marius.schebella

I just subscribed to the jitter list, trying to test a shader but 

something is wrong. I hope it is ok, if I just paste it.

I have to say that this is my first shader, so it could be some very 

basic problem with bindings or jitter communication.

anyway, when I try to load the shader I get:

setting GLSL param: GL Error: Invalid operation

    Shader to set alpha related to color thresholds

hey,
I just subscribed to the jitter list, trying to test a shader but 
something is wrong. I hope it is ok, if I just paste it.
I have to say that this is my first shader, so it could be some very 
basic problem with bindings or jitter communication.
anyway, when I try to load the shader I get:
setting GLSL param: GL Error: Invalid operation
thanks for help,
marius.

	Shader to set alpha related to color thresholds

first-shader

> I just subscribed to the jitter list, trying to test a shader but

> something is wrong. I hope it is ok, if I just paste it.

> I have to say that this is my first shader, so it could be some very

> basic problem with bindings or jitter communication.

> anyway, when I try to load the shader I get:

> setting GLSL param: GL Error: Invalid operation

> Shader to set alpha related to color thresholds

vec4 A = texture2DRect(image, texcoord);
    A.a = pass_other[0];

  vec4 A = texture2DRect(image, texcoord);
    A.a = pass_other.x;

On 11/8/07, marius schebella  wrote:
> hey,
> I just subscribed to the jitter list, trying to test a shader but
> something is wrong. I hope it is ok, if I just paste it.
> I have to say that this is my first shader, so it could be some very
> basic problem with bindings or jitter communication.
> anyway, when I try to load the shader I get:
> setting GLSL param: GL Error: Invalid operation
> thanks for help,
> marius.
>
> ---------
>
>         Shader to set alpha related to color thresholds
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>


your problem is most likely in this line:

Change type to "int" and you will probably be okay.

FWIW, I would recommend ditching all of that conditional stuff (if...) 

and replacing with mix() and step() type functions. Support for 

conditional statements is pretty unpredictable in GLSL.

FWIW, I would recommend ditching all of that conditional stuff (if...) 
and replacing with mix() and step() type functions.  Support for 
conditional statements is pretty unpredictable in GLSL.

I think I have a problem in my max patch, because

does not look transparent. (A.r, A.g, A.b all work.)

do I need a special object or argument to turn alphachannel computation 

on? sorry if that is a basic question. right now I am only using 

jit.qt.movie, jit.gl.slab and jit.gl.videoplane.

> vec4 A = texture2DRect(image, texcoord);

>> I just subscribed to the jitter list, trying to test a shader but

>> something is wrong. I hope it is ok, if I just paste it.

>> I have to say that this is my first shader, so it could be some very

>> basic problem with bindings or jitter communication.

>> anyway, when I try to load the shader I get:

>> setting GLSL param: GL Error: Invalid operation

>> Shader to set alpha related to color thresholds

thank you for the quick reply.
I think I have a problem in my max patch, because
even
void main()
{
     vec4 A = texture2DRect(image, texcoord);
     A.a = 0.4;
     gl_FragColor = A;
}
does not look transparent. (A.r, A.g, A.b all work.)
do I need a special object or argument to turn alphachannel computation 
on? sorry if that is a basic question. right now I am only using 
jit.qt.movie,  jit.gl.slab and jit.gl.videoplane.
thanks,
marius.

Wesley Smith wrote:
>   vec4 A = texture2DRect(image, texcoord);
>     A.a = pass_other[0];
>
> this should be :
>
>   vec4 A = texture2DRect(image, texcoord);
>     A.a = pass_other.x;
>
> wes
>
> On 11/8/07, marius schebella  wrote:
>> hey,
>> I just subscribed to the jitter list, trying to test a shader but
>> something is wrong. I hope it is ok, if I just paste it.
>> I have to say that this is my first shader, so it could be some very
>> basic problem with bindings or jitter communication.
>> anyway, when I try to load the shader I get:
>> setting GLSL param: GL Error: Invalid operation
>> thanks for help,
>> marius.
>>
>> ---------
>>
>>         Shader to set alpha related to color thresholds
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>


I read that glsl is not optimized for conditional stuff, but I have to 

learn more glsl commands to see what could replace them.

the thing is, I only want a comparison of 3 of the 4 channels. yes, I 

would like to boost efficiency by using glsl internal commands.

> your problem is most likely in this line:

> Change type to "int" and you will probably be okay.

> FWIW, I would recommend ditching all of that conditional stuff (if...) 

