vodstrup

Hopefully someone can help me out with this - or give me a hint of

I am trying to blue screen (chromakey) a video and place it on a

videoplane - and then "position" the videoplane over another. I can

do this easily with luminance/alpha but can't figure out how to do it

with chroma - two examples are posted below.

Also, out of curiosity, why is there a "position" argument for a slab?

Is there a way to write a shader to take advantage of position? Just

sending a position message "pak position 0. 0. 0." didn't have any

Hopefully someone can help me out with this - or give me a hint  of
how best to do it...

I am trying to blue screen (chromakey) a video and place  it on a
videoplane - and then "position" the videoplane over another.  I can
do this easily with luminance/alpha but can't figure out how to do it
with chroma - two examples are posted below.

Also, out of curiosity, why is there a "position" argument for a slab?
 Is there a way to write a shader to take advantage of position?  Just
sending a position message "pak position 0. 0. 0." didn't have any
effect.

move-a-videoplane-with-chromakey-and-why-position-argument-on-a-slab

Depending on how much flexibility of movement you want, there are 2 basic ways:

1) Do some image space manipulation using texture coordinate offsets

for the foregound video. For this, you would add an offset parameter

to the chromakey shader and send a message to the slab to move the

2) Output using mode 1 of the chromakey shader to get just the alpha

channel and use that as a mask for the video by sending both the

original texture and the chromakey generated alpha channel to a

videoplane. If @blend_enable 1 and @depth_enable 0 you can then layer

this on top of the other texture which is also on a videoplane and

> Hopefully someone can help me out with this - or give me a hint of

> I am trying to blue screen (chromakey) a video and place it on a

> videoplane - and then "position" the videoplane over another. I can

> do this easily with luminance/alpha but can't figure out how to do it

> with chroma - two examples are posted below.

> Also, out of curiosity, why is there a "position" argument for a slab?

> Is there a way to write a shader to take advantage of position? Just

> sending a position message "pak position 0. 0. 0." didn't have any

> #P newex 632 269 105 196617 jit.qt.movie 320 240;

> #P newex 87 282 76 196617 unpack 0. 0. 0.;

> #P window setfont "Fixedwidth Serif" 10.;

> #P newex 87 261 92 1441802 vexpr $i1/255.;

> #P newex 87 141 105 196617 jit.qt.movie 320 240;

> #P user jit.pwindow 86 196 82 62 0 0 0 0 1 0;

> #P flonum 447 282 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;

> #P message 447 305 85 196617 param binary $1;

> #P flonum 366 282 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;

> #P message 366 305 79 196617 param mode $1;

> #P flonum 289 282 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;

> #P message 289 305 75 196617 param fade $1;

> #P flonum 219 282 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;

> #P message 219 305 68 196617 param tol $1;

> #P newex 87 305 130 196617 pak param color 0. 0. 1. 0.;

> #P newex 70 419 206 196617 jit.gl.videoplane valente @scale 1.333 1. 1.;

> #P newex 112 104 238 196617 jit.gl.render valente @erase_color 0.5 0.5 0.5 1.;

> #P newex 70 371 198 196617 jit.gl.slab valente @file co.chromakey.jxs;

1) Do some image space manipulation using texture coordinate offsets
for the foregound  video.  For this, you would add an offset parameter
to the chromakey shader and send a message to the slab to move the
image around.

2) Output using mode 1 of the chromakey shader to get just the alpha
channel and use that as a mask for the video by sending both the
original texture and the chromakey generated alpha channel to a
videoplane.  If @blend_enable 1 and @depth_enable 0 you can then layer
this on top of the other texture which is also on a videoplane and
move it around in 3D.

