Brecht

I've finally started looking into glsl, and intrigued by the 

chromatic aberration shader I tried implementing it from the orange 

but, here goes, of course it doesn't work ;)

It's probably something stupid, or maybe it's completely and utterly 

I get 'undeclared identifier' errors in the max window.

I've finally started looking into glsl, and intrigued by the  
chromatic aberration shader I tried implementing it from the orange  
book...
but, here goes, of course it doesn't work ;)
It's probably something stupid, or maybe it's completely and utterly  
wrong...
I get  'undeclared identifier' errors in the max window.

Brecht Debackere
www.autofasurer.net
M+32(0)498319302
F+32(0)70429559
Skype : Bdebackere
brecht@visualantics.net


chromatic-aberration-shader

I do not believe you are allowed to set parameter defaults to formulas :

Do this math in the shader, or outside of it.

Also, typically jitter binds the textures within the shader to 

and lastly but most importantly, you are not, as far as I can see, 

specifying gl_FragColor, which is reqired in a fragment program to 

tell the GPU what your output color is. In fact, it seems as though 

you do not have a fragment program at all.

On Sep 20, 2007, at 6:26 AM, Brecht Debackere wrote:

> I've finally started looking into glsl, and intrigued by the 

> chromatic aberration shader I tried implementing it from the orange 

> but, here goes, of course it doesn't work ;)

> It's probably something stupid, or maybe it's completely and 

> I get 'undeclared identifier' errors in the max window.

I do not believe you are allowed to set parameter defaults to formulas :
>

Also, typically jitter binds the textures within the shader to  
texture units via

and lastly but most importantly, you are not, as far as I can see,  
specifying gl_FragColor, which is reqired in a fragment program to  
tell the GPU what your output color is. In fact, it seems as though  
you do not have a fragment program at all.

> Hi all,
>
> I've finally started looking into glsl, and intrigued by the  
> chromatic aberration shader I tried implementing it from the orange  
> book...
> but, here goes, of course it doesn't work ;)
> It's probably something stupid, or maybe it's completely and  
> utterly wrong...
> I get  'undeclared identifier' errors in the max window.
>
>
>
>
> 	Chromatic Aberration 	
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
> Brecht Debackere
> www.autofasurer.net
> M+32(0)498319302
> F+32(0)70429559
> Skype : Bdebackere
> brecht@visualantics.net
>
>
>

...You live and learn. At any rate, you live.

> I do not believe you are allowed to set parameter defaults to 

> Do this math in the shader, or outside of it.

> Also, typically jitter binds the textures within the shader to 

> and lastly but most importantly, you are not, as far as I can see, 

> specifying gl_FragColor, which is reqired in a fragment program to 

> tell the GPU what your output color is. In fact, it seems as though 

> you do not have a fragment program at all.

> On Sep 20, 2007, at 6:26 AM, Brecht Debackere wrote:

>> I've finally started looking into glsl, and intrigued by the 

>> chromatic aberration shader I tried implementing it from the 

>> but, here goes, of course it doesn't work ;)

>> It's probably something stupid, or maybe it's completely and 

>> I get 'undeclared identifier' errors in the max window.

right. back to the drawing board :)
thanks for the explanation...
...You live and learn. At any rate, you live.
On 20 Sep 2007, at 18:42, vade wrote:

> Hi.
>
> A few things
>
> I do not believe you are allowed to set parameter defaults to  
> formulas :
>>
>
> Do this math in the shader, or outside of it.
>
> Also, typically jitter binds the textures within the shader to  
> texture units via
>
>
>
> (for zeroth texture unit)
>
> and lastly but most importantly, you are not, as far as I can see,  
> specifying gl_FragColor, which is reqired in a fragment program to  
> tell the GPU what your output color is. In fact, it seems as though  
> you do not have a fragment program at all.
>
>
> On Sep 20, 2007, at 6:26 AM, Brecht Debackere wrote:
>
>> Hi all,
>>
>> I've finally started looking into glsl, and intrigued by the  
>> chromatic aberration shader I tried implementing it from the  
>> orange book...
>> but, here goes, of course it doesn't work ;)
>> It's probably something stupid, or maybe it's completely and  
>> utterly wrong...
>> I get  'undeclared identifier' errors in the max window.
>>
>>
>>
>>
>> 	Chromatic Aberration 	
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> Brecht Debackere
>> www.autofasurer.net
>> M+32(0)498319302
>> F+32(0)70429559
>> Skype : Bdebackere
>> brecht@visualantics.net
>>
>>
>>
>
> v a d e //
>
> www.vade.info
> abstrakt.vade.info
>
>
>

www.autofasurer.net
M+32(0)498319302
F+32(0)70429559
Skype : Bdebackere
brecht@visualantics.net


