Introduction - If you have any usage issues, please Google them yourself
OpenGL demo. 1 to create a window, the window is divided into four. The first one to draw a line (dashed, solid, thick line), the second block of drawing polygons, the third block window polygon with a gradient fill, the fourth round draw block window. 2 Right-click each one, then a separate display the contents of the block. Solo show, you can use the left mouse button to drag on the display, zoom with scroll wheel. Right-click again, the content is displayed 4.