is complete, let’s expand it
① Press A to select all meshes. Please note that this operation is easy to forget!
②Select [UV]> [Unwrap].
Then, the [UV map] is created like this.
Smart UV project
[Smart UV Project] automatically develops UV without setting [Seam].
Select all meshes with the A key and choose UV> Smart UV Projection.
① [Angle limit] makes it impossible to set [Seam] for edge below the set angle.
② Click the [OK] button.
Unwraping has completed ! It is convenient because it automatically unwraps UV.
UV map editing
Before creating the image texture, edit the UV Map to shape it.
This is the [UV Editor].
The operation of [UV Editor] is almost the same as the operation of [Edit Mode] of [3D Viewport]. Let’s see how it is!
UV selection mode
First, about [UV selection mode]. Similar to [3D Viewport], there are vertex selection mode, edge selection mode, and face selection mode. Here we will have a new mode that is Island and I will explaine it later.
This is the vertex selection mode.
This is the edge selection mode.
This is the face selection mode.
Next, I will explain [Island selection mode]. When unwrapping UV, depending on the seam settings, the UV map can be split into two parts.
Each of these separate UV maps is called an [island].
This is the switching button of [Island selection mode].
in [Island selection mode], you can select [Island] like this.
Use T to show / hide [Tool Shelf].
The operation with Box Select here is the same as the operation for [3D viewport].
Move / rotate / scale
Moving / rotating / scaling is exactly the same as the operation of [3D Viewport].
Press G to move.
Press R to rotate.
Press S to scale.
If the vertices are messed up like this, let’s [Align] it.
Select multiple vertices and choose UV> Align> Align X.
In this way, the positions of the vertices are aligned with respect to the X-axis. If you want the vertices to be aligned with respect to the Y-axis, select Align Y.
By setting the pin to the vertex, you can keep the vertex fixed when UV unwrapping again.
Let’s Fix the vertices of this face.
Choose UV> Pin.
These four red dots are called Pin.
Let’s unwrap again.
It was unwraped with the pins fixed in this way.
To Check how it is mapped while editing the [UV Map].
Use [Color Grid] to check the mapping. I have already explained how to apply [Color Grid] in the previous lecture.
Set the [3D Viewport] display to [Material Preview] so that the material is displayed.
You can check the mapping like this. Adjust so that the size of the color grid is constant. If the grid is too large, the image will be rough when applying the image texture.
Two image texture creation methods
I will create an image texture from here, but there are two ways to create it, one is to use the internal functions of Blender and the other is to use external software such as Photoshop.
About how to use the available features of Blender, I will explain in detail next time.
This time, we will create an image texture by using external software!
After you have created a [UV map], export [UV map] so you can create another texture for it with external software such as Photoshop.
From the UV Editor, select UV> Export UV Layout.
①Set the size and fill opacity.
② Change the name.
③ Click [Export UV Layout] to export.
An image like this will be exported.
Next, let’s create an image texture in Photoshop.
I will create an image texture like this
Then we will just export the texture file, don’t mistake it with the UV Map export
Now, let’s map the created texture to the object.
Open the Shader Editor. Add an Image Texture node and build such a node like this.
Press the [Open] button in the [Image Texture] node.
① Select the created texture.
② Click [Open Image].
Set the mapping by Adding [Texture Coordinates] node and [Mapping] node, and connect the nodes like this.
The output of the Texture Coordinates node is UV.
The texture mapping is done!
This is completed!
This is the end of the lecture on how to use UV mapping .
How is everyone doing?
Did you understand today’s lecture?
See you again for the next lecture!
See you soon! Bye bye!