Drawing Triangles That are outlined and filled

OpenGL OpenGL: Basic Coding
1

Does anyone know of way to draw triangles in GL so that it is outlined in one color and filled in another?

2

There must be a better way to do it, but here’s one:

first draw your triangle using glPolygonMode(GL_FRONT_AND_BACK,GL_FILL) and use your desired color.
then draw the triangle again using glPolygonMode(GL_FRONT_AND_BACK,GL_LINES) using your outline color.

3

That’s the correct OpenGL way to do it.
The line mode is GL_LINE! GL_LINES is used elsewhere.
Lookup glPolygonOffset to find how you can avoid depth buffering artifacts of the lines in this case.