need help with making the background transparent

OpenGL Development JOGL Development
#1

i just started experimenting a litle with jogl and even though i dont know anything about opengl it seems interesting(so this is probably REALLY stupid question)
im trying to mess around a little with the ready jogl examples and especially seeing how they work with other APIs like JMF . so heres my problem:

i am trying to put the Gears example in a frame that already contains and playing a video file.although it was pretty easy to make them appear on the same frame(gears on top of the video) i cant make the black background of the gears go away.i searched everywhere, reading about rgba and stuff and i tried a lot of things to make it work but nothing.the best thing i did so far is making this background white :o

i use a GLcanvas that i add it on the video frame(maybe thats the problem?)

can someone plz explain me how this work and how can i get only the gears appearing on the video?

#2

You can’t do this with the heavyweight GLCanvas. The Swing-compatible GLJPanel allows mixing of Java2D and OpenGL rendering results; see the JGears demo. With Java SE 6 and -Dsun.java2d.opengl=true the GLJPanel is basically just as fast as the GLCanvas, but is relatively slow on earlier JDKs. I’m not sure how JMF is getting its video results on to the screen. If you are able to get a hold of the decompressed pixels you could probably use EXT_pixel_buffer_object in combination with a textured quad to draw the video using OpenGL which would work around this issue.

#3

i tried to make it with the JGears instead of Gears but gets even more complicated. the thing is that i cant understand what defines the background in jogl. i mean is there a command that defines it(and if so why there is no command to make it transparent)?and why when i call for example the Gears(or JGears) to put it on a canvas or GLJPanel or whatever i always call the background color too?i saw Jgears and frankly couldnt understand whats different since the checkbox was either not working or coudnt understand what it changed(the background was still black no matter what)

the other way u recommended its a really nice way but i dont think i can do it since im really beginner in jogl so ill stick to trying to find a way more java-oriented and not gl-oriented since i cant really program yet more than messing around with the ready examples

thx for the advices anyway

#4

really guys what the JGears checkbutton suppose to do?cant really see anything happen no matter what

#5

If I remeber well, with transparency on you’ll have a nice grey background (which is the color of the background of your JPanel) without you’ll see a black background which is the color of the glClearColor…