Apologies for digging up this old thread. I've finally continued my 

dabbling with glsl, still the same one from the orange book.

I've started anew and so far came up with nothing much except for 

trying to fit the code into the .jxs format. In the end I'm trying to 

find figure out how the examples in the orange book translate to jitter.

Surprisingly, it's not working ;) Any shader guru's willing to stare 

Apologies for digging up this old thread. I've finally continued my  
dabbling with glsl, still the same one from the orange book.
I've started anew and so far came up with nothing much except for  
trying to fit the code into the .jxs format. In the end I'm trying to  
find figure out how the examples in the orange book translate to jitter.

Surprisingly, it's not working ;) Any shader guru's willing to stare  
into this mess?

I *believe* this is not working because Jitter 1.7, to my knowledge, does not support "uniform samplerCube Cubemap". I could be mistaken though.

On Tue, Jun 10, 2008 at 11:12 PM, vade wrote:

> I *believe* this is not working because Jitter 1.7, to my knowledge, does not support "uniform samplerCube Cubemap". I could be mistaken though.

Actually, one of the new things in Jitter 1.7 is cubemap support. See

jit.gl.cubemap's help for more on this. As an example shader, here's

a Fresnel shader that mixes reflection and refraction based on the

    Environment Mapping with a Cube Map

On Tue, Jun 10, 2008 at 11:12 PM, vade  wrote:
>
> I *believe* this is not working because Jitter 1.7, to my knowledge, does not support "uniform samplerCube Cubemap". I could be mistaken though.
>

Actually, one of the new things in Jitter 1.7 is cubemap support.  See
jit.gl.cubemap's help for more on this.  As an example shader, here's
a Fresnel shader that mixes reflection and refraction based on the
angle of a ray hitting the object:

I'm not sure why you're multiplying the refractino vector by the

gl_TextureMatrix. I think this might be your problem. See the shader

I just posted as it does most of what you want. You'll just have to

move some things from the fragment shader to the vertex shader.

I'm not sure why you're multiplying the refractino vector by the
gl_TextureMatrix.  I think this might be your problem.  See the shader
I just posted as it does most of what you want.  You'll just have to
move some things from the fragment shader to the vertex shader.

Thanks guys. I'll scrutinize that shader.

To elaborate on the gl_TextureMatrix : this code is literally from 

the orange book. That's what I'm trying to find out: how to get the 

On 11 Jun 2008, at 08:42, Wesley Smith wrote:

> I'm not sure why you're multiplying the refractino vector by the

> gl_TextureMatrix. I think this might be your problem. See the shader

> I just posted as it does most of what you want. You'll just have to

> move some things from the fragment shader to the vertex shader.

Thanks guys. I'll scrutinize that shader.
To elaborate on the gl_TextureMatrix : this code is literally from  
the orange book. That's what I'm trying to find out: how to get the  
examples in there to work.

> I'm not sure why you're multiplying the refractino vector by the
> gl_TextureMatrix.  I think this might be your problem.  See the shader
> I just posted as it does most of what you want.  You'll just have to
> move some things from the fragment shader to the vertex shader.
>
> wes


On Mon, Jun 9, 2008 at 12:51 PM, Brecht Debackere 

> Apologies for digging up this old thread. I've finally continued my

> dabbling with glsl, still the same one from the orange book.

> I've started anew and so far came up with nothing much except for trying to

> fit the code into the .jxs format. In the end I'm trying to find figure out

> how the examples in the orange book translate to jitter.

