maybe anyone knows of a good tutorial or sample of implementing free movement in 3d (with quaternions). not the source, but the particular algorithm is what bothers me. (use D3DX for gods sake

well.. if you want completely free movement just generate for example from the mousemovement eulerangles, generate a quat from this and multiply it by the current quat. to draw the scene, rotate it by that current quat.

"take a look around" - limp bizkit
www.google.com

Well I do generate a quat from euler angles and then make a matrix from it - it stills show the gimbal lock effect ((

logically you get the same problems if you just use your eulerangles directly, wich is what you do.

euler->quat->matrix->transform is essencially the same as
euler->transform
just some conversions before..
what you have to do is STORING the current orientation

quat myorientation;

then in the update func you have something like this:

update() {
quat rotation = get_rotation_change_from_eulers();
//THIS LINE!!!!
myorientation *= rotation;
}

and where you set up your camera you do this:

setupcamera() {
matrix rotation = myorientation.getmatrix();
loadmatrix(rotation);
}

you have to STORE your current rotation, and apply the change on it. THEN quaternions solve your gimbal lock, not if you use eulers the way you did before..

"take a look around" - limp bizkit
www.google.com

Well i do create the orientation quaternion, get matrix from it and multiply it with translation matrix, then update the position, but somehow after a coulpe of turns my object starts flying backwards .... and in other directions :/

here''s the code:
****************

// Ship position & orientation
static D3DXVECTOR3 vPosition(0.0f, -15.0f, -30.0f);
static D3DXQUATERNION qOrientation(0.0f, 0.0f, -1.0f, 0.0f);

// Direction quats
D3DXQUATERNION qRight;
D3DXQUATERNION qLeft;
D3DXQUATERNION qUp;
D3DXQUATERNION qDown;
D3DXQUATERNION qQ1;
D3DXQUATERNION qQ2;
D3DXQuaternionRotationAxis(&qRight, &D3DXVECTOR3(0, 1, 0), 0.02f);
D3DXQuaternionRotationAxis(&qLeft, &D3DXVECTOR3(0, 1, 0), -0.02f);
D3DXQuaternionRotationAxis(&qUp, &D3DXVECTOR3(1, 0, 0), 0.02f);
D3DXQuaternionRotationAxis(&qDown, &D3DXVECTOR3(1, 0, 0), -0.02f);
D3DXQuaternionRotationAxis(&qQ1, &D3DXVECTOR3(0, 0, 1), 0.02f);
D3DXQuaternionRotationAxis(&qQ2, &D3DXVECTOR3(0, 0, 1), -0.02f);

// Input
Input.UpdateKeyboard();
if (Input.KeyPressed(DIK_D)) qOrientation = qRight* qOrientation;
if (Input.KeyPressed(DIK_A)) qOrientation = qLeft* qOrientation;
if (Input.KeyPressed(DIK_W)) qOrientation = qUp* qOrientation;
if (Input.KeyPressed(DIK_S)) qOrientation = qDown* qOrientation;
if (Input.KeyPressed(DIK_Q)) qOrientation = qQ1 * qOrientation;
if (Input.KeyPressed(DIK_E)) qOrientation = qQ2 * qOrientation;
D3DXQuaternionNormalize(&qOrientation, &qOrientation);

// Generate matrices
D3DXMATRIX mFinal;
D3DXMatrixRotationQuaternion(&mFinal, &qOrientation);

// Update position
vPosition.x += mFinal._13 / 50;
vPosition.y += mFinal._23 / 50;
vPosition.z += mFinal._33 / 50;

mFinal._41 = vPosition.x;
mFinal._42 = vPosition.y;
mFinal._43 = vPosition.z;

my fault, forgot that matrrices have lines, not columns in dx

vPosition.x += mFinal._31 / 50;
vPosition.y += mFinal._32 / 50;
vPosition.z += mFinal._33 / 50;

is the right way

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Keep it simple, stupid