Jump to content
  • Advertisement
Sign in to follow this  

[DirectX9.0]How to retrive vector from Camera setting's View Matrix

This topic is 3499 days old which is more than the 365 day threshold we allow for new replies. Please post a new topic.

If you intended to correct an error in the post then please contact us.

Recommended Posts

I have set view matrix like this: D3DXVECTOR3 vEyePt( 0.0f, 2.0f, -3.0f ); D3DXVECTOR3 vLookatPt( 0.0f, 0.9f, 0.0f ); D3DXVECTOR3 vUpVec( 0.0f, 1.0f, 0.0f ); D3DXMATRIXA16 matView; D3DXMatrixLookAtLH( &matView, &vEyePt, &vLookatPt, &vUpVec ); g_pd3dDevice->SetTransform( D3DTS_VIEW, &matView ); I want to retrive the eye, lookat and up vector for a purpose to change the vector.I get the eye point like this way: D3DXMATRIXA16 m; g_pd3dDevice->GetTransform(D3DTS_VIEW, &m); D3DXMATRIX invm; D3DXMatrixInverse(&invm,NULL,&m); D3DXVECTOR3 v; D3DXVECTOR3 cameraLoc; v.x = 0; v.y = 0; v.z = 0; D3DXVec3TransformCoord(&cameraLoc,&v,&invm); Does anybody knows how the get the other lookat and up vector? Thanks in advance.... Kallol

Share this post

Link to post
Share on other sites

A lookAt-Vector can be retrieved but not a lookAt-Point, obviously. If you need the lookAt-Point instead of the vector, you need to store the creation values everytime the camera gets updated, which is probably a good idea anyway.

Kinda like:

void CameraClass::updateCamera(const MYVEC3& eye, const MYVEC3& lookAt, const MYVEC3& up)
this.eye = eye;
this.lookAt = lookAt;
this.up = up;

D3DXMatrixLookAtLH( &this.CameraMatrix, &eye, &lookAt, &up );

Of course that method should be the only publically available way to change the camera transform.

That makes retrieving the values easy, no need to do some matrix/vector calculations at all.


Share this post

Link to post
Share on other sites
Sign in to follow this  

  • Advertisement

Important Information

By using GameDev.net, you agree to our community Guidelines, Terms of Use, and Privacy Policy.

We are the game development community.

Whether you are an indie, hobbyist, AAA developer, or just trying to learn, GameDev.net is the place for you to learn, share, and connect with the games industry. Learn more About Us or sign up!

Sign me up!