template<int rows, typename T>
class Ogre::TransformBase< rows, T >
Class encapsulating a standard 4x4 homogeneous matrix.
OGRE uses column vectors when applying matrix multiplications, This means a vector is represented as a single column, 4-row matrix. This has the effect that the transformations implemented by the matrices happens right-to-left e.g. if vector V is to be transformed by M1 then M2 then M3, the calculation would be M3 * M2 * M1 * V. The order that matrices are concatenated is vital since matrix multiplication is not commutative, i.e. you can get a different result if you concatenate in the wrong order.
- The use of column vectors and right-to-left ordering is the standard in most mathematical texts, and is the same as used in OpenGL. It is, however, the opposite of Direct3D, which has inexplicably chosen to differ from the accepted standard and uses row vectors and left-to-right matrix multiplication.
- OGRE deals with the differences between D3D and OpenGL etc. internally when operating through different render systems. OGRE users only need to conform to standard maths conventions, i.e. right-to-left matrix multiplication, (OGRE transposes matrices it passes to D3D to compensate).
- The generic form M * V which shows the layout of the matrix entries is shown below:
[ m[0][0] m[0][1] m[0][2] m[0][3] ] {x}
| m[1][0] m[1][1] m[1][2] m[1][3] | * {y}
| m[2][0] m[2][1] m[2][2] m[2][3] | {z}
[ m[3][0] m[3][1] m[3][2] m[3][3] ] {1}