Initially when you see VVVV, (or V4 which is allot easier to say) you would be forgiven for saying out loud, "What the F**K", is it is not really intuitive at first, but with a bit of time (be prepeared to put the effort in here) it all begins to make beautiful sense.
After doing allot of "playing" and checking out the different patches (In V4 they're called patches, not programs) i decided i wanted to create a patch which would allow me to warp video which would allow me to project a square image onto a curved surface and then correct the image so the would be uniform again. Just in case you didn't know, when you project onto any surface which isn't flat such as a column, the image becomes warped due to the fact that the further the projected light has to travel before hitting the projection surface the larger area it will cover. This means that if you were to project onto a column the part of the image closer to the projector (the middle) would appear "pinched" and the outside of the image would appear splayed. By stretching and squeezing the image at certain pints you can "re-correct" this deformation so you get a nice even image wrapped around one half of a column.
Below is a few screen shots of the patch i used, this is a very early version, the new one includes multiple video switching and some nice keyboard shortcuts which would be handy if you were using this in a live situation.
This is a shot of the basic patch with the inspector and a render (the preview monitor open)
Above is an example of a warped video for projecting onto a vertically linear concave surface, by pinching the center of the image, when it is projected onto a curved surface where the center is a longer distance from the projector than the outsides, the center of the image will be "stretched" due to the distance, creating a uniform image.
Here is a rough example of how you would warp an image if you were projecting directly onto a corner surface such as a four sided pillar, this would create two uniform squares on two sides of the pillar using only one projector.
Once I get some photos of this in action i will post some corresponding examples of this technique in action. Currently i am working on a new type of protocol for mapping, video/images to a custom built LED wall. If you use V4 and would like to chat please get in contact.
If you enjoyed this post please feel free to buy me a gingerbread late! mmmm!
Tags:
hi,my compliment for your job, i'm absolute beginner whit vvvv can you help me to understanding the vvvv way to manipulate image? actually i'm working on lighting desk but i cant do what you are doing,but suppose whit lighting desk the way to programming light's it's faster then vvvv.there is a way to give input from my desk to vvvv? i can use outpout protocol: dmx - artnet
max
Hi Max, I'm glad you enjoyed the post. The best way I have found to learn vvvv is to look through the "Girlpoer" folder which comes with vvvv and see how those patches do what they do. Also if you select a node and hit the "F1" key, it wil bring up an example of how to use that node. Your probably better using a conventional lighting desk to program most lighting fixtures but you can also send DMX commands to vvvv, via a DMX interface (Checkout Enttec) and use this to trigger video or specialist "bespoke" lighting fixtures.
Have fun!
Andy
Hi
Nice/ try to see your patch but no success…
So you create points on the grid and then edit them for warping images… / something like this? (grid editor)
I must project videos next week on concave surfaces that's why i'm intersesting.
Tim
HI Tim, take a look at the GridEditor (EX9) help patch in the modules folder as a starting point, it is quite easly to apply a video texture to the mes and adjust the points and camera angle accordingly. Be aware that when focusing on a concave surface some parts of the image will be slightly out of focus dpending on the depth of the screen. Let me know how you get on.
Andy
Hi andy, i try the Grid editor patch, so for apply a texture = no problem but then i don't have a single point so i can't edit.
I try other patch with the module "point editor", for example deform 3D mesh and it just work fine (i can add points by increasing the resolution of the grid and move them after).
I pass something like 3 hours, trying to have points with grid editor and no sucess / maybe i miss something ?
A solution ?
Tim
Hi Tim, email me direct with what youve got and ill see if i can help. One thing to try is to create another renderer (a second one) i have known points appear on one renderer but not the other?!
Andy
You're fucking right (don't know why the two renderer have exactly the same properties) anyway Big thanks for taking the time to answer my questions…
Tim
No it was the "window dephth buffer format" of the original renderer who was set to "D16" if you put nothing "none" then the points appears.
Thanks
Nice one, let me know how you get on, vvvv is so versatile and has soo.. many settings you nearly always get there in the end!
Andy