In this lesson video, we are going to discuss three special movement operations inside the edit mode, first is h sliding, second is vertex sliding, and third is moving along the normal direction are also known as string and in fact an operation we need to discuss these three techniques because we are going to use them in the upcoming lessons. First, let's discuss a sliding. A lot of times when we muddling we need to move an age or ages along the existing surface. This is what age sliding is all about. In this example, I have a tilted cylinder and a cube. Both of these measures are already joined together as a single object.

If we go to the Edit Mode, we have suffered edge loops at the center of the cylinder mesh. Now let's say you want to move this HMO so it is closer to the top area. We cannot use the existing access constraints, you can keep trying, but you will never get a perfect result. Even if you change this to the local orientation. Because the mesh is already tilted, there is no access constraint that can help us at the moment. In this scenario, the H sliding method is the best option that we have.

Essentially, it will slide ages on existing surface or topology. To access a sliding. First, make sure the age or ages are selected, go to the H menu and then choose h slide. Or you can simply right click and then choose a slide here. In this mode, we can slide the whole h low along the surface easily. Now, besides using the H menu, or the right click method, there is actually a hidden shortcut for the H slide operation.

And that is by pressing g twice. So press G and then g again. We can see we are sliding these ages. Okay. Another way to do h sliding is to use the H sliding tool, which is this tool here. If we have the tool active, we need to have the age or ages selected, then we can click and drag anywhere in the viewport to select the age.

Personally, I prefer to use the double g shortcut and just have the tool mode set to move or the selection tool. In certain scenarios, an age or ages can have multiple surfaces or faces connected to it. For example, this age at this cube mesh, if you want to slide this age, you can either Slide it this way along this face, or slide it this way along this face. blender is smart enough to detect our mouse cursor and decide which surface we actually want to align. So if you press g twice, you can see if I move the mouse cursor to this direction Blender will snap the age to the top surface. But if I move the mouse this way, the H will snap to the side face.

Another sliding feature that almost similar to the H sliding operation is the vertex sliding operation. Essentially, vertex sliding operation will slide a vertex along the existing ages connected to it. To do this, you need to be in a vertex selection mode. Let's say you want to slide this vertex, make sure the vertex is selected, then you can right click and choose slide vertices here, we can see how it automatically snaps to the age closest to the mouse cursor location. Because there are three ages connected to the vertex, you can pick which of these ages you want to snap to. For a vertex sliding, there are two shortcuts that you can use.

First is shift v. You can see the shortcut when you right Click or by going to the vertex menu up here and second is by pressing the G key twice, just like how we use the H sliding. Just like the H sliding operation. vertex sliding also has a dedicated tool. If you hold and press the vertex sliding tool, you will see the vertex sliding tool here. To use this tool, first, we need to have the vertex selected, then we can click and drag anywhere in the viewport to slide the vertex. The mouse movement will determine on which age you want to select the vertex.

The third technique we are going to discuss is the move along the normal direction are officially named as trimming and fatten operation. Let's say we select this face at the cylinder and we want to move the face this way along its normal direction. To do this, we can press ALT s and just move the mouse up and down. We can see how the face movement is constrained, but it's normal direction. If you forget the shortcut, you can open the mesh menu up here, transform, and then choose sharing fatten here, we can see the shortcut is alt s. Let me undo this. If we select this face loop and press ALT s, we can get something like this.

Now, at this point, you might be thinking that this operation is similar to the ordinary scale operation. My answer is, in certain scenarios, such as this one, they both might produce the same result, but the way they work is actually very different. For example, if I select this top face, and then press out, as we can see the face can extend or retract following its normal direction. But if we press S to do the ordinary scaling, this is what happens. It becomes bigger or smaller, instead of moving the face in a certain direction. So from this example, I hope you understand the difference.

Now, if you prefer to use the tool mode, you can access the sharing fatten tool, which is these two here. The workflow is basically the same with the other tools. First, you need to select the mesh elements. Then just click and drag the mouse up and down on the viewport drag down to shrink them and drag up to fatten them.