On 8/11/07, bart woodstrup  wrote:
> Hi,
>
> Hopefully someone can help me out with this - or give me a hint  of
> how best to do it...
>
> I am trying to blue screen (chromakey) a video and place  it on a
> videoplane - and then "position" the videoplane over another.  I can
> do this easily with luminance/alpha but can't figure out how to do it
> with chroma - two examples are posted below.
>
> Also, out of curiosity, why is there a "position" argument for a slab?
>  Is there a way to write a shader to take advantage of position?  Just
> sending a position message "pak position 0. 0. 0." didn't have any
> effect.
>
> How I'd like to do it:
>
> #P window setfont "Sans Serif" 9.;
> #P window linecount 1;
> #P message 53 118 30 196617 read;
> #P toggle 61 33 15 0;
> #P newex 61 55 51 196617 qmetro 2;
> #P message 447 257 17 196617 1.;
> #P message 219 246 31 196617 0.18;
> #P newex 219 217 48 196617 loadbang;
> #P message 632 246 30 196617 read;
> #P newex 632 269 105 196617 jit.qt.movie 320 240;
> #P newex 62 78 61 196617 t b b erase;
> #P newex 87 168 56 196617 qlim 2500;
> #P newex 87 282 76 196617 unpack 0. 0. 0.;
> #P window setfont "Fixedwidth Serif" 10.;
> #P newex 87 261 92 1441802 vexpr $i1/255.;
> #P window setfont "Sans Serif" 9.;
> #P newex 87 141 105 196617 jit.qt.movie 320 240;
> #P user suckah 87 197 80 61;
> #P user jit.pwindow 86 196 82 62 0 0 0 0 1 0;
> #P flonum 447 282 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
> #P message 447 305 85 196617 param binary $1;
> #P flonum 366 282 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
> #P message 366 305 79 196617 param mode $1;
> #P flonum 289 282 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
> #P message 289 305 75 196617 param fade $1;
> #P flonum 219 282 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
> #P message 219 305 68 196617 param tol $1;
> #P newex 87 305 130 196617 pak param color 0. 0. 1. 0.;
> #P newex 70 419 206 196617 jit.gl.videoplane valente @scale 1.333 1. 1.;
> #P newex 112 104 238 196617 jit.gl.render valente @erase_color 0.5 0.5 0.5 1.;
> #P newex 70 371 198 196617 jit.gl.slab valente @file co.chromakey.jxs;
> #P toggle 372 435 15 0;
> #P message 372 453 70 196617 fullscreen $1;
> #P newex 357 472 141 196617 jit.window valente @interp 1;
> #P window linecount 3;
> #P comment 278 366 100 196617 I'd like to move the foreground video
> over the background;
> #P fasten 23 0 4 1 637 353 263 353;
> #P connect 22 1 18 0;
> #P connect 22 1 23 0;
> #P connect 24 0 23 0;
> #P connect 15 0 14 0;
> #P connect 27 0 15 0;
> #P connect 25 0 26 0;
> #P fasten 25 0 27 0 224 241 452 241;
> #P connect 3 0 2 0;
> #P connect 13 0 12 0;
> #P fasten 2 0 1 0 377 470 362 470;
> #P connect 11 0 10 0;
> #P connect 26 0 9 0;
> #P fasten 26 0 11 0 224 274 294 274;
> #P fasten 14 0 4 1 452 332 263 332;
> #P fasten 12 0 4 1 371 332 263 332;
> #P fasten 10 0 4 1 294 332 263 332;
> #P fasten 8 0 4 1 224 332 263 332;
> #P fasten 7 0 4 1 92 332 263 332;
> #P connect 9 0 8 0;
> #P fasten 20 2 7 4 158 302 188 302;
> #P fasten 20 1 7 3 125 302 164 302;
