lyallmarcus

So I've got two qt's or tiffs with alpha channels. And I want to use the alpha channels as clipping maps for videoplanes.

So I have transparent areas of one video plane that show the the other videoplane or background playing behind it.

I know I have to use the blend_mode attribute but I'm obviously missing something.

The patch is setup to accept two tiffs or qts with alpha channels.

idiot-gl-blending-question

Your patch works for me with depth_enable 0. Note that we don't want 

to clip based on depth testing (as demonstrated in the 

jit.gl.videoplane-xfade.pat example). Using depth testing (which is 

on by default) will only render one video plane in your patch since 

the video planes are both at the same distance from the camera.

The other thing worth noting is that right to left order is not 

maintained necessarily with send recieve, so the other possibility 

is that your left movie (which looks like the one you are assuming to 

have alpha) renders first, and that the right movie renders second 

(with no alpha, overlaying over the image). You will want to use 

either two instances of send/receive (as demonstrated in 

jit.gl.videoplane-example.pat) or use one receive with trigger to 

Lastly, you'll want to turn automatic off as demonstrated in as 

demonstrated in jit.gl.videoplane-example.pat.

Your patch works for me with depth_enable 0. Note that we don't want  
to clip based on depth testing (as demonstrated in the  
jit.gl.videoplane-xfade.pat example). Using depth testing (which is  
on by default) will only render one video plane in your patch since  
the video planes are both at the same distance from the camera.

The other thing worth noting is that right to left order is not  
maintained necessarily  with send recieve, so the other possibility  
is that your left movie (which looks like the one you are assuming to  
have alpha) renders first, and that the right movie renders second  
(with no alpha, overlaying over the image). You will want to use  
either two instances of send/receive (as demonstrated in  
jit.gl.videoplane-example.pat) or use one receive with trigger to  
force sequencing.

Lastly, you'll want to turn automatic off as demonstrated in as  
demonstrated in jit.gl.videoplane-example.pat.

idiot gl blending question