4.Filters

Basically, all filters are modifiers, that directly affect the base terrain shape. They can be combined with each other and further grouped into layers. Layers can be restricted to Areas, used to blend a specific region on the terrain. The filters that belong to a specific layer that have an area set up, are applied only along the areas’ blend map. Hence, you can use a combination of layers, filters and areas to create biomes (more on that later in another chapter).

Please note, that a blend map extends a mask by additional weight values per pixel. A traditional mask contains either black or white pixels whereas a blend map additionally encodes the weight for a given pixel – think of them like a gray-scale image.

General and Transform Filters

There are different kind of filters, such as direct transform filters, which will completely transform the base terrain shape into another kind of terrain type, such as Canyon, Desert, Terrace, as well as General Filters, that perform some generic operations or are used to create some additional noise or denoise.

Erosion and Sediment Filters

Another kind of filters are used to apply specific operations to an existing terrain, such as Erosion, Wind and Sedimentation. These filters can be found inside the Basic Erosion and Simulation category.

Design Filters

Also, there are so-called design filters, allowing you to create custom paths and shapes which can be used to further modify the terrain by hand.

Effect Filters

Another kind of filters that World Creator supports, are the effect filters. These kinds of filters allow you to apply special effects such as distortion, swirl, pixelate and more.

World Creator ships with tons of different filters that assist you to create unique and realistic terrain shapes for your needs.

Creating Filter Layers

To apply a filter, you first must create a layer by clicking on Add Layer. You can add as many layers as you want. With Remove All you remove all available layers.

Layers can be enabled, disabled, re-arranged, and, removed.

Each layer has a Name, an Area and a list of Filters. Naming a layer might be of interest if you plan a large and complex terrain. An area is used to specify a specific region using a blend map which is used to apply the filters of this layer to specific regions and with specific weights on the terrain.

Please note, that Layers in combination with Areas take an important role when it comes to create biomes. We suggest you take a close look at our tutorial videos which will show the creation of biomes step-by-step (see our web-site).

Adding Filters

Click on Add inside a selected layer, to open the Filter Library:

Each filter you select previews the result in real-time on the terrain. You may change the filter settings to see how it affects the terrain.

To add a filter, you either press Add or Add & Close. Add will just add the selected filter to the specified layer without closing the Filter Library. That way, you can keep on adding more and more filters. Add & Close will add the selected filter to the specified layer and close the Filter Library.

You can add as many filters as you want. But please keep in mind, the more filters you add, the more does World Creator have to compute to create the final terrain. Hence, you might experience a performance impact, if too many filters have been added.

Enabling and Re-Arranging Filters

Each filter can be enabled, disabled and re-arranged in its order. You may also Remove the filter entirely from the list. With Remove All you can remove all filters of the selected layer.

Change lets you exchange the selected filter to another that you can choose from the Filter Library.

Duplicate duplicates the selected filter.

Filter Properties

The filter properties are used to describe how a filter is applied to the terrain. Each filter has its own specific properties. The image below shows the properties of the Canyon filter.

You can click on the symbol to get a brief description of the current section. Every section inside World Creator has such a quick help button, serving you with a short documentation about the specific section.

With you can reset the settings of the specified section to the initial values. Almost every section has this option available.

Filter Distribution Properties

The filter distribution properties define at what specific locations the filter is applied. If an area is used, these properties only affect those locations that are covered by the blend map of the area. Else, the entire terrain is affected.

Operation

The Operation (Addition, Subtraction, Min and Max) lets you define how this filter is combined with the previous filter in the list. By default, Addition is selected.

Cavity

The Cavity is used to apply a filter either along the peaks (convexity) or along the carves (concavity).

Noise Select

If Noise Select is enabled, a Perlin Noise map is generated by the specified values. This map is then used to indicate at which locations the filter should be applied.

Height Select

With Height Select enabled, you can specify within what Height Range the filter is applied on the terrain, in meters

With Relative to Ocean, you can also offset the height range relative to the ocean height level (mean sea level). In a later chapter, you will see how to adjust the ocean height level.

Use the Height Smoothness values to adjust how softly or rapidly the filter’s effect is blended into the terrain at the lowest and highest values.

Slope Select

With Slope Select enabled, you also have the option to take the Slope Range and Slope Smoothness into account. With that, the selected filter will only be applied within the specified slope range, in degrees.

Angle Select

With Angle Select enabled, you also have the option to apply the filter along a specific Angle in degrees. Use the Angle Width and Angle Smoothness sliders to adjust the generation depending on the Angle.

Filter Level Step Strengths

The amount of available Level Step Strength sliders depends on the set resolution whereas the resolution is automatically calculated by World Creator depending on terrain size and precision. Hence, the larger the terrain size or precision, the more level steps are available for which you can control the strength values.

With that, the Level Step Strength sliders give you additional control about the smoothness per level and they do have a large effect on terrain granularity and shape, per filter.

Special: The Path Filter

The Path filter can be understood as a vector tool to create roads, streets, rivers, mountains or any other kind of form you can create with vectors.

A single Path filter can store an unlimited range of paths. Once the Path filter is applied, you need to click on Add Path to add a path.

If you want to name your path, simply enter a name in the Name field.

The Height Offset value can be used to offset the height of the entire path. You could use this to easily create rivers. Strength determines how strongly the path affects the surrounding terrain.

Width determines the width of your path, and Smoothness lets you smooth the path along its borders. With Segment Offset you can specify the number of segments used to create the path – the more segments you have, the more accurate it will be.

The Noise Scale can be used to change the noise values created along the path borders and the Noise Factor increases the noise weight – which is good when you are creating dirt tracks (e.g. Western style).

With Closed, you tell World Creator to close the path (connect first with last control point).

With Level Step you can control how accurate the path should be interpreted by World Creator. The higher the value, the more accurate it will be but the less options World Creator will have to mix its random content with the path. We suggest you quickly change the value in real-time mode to see the effect.

If Use Level Step is un-checked, you can control the strength per level. You will have more control on the mixing behavior as described above.

Each control point you add, can be scaled and moved on the terrain to design a path.

If Has Mesh is enabled, World Creator additionally creates a path mesh that can be either textured (Material = Standard) or it can be used as a water mesh (Material = Water).

This is only for visuals inside World Creator since you cannot export that mesh but export the paths’ blend map

There is an unlimited range of possibilities since Path filter is a multi-functional design tool. It is still under development and will be improved further, over time.

Special: The Shape Filter

Like the Path filter, the Shape filter allows you to create custom shapes instead of paths. With this filter you can create nice lakes, mountains, plateaus and more

As you can see, the available settings are very similar to the Path filter, except a few that are not available since they make no sense for the Shape filter (like Width and Segment Offset).

Once you click on Edit Shape, World Creator displays a default shape at the center of your terrain. You can add additional points to the shape by clicking on the dark grey spheres. With that you can create any kind of shape.

Move the shape by dragging it over the terrain and rotate a shape by pressing the right-mouse button outside the shape and moving your cursor.

You can remove points by holding down the Left-Shift and Left-CTRL keys on your keyboard and clicking on the sphere you want to remove.

There is an unlimited range of possibilities since Shape filter is a multi-functional design tool. It is still under development and will be improved over time.