Elementclasses.cpp:
elements.push_back(Element_METH());
Meth.cpp
#include "simulation/Elements.h"
//#TPT-Directive ElementClass Element_METH PT_METH 167
Element_METH::Element_METH()
{
    Identifier = "DEFAULT_PT_METH";
    Name = "METH";
    Colour = PIXPACK(0xBFB8BB);
    MenuVisible = 1;
    MenuSection = SC_GAS;
    Enabled = 1;

    Advection = 0.6f;
    AirDrag = 0.01f * CFDS;
    AirLoss = 0.98f;
    Loss = 0.60f;
    Collision = -0.1f;
    Gravity = 0.0f;
    Diffusion = 1.00f;
    HotAir = 0.000f	* CFDS;
    Falldown = 0;

    Flammable = 50;
    Explosive = 0;
    Meltable = 0;
    Hardness = 0;

    Weight = 1;

    Temperature = R_TEMP+0.0f	+273.15f;
    HeatConduct = 30;
    Description = "Methane, flammable gas";

    State = ST_GAS;
    Properties = TYPE_GAS;

    LowPressure = IPL;
    LowPressureTransition = NT;
    HighPressure = IPH;
    HighPressureTransition = NT;
    LowTemperature = ITL;
    LowTemperatureTransition = NT;
    HighTemperature = 600.00;
    HighTemperatureTransition = PT_FIRE;
}
Elementclasses.h
#define PT_METH 167

class Element_METH: public Element
{
public:
	Element_METH();
	virtual ~Element_METH();
};