Track Limits and Surfaces

Most racing games punish going off-line with a physics model: less grip, more slide, maybe a spin. Daily Dirt Rally does something blunter and, once you understand it, far more predictable. The dirt is walled in: its green edge stops your truck, which halts against it or slides along it. Beyond the road altogether your speed is capped, though a truck seldom gets out there.

The penalty, in numbers

On the dirt, your truck’s speed ceiling is 450 units. Hitting the green edge does not change that ceiling: the edge is a wall, so it stops you or slides you along it, and a nitro keeps burning. Only off the road, outside the track’s tiles, does the ceiling drop, to 60% of normal: 270 units. Nothing else changes there. Your steering authority, your braking and your acceleration curve are identical; you simply cannot go as fast.

A trip off the road costs you twice. You come back at the last spot where your truck was on the dirt, so the ground you covered out there is lost, and the time you spent there was at 270. Once back, the truck is up to full speed again within a fraction of a second.

Back on the road

You are never left stranded. After about three seconds pinned against a wall or another truck with the gas held, or two seconds off the road, you are put back on the road: at the last spot where your truck was on the dirt, facing along the track, at a standstill. Being pinned is the usual case; off the road is rare. Your truck is then see-through for a second, so nobody can hit it and it hits nobody while you get going again. A nitro still burning is gone; the canisters you carry are kept.

Pinned means getting almost nowhere, under 40 units a second, so a slide along a wall that is faster than that does not count, and nor does a hard corner. If you can see the way out, you need not wait: reverse out yourself.

Where the edge is

The boundary is not a rectangle around each track tile. Each of the sixteen track tiles ships with a 16×16 collision mask generated directly from its artwork: the tile is cut into 256 cells, about 22 units across, and a cell is drivable if its centre is on the dirt. The game tests your truck’s position against that mask. Dirt cells are drivable, grass cells are not.

Two consequences follow, and they are worth internalising:

• What you see is what you get. The ragged edge where dirt meets grass is the real boundary, give or take one cell. You can run the outside of a corner right up against the visual edge without penalty.
• It is a wall, not a run-off. Games that draw a wide verge and let you drive on it have trained a bad habit. Here the green edge is a wall you slide along: drive into it and the truck stops against it, or scrapes along it if you hit it at an angle, and the ground it would have covered is lost.

What this means for your line

Because the edge is a wall rather than a gradual loss of grip, the optimal line is more conservative than in most arcade racers. Three practical rules:

1. Never cut a corner across grass

The geometric saving from cutting an apex is a few truck lengths, and the grass will not give it to you: the green edge of the dirt stops the truck like a wall. Clip it and you scrape along it or stop against it; it is never a shortcut. This is the single biggest time loss for new drivers.

2. Sacrifice entry speed to protect exit

Running wide on exit is where most trips into the wall actually happen — you carried too much speed into the corner, the truck rotated too slowly, and the slide carried you into the outside edge. Braking a fraction earlier and turning in tighter keeps you off the wall and, because you never lose your speed against it, produces a better lap.

3. Use the full width, deliberately

Track tiles are 360 units across with the drivable corridor filling most of that, so there is real width to work with. Placing the truck on the outside of the corridor before a corner and unwinding to the inside gives you a straighter, faster path — and because the boundary follows the painted edge so closely, you can commit to using nearly all of it.

About the different surfaces

You will see references to asphalt, mud, sand and gravel around the project, and the track generator carries a full property table for them — grip coefficients, speed multipliers, colours. It is worth being straight about the current state of that system.

We would rather tell you that than publish a physics table you cannot feel in the car. If you have been trying to work out why the mud sections do not seem to slow you down, now you know: they are not mud yet.

Reading the daily track before you drive it

The front page publishes the day’s specs — checkpoint count, total distance and the surface distribution — before you enter the lobby. Because the layout is identical for everyone and fixed for the whole day, a minute spent looking at the shape of the circuit is a minute well spent. The track generation guide explains how the layout is built, which will tell you what shapes to expect.

Next, the part that turns a clean lap into a fast one: when to spend your three nitro canisters.