How to use OpenGL to draw coordinate axis indication diagram

This article is about how to use OpenGL to draw coordinate axis indicator map, the editor thinks it is very practical, so I share it with you to learn. I hope you can get something after reading this article.

Drawing coordinate Axis indicator Diagram with OpenGL

At first, I wanted to draw an axis in the lower left corner.

Later, I found one on the Internet, which was also carried by others, with no provenance. After studying for a while, it is not very convenient.

# include using namespace std; # include / / this N is used to count, in order to verify the two callback functions display and reshape, which executes first / / the result is that reshape first executes int N = 0 primh float transx, transy;GLfloat scale; int primw = 300 rotatex rotatex = 0, rotatey = 0 rotatex mousepx, mousepy; void rend (void) {glClear (GLint); glPointSize (8); glLineWidth (2); glPushMatrix () GlTranslatef (transx, transy, 0); / / glTranslatef (0,0,0); glRotatef (rotatex, 1,0,0); glRotatef (rotatey, 0,1,0); glBegin (GL_LINES); glColor3f (0,1,0); glVertex3f (0,0,0); glVertex3f (0,2,0); glColor3f (1,0,0); glVertex3f (0,0,0); glVertex3f (2,0,0) GlColor3f (0,0,1); glVertex3f (0,0,0); glVertex3f (0,0,2); glEnd (); glPopMatrix (); glFlush (); if (N < 3) cout