Using falloffs in archvis
Recently, I was working on a project that required lots and lots of windows of different lengths, all of them divided into 2 or 3 equal segments. I figured, it would take a lot of time to fit every single window manually, and moving the center profiles by a fraction of the total movement to make the parts equally long. The situation looked something like the picture below. (Notice that I placed the Center-point into one corner of the window… thanks to this, it is easy to snap the corner of the window to a corner of the wall-opening even in item mode)
The idea was to use one of modo’s great features, the falloffs. Of course the linear falloff wouldn’t do, since I needed the shapes of the profiles and the handles to stay the same, and positioning the falloff for every new window again would be a lot of work as well. Luckily for me, the Vertex map falloff was ideal for this kind of task. What it does is to give every vertex a value in per cent, if you then make a transformation with the falloff and corresponding vertex map on, the transformation gets multiplied by the vertex map value for every single vertex (for example, we make a move transformation by 100mm in the X-axis, a vertex with a 100% vertex map gets moved by 100mm in the X-direction, 50% means a movement of 50mm in X, 250% means 250mm in the X-direction and -100% moves the vertex 100mm in the opposite direction). You can make the vertex map visible in the viewport by choosing it from the pie menu, that comes up by pressing ctrl+2 on your keyboard.
The color coding is easy to understand. Green means values near 0%, red means values near 100% and greater, the bluer it gets, the deeper you are in negative values. The next step is to create a new weight map, I called mine “weight falloff”, and now we can start to add values with the Edge weight tool (this is quite a useful tool, so I would recommend to add it to your custom pie menu, which you can easily create in the form editor)
We want the part furthest away from the Center-point to make the full movement, this means 100%. We can already see the color coding of the vertex map changing in the viewport.
The next profile is 2/3 along the window length and that is exactly how much it should move. To get the most accurate value possible, you can write 100/3*2 in the value field and modo will do the math for you!
Next is the profile 1/3 along the window length, entering 100/3 in the value field will do the trick.
And this is how the final product should look like with vertex map visibility turned on:
The next step will be to enable the correct falloff, which is Vertex Map:
To be completely accurate, select the Element action centre with Auto axis. This option allows you to snap the gizmo (tool handles) to any active geometry.
Since we want to snap the far profile of our window to the wall edge, enabling the Geometry snap option will be necessary:
Click on the Geometry you want the Tool handles to snap to (the vertex on the far side of the window from its Center point in our case) and move it to edge of our wall:
The yellow cube shows you the objects our transformation currently snaps to:
As you can see bellow, the window fits perfectly and the shape and thickness of our profiles as well as handles stayed the same. The nice thing about this kind of falloff is, that you don’t have to position it manually every time you want to use it and when you copy geometry and even whole items, the vertex map is copied as well.
This is it! I hope you liked this short… well, more of a tip than a tutorial, and that it might be useful to some of you one day.
If you liked this tutorial, you might want to check out part 2, where we improve the window even more!