> #P fasten 20 0 7 2 92 302 140 302;
> #P fasten 22 0 5 0 67 99 117 99;
> #P connect 22 2 5 0;
> #P connect 19 0 20 0;
> #P connect 17 0 19 0;
> #P connect 21 0 16 0;
> #P fasten 18 0 4 0 92 163 75 163;
> #P connect 18 0 21 0;
> #P connect 30 0 18 0;
> #P connect 4 0 6 0;
> #P connect 28 0 22 0;
> #P connect 29 0 28 0;
> #P window clipboard copycount 31;
>
>
>
> This was a lame attempt:
>
>
>
>
> #P window setfont "Sans Serif" 9.;
> #P flonum 388 582 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
> #P flonum 351 582 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
> #P flonum 314 582 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
> #P window linecount 1;
> #P newex 285 603 99 196617 pak position 0. 0. 0.;
> #P message 470 438 21 196617 0.1;
> #P message 425 438 21 196617 0.2;
> #P newex 425 415 44 196617 loadbang;
> #P newex 303 438 93 196617 unpack 0. 0. 0.;
> #P newex 303 415 77 196617 vexpr $i1/255.;
> #P message 178 478 41 196617 mode 2;
> #P message 135 478 40 196617 mode 1;
> #P message 90 478 40 196617 mode 0;
> #P flonum 470 457 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
> #P message 470 478 42 196617 fade $1;
> #P flonum 425 458 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
> #P message 425 478 35 196617 tol $1;
> #P flonum 385 458 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
> #P flonum 344 458 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
> #P flonum 303 458 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
> #P flonum 262 458 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
> #P newex 221 478 177 196617 pak color 0. 0. 0. 0.;
> #P newex 68 508 116 196617 jit.chromakey @mode 1;
> #B color 5;
> #P newex 303 329 56 196617 qlim 2500;
> #P user suckah 303 350 80 61;
> #P user jit.pwindow 302 349 82 62 0 0 0 0 1 0;
> #P user jit.fpsgui 28 184 60 196617 0;
> #P newex 664 495 160 196617 jit.gl.texture blend @name mov2;
> #P newex 720 541 47 196617 r draw2;
> #P newex 664 567 249 196617 jit.gl.videoplane blend @blend_enable 1
> @automatic 0;
> #P newex 29 581 76 196617 append blender;
> #P newex 29 558 157 196617 jit.gl.texture blend @name mov1;
> #P newex 68 529 264 196617 jit.gl.texture blend @colormode lumalpha
> @name blender;
> #P newex 85 604 47 196617 r draw1;
> #N vpatcher 20 74 179 252;
> #P window setfont "Sans Serif" 9.;
> #P window linecount 0;
> #P newex 48 85 30 196617 t b b;
> #P window linecount 1;
> #P newex 68 107 47 196617 s draw2;
> #P newex 48 129 47 196617 s draw1;
> #P newex 24 54 58 196617 t b b erase;
> #P inlet 24 34 15 0;
> #P outlet 24 85 15 0;
> #P connect 1 0 2 0;
> #P connect 2 0 0 0;
> #P fasten 2 2 0 0 77 78 29 78;
> #P connect 2 1 5 0;
> #P connect 5 0 3 0;
> #P connect 5 1 4 0;
> #P pop;
> #P newobj 29 140 41 196617 p draw;
> #P newex 29 630 249 196617 jit.gl.videoplane blend @blend_enable 1 @automatic 0;
> #P flonum 860 424 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
> #P message 860 445 42 196617 rate $1;
> #P message 751 424 30 196617 read;
> #P message 797 446 27 196617 stop;
> #P message 763 446 31 196617 start;
