[Plib-users] Matrices and sgCoord

[Dimitris M. <dm...@ya...>]

The following code has been a success in order to make the object move at a=
 constant speed.=0A=0AsgCoord stigma;=0A=0Avoid GLObject::setStigma( sgMat4=
 & objDst){=0A    sgSetCoord( & stigma, objDst);=0A}=0A=0AGLObject::move(){=
=0A    //The rotation matrix for moving around trireme.=0A    sgMat4 Rotate=
Matrix =3D   {=0A        1, 0, 0, 0,=0A        0, 1, 0, 0,=0A        0, 0, =
1, 0,=0A        0,( getSpeed()), 0, 1=0A    };=0A    =0AsgMakeCoordMat4( SH=
IPSRC, &trireme->getStigma());=0AsgMultMat4( SHIPDST, SHIPSRC, RotateMatrix=
);=0AsetStigma( SHIPDST);=0A=0AWhat I don;t understand is that I took the u=
sual matrix and instead tweaking the last column element by the second row,=
=0AI inversed it and put the getSpeed() which is <>0 in the bottom row! Why=
? this?=0AI made then the matrix multiplications, and took the result to sg=
Coord.=0AIs this right approach? Ok it works, but it worths?=0A=0A=0A=0A=0A=
=0A       =0A______________________________________________________________=
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