3ds max Polygon Modeling Preparing Boolean operands And so I can't tell where I need to cut, and there's a little trick for this, what you can do is select your object, and go into the object properties, right-click, choose object properties, and in here we can enable see-through for the object. And in my case, I am not inheriting the properties of the enclosing layer. If you see this is all grayed out, and it says by layer here, then you can click that by layer button and then get to these options for the current object. Okay, so click OK, and with see-through enabled now it's displayed in gray, and I can just barely see where the line on my image plane is. And that's where I want to create the box. Right, so I'll go into the create panel, to box, and I want to snap in 3D, to the existing grid points. Get in close there. Click and drag, holding down the left mouse button, and then simultaneously hold down the middle mouse button, and drag. And keep doing that, just release the middle mouse, and then drag, and then click the middle mouse again. But holding down the left mouse button the entire time. And then when we get over here to the other side, release the mouse, and drag, and you'll see in the create panel that the height is changing. It doesn't matter what the height is just now, we just click to complete the operation and that box has been built, and then right-click to exit creation mode. Go back to the perspective view with alt-w. And then zoom in with z, and there's our box, and we need it to be a lot taller, I want the door to be 200 centimeters in height, that's about six and a half feet. And with that object selected, the box, go into the modify panel, and I can set the height to 200 centimeters. And the width here doesn't really matter, because that's the thickness of the hole, so I can increase that, but as long as it is thicker than the object we're trying to cut, then everything is fine. But there is one little issue here at the bottom, we will have a coincident situation here, where the polygon of the cutting box is right on top of the polygon for the object we want to cut, which is the wall.