> #P flonum 706 425 35 9 0.5 0 1 3 0 0 0 221 221 221 222 222 222 0 0 0;
> #P toggle 664 425 15 0;
> #P newex 664 445 52 196617 metro 30;
> #P message 827 446 31 196617 clear;
> #P newex 664 472 105 196617 jit.qt.movie 320 240;
> #P flonum 230 231 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
> #P message 230 252 42 196617 rate $1;
> #P message 116 230 30 196617 read;
> #P message 164 252 27 196617 stop;
> #P message 130 252 31 196617 start;
> #P flonum 71 231 35 9 0.5 0 1 3 0 0 0 221 221 221 222 222 222 0 0 0;
> #P toggle 29 231 15 0;
> #P newex 29 251 52 196617 metro 30;
> #P message 194 252 31 196617 clear;
> #P newex 29 278 105 196617 jit.qt.movie 320 240;
> #P toggle 82 100 15 0;
> #P message 82 120 68 196617 fullscreen $1;
> #N vpatcher 30 89 166 253;
> #P window setfont "Sans Serif" 9.;
> #P newex 50 71 35 196617 sel 27;
> #P newex 50 50 40 196617 key;
> #P outlet 50 93 15 0;
> #P connect 1 0 2 0;
> #P connect 2 0 0 0;
> #P pop;
> #P newobj 82 80 33 196617 p Esc;
> #P newex 82 138 84 196617 jit.window blend;
> #P toggle 29 73 42 0;
> #P newex 29 119 51 196617 qmetro 2;
> #P newex 29 165 237 196617 jit.gl.render blend @inherit_transform 2 @ortho 2;
> #P comment 777 541 62 196617 Base Image;
> #P connect 27 0 26 0;
> #P connect 22 0 20 1;
> #P fasten 35 0 34 0 725 563 669 563;
> #P connect 36 0 34 0;
> #P connect 18 0 36 0;
> #P fasten 20 0 18 0 669 470 669 470;
> #P fasten 19 0 18 0 832 467 669 467;
> #P fasten 23 0 18 0 768 467 669 467;
> #P fasten 24 0 18 0 802 467 669 467;
> #P fasten 25 0 18 0 756 467 669 467;
> #P fasten 26 0 18 0 865 467 669 467;
> #P connect 21 0 20 0;
> #P connect 50 0 49 0;
> #P connect 58 0 50 0;
> #P connect 56 0 57 0;
> #P connect 56 0 58 0;
> #P connect 48 0 47 0;
> #P connect 57 0 48 0;
> #P connect 46 0 42 4;
> #P connect 55 2 46 0;
> #P connect 62 0 59 3;
> #P connect 45 0 42 3;
> #P connect 55 1 45 0;
> #P connect 61 0 59 2;
> #P connect 60 0 59 1;
> #P connect 44 0 42 2;
> #P connect 55 0 44 0;
> #P connect 54 0 55 0;
> #P connect 39 0 54 0;
> #P connect 40 0 38 0;
> #P connect 8 0 32 0;
> #P fasten 8 0 41 0 34 468 73 468;
> #P fasten 8 0 40 0 34 307 308 307;
> #P connect 43 0 42 1;
> #P connect 17 0 16 0;
> #P connect 6 0 4 0;
> #P connect 7 0 6 0;
> #P connect 5 0 7 0;
> #P connect 12 0 10 1;
> #P connect 41 0 31 0;
> #P fasten 52 0 41 0 140 498 73 498;
> #P fasten 51 0 41 0 95 498 73 498;
> #P fasten 49 0 41 0 475 500 73 500;
> #P fasten 47 0 41 0 430 500 73 500;
> #P fasten 53 0 41 0 183 498 132 498 73 498;
> #P fasten 42 0 41 0 226 500 73 500;
> #P fasten 59 0 28 0 290 626 34 626;
> #P fasten 30 0 28 0 90 626 34 626;
> #P connect 33 0 28 0;
> #P connect 32 0 33 0;
> #P fasten 16 0 8 0 235 273 34 273;
> #P fasten 15 0 8 0 121 273 34 273;
> #P fasten 14 0 8 0 169 273 34 273;
> #P fasten 13 0 8 0 135 273 34 273;
> #P fasten 9 0 8 0 199 273 34 273;
> #P fasten 10 0 8 0 34 276 34 276;
> #P connect 11 0 10 0;
> #P connect 29 0 1 0;
> #P connect 2 0 29 0;
> #P connect 3 0 2 0;
> #P connect 1 0 37 0;
> #P window clipboard copycount 63;
>
>
>
> Thanks,
>
> Bart
>


