Reverse Trompe-l'oeil

Ronounours · **Joined:** Jan 03, 2011 **Posts:** 1656

Hi there,

I was playing today with some scripts to create animated GIF, and had an idea, which could be considered as a 'Reverse Trompe-l'oeil' effect :p
According to Wikipedia, a Trompe-l'oeil is a 2d picture that creates the optical illusion of having 3d objects in front of the viewer.
Here, I propose to do exactly the opposite, which is creating a 3d object that creates the optical illusion of having a simple 2d shape, when rendered on an image (and of course, the 2d shape is not present as it, in the 3d object).

For this purpose, I've created another G'MIC script that create a random-looking 3d object, but when it is rendered at two specific view angles, the viewer has the impression to see regular 2d texts (here, I used 'GIMP' and 'Chat' of course :jumpclap

).
Once the object is created, I just have to map some random texture on it, and create a 3d motion that interpolates between these 2 particular angles.

Here is the result :

Hope you'll like it. Personally, I do ! As you can see, I'm not an artist, I only know how to code graphical stuffs. But even in this case, we can have some inspiration sometimes

molly · **Joined:** Apr 07, 2010 **Posts:** 14182

That is so very cool. I like it too.

Erisian · **Posted:** Sat Sep 01, 2012 8:16 am **(#3)**

I really like that one. Nice work.

:ninja

- Thanx Mo.

Ronounours · **Joined:** Jan 03, 2011 **Posts:** 1656

The cool thing with being a programmer, is that you can only change a parameter an get a new rendering easily, without spending hours in pixels manipulation :p
Thanks molly !

samj · **Joined:** May 09, 2012 **Posts:** 914

This is a very nice feature :jumpclap

molly · **Joined:** Apr 07, 2010 **Posts:** 14182

Ronounours wrote:

The cool thing with being a programmer, is that you can only change a parameter an get a new rendering easily, without spending hours in pixels manipulation :p
Thanks molly !

Wow that is so cool David. Thanks :yes

Erisian · **Posted:** Sat Sep 01, 2012 10:41 am **(#7)**

Ronounours wrote:

The cool thing with being a programmer, is that you can only change a parameter an get a new rendering easily, without spending hours in pixels manipulation :p
Thanks molly !

You're a genius David. Can you do the impossible as well?

Esper · **Joined:** Jul 17, 2012 **Posts:** 2769

its magic ! :mrgreen:

Attachment:

2984604_640px.jpg [ 45.35 KiB | Viewed 6329 times ]

Attachment:

reality.jpg [ 73.71 KiB | Viewed 6321 times ]

Ronounours · **Joined:** Jan 03, 2011 **Posts:** 1656

@Erisian : Of course I can !

Ronounours · **Joined:** Jan 03, 2011 **Posts:** 1656

And here is variation of the famous Yes/No sculpture

Here is mine (more complicated to make for real, unfortunately :p)

GnuTux · **Posted:** Sat Sep 01, 2012 1:20 pm **(#11)**

That's a way cool effect, Ronounours.

Also, I really like your new avatar. :yes

2-ton · **Posted:** Sat Sep 01, 2012 7:23 pm **(#12)**

That is super cool!

Odinbc · **Posted:** Sat Sep 01, 2012 7:31 pm **(#13)**

Another winner, David :bigthup

The scripts keep coming. I'm out of breath trying to keep up with you!

Oregonian · **Posted:** Sat Sep 01, 2012 8:02 pm **(#14)**

Where is it in G'MIC?

pirate541 · **Joined:** May 27, 2011 **Posts:** 707

is the script supposed to be saved as a text?
When i saved it,all I get is this:

gimpchat : -skip ${1=32}

-if gimpchat.cimgz
gimpchat.cimgz
-else

# Generate 3d object.
0 -text GIMP,0,0,57,1,255
0 -text[-1] Chat,0,0,57,1,255 -mirror[-1] y
-expand_xy 10,0
-dilate 3
-elevate 64
-permute[-1] zyxc
-r @{-max_whd}
-and
100%,100%,100% -noise[-1] 1 -b[-1] 7 -otsu[-1] 256 -*[-2,-1]
-b 1 -isosurface3d 25%
-f3d 4000 -db3d 0 -m3d 5

