Slice

In the animation the guildhall will grow from the blueprints into the renovated model. To animate the building growing we will use a slice modifier and animate the slice plane.Other methods could be used such as moving the vertices that make up the model but as the model is quite complicated this would make it quite difficult to do it this way.

The slice modifier will be applied to the separate objects that make up the model so that they can be animated separately. All of the objects could be attached or grouped together and then the slice modifier applied but this would give less control over how the model can be animated.

I selected the attic part of the model, applied a slice modifier and selected remove top from the options on the modifier. By selecting remove top all of the model above the slice plane is removed, slicing through the model. When the slice plane is moved the the location where the model is sliced changes. This will allow slicing to be animated to create the building growing.

Slice

Using the slice modifier works well to create this effect but when the slice modifer cuts off the top of the model it leaves a hole where there are no polygons. To fix this a cap holes modifier can be added, this caps any holes in the model.

Cap holes

As a multi/sub object material is applied to the guildhall the material applied to the newly created faces is incorrect. To fix this a material modifier can be added, above the cap holes modifier, and then the material id set.

I also moved the uvw map modifier to the top of the modifier stack so that the materials would be mapped correctly onto the sliced object.

Material

Although this method seems to work well for many of the objects some of the more detailed objects such as the ground floor, first floor and chimney cause problems. With the chimney the cap holes modifer fills the hole in the top and with the building the model is incorrectly capped when the slice moves right near the top or bottom of the model.

The cap holes modifier works by selecting the border and then capping this hole. If an edit poly modifier is added above the slice modifier you can see that selecting the border and then selecting cap this creates the same effect. A way to solve this problem may be to remove the cap holes modifier on the objects that cause a problem and instead use an edit poly modifier and manually fill in the holes in the model by selecting the edges and then using the bridge tool.

Polygon created at the bottom of the model

The cap modifier also created a polygon at the base of the model even when the slice modifier was not applied. This was caused because there were no faces at the bottom of the walls, I fixed this by creating these faces around the bottom of the model.