Also, jit.gl.slab inherits the position attribute (but not rotate and

scale etc.) from being an ob3d (i.e. jit.gl.* ) object. It really

doesn't apply to a slab though so it has no effect.

Also, jit.gl.slab inherits the position attribute (but not rotate and
scale etc.) from being an ob3d (i.e. jit.gl.* ) object.  It really
doesn't apply to a slab though so it has no effect.

thx Wes, I got it to work (sort of) using the patch pasted below.

However it only works after I move the jit.window from one computer

monitor to the other. I assume I am missing an attribute somewhere...

When it doesn't work, the image appears to be just one flickering

thx Wes, I got it to work (sort of) using the patch pasted below.
However it only works after I move the jit.window from one computer
monitor to the other.  I assume I am missing an attribute somewhere...
 When it doesn't work, the image appears to be just one flickering
pixel that covers the entire window.

• error: jit.gl.texture: unable to create texture!

jit.gl.pbuffer: error binding texture: GL Error: Invalid operation

...but it's fairly common for me to see this in the max window -

especially with the slab help/example patches.

• error: jit.gl.texture: unable to create texture!
jit.gl.pbuffer: error binding texture: GL Error: Invalid operation

...but it's fairly common for me to see this in the max window -
especially with the slab help/example patches.

Ah - I thought I had the latest... it does seems to work okay now.

> I might recommend upgrading to the latest Jitter. This works for me

> perfectly on the latest Jitter with a mac book pro, nvidia 8600 and

> > • error: jit.gl.texture: unable to create texture!

> > jit.gl.pbuffer: error binding texture: GL Error: Invalid operation

> > ...but it's fairly common for me to see this in the max window -

> > especially with the slab help/example patches.

Ah - I thought I had the latest...  it does seems to work okay now.

On 8/12/07, Wesley Smith  wrote:
> I might recommend upgrading to the latest Jitter.  This works for me
> perfectly on the latest Jitter with a mac book pro, nvidia 8600 and
> the latest Jitter.Max.
>
> wes
>
> On 8/12/07, bart woodstrup  wrote:
> > My max window also tells me:
> >
> > • error: jit.gl.texture: unable to create texture!
> > jit.gl.pbuffer: error binding texture: GL Error: Invalid operation
> >
> > ...but it's fairly common for me to see this in the max window -
> > especially with the slab help/example patches.
> >
> > Max/Msp 4.6.3
> > Jitter  1.6.3 rc1
> >
> >
> > bart
> >
> >
>
>


> 2) Output using mode 1 of the chromakey shader to get just the alpha

> channel and use that as a mask for the video by sending both the

> original texture and the chromakey generated alpha channel to a

Do you mean it is possible to create the alpha channel for the video 

directly on the videoplane, without using a solution like 

jit.unpack/jit.pack to create the mask for the video?

This is a quick patch that shows what i used to do so far... is there a 

Wesley Smith wrote:
>
> 2) Output using mode 1 of the chromakey shader to get just the alpha
> channel and use that as a mask for the video by sending both the
> original texture and the chromakey generated alpha channel to a
> videoplane.

Hi,
Do you mean it is possible to create the alpha channel for the video 
directly on the videoplane, without using a solution like 
jit.unpack/jit.pack to create the mask for the video?

This is a quick patch that shows what i used to do so far... is there a 
better solution?

Do you suggest to use zl join to send a message like "jit_gl_texture 

I tried your patch, but I'm not sure I can make it working the right 

way: i get a video in the background (the first videoplane) and a second 

videoplane with a black square (the alpha channel that is created with 

the subpatch p.create.alpha)... so, why the "zl join"?

> #P newex 639 404 115 472055818 route jit_gl_texture;

> #P newex 501 380 128 472055818 jit.gl.texture mainout;

> #P newex 638 379 256 472055818 jit.gl.texture mainout @colormode lumalpha;

> #P newex 50 192 129 196617 jit.matrix 2 char 320 240;

> #P message 166 106 173 472055818 brgb 0 0 0 , frgb 255 255 255;

> #P message 125 133 260 472055818 clear , paintrect 20 100 186 175 255 255 255;

> #P newex 50 166 127 472055818 jit.lcd 4 char 320 240;

> #P newobj 638 339 89 472055818 p p.create-alpha;

> #P flonum 936 219 35 10 0 0 0 7203 0 0 0 221 221 221 222 222 222 0 0 0;

> #P flonum 887 219 35 10 0 0 0 7203 0 0 0 221 221 221 222 222 222 0 0 0;

> #P flonum 838 219 35 10 0 0 0 7203 0 0 0 221 221 221 222 222 222 0 0 0;

> #P newex 789 242 157 472055818 pak position 0. 0. 0.1;

> #P newex 632 464 268 472055818 jit.gl.videoplane mainout @scale 1.333

> 1. 1. @layer 1 @position 0. 0. 0.1 @blend_enable 1;

> #P newex 638 249 123 472055818 jit.qt.movie 320 240;

> #P newex 214 215 82 472055818 t b erase b b;

> #P newex 214 187 68 472055818 qmetro 40;

Do you suggest to use zl join to send a message like "jit_gl_texture 
[name] [name]" to the videoplane?