> and replacing with mix() and step() type functions. Support for 

> conditional statements is pretty unpredictable in GLSL.

hello andrew,
thanks, that solved one of the problems
I read that glsl is not optimized for conditional stuff, but I have to 
learn more glsl commands to see what could replace them.
the thing is, I only want a comparison of 3 of the 4 channels. yes, I 
would like to boost efficiency by using glsl internal commands.
marius.

andrew benson wrote:
> your problem is most likely in this line:
>
>
>
> Change type to "int" and you will probably be okay.
>
> FWIW, I would recommend ditching all of that conditional stuff (if...) 
> and replacing with mix() and step() type functions.  Support for 
> conditional statements is pretty unpredictable in GLSL.
>
> Best,
> Andrew B.
>


make sure your output geometry has blend_enable 1 ;

sosomething like jit.gl.videoplane context @blend_enable 1

On Nov 8, 2007, at 2:19 PM, marius schebella wrote:

> I think I have a problem in my max patch, because

> does not look transparent. (A.r, A.g, A.b all work.)

> do I need a special object or argument to turn alphachannel 

> computation on? sorry if that is a basic question. right now I am 

> only using jit.qt.movie, jit.gl.slab and jit.gl.videoplane.

>> vec4 A = texture2DRect(image, texcoord);

>>> I just subscribed to the jitter list, trying to test a shader but

>>> something is wrong. I hope it is ok, if I just paste it.

>>> I have to say that this is my first shader, so it could be some very

>>> basic problem with bindings or jitter communication.

>>> anyway, when I try to load the shader I get:

>>> setting GLSL param: GL Error: Invalid operation

>>> Shader to set alpha related to color 

> thank you for the quick reply.
> I think I have a problem in my max patch, because
> even
> void main()
> {
>    vec4 A = texture2DRect(image, texcoord);
>    A.a = 0.4;
>    gl_FragColor = A;
> }
> does not look transparent. (A.r, A.g, A.b all work.)
> do I need a special object or argument to turn alphachannel  
> computation on? sorry if that is a basic question. right now I am  
> only using jit.qt.movie,  jit.gl.slab and jit.gl.videoplane.
> thanks,
> marius.
>
> Wesley Smith wrote:
>>  vec4 A = texture2DRect(image, texcoord);
>>    A.a = pass_other[0];
>> this should be :
>>  vec4 A = texture2DRect(image, texcoord);
>>    A.a = pass_other.x;
>> wes
>> On 11/8/07, marius schebella  wrote:
>>> hey,
>>> I just subscribed to the jitter list, trying to test a shader but
>>> something is wrong. I hope it is ok, if I just paste it.
>>> I have to say that this is my first shader, so it could be some very
>>> basic problem with bindings or jitter communication.
>>> anyway, when I try to load the shader I get:
>>> setting GLSL param: GL Error: Invalid operation
>>> thanks for help,
>>> marius.
>>>
>>> ---------
>>>
>>>        Shader to set alpha related to color  
>>> thresholds
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>


> thanks, that solved one of the problems

> I read that glsl is not optimized for conditional stuff, but I have to

> learn more glsl commands to see what could replace them.

> the thing is, I only want a comparison of 3 of the 4 channels. yes, I

> would like to boost efficiency by using glsl internal commands.

> > your problem is most likely in this line:

> > Change type to "int" and you will probably be okay.

> > FWIW, I would recommend ditching all of that conditional stuff (if...)

> > and replacing with mix() and step() type functions. Support for

> > conditional statements is pretty unpredictable in GLSL.

On 11/8/07, marius schebella  wrote:
> hello andrew,
> thanks, that solved one of the problems
> I read that glsl is not optimized for conditional stuff, but I have to
> learn more glsl commands to see what could replace them.
> the thing is, I only want a comparison of 3 of the 4 channels. yes, I
> would like to boost efficiency by using glsl internal commands.
> marius.
>
> andrew benson wrote:
> > your problem is most likely in this line:
> >
> >
> >
> > Change type to "int" and you will probably be okay.
> >
> > FWIW, I would recommend ditching all of that conditional stuff (if...)
> > and replacing with mix() and step() type functions.  Support for
> > conditional statements is pretty unpredictable in GLSL.
> >
> > Best,
> > Andrew B.
> >
>
>


btw, marius, does the gem list know you're over here in segmented patch cord land?

thanks to josh, rob, vade, wes and andrew, I posted the unspectular 

http://www.parasitaere-kapazitaeten.net/max_msp/pix_alpha

I outsourced the vert and frag programs to extra files and replaced my 

if all(greaterThanEqual(A.rgb,lothresh.rgb)...

> btw, marius, does the gem list know you're over here in segmented patch cord land?

naaahh! all these open source freaks are totally ignorant and 

insensitive to the beauties of segmented patchcord land...

ok,
thanks to josh, rob, vade, wes and andrew, I posted the unspectular 
result at http://www.parasitaere-kapazitaeten.net/max_msp/pix_alpha (in 
case someone wants to check).
I outsourced the vert and frag programs to extra files and replaced my 
original comparators with glsl native
if all(greaterThanEqual(A.rgb,lothresh.rgb)...

naaahh! all these open source freaks are totally ignorant and 
insensitive to the beauties of segmented patchcord land...