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[McCoy]

There's any way to do trigonometric operations in WME, or I need an external DLL? I'm gonna do an small mini-game for my game, that need physics, so I need some trig...  

[Mnemonic]

No, there are currently no built-in trigonometry functions in WME.

[Jerrot]

Just wanted to check this out - can anybody tell me, what's wrong ?

C++:

Code: [Select]

#include <math.h>

extern "C" __declspec(dllexport) double xSin(double mynumber)
{
   return sin(mynumber);
}
WME:

Code: [Select]

external "trigonometry.dll" cdecl xSin(double);
actor.Talk(xSin(90));
As always I'm not sure about the var types. I also tried to replace the "double" in the WME script by "float", "int", "string", ... no errors, but the same result: "[null]". Why ?!

[Mnemonic]

You forgot to specify a return type of the function.

Code: [Select]

external "trigonometry.dll" cdecl double xSin(double);

If you don't specify the return type, WME assumes no return value.

Otherwise your function works pretty good :-)

[Jerrot]

You forgot to specify a return type of the function.

*duh!* thank you!

Anyway there is something strange - maybe I just forgot everything about maths, but I can't believe it. I created a "trigonometry.dll" with some functions from math.h as mentioned above. To be sure I made no mistake, here is the C code again:

Code: [Select]

extern "C" __declspec(dllexport) double  math_sin(double mynumber)
{
  return sin(mynumber);
}
extern "C" __declspec(dllexport) double  math_cos(double mynumber)
{
  return cos(mynumber);
}
extern "C" __declspec(dllexport) double  math_pow(double mynumber1, double mynumber2)
{
  return pow(mynumber1,mynumber2);
}
The pow() function is just for test purposes - but useful anyway.
Now the script:

Code: [Select]

external "trigonometry.dll" cdecl double math_pow(double, double);
external "trigonometry.dll" cdecl double math_sin(double);
external "trigonometry.dll" cdecl double math_cos(double);
Game.Msg("sin(90) = " + math_sin(90));
Game.Msg("cos(90) = " + math_cos(90));
Game.Msg("pow(2,8) = " + math_pow(2,8));
The result:

pow(2,8) = 256.000000 (as expected!)

sin(90) = 0.893997 (what ?)
cos(90) = -0.448074 ( )

IMHO that's wrong! I'd expected them to be "0" and "1".
Changing the external lines to math_sin(int) or math_sin(float) didn't help, the values were wrong. I don't understand it !?

[Mnemonic]

That's because those C functions accept the angle in radians, not degrees ;-)

You need to change it to something like:

Code: [Select]

#define PI 3.1415926535f

extern "C" __declspec(dllexport) double  math_sin(double mynumber)
{
  return sin(mynumber * (PI / 180.0f));
}

...to convert "mynumber" to radians.

[Jerrot]

That's because those C functions accept the angle in radians, not degrees ;-)

Actually I don't feel like I could take over the world today... ! Thanks for the explanations, I guess a change is not necessary with that knowledge, I totally forgot about the radian mode on my calculator... or in school, damn!

@McCoy: If you haven't already done this by yourself, I'll post the source code and a link to a compiled version in the new plugins section. I guess all common trigonometric functions should be in there.

[McCoy]

thnx a lot man, i was planning to do it, but now i'm having my final exams so i dont have time. You saved me a lot of work!

Just one thing... can you ad a little function like RadToDeg() and DegToRad() ? I prefer using degrees instead of radians.

The math for this are here, just in case  :

Rad. to Deg-> Deg=rad*180/pi
Deg to Rad->  Rad=deg*pi/180

[Jerrot]

Just one thing... can you ad a little function like RadToDeg() and DegToRad() ? I prefer using degrees instead of radians.

You could do them in WME, eh ?
Anyway - I just added them, you can download v1.1 now...