This is a technique for mapping complex shapes. Note that the tree does not match the mapping coordinates well at the surface of the model resulting in a serious texture stretching.
Add a noise map to the tree and set the texture to the UVW coordinate mode. Although noise is a program map that can be distributed in XYZ mode (which means that such a program map does not produce a texture stretch), a generic bitmap file needs to be positioned in a uvw manner (which produces stretching), so while using the noise program map, However, because of the use of UVW coordinate mode, it also produces the same mapping with the bitmap file stretching phenomenon. You can change the noise map in the source file to any bitmap file you like to observe the effect.
The advantage of this method of using a texture channel is that you can assign different types of mapping coordinates to different parts of a complex model, and then you can use a mask in a blend mix to determine which part of the model shows which texture channel's texture.
First, 4 UVW mapping are used, three of which are cylindrical, added to the trunk and two branches of the tree, and the other is planar and placed in the direction of the forward view. The number of the texture channels in the 4 modifier is then set to 1, 2, 3, and 4 respectively.
This picture shows the mapping coordinates with the channel number 2.
Now use a free plugin called Texporter, through the just set of the planar map coordinates to expand and output a UV line diagram. (In fact, directly with a unwrap UVW modifier will be UV editor in the UV-ray diagram of the box to copy down also completely, the effect is the same. )
Get the UV line diagram shown in the diagram.
Follow the diagram to make a mask in Photoshop, as shown in the following illustration.
Mask version 1
Mask version 2