The landscape

On the Terrain tab you open the Shape the terrain panel with . It holds the brush you shape the ground with. The panel is the brush: open it and you pick the brush up, close it and you put it down.

Choosing the brush

At the top of the panel is a list of what the brush does:

• Select, no painting — the brush off. Choose this to be able to click normally again.
• Raise / lower — ground on or off. The sign of the strength decides the direction: a positive strength raises, a negative one digs.
• Smooth — smooths what is there. The brush you come back to most.
• Flatten — makes everything as high as the spot where you began the stroke. That is how you make the flat strip for a yard.
• Trench — digs a channel with a flat bottom and steep sides.
• Noise — lays down small bumps, about a fifth of the brush across. For a surface that has become too smooth.
• Slope — not a stroke but one movement: press at the low point, drag to the high point and let go. An even slope appears between the two.

Setting the brush

Under it are the shape and two sliders: Radius and Strength.

The shape is round, square or speckled, or a greyscale picture you choose yourself. You also see that shape draped over the terrain as a blue shadow where your mouse is, so you always see exactly where you are about to paint.

Radius is the brush's radius in millimetres. Strength runs from −100 to 100 per cent and is not linear but rising, so that you can work finely at the bottom of the scale.

The brush works per second: hold the button down and it keeps painting as long as you hold it there. How fast your mouse reports therefore does not matter.

Painting

Hold the left button down and move. The camera leaves you alone meanwhile, so you can move freely; let go and the right button turns it again.

One stroke is one step in undo. However long you keep going with one button held, Ctrl + Z takes that whole stroke back in one go.

Close the panel, or choose Select, no painting, and TRAX puts the brush down. Esc does that too.

The ground does not have one colour but nine layers that run into each other: grass, sand, rock, gravel, earth, snow. Which lies where is partly decided by TRAX itself and partly painted by you.

The nine layers

The Terrain tab has Ground types. There are the nine layers, each with a picture and a name. Click the picture to choose another texture for it from the catalogue.

The first four layers have a fixed job:

• Layer 0 is the base: everywhere nothing else lies.
• Layer 1 is for the steep parts: rock faces and cuttings.
• Layer 2 is for the slopes.
• Layer 3 is for the high ground: the mountain tops.

Layers 4 to 8 have no fixed job. They are there for you to paint with.

Per layer you also set how big the texture is — how many millimetres one tile covers — and how it blends with the layer under it.

At the bottom of the window are the thresholds by which TRAX decides what is steep, what is a slope and what is high. Those thresholds are not hard: there is noise around them, so the borders wander instead of drawing a straight line.

Painting yourself

On the Terrain tab, open the Paint textures panel with . The panel is the brush: open it and you paint, close it and you stop. At the top are the tools:

• Paint texture lays the chosen layer down where you paint.
• Eraser: back to the automatic ground takes your own work away and puts that spot back to what the shape of the terrain prescribes.

Under them you choose which layer you paint with, and you set the radius and the strength. Only layers 4 to 8 are in it: the first four are decided by the shape, after all.

One stroke is again one step in undo.

There is no grass in it

The default set has no grass texture, and that is on purpose. Grass in TRAX is not a picture on the ground but real growth you put on it: tufts on crossed cards, moving in the wind. The ground under that grass is earth. See Grass and flowers.

When the set is applied

Change the set or the thresholds and TRAX works the three automatic layers out again from the shape of the ground as it stands now. What you painted yourself stays. Tables whose terrain is locked are left alone.

Fill in the terrain on the Terrain tab makes a landscape around your track in one go. That is usually the best beginning: have it filled in first, then work it over with the brush.

The first time

The first time you fill in the terrain, TRAX asks whether the terrain may move along from now on: under track you lay or raise, under roads and under buildings. Choose what you like. You can always change it later in the Settings panel, under Terrain, with Ground follows track and objects.

What happens

TRAX does it in three steps.

1. It looks at where the track is. Every piece's ballast bed is put on the grid as a footprint, at that piece's height, and with a note saying whether it is plain track, a tunnel or a bridge.
2. It measures the distances. For every point of the grid it works out how far it lies from plain track, from a tunnel and from a bridge — three separate measurements, so that no point jumps from one rule to another.
3. It lays down the landscape and fits it to the track.

The rules

• Under plain track the ground lies at the track's height, with a shoulder beside it, and then runs out into the landscape. Through a hill that becomes a cutting of about 34 degrees, across a dip an embankment.
• Over a tunnel at least twice the loading gauge of mountain is laid down, plus a tunnel wall, and it falls away at 1 in 2. That way the mountain reads as a mountain and not as a skin over the train.
• Under a bridge at least one gauge stays clear, it stays flat for another 250 millimetres past the deck and then climbs until it meets the landscape.
• Under a road the same rule as under plain track applies, with a maximum grade of 12 per cent.
• Under a building comes a flat plot.

The landscape itself

The landscape TRAX lays down is not noise. Noise gives random bumps at every scale, and a table of ten metres wants three or four hills with valleys between them, or a ridge. So they are real features: elongated hills with a length, a width, a heading and a height, whose headings are strung together so that they form ridges.

In the Settings panel you set the kind of landscape you want:

• Landscape: Rolling, Hills and valleys, or Mountains.
• Hilliness: how high, up to 3 metres.
• Feature size: how far apart the features lie.
• Detail: how much fine roughness goes over the top.

Choose a style and TRAX sets the other three to values that suit it. After that you are free to adjust them yourself.

The landscape is worked out in world coordinates with one random number for your whole layout. Two tables side by side therefore get one continuous landscape, and a table you add later matches its neighbours.

It takes a moment

On a big table filling in takes a few seconds. You see a progress bar; the editor keeps responding meanwhile.

The whole fill is one step in undo, for every table at once. If you do not like it, press Ctrl + Z and everything is back.

Flat again

Flat again takes a table's whole terrain away and makes it a board again. Tables whose terrain is locked are refused.