I tried your patch, but I'm not sure I can make it working the right 
way: i get a video in the background (the first videoplane) and a second 
videoplane with a black square (the alpha channel that is created with 
the subpatch p.create.alpha)... so, why the "zl join"?

Wesley Smith wrote:
> Yes, here's an example:
>
> wes
>
>
> #P window setfont Verdana 10.;
> #P window linecount 1;
> #P newex 633 437 43 472055818 zl join;
> #P newex 639 404 115 472055818 route jit_gl_texture;
> #P newex 501 380 128 472055818 jit.gl.texture mainout;
> #P newex 638 379 256 472055818 jit.gl.texture mainout @colormode lumalpha;
> #P window linecount 2;
> #N vpatcher 480 411 953 759;
> #P window setfont "Sans Serif" 9.;
> #P newex 50 192 129 196617 jit.matrix 2 char 320 240;
> #P window setfont Verdana 10.;
> #P newex 125 79 51 472055818 b 2;
> #P newex 125 43 62 472055818 loadbang;
> #P newex 50 96 26 472055818 b 1;
> #P message 166 106 173 472055818 brgb 0 0 0 , frgb 255 255 255;
> #P message 125 133 260 472055818 clear , paintrect 20 100 186 175 255 255 255;
> #P newex 50 166 127 472055818 jit.lcd 4 char 320 240;
> #P inlet 50 39 15 0;
> #P outlet 50 218 15 0;
> #P connect 1 0 5 0;
> #P connect 3 0 2 0;
> #P connect 4 0 2 0;
> #P connect 5 0 2 0;
> #P connect 2 0 8 0;
> #P connect 8 0 0 0;
> #P connect 6 0 7 0;
> #P connect 7 0 3 0;
> #P connect 7 1 4 0;
> #P pop;
> #P newobj 638 339 89 472055818 p p.create-alpha;
> #P flonum 936 219 35 10 0 0 0 7203 0 0 0 221 221 221 222 222 222 0 0 0;
> #P flonum 887 219 35 10 0 0 0 7203 0 0 0 221 221 221 222 222 222 0 0 0;
> #P flonum 838 219 35 10 0 0 0 7203 0 0 0 221 221 221 222 222 222 0 0 0;
> #P window linecount 1;
> #P newex 789 242 157 472055818 pak position 0. 0. 0.1;
> #P window linecount 2;
> #P newex 632 464 268 472055818 jit.gl.videoplane mainout @scale 1.333
> 1. 1. @layer 1 @position 0. 0. 0.1 @blend_enable 1;
> #P window linecount 1;
> #P message 655 212 35 472055818 read;
> #P newex 638 249 123 472055818 jit.qt.movie 320 240;
> #P newex 214 215 82 472055818 t b erase b b;
> #P toggle 214 163 15 0;
> #P newex 214 187 68 472055818 qmetro 40;
> #P message 371 208 35 472055818 read;
> #P newex 347 249 123 472055818 jit.qt.movie 320 240;
> #P newex 347 428 257 472055818 jit.gl.videoplane mainout @scale 1.333 1. 1.;
> #P window linecount 2;
> #P newex 214 333 117 472055818 jit.window mainout @depthbuffer 1;
> #P window linecount 3;
> #P newex 214 263 77 472055818 jit.gl.render mainout @ortho 2;
> #P user panel 779 200 207 87;
> #X brgb 255 240 157;
> #X frgb 0 0 0;
> #X border 1;
> #X rounded 0;
> #X shadow 0;
> #X done;
> #P connect 16 0 17 0;
> #P connect 17 0 19 0;
> #P connect 12 0 11 0;
> #P connect 20 0 11 0;
> #P connect 19 0 20 1;
> #P connect 18 0 20 0;
> #P connect 9 0 18 0;
> #P connect 9 0 16 0;
> #P connect 7 0 6 0;
> #P connect 6 0 8 0;
> #P connect 8 1 1 0;
> #P connect 8 0 1 0;
> #P fasten 8 2 4 0 267 244 352 244;
> #P connect 5 0 4 0;
> #P connect 4 0 3 0;
> #P fasten 8 3 9 0 291 239 643 239;
> #P connect 10 0 9 0;
> #P connect 13 0 12 1;
> #P connect 14 0 12 2;
> #P fasten 15 0 12 3 941 237 941 237;
> #P window clipboard copycount 21;
>
>

