Adjusting Vehicle Speeds

[Smit_h_y]

OK so with TTDPatch i was able to use Rudge's TTDAlter to adjust most things about the game. Is there something similar to this for OTTD?
ta

[DaleStan]

Yes. Newgrf.
Or the source.

[Smit_h_y]

er...

[AlexH.]

In easier words, DaleStan said that there are no programs that can edit vehicle stats in way similar to TTDAlter one. You can modify vehicles by creating NewGRF files that could alter or overwrite specs or modify directly the Source

[Miranda]

I modified the source and Rebuilt it so trains are always max speed no matter if they come to a hill bridge depot or anything. I only did it to trains cus I dont care for busses etc, not sure if im allowed to post my game here though

[Grolsch]

I modified the source and Rebuilt it so trains are always max speed no matter if they come to a hill bridge depot or anything. I only did it to trains cus I dont care for busses etc, not sure if im allowed to post my game here though

where can you change the code to do that? i found the place where i can alter the vehicle speed, but not where the curve/slope slow is located...

[Smit_h_y]

are there any complete tutorials on going about editing the source?

[Grolsch]

I know that here is explained how to compile the source. If you have the source, and some knowledge of programming, it should be doable. However, I have no knowledge of it, and am proud to have found a way to adjust trainspeeds

[Campmaster]

I modified the source and Rebuilt it so trains are always max speed no matter if they come to a hill bridge depot or anything. I only did it to trains cus I dont care for busses etc, not sure if im allowed to post my game here though

where can you change the code to do that? i found the place where i can alter the vehicle speed, but not where the curve/slope slow is located...

I don't have a compiler at hands now but in train_cmd.c you can find the function UpdateTrainSpeed:
Replace

Code: Select all

v->cur_speed = spd = clamp(v->cur_speed + ((int)spd >> 8), 0, tempmax);

with

Code: Select all

v->cur_speed = spd = tempmax;

and your trains should always travel at max speed

As I have no compiler at hands I can't test if it actually will work but I'm quite sure of it. Personally I'd prefer to change some lines above the quoted one from "accel * 2" to "accel * 200" which means your trains will reach full speed 100 times faster which is almost like instant full speed but you can still see them accelerate if you watch them ingame. (I think instant full speed looks more unrealistic then the 100 times faster acceleration).

PS: Trainspeeds are located in table\engines.h
Look for "const RailVehicleInfo const RailVehicleInfo orig_rail_vehicle_info". The struct is well documented - you should be able to find the max-speed-column.

[Smit_h_y]

ok so i decided to take the Newgrf route. Isnt too taxing i can see but i have a question;
If all i am changing about a train is its speed/power etc, then is it still necessary to have an action1 line? Also does that mean i dont have to define its sprite for each view?

[peter1138]

If you're not changing the graphics, then you only need the Action 0s

[Smit_h_y]

thanks thats a relief.

Oh one more question;
At the bottom of this page, theres an example of an action 0 line for a train engine. The value given for the speed property is 'C0 00', this is supposed to represent 192, but i cant see how. The other bytes seem to follow some sort of conversion like str -> hex or whatever, but i cant see how that got that as a value. Kind of stuffs me up if i want to go about changing the speed and i dont even know what value i should be using

[MacLir]

If you're using WinXP (not sure on older versions, its been too long ), the caculator 'accessory' can convert the numbers from decimal to hex. Just click on the 'View' menu and change it to 'Scientific' and the displayed window will expand.

[Smit_h_y]

ok nevermind, i just forgot to convert the hex into little-endian

Sweet, now i have created my first NewGRF, thanks guys

By the way, does anyone know the max speed i can set the trains at? Or any vehicles for that matter now that im on a roll...

[DaleStan]

The largest value that fits in the given width.

[Smit_h_y]

OK so i got to increasing the trains max speed and hp. Checked it in game and all works well, apart from the trains will never reach that speed because of acceleration, and i found nothing in the wiki of action 0 properties for trains about acceleration.

[DaleStan]

Power, weight, coef. of TE, and coef. of air drag.

[Smit_h_y]

gotcha, but its still taking its time accelerating. Think im gonna have to change weight etc for Wagons and Cargo's...

[Smit_h_y]

hmm, if the <Num-info> element is greater than 1, do i then go to list the vehicles in the <ID> element one after the other? i.e.

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4 * 10 00 00 01 04 59 5A 5B 5C 16 00

Or is it done like counting fron one to the next inside 2 given values. i.e

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4 * 8 00 00 01 11 59 63 16 00

Where <Num-info> is 11, and there are 11 vehicles from 59 to 63.

[DaleStan]

hmm, if the <Num-info> element is greater than 1, do i then go to list the vehicles in the <ID> element one after the other?

No. Only the first vehicle's ID. The other vehicles (if any) are the ones with the next sequential ID(s).

there are 11 vehicles from 59 to 63.

No, there aren't. There are 0B. There are 11 from 59 to 69.
Don't mix your bases.