On to OpenGL and 3D Computer Graphics
Sumanta Guha · 2018
This chapter deals with OpenGL program to draw a square, the computer graphics equivalent of “Hello World”. It explains orthographic projection, the fixed world coordinate system OpenGL sets up and how the so-called viewing box in which the programmer draws is specified in this system. The chapter shows how parts of objects outside the viewing box are clipped off. It discusses OpenGL as a state machine and also explains about perspective projection as also hidden surface removal using the depth buffer. The chapter describes the reader to practice her newly-acquired skills, the topic of approximating curved objects. It provides to approximate a surface with triangles, rather than a curve with straight segments. Perhaps the best reason for OpenGL to be the Application Programming Interface of choice for students of three-dimensional computer graphics is and this is a consequence of its almost universal adoption by the academic, engineering and scientific communities the sheer volume of learning resources available.