How do I draw a rainbow in Freeglut?

Question

I\'m trying to draw a rainbow-coloured plot legend in openGL. Here is what I\'ve got so far:

glBegin(GL_QUADS);
for (int i = 0; i != legendElements; ++i)
{
          


        

Answer 1

Well, not completely right. Here I made a javascript example of it. Sodium yellow (589nm) is too orange and Halpha red (656nm) is too brown....

Save this example into an HTML file (jquery needed) and load it into a browser: page.html?l=[nanometers]