> Surprisingly, it's not working ;) Any shader guru's willing to stare into

I also copied the chromatic Aberration shader from the Orange Book and can

get a result in Jitter. However, when I copy the code from your post I get

a compilation error when I try to use it. I seem to remember trying a

shader that you posted previously (?) but had the same result. I looked at

the code and couldn't find any difference between your version and mine but

Whenever I copy code from a browser I get rid of hidden formatting (by

selecting zap gremlins in text wrangler), sometimes this can interfere with

the code when it gets compiled. Also, I've found that my graphics card

doesn't support some shaders. You might want to check that yours supports

Anyway, here's a version of the same shader that I did to try and understand

what was happening. I simply changed the varying variables to uniform ones

that can be altered from Jitter. If you can get it to work it might help to

demonstrate how to draw up the jxs files for Jitter.

On Mon, Jun 9, 2008 at 12:51 PM, Brecht Debackere 
wrote:

> Apologies for digging up this old thread. I've finally continued my
> dabbling with glsl, still the same one from the orange book.
> I've started anew and so far came up with nothing much except for trying to
> fit the code into the .jxs format. In the end I'm trying to find figure out
> how the examples in the orange book translate to jitter.
>
> Surprisingly, it's not working ;) Any shader guru's willing to stare into
> this mess?
>

I also copied the chromatic Aberration shader from the Orange Book and can
get a result in Jitter.  However, when I copy the code from your post I get
a compilation error when I try to use it.  I seem to remember trying a
shader that you posted previously (?) but had the same result. I looked at
the code and couldn't find any difference between your version and mine but
put it down to not looking hard enough.
Whenever I copy code from a browser I get rid of hidden formatting (by
selecting zap gremlins in text wrangler), sometimes this can interfere with
the code when it gets compiled.  Also, I've found that my graphics card
doesn't support some shaders.  You might want to check that yours supports
the gl and shading code that you use.

Anyway, here's a version of the same shader that I did to try and understand
what was happening.  I simply changed the varying variables to uniform ones
that can be altered from Jitter.  If you can get it to work it might help to
demonstrate how to draw up the jxs files for Jitter.

great! I get no more errors at least with yours. I might 've made 

some typo's along the way since I copied it manually from the book.

There are still some things I don't fully understand though, since it 

only seems to color my object black; the cubemap e.g. where should it 

> On Mon, Jun 9, 2008 at 12:51 PM, Brecht Debackere 

> Apologies for digging up this old thread. I've finally continued my 

> I've started anew and so far came up with nothing much except for 

> trying to fit the code into the .jxs format. In the end I'm trying 

> to find figure out how the examples in the orange book translate to 

> Surprisingly, it's not working ;) Any shader guru's willing to 

> I also copied the chromatic Aberration shader from the Orange Book 

> and can get a result in Jitter. However, when I copy the code from 

> your post I get a compilation error when I try to use it. I seem 

> to remember trying a shader that you posted previously (?) but had 

> the same result. I looked at the code and couldn't find any 

> difference between your version and mine but put it down to not 

> Whenever I copy code from a browser I get rid of hidden formatting 

> (by selecting zap gremlins in text wrangler), sometimes this can 

> interfere with the code when it gets compiled. Also, I've found 

> that my graphics card doesn't support some shaders. You might want 

> to check that yours supports the gl and shading code that you use.

> Anyway, here's a version of the same shader that I did to try and 

> understand what was happening. I simply changed the varying 

> variables to uniform ones that can be altered from Jitter. If you 

> can get it to work it might help to demonstrate how to draw up the 

great! I get no more errors at least with yours. I might 've made  
some typo's along the way since I copied it manually from the book.
There are still some things I don't fully understand though, since it  
only seems to color my object black; the cubemap e.g. where should it  
come from?

