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# Does this look right to you?

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I''m making a driving game and this is my torquelook up function i have an array of torque (don''t be fooled by its name, hp, ) values and an rpm, the torques are every 500 rpm so im interpolated between the 2 clossest torque values, how does this look?
double cCar::engtorque()
{
if (rpm == revlimit) return hp[revlimit];
else
{
return hp[rpm/500] + (hp[(rpm/500)+1] - hp[rpm/500]) * (rpm%500)/500;
}
}

It would probably run faster if i put rpm/500 in a variable but optimization is later.

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Bug:
	if (rpm == revlimit) return hp[ revlimit ];

should be
	if (rpm > revlimit) return hp[ NUM_TORQUES-1 ];

Optimization note: using 512 rather than 500 might make a difference.

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Sorry i didn't post the code right before it but in the function that calls this it says if (rpm > revlimit) rpm = revlimit; But, i realise that calling hp[revlimit] will over run the allocation by ALOT it needs to be hp[revlimit/500], or hp[rpm/500] since they are the same.

But i assume u mean everything else looks good, thanks.

edit:

void cCar::update(double deltat){	rpm = (long) /*wheel rotation rate **/ ((gear == -1) ? 0 : params->gearratios[gear])  * params->transratio * .7 * 60 / 2* pi; //60/2pi if in rads, 60/360 if in degrees	if (rpm < 1000) rpm = 1000;			//don't stall	if (rpm > params->revlimit) rpm = params->revlimit;	//dont' blow	double torque =  engtorque() * ((gear == -1) ? 0 : params->gearratios[gear]) * params->transratio * .7;			//guess on transeff (from .7-1)	double maxspeed = rpm * ((gear == -1) ? 0 : params->gearratios[gear]) * params->transratio * .7;					//rpm * gear * trans * efficiency	//######DRIVE################################################################	if (control & 1) //gas on	{		for (int i = ((params->fourwheel) ? 0 : 2); i < 4; i ++)		{			dJointSetHinge2Param(wheeljoints[i], dParamFMax2, torque); 			dJointSetHinge2Param(wheeljoints[i], dParamVel2, ((i % 2) == 0) ? -maxspeed : maxspeed); 		}	}	else if (control & 2) //brake on	{		for (int i = 0; i < 4; i ++)		{			dJointSetHinge2Param(wheeljoints[i], dParamFMax2, params->brakepower);			dJointSetHinge2Param(wheeljoints[i], dParamVel2, 0);		}	}	else //free wheel	{		for (int i = 0; i < 4; i ++)			dJointSetHinge2Param(wheeljoints[i], dParamFMax2, 0); //set it to have zero power	}}

[edited by - honayboyz on June 5, 2003 12:04:57 PM]

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