Because college courses in higher mathematics studied linear algebra-related content

Because college courses in higher mathematics studied linear algebra-related content, so the time to learn 3D programming is the fact that a jump later, when some elements of learning to feel very depressed, (4,5 years of no use , and inevitably forget) often rely on high-level API to complete the final, but the fact that these specific algorithms to achieve high-level API Han's basic read, so decided to come back some good to understand the basis, of course, the first part of mathematics. In order to better achieve the visual effect, as well as in a complex matrix operations when validation result of the operation, will be introduced freemat or scilab (5.1.1) or GNU Octave (3.2.3) the use of this software as the matlab three alternatives to use. Can not be a huge matlab is kind of a relief, default freemat, architectural visualization not enough time to consider other alternatives. Specific calculations involved as far as possible to achieve both versions of DirectX and Irrlicht will refer to some source code. (See the formula used in C / C implementation) Basically, I hope to explain the main concepts, best intuitive explanation.
Vector
Size can be expressed using only the amount called the number, such as temperature, quality and so on. Both need to use the size of that, but also the amount of direction is called the vector, such as displacement, velocity and so on. Geometry, we use the directed line segment to represent the vector. There are two variables to determine a vector, that vector length and vector direction. Volume and position-independent, have the same length and direction of the two vectors are equal. There are specialized in irrlicht class vector2d, vector3d were to represent two-dimensional, 3d rendering 3-dimensional vector. In DirectX is the structure used to represent vector D3DXVECTOR2, D3DXVECTOR3, D3DXVECTOR4.
Right-hand coordinate system
A picture is worth a foreword, do not know how to hand gestures look at the distorted figure, is left to understand Han, Han is a right-handed coordinate system. OpenGL is used in the right-handed coordinate system, DirectX, Irrlicht is used in the left-handed coordinate system