> On Mon, Jun 9, 2008 at 12:51 PM, Brecht Debackere  
>  wrote:
> Apologies for digging up this old thread. I've finally continued my  
> dabbling with glsl, still the same one from the orange book.
> I've started anew and so far came up with nothing much except for  
> trying to fit the code into the .jxs format. In the end I'm trying  
> to find figure out how the examples in the orange book translate to  
> jitter.
>
> Surprisingly, it's not working ;) Any shader guru's willing to  
> stare into this mess?
>
> I also copied the chromatic Aberration shader from the Orange Book  
> and can get a result in Jitter.  However, when I copy the code from  
> your post I get a compilation error when I try to use it.  I seem  
> to remember trying a shader that you posted previously (?) but had  
> the same result. I looked at the code and couldn't find any  
> difference between your version and mine but put it down to not  
> looking hard enough.
>
> Whenever I copy code from a browser I get rid of hidden formatting  
> (by selecting zap gremlins in text wrangler), sometimes this can  
> interfere with the code when it gets compiled.  Also, I've found  
> that my graphics card doesn't support some shaders.  You might want  
> to check that yours supports the gl and shading code that you use.
>
> Anyway, here's a version of the same shader that I did to try and  
> understand what was happening.  I simply changed the varying  
> variables to uniform ones that can be altered from Jitter.  If you  
> can get it to work it might help to demonstrate how to draw up the  
> jxs files for Jitter.
>
> pelado
>
>
>
>
>
>
>
>
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>
>
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>
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>
>


you need to place a jit.gl.cubemap object in your patch and import some

textures to get a result. See the cubemap help file.

On Wed, Jun 11, 2008 at 5:35 PM, Brecht Debackere 

> great! I get no more errors at least with yours. I might 've made some

> typo's along the way since I copied it manually from the book.

> There are still some things I don't fully understand though, since it only

> seems to color my object black; the cubemap e.g. where should it come from?

> On 11 Jun 2008, at 17:27, pelado wrote:

>> Apologies for digging up this old thread. I've finally continued my

>> dabbling with glsl, still the same one from the orange book.

>> I've started anew and so far came up with nothing much except for trying

>> to fit the code into the .jxs format. In the end I'm trying to find figure

>> out how the examples in the orange book translate to jitter.

>> Surprisingly, it's not working ;) Any shader guru's willing to stare into

> I also copied the chromatic Aberration shader from the Orange Book and can

> get a result in Jitter. However, when I copy the code from your post I get

> a compilation error when I try to use it. I seem to remember trying a

> shader that you posted previously (?) but had the same result. I looked at

> the code and couldn't find any difference between your version and mine but

> put it down to not looking hard enough.

> Whenever I copy code from a browser I get rid of hidden formatting (by

> selecting zap gremlins in text wrangler), sometimes this can interfere with

> the code when it gets compiled. Also, I've found that my graphics card

> doesn't support some shaders. You might want to check that yours supports

> Anyway, here's a version of the same shader that I did to try and

> understand what was happening. I simply changed the varying variables to

> uniform ones that can be altered from Jitter. If you can get it to work it

> might help to demonstrate how to draw up the jxs files for Jitter.

you need to place a jit.gl.cubemap object in your patch and import some
textures to get a result.  See the cubemap  help file.
pelado

On Wed, Jun 11, 2008 at 5:35 PM, Brecht Debackere 
wrote:

> great! I get no more errors at least with yours. I might 've made some
> typo's along the way since I copied it manually from the book.
> There are still some things I don't fully understand though, since it only
> seems to color my object black; the cubemap e.g. where should it come from?
>
>
>
> On 11 Jun 2008, at 17:27, pelado wrote:
>
> On Mon, Jun 9, 2008 at 12:51 PM, Brecht Debackere 
> wrote:
>
>> Apologies for digging up this old thread. I've finally continued my
>> dabbling with glsl, still the same one from the orange book.
>> I've started anew and so far came up with nothing much except for trying
>> to fit the code into the .jxs format. In the end I'm trying to find figure
>> out how the examples in the orange book translate to jitter.
>>
>> Surprisingly, it's not working ;) Any shader guru's willing to stare into
>> this mess?
>>
>
> I also copied the chromatic Aberration shader from the Orange Book and can
> get a result in Jitter.  However, when I copy the code from your post I get
> a compilation error when I try to use it.  I seem to remember trying a
> shader that you posted previously (?) but had the same result. I looked at
> the code and couldn't find any difference between your version and mine but
> put it down to not looking hard enough.
> Whenever I copy code from a browser I get rid of hidden formatting (by
> selecting zap gremlins in text wrangler), sometimes this can interfere with
> the code when it gets compiled.  Also, I've found that my graphics card
> doesn't support some shaders.  You might want to check that yours supports
> the gl and shading code that you use.
>
> Anyway, here's a version of the same shader that I did to try and
> understand what was happening.  I simply changed the varying variables to
> uniform ones that can be altered from Jitter.  If you can get it to work it
> might help to demonstrate how to draw up the jxs files for Jitter.
>
> pelado
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>

The cubemap is a texture like any other Jitter texture. In this case

though it's specifically jit.gl.cubemap which can be used just like

jit.gl.texture but binds as a Cube Sampler instead.

