rendering to multiple windows

[vietlf]

I want to create a solar sistem in full screen, and when the user selects a planet i want that in a small window to show only that planet spining and maybe some info text about it. How can i do that?

[mikael_aronsson]

glViewport allows you to select what area of a window to render to, so you can render your solar system first, then change the viewport to a smaller rectangle in one of the corners or something like that and render the "zoom in" there. (remember to reset the viewport at the end...)

Mikael

[vietlf]

ok....i tryed the glViewport but the problem is that is actualy rendering the whole scene in a part of the window.....and i just want to render a part....so it doesn't work

[mikael_aronsson]

Not sure I understand what the problem is, you can render anything you want to the current viewport, change the viewport and render something different any number of times if you want.

Mikael

[vietlf]

Yes, the thing is that i still want the solar sistem to be visible on the full screen(even if it doesn#t move anymore).
When i use glViewport the whole screeen becomes black besides the part where i render.....Can't i keep the big solar sistem, and render something differend the same time in a small window?

[Deiussum]

Did you also setup a scissor test for your new viewport? You can use that to keep glClear from clearing the rest of the scene.