Creating Procedural Buildings in Ürban PAD¶
The first Ürban PAD versions introduced the concept of procedural building creation through the Vertical Line operation. These procedural building capacities were significantly enhanced in Ürban PAD 2.5 with new procedural buildings functionalities available in Sector Editor.
Why Procedural Buildings?¶
The first Ürban PAD versions introduced the idea of procedural buildings with the Vertical Line operator (see Creating Procedural Buildings). This basic Parcel Editor operation allowed randomized stacking of building levels in order to make a building template whose appearance would change with each regeneration.
Creation of city blocks, however, remained difficult with Vertical Line.
Versions beginning with Ürban PAD 2.5 extend Vertical Line’s randomizing functionality with a range of Sector Editor capabilities. Sector Editor can be used to create procedural buildings, or a block of procedural buildings.
Procedural buildings created in Sector Editor differ from procedural buildings created with Vertical Line in Parcel Editor in the following ways:
- A parcel created in Parcel Editor has a fixed size and shape.
- Procedural buildings created in Sector Editor have no fixed size or shape. They are procedural volumes that can be reshaped and resized at will.
- Parcels created in Parcel Editor consist of a combination of assets expanded on a surface.
- Procedural volumes are created with rules (see A Word About Rules, Targets, and Layers) and represented as layers in the layers window. Meshes and textures can then be applied to these layers.
- Parcels can be added to a city specification (see City Designer: Creating a City Specification) as activities (see Activities and Influences).
- Sectors cannot be directly added to a city specification as activities. They must first be imported to a parcel through a Sector Link (see Composability and Activities).
Procedural buildings created with Ürban PAD 2.5 share the following characteristics:
- Assets are imported and converted to .egg format (see Mesh Converter) and transformed procedurally.
- Asset appearance is randomized through application of rules: transformations, decorations, tags, and context.
- Sector and Parcel linking capacities allow cross-linking of parcel and sector elements between Sector and Parcel Editors (for information on why this is useful, see Composability and Activities).
A Word About Rules, Targets, and Layers¶
Rules form the basis of sector creation in Sector Editor. A rule is a transformation, decoration, tag, or context applied to an object. A rule can be simple or complex. For example:
- You can use the Split Y operation to divide a building wall mesh once, horizontally
- You can use the Random Repeat Split Y operation to divide a building wall mesh repeatedly, horizontally, at randomized and regular intervals
Rules are used to create the sector specification, or the description of the sector that is saved as a .gcf file. A sector specification is comparable to the parcel specification that is created for each parcel in the Layers window of Parcel Editor.
Each operation, or application of a rule, in Sector Editor creates a layer.
A layer to which a rule is applied is a target. You will need to name layers and targets as you work. Giving each layer and target a name that is easy to identify and coherent with your building will make it easier to correctly name future targets and follow the progression of your work.
Adding a new rule¶
You may add rules to the tree by one of two methods:
- Select a face in the View window. Selecting a face opens the New Rule menu and gives a choice of layers accessible from the one you have clicked. From this menu, you may then click on the correct layer, and the rules available for this layer will be displayed below the layer selected.
- Right click the Rules menu in the tree to access rule menus and add rules. You will be required to enter your target manually.
It is highly recommended that you use the first method whenever a layer can be selected in View mode.
Creating Procedural Buildings 1: Tutorial Objectives¶
In this 3-minute video tutorial, you will learn how to use Sector Editor to:
- Create a basic building shape
- Texturize the building
- Create a ground floor for the building
- Divide the building into floors
- Add windows to all faces of the building
- Add a door to the ground floor
- Display the final building with a variety of View options
Creating Procedural Buildings 2: Tutorial Objectives¶
In this 3-minute video tutorial, you will learn how to use Sector Editor to:
- Create a block shape
- Split the block into different placement points for buildings
- Create a sector link to the building created in Creating Procedural Buildings 1
- Regenerate and display the final building
Beginning the Tutorials¶
To begin these tutorials, open the Ocean Isle city project that you downloaded with your trial version of Ürban PAD and click the Sector Editor tab to access the Sector Editor interface. :ref:`
Sector Editor’s interface is divided into three parts:
- Rule Tree: add rules by right-clicking Rules and adding a rule from the menus. You will have to type in the target name.
- New Rule: select a layer in the View window to choose a target from a dropdown box and affect an operation to it.