On Wed, Jun 11, 2008 at 8:35 AM, Brecht Debackere

> Anyway, here's a version of the same shader that I did to try and understand

> what was happening. I simply changed the varying variables to uniform ones

> that can be altered from Jitter. If you can get it to work it might help to

> demonstrate how to draw up the jxs files for Jitter.

The cubemap is a texture like any other Jitter texture.  In this case
though it's specifically jit.gl.cubemap which can be used just like
jit.gl.texture but binds as a Cube Sampler instead.

On Wed, Jun 11, 2008 at 8:35 AM, Brecht Debackere
 wrote:
> great! I get no more errors at least with yours. I might 've made some
> typo's along the way since I copied it manually from the book.
> There are still some things I don't fully understand though, since it only
> seems to color my object black; the cubemap e.g. where should it come from?
>
>
>
> On 11 Jun 2008, at 17:27, pelado wrote:
>
> On Mon, Jun 9, 2008 at 12:51 PM, Brecht Debackere 
> wrote:
>>
>> Apologies for digging up this old thread. I've finally continued my
>> dabbling with glsl, still the same one from the orange book.
>> I've started anew and so far came up with nothing much except for trying
>> to fit the code into the .jxs format. In the end I'm trying to find figure
>> out how the examples in the orange book translate to jitter.
>>
>> Surprisingly, it's not working ;) Any shader guru's willing to stare into
>> this mess?
>
> I also copied the chromatic Aberration shader from the Orange Book and can
> get a result in Jitter.  However, when I copy the code from your post I get
> a compilation error when I try to use it.  I seem to remember trying a
> shader that you posted previously (?) but had the same result. I looked at
> the code and couldn't find any difference between your version and mine but
> put it down to not looking hard enough.
> Whenever I copy code from a browser I get rid of hidden formatting (by
> selecting zap gremlins in text wrangler), sometimes this can interfere with
> the code when it gets compiled.  Also, I've found that my graphics card
> doesn't support some shaders.  You might want to check that yours supports
> the gl and shading code that you use.
> Anyway, here's a version of the same shader that I did to try and understand
> what was happening.  I simply changed the varying variables to uniform ones
> that can be altered from Jitter.  If you can get it to work it might help to
> demonstrate how to draw up the jxs files for Jitter.
> pelado
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>


I'm very interested in experimenting with Chromatic Aberration effects, but I dont know much about writing/implementing shaders yet.. -

- is there any chance you could post an example patch with this CA Shader working?

I'm very interested in experimenting with Chromatic Aberration effects, but I dont know much about writing/implementing shaders yet.. - 

 - is there any chance you could post an example patch with this CA Shader working?
thanks!


I started trying to convert the shader myself, but I know that I haven't gotten it quite right yet, I read in this thread that theres something with the cube mapping that has to be done in jitter but I dont fully understand how to do that. Im posting the version of the shader that I have partially converted, though I know its not quite right yet. Is it possible for someone to post a proper working version and show me what it is I am doing wrong.

I started trying to convert the shader myself, but I know that I haven't gotten it quite right yet, I read in this thread that theres something with the cube mapping that has to be done in jitter but I dont fully understand how to do that.  Im posting the version of the shader that I have partially converted, though I know its not quite right yet.  Is it possible for someone to post a proper working version and show me what it is I am doing wrong.


robtherich posted a great fixed version of my poor attempt on here:

https://cycling74.com/forums/index.php?t=msg&th=37541&start=0&rid=0&S=6cd237d50d8f58e65c14a96f4a604e65

Man what a great shader! I thirst for more!!

Man what a great shader!  I thirst for more!!

Chromatic Aberration Shader