> Do you suggest to use zl join to send a message like "jit_gl_texture

> I tried your patch, but I'm not sure I can make it working the right

> way: i get a video in the background (the first videoplane) and a second

> videoplane with a black square (the alpha channel that is created with

> the subpatch p.create.alpha)... so, why the "zl join"?

Because it was easy to do. When I do it, I see a video in the

background and a subregion of a video in the foreground made from the

On 8/12/07, marco lorenzin  wrote:
> Hi,
>
> Do you suggest to use zl join to send a message like "jit_gl_texture
> [name] [name]" to the videoplane?
>

> I tried your patch, but I'm not sure I can make it working the right
> way: i get a video in the background (the first videoplane) and a second
> videoplane with a black square (the alpha channel that is created with
> the subpatch p.create.alpha)... so, why the "zl join"?
>

Because it was easy to do.  When I do it, I see a video in the
background and a subregion of a video in the foreground made from the
alpha mask.

> background and a subregion of a video in the foreground made from the

Sorry, it didn't work with my Windows XP, jitter 1.6.2 version. I've 

tried your patch with a mac, latest jitter, and it works great!

To justify myself, i can only say that multi-texturing is still an 

Wesley Smith wrote:
>When I do it, I see a video in the
> background and a subregion of a video in the foreground made from the
> alpha mask.

Sorry, it didn't work with my Windows XP, jitter 1.6.2  version. I've 
tried your patch with a mac, latest jitter, and it works great!
To justify myself, i can only say that multi-texturing is still an 
obscure and mysterious place for me!

There's one (or two) assumption(s) I was making that might cause problems.

1) In creating the alpha channel, I blindly send the jit.lcd output to

a 2 plane jitter matrix hoping it convert it properly. What you need

is a 2 plane matrix with the image in both planes. The alpha channel,

which is probably all white, could be getting through on windows but

2) I let the deafult multitexturing stuff do its thing with the

videoplane. For more precise and protable results, use a shader or

> > background and a subregion of a video in the foreground made from the

> Sorry, it didn't work with my Windows XP, jitter 1.6.2 version. I've

> tried your patch with a mac, latest jitter, and it works great!

> To justify myself, i can only say that multi-texturing is still an

1) In creating the alpha channel, I blindly send the jit.lcd output to
a 2 plane jitter matrix hoping it convert it properly.  What you need
is a 2 plane matrix with the image in both planes.  The alpha channel,
which is probably all white, could be getting through on windows but
not on the mac.

2) I let the deafult multitexturing stuff do its thing with the
videoplane.  For more precise and protable results, use a shader or
slab to blend the 2 images together.

On 8/12/07, marco lorenzin  wrote:
> Wesley Smith wrote:
> >When I do it, I see a video in the
> > background and a subregion of a video in the foreground made from the
> > alpha mask.
>
> Sorry, it didn't work with my Windows XP, jitter 1.6.2  version. I've
> tried your patch with a mac, latest jitter, and it works great!
> To justify myself, i can only say that multi-texturing is still an
> obscure and mysterious place for me!
>
> Wes, thanks a lot for your suggestion.
>
> M.
>
>


move a videoplane with chromakey and why position argument on a slab?