Rotation in 3D

Nathan Boyes · 2013-06-15T20:30:57

I am using direct x to try and make a free roaming camera. I am having a bit of difficulty when it comes to rotation. I have tried a few things, each having different result, none being the results that I want. This is basically how my camera system works. I plan on changing it a lot later, but i needed this to be done fast, and its mostly functional. for(auto index = targets.begin(); index != targets.end(); index++) { auto node = static_cast<CameraNode*>(*index); if(node->Player != NULL) { Position = node->Position;//this is a pointer to the players position vector } if(Position != NULL) { static int i; i++; //Deal with the matrices D3DXMATRIX mTranslate; D3DXMATRIX mRotateX; D3DXMATRIX mRotatey; D3DXMATRIX mRotatez; D3DXMATRIX mScale; //MAYBEH LAAAAATA D3DXMATRIX mWorld; //Set All Matrices to a neutral state D3DXMatrixIdentity(& mWorld); D3DXMatrixIdentity(&mTranslate); D3DXMatrixIdentity(& mRotateX); D3DXMatrixIdentity(& mRotatey); D3DXMatrixIdentity(& mRotatez); D3DXMatrixIdentity(& mScale); //MoveEverythaaaang D3DXMatrixTranslation(&mTranslate,Position->Position.x,Position->Position.y,Position->Position.z); D3DXMatrixRotationX(&mRotateX,Position->Angle.x*(M_PI/180)); D3DXMatrixRotationY(&mRotatey,Position->Angle.y*(M_PI/180)); D3DXMatrixRotationZ(&mRotatez,Position->Angle.z*(M_PI/180)); //Update the world mWorld = mTranslate * mRotateX * mRotatey * mRotatez;// this line maximum important // set the view transform D3DXMatrixLookAtLH(&node->Camera->mCamera, &D3DXVECTOR3 (0.0f, 0.0f, 600.0f), // the camera position &D3DXVECTOR3 (0.0f, 0.0f, 0.0f), // the look-at position &D3DXVECTOR3 (0.0f, -1.0f, 0.0f)); // the up direction // set the projection transform D3DXMatrixPerspectiveFovLH(&node->Camera->mLense, D3DXToRadian(45), (FLOAT)600 / (FLOAT)600, 1.0f, // the near view-plane 1000000.0f); // the far view-plane node->Camera->mCamera = node->Camera->mCamera * mWorld; } } So basically I am multiplying the camera's matrix by a matrix that is being affected by a vector containing pitch, yaw, and whatever the name for the other axis of rotation is, and a position vector Now if I multiply mtranslate by the rotation matrices, then I can turn my camera just fine, but moving forward only goes the base forward, so it I am looking left, forward is not to the left, but remains unchanged. if i do it the other way around then when i rotate I orbit around the center point. To counter this I when't with the one that would still move forward and backwards independent of which direction you are looking and threw this in to my player move thing. for(auto index = targets.begin(); index != targets.end(); index++) { auto node = static_cast<MoveNode*>(*index); //Deal with the matrices D3DXMATRIX mTranslate; D3DXMATRIX mRotateX; D3DXMATRIX mRotatey; D3DXMATRIX mRotatez; D3DXMATRIX mScale; //MAYBEH LAAAAATA D3DXMATRIX mWorld; //Set All Matrices to a neutral state D3DXMatrixIdentity(& mWorld); D3DXMatrixIdentity(&mTranslate); D3DXMatrixIdentity(& mRotateX); D3DXMatrixIdentity(& mRotatey); D3DXMatrixIdentity(& mRotatez); D3DXMatrixIdentity(& mScale); //MoveEverythaaaang D3DXMatrixTranslation(&mTranslate,node->Position->Position.x,node->Position->Position.y,node->Position->Position.z); D3DXMatrixRotationX(&mRotateX,node->Position->Angle.x*-(M_PI/180)); D3DXMatrixRotationY(&mRotatey,node->Position->Angle.y*-(M_PI/180)); D3DXMatrixRotationZ(&mRotatez,node->Position->Angle.z*-(M_PI/180)); D3DXMATRIX mRotation = mRotateX * mRotatey * mRotatez; D3DXVECTOR3 Position; //D3DXVec3TransformCoord(&Position,&node->Velocity->VelocityPos,&mRotateX);w D3DXVec3TransformCoord(&Position,&node->Velocity->VelocityPos,&mRotation); //D3DXVec3TransformCoord(&Position,&node->Velocity->VelocityPos,&mRotatez); node->Position->Position += Position;// * time; node->Position->Position += Position;// * time; node->Position->Angle += node->Velocity->AngularVelocity;// * time; } Now this works if I only rotate on one axis, but as soon as I start rotating on 2 things go crazy! Any advise on how I should go about making this not go insane for a free roaming camera/how have you accomplished what I am trying to do in the past?