about the function glLooAt(x,x,x, x,x,x, upx,upy,upz);
if i use it to set my camera,and up vecotr is (0,-1,0),so
what are the pitch,yaw,roll components???
LookAt does not use pitch,yaw,roll. Once you have created the view matrix you can extra the pitch,yaw,roll. These are the euler angles
You might read this
https://truesculpt.googlecode.com/hg-history/38000e9dfece971460473d5788c235fbbe82f31b/Doc/rotation_matrix_to_euler.pdf