Transport Tycoon Forums

I've been looking at the source code to figure out how fast are vehicles (trains) in the game actually moving. The wiki says that a train moving at 100mph travels 5.6 tile per day. In source codes I found this:

1. Train::UpdateSpeed in train_cmp.cpp says that a train can travel 3/4 cur_speed every tick.
2. TrainLocoHandler in train_cmp.cpp advances the train one pixel for each 192 accumulated speed (assuming the train is moving parallel to the gridlines).
3. TileVirtXY in map_func.h suggests that one tile is 16 pixels wide.

Now assuming there are 74 ticks in one day, a train travelling at speed 160 (which corresponds to 100mph right?) should move (74*3/4*160)/192/16 = 2.89 tiles per day. Could anyone point out what part(s) of this calculation is(are) wrong?

afair, trains move twice every tick, not sure how that affects your calculation, though.

To find out how fast they are *actually* moving I would count the number of pixels they travel per second. Because they are usually moving diagonally, you may need some help from our friend pythagoras

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Aha! Thanks Eddi. So does that mean that the train would move 5.78 tiles / day? Why does wiki mention 5.6?

andythenorth wrote:To find out how fast they are *actually* moving I would count the number of pixels they travel per second. Because they are usually moving diagonally, you may need some help from our friend pythagoras

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Except classical geometry doesn't really work in TTD land. TTD's squares are actually circles.

*brain explodes*

Squares don't look like squares in OTTD, you have to use diamonds instead.

If we need a diamond, we usually just tape a bunch of triangles together.

audigex wrote:Squares don't look like squares in OTTD, you have to use diamonds instead.

If we need a diamond, we usually just tape a bunch of triangles together.

They're not squares or diamonds.

Check out how many regular-length train vehicles fit on a tile in each of the 4 orientations...

haha I know - but I refused to miss an opportunity to paraphrase a simpsons quote.