C++ idMat3::Identity方法代码示例

void idSimpleWindow::SetupTransforms( float x, float y )
{
	static idMat3 trans;
	static idVec3 org;
	
	trans.Identity();
	org.Set( origin.x + x, origin.y + y, 0 );
	if( rotate )
	{
		static idRotation rot;
		static idVec3 vec( 0, 0, 1 );
		rot.Set( org, vec, rotate );
		trans = rot.ToMat3();
	}
	
	static idMat3 smat;
	smat.Identity();
	if( shear.x() || shear.y() )
	{
		smat[0][1] = shear.x();
		smat[1][0] = shear.y();
		trans *= smat;
	}
	
	if( !trans.IsIdentity() )
	{
		dc->SetTransformInfo( org, trans );
	}
}

/*
 =======================================================================================================================
 =======================================================================================================================
 */
bool GetMatrixForKey(entity_t *ent, const char *key, idMat3 &mat)
{
    const char	*k;
    k = ValueForKey(ent, key);
    if (k && strlen(k) > 0)
    {
        sscanf
        (
            k,
            "%f %f %f %f %f %f %f %f %f ",
            &mat[0][0],
            &mat[0][1],
            &mat[0][2],
            &mat[1][0],
            &mat[1][1],
            &mat[1][2],
            &mat[2][0],
            &mat[2][1],
            &mat[2][2]
        );
        return true;
    }
    else
    {
        mat.Identity();
    }

    return false;
}

/*
================
idDict::GetMatrix
================
*/
bool idDict::GetMatrix( const char *key, const char *defaultString, idMat3 &out ) const {
	const char	*s;
	bool		found;
	if( !defaultString ) {
		defaultString = "1 0 0 0 1 0 0 0 1";
	}
	found = GetString( key, defaultString, &s );
	out.Identity();		// sccanf has a bug in it on Mac OS 9.  Sigh.
	sscanf( s, "%f %f %f %f %f %f %f %f %f", &out[0].x, &out[0].y, &out[0].z, &out[1].x, &out[1].y, &out[1].z, &out[2].x, &out[2].y, &out[2].z );
	return found;
}

/*
============
idTraceModel::GetMassProperties
============
*/
void idTraceModel::GetMassProperties( const float density, float &mass, idVec3 &centerOfMass, idMat3 &inertiaTensor ) const {
	volumeIntegrals_t integrals;

	// if polygon trace model
	if ( type == TRM_POLYGON ) {
		idTraceModel trm;

		VolumeFromPolygon( trm, 1.0f );
		trm.GetMassProperties( density, mass, centerOfMass, inertiaTensor );
		return;
	}

	VolumeIntegrals( integrals );

	// if no volume
	if ( integrals.T0 == 0.0f ) {
		mass = 1.0f;
		centerOfMass.Zero();
		inertiaTensor.Identity();
		return;
	}

	// mass of model
	mass = density * integrals.T0;
	// center of mass
	centerOfMass = integrals.T1 / integrals.T0;
	// compute inertia tensor
	inertiaTensor[0][0] = density * (integrals.T2[1] + integrals.T2[2]);
	inertiaTensor[1][1] = density * (integrals.T2[2] + integrals.T2[0]);
	inertiaTensor[2][2] = density * (integrals.T2[0] + integrals.T2[1]);
	inertiaTensor[0][1] = inertiaTensor[1][0] = - density * integrals.TP[0];
	inertiaTensor[1][2] = inertiaTensor[2][1] = - density * integrals.TP[1];
	inertiaTensor[2][0] = inertiaTensor[0][2] = - density * integrals.TP[2];
	// translate inertia tensor to center of mass
	inertiaTensor[0][0] -= mass * (centerOfMass[1]*centerOfMass[1] + centerOfMass[2]*centerOfMass[2]);
	inertiaTensor[1][1] -= mass * (centerOfMass[2]*centerOfMass[2] + centerOfMass[0]*centerOfMass[0]);
	inertiaTensor[2][2] -= mass * (centerOfMass[0]*centerOfMass[0] + centerOfMass[1]*centerOfMass[1]);
	inertiaTensor[0][1] = inertiaTensor[1][0] += mass * centerOfMass[0] * centerOfMass[1];
	inertiaTensor[1][2] = inertiaTensor[2][1] += mass * centerOfMass[1] * centerOfMass[2];
	inertiaTensor[2][0] = inertiaTensor[0][2] += mass * centerOfMass[2] * centerOfMass[0];
}

bool CFrobHandle::GetPhysicsToSoundTransform(idVec3 &origin, idMat3 &axis)
{
	idVec3 eyePos = gameLocal.GetLocalPlayer()->GetEyePosition();
	const idBounds& bounds = GetPhysics()->GetAbsBounds();

	//gameRenderWorld->DebugBounds(colorLtGrey, bounds, vec3_origin, 5000);
	
	// greebo: Choose the corner which is nearest to the player's eyeposition
	origin.x = (idMath::Fabs(bounds[0].x - eyePos.x) < idMath::Fabs(bounds[1].x - eyePos.x)) ? bounds[0].x : bounds[1].x;
	origin.y = (idMath::Fabs(bounds[0].y - eyePos.y) < idMath::Fabs(bounds[1].y - eyePos.y)) ? bounds[0].y : bounds[1].y;
	origin.z = (idMath::Fabs(bounds[0].z - eyePos.z) < idMath::Fabs(bounds[1].z - eyePos.z)) ? bounds[0].z : bounds[1].z;

	// The called expects the origin in local space
	origin -= GetPhysics()->GetOrigin();

	axis.Identity();

	//gameRenderWorld->DebugArrow(colorWhite, GetPhysics()->GetOrigin() + origin, eyePos, 0, 5000);

	return true;
}

/*
================
hhSound::GetPhysicsToSoundTransform
================
*/
bool hhSound::GetPhysicsToSoundTransform( idVec3 &origin, idMat3 &axis ) {
	origin = positionOffset;
	axis.Identity();
	return true;
}