   where am I ?
  Hello,i've got a question according to the coordinate systems used in opengl.When multiplying with the modelviewprojection matrix the object then is clip space.I have a camera class and compute the positions with vectors and then applythe new position with gluLookAt(..). Where is my camera then ? Still in object space or in world space ?regards,c-mos   
  I'd say world space. When doing mouse ray-picks you get the ray in world-space I think, and for that you just copy out the camera position for the view matrix, untouched.   ;  IIRC an opengl camera alway is at (0,0,0). With the look at matrix you create a matrix that trasforms the geometry in the camera local space. So, your camera (in world space) is at the 'eye' position, but actually everything is transformed to the camera local space...EDIT:Quote:I have a camera class and compute the positions with vectors and then applythe new position with gluLookAt(..). Sorry, I've missed that point...I would guess that the position of the camera doesn't change, and that the result is still (0,0,0) in camera space... don't quote me on that though...   ;  Hi,that would mean the camera's "raw" data is still on object space (the vectors).But multiplied with mvp-matrix it is in world space. how can I get thecamera position and view vector from the modelview matrix ?with glGetDouble(matrix, GL_MODELVIEW_MATRIX) I get the current model viewmatrix. But this matrix holds a lot of information. scale, transoformations etc.regards,c-mos   