i'm happy to share with you my first attempt with a depth of field effect on gem. it's still very beta but it's working fine and i'm quite excited by the results. feedback is welcome as always.

note: i'll be releasing the slightly modified glsl code and the pd patch as soon as I get the permission from the author of the bokeh shader.

I was thinking how to implement a depth of field in Gem all this week ...Im not a shader expert so I was thinking of sending a 3d object to a pix buffer-using pix_blur and then another object in the foreground that wasn't blurred- sort of a layering technique

probably wouldn't of worked as well...:)

sorry for the delay, alpha release, updates and informations available here:
http://guidotamino.it/projects/depth-of-field/ (direct download)

the pd files are clean, commented and pretty self-explainatory. note: this has been tested *only* on osx 10.5.8 with pd 0.42.5 and gem 0.92.3, i don't really know what will happen on other platforms, please report bugs and comments.

many thanks to martins upitis for his bokeh shader. have fun!

I'll post back to let you know how it goes on my windows boxes. Cheers

0(12) : warning C7532: global type sampler2DRect requires "#version 140" or later
0(12) : warning C0000: ... or #extension GL_ARB_texture_rectangle : enable
0(31) : warning C7531: global function texture2DRect requires "#extension GL_ARB_texture_rectangle : enable" before use

But it may be my fault as I compiled GEM from svn on x86_64, and I'm not sure about gem's compilation options.

pob: let me know how it goes, i'm quite sure it's going to fall apart on windows.

rep: i updated the glsl code, the warning should be gone now. what's wrong with the blur masks? it's weird, they are plain jpg images.

dubtub and glitchpop: i'm planning to release some stuff soon. glsl is fast and it's actually easier to learn that it seems but the profound lack of documentation for that part in gem makes everything difficult. i guess this article might be a nice start to understand how glsl works, have a look. feel free to use the [pix_shader] abstraction when loading a shader in gem, it's nothing fancy but it makes the task even easier.

I spent the afternoon yesterday and got it to run on Windows and adapted the code to have a webcam as a depth texture.
Had a problem with [text3D]. I also have problems with [pix_image] - All GEM related. I should try on an earlier version of GEM to see if it solves anything.

edit. Now fixed. Had to remove a dll to disable imagemagick.

edit: New version below, closer to the original patch.

1. why are you setting the color of the framebuffer to 0.3 0.3 0.3?

2. is it really necessary to put everything under a single gemhead? why is that? i find all that crazy retriggering to be counterintuitive. i see you also had to put the render order in the gemhead, is this a windows thing?

3. what's wrong with [text3d]? maybe you can add an entry to the bug tracker.

A single [gemhead] with a [t a a ...] is good to know what is rendered in what order.
The number in the [gemhead] is good to know what is rendered in what order as well.
First the are rendered the positive numbers in increasing order (ie. first 1 then 2) then the negative numbers in decreasing order (ie. first -1 then -2). This is not specific to Windows.
Otherwise I think it's the patching order that defines what is rendered first and so on. I find this to be very confusing since you can't really see the order and it can be easily disrupted.
I've noticed that [gemhead] in subpatches are rendered out of order too, even with a numbered [gemhead]. Probably related to the order of creation of the subpatches there too.

I got rid of [text3d] because otherwise I couldn't use your patch. Feel free to put them back if you want. I think it crashes because it can't find the font. But this is more or less erratic depending on the version of GEM and Pd. We discussed this with IOhannes on IRC yesterday. He suggested this was related to the font not being found. Maybe including a font in the patch folder and specifying it to [text3d] would solve this issue.

about the [gemhead] priority I know it's not specific to windows, I was just wondering why it is necessary on windows while it is working out of the box in osx and linux.

no worries for the text3d, i was just curious. i'll see what to do with that in the next "release". is [text2d] working maybe?

Anyway, thanks again for patching all this together. I already have it in a big performance patch. I have to try working with it now.
Cheers

I also got rid of the color setting in one of the framebuffers.
texunit 0 seemed to be used by some other [gemframebuffer] (the ones with the blur shader) so I used texunit3 instead, but this may not be relevant.

http://www.pdpatchrepo.info/hurleur/depth_of_field_pob.zip

an handy abstraction to use this effect will be the next step.