I did everything as in the tutorial
But when I deform the object I get this.
That’s because you are in Eevee (the material preview mode uses Eevee). The old version of Eevee in Blender 4.1 and earlier cannot do volumes in other shapes than a cube.
The new version of Eevee in Blender 4.2 (or Cycles) can do it.
Ok.
Cycles is too long for me and I have all the materials for eevee. My PC can’t handle blender 4.2
How to make volumetric light for weak pc?
I tried to do it through the world but it didn’t work
Those images look like it’s working, is this not what you are looking for?
Are you trying to get narrow light beams like in the tutorial? If yes, you can get them by placing the light some distance outside a window. You might also need to go to the render settings and increase the resolution of the volume (reduce the tile size) so it doesn’t look blocky.
But if you want to manually place them like in the video, there is a way. You need to first make the light beam straight, with no rotation, like this:
Once that works, then you can rotate the beam. It will work as long as you don’t apply the rotation. This also will only work if your beam is square or rectangle in shape.
It’s all about finding the right brightness for the light and the right density for the fog. You likely need a brighter light. Also, make sure your fog’s color is completely white. I do see the beam a little in your image, it just needs to be made stronger.
Also, make sure to give a bit of thickness to the wall, I can see light leaks at the bottom.
Is your floor at the default white color? If it is, you could try reducing its brightness. The default 0.8 is really bright and you would rarely see something this white in real life.
If you do volumetric light using fog, you get the realistic result, which means you can only get it to a realistic brightness. If you want brighter beams, you will need to do it the same way as in real life, and that could mean making the light brighter and darkening the rest of the scene to compensate.