# Generate light texture.
256,256,1,3 -plasma[-1] 1,1 -equalize[-1] 256 -n[-1] 0,255
--gaussian[-1] 40%,40%,0 -n[-1] 0,1 -*[-2,-1]
--gaussian[-1] 10%,10%,0 -n[-1] 0,200 -+[-2,-1]
-c[-1] 0,255
-l3d [-1] -rm[-1]
-c3d -n3d -*3d[-1] 250

# Render animation.
-repeat $1
angle={$>*360/$1}
--r3d[0] 1,0,1,$angle

400,400,1,3,-1
-object3d[-1] [-2],50%,50%,0,1 -rm[-2]

-w[-1]

-done
-rm[0]
-a z -autocrop -1 -s z
-to_rgba -replace_color 0,0,-1,-1,-1,255,0,0,0,0
-o gimpchat.cimgz

-endif

-repeat @# -l[$>]
--channels 3 -negative[-1] -b[-1] 2 -shift[-1] 5,5,0,0,1
-rv -compose_alpha
-endl -done

-i[{$1/2}] [{$1/2}]x19
-i[0] [0]x19

so now what do i do with it?

help

YAFU · **Joined:** Nov 09, 2011 **Posts:** 726

Fantastic!
I did not know that technique.

Rod · **Joined:** May 16, 2010 **Posts:** 16152

That is one of the neatest scripts you have written yet David.

Ronounours · **Joined:** Jan 03, 2011 **Posts:** 1656

Note that I wrote this script for a personal use, and didn't put it in the G'MIC plug-in.
But if you are interested, of course, I can rework on it a little bit and put it in the 'Sequences/' folder in the plug-in.

he4rty · **Joined:** Aug 30, 2012 **Posts:** 2174

Thats an amazing effect.

molly · **Joined:** Apr 07, 2010 **Posts:** 14182

pirate541 wrote:

:gaah

is the script supposed to be saved as a text?
When i saved it,all I get is this:

gimpchat : -skip ${1=32}

-if gimpchat.cimgz
gimpchat.cimgz
-else

# Generate 3d object.
0 -text GIMP,0,0,57,1,255

0 -text[-1] Chat,0,0,57,1,255 -mirror[-1] y
-expand_xy 10,0
-dilate 3
-elevate 64
-permute[-1] zyxc
-r @{-max_whd}
-and
100%,100%,100% -noise[-1] 1 -b[-1] 7 -otsu[-1] 256 -*[-2,-1]
-b 1 -isosurface3d 25%
-f3d 4000 -db3d 0 -m3d 5

# Generate light texture.
256,256,1,3 -plasma[-1] 1,1 -equalize[-1] 256 -n[-1] 0,255
--gaussian[-1] 40%,40%,0 -n[-1] 0,1 -*[-2,-1]
--gaussian[-1] 10%,10%,0 -n[-1] 0,200 -+[-2,-1]
-c[-1] 0,255
-l3d [-1] -rm[-1]
-c3d -n3d -*3d[-1] 250

# Render animation.
-repeat $1
angle={$>*360/$1}
--r3d[0] 1,0,1,$angle

400,400,1,3,-1
-object3d[-1] [-2],50%,50%,0,1 -rm[-2]

-w[-1]

-done
-rm[0]
-a z -autocrop -1 -s z
-to_rgba -replace_color 0,0,-1,-1,-1,255,0,0,0,0
-o gimpchat.cimgz

-endif

-repeat @# -l[$>]
--channels 3 -negative[-1] -b[-1] 2 -shift[-1] 5,5,0,0,1
-rv -compose_alpha
-endl -done

-i[{$1/2}] [{$1/2}]x19
-i[0] [0]x19

so now what do i do with it?

help

Pirate, when you save a script you put a .scm extension not .txt.