As a 3D game programmer, sooner or later the time comes when you get bored with spinning cubes and flying space ships in space. You want fully articulated 3D characters and anima­tion. So you start looking on Internet for information… читать далее

You can use quaternions to rotate vectors or other quaternions. The same formula is used to rotate quaternions by other quaternions as to rotate vectors by other quaternions. The only difference is that the vector becomes a quaternion with a… читать далее

When your joints are animating smoothly, it is time to attach the mesh. The mesh is what makes up the shape of the model. It is a group of vertices and triangles that help the model have volume and detail.… читать далее

Okay, on to matrix multiplication! Lots of people get confused when it comes to multiplying matrices. In reality, however, it really isn’t that hard. The first thing you need to do is determine whether the matrices are conformable. Lets say… читать далее

Before you begin, you might want to pull up the source code for this chapter. The files pertaining to the MD2 models are named md2.h and md2.cpp. Both of these files can be found in the Code/Chapter_3 direc­tory on the… читать далее

W ell, you made it. By now you should have a greater understanding of one of the most important parts in a 3D game, the 3D model. Using the information in this book, you can now load, display, and animate… читать далее

The dot product can be used to find the angle between two vectors and is a quick test to determine whether two vectors are orthogonal (at right angles to each other). This can be useful in 3D programming if you… читать далее

Because the OBJ format can be unpredictable and also because it can be edited easily, it is helpful to have some error checking in place. For instance, the face structures may reference invalid vertices, such as vertex number -2, or… читать далее

A new trend is creeping into video games at an incredible rate. This trend makes games more realistic, more believable, and in some cases, more fun. A large percentage of new games use this trend, and consumers are gobbling these… читать далее

Because of the complicated nature of quaternions, it is not always feasible to specify a quaternion rotation directly. Instead, you might want to specify a set of three Euler angles, or perhaps a rotation around an arbitrary axis, particularly if… читать далее