Two-part manipulation: Spatial Mapping & 3D

As I have already written two proposals on this artwork, I am simply going to continue to update at this point.  My accomplishment from last week, involving texturing a cylinder will go to use in adapting the video so that it projects undistorted.  However, I find that I cannot use this same method for manipulating the video to account for the viewer's perception of the projection, due to the fact that 3D objects are rendered directly to the video card.  As they are written directly to the video card, there is no matrix output for them, and therefore, I cannot manipulate an image after sending it to the renderer.  So, I must change the video to account for the viewer's perception FIRST, which I have been working on using spatial mapping (as in jitter tutorial 39) and then set that matrix as a texture for the cylinder. 

Maintaining the illusion

At the moment, I am debating whether to require viewers to wear a specific hat in order to track the angle at which their head is turned, which would dictate how the video is manipulated in order to appear straight on to the viewer.  This would provide a more immersive experience, as the illusion would not be broken by a simple turn of the head.  However, it does break the naturalness of the viewer’s interaction with the environment by forcing viewers to wear something they normally wouldn’t.  I have yet to make a decision on which loss is more substantial, and I think, now that my calculations have become more defined, that it will not be a big difference in effort to change the program to account for the angle of the viewer’s head.  Therefore, it is probably best to leave the decision to later, after I have tried the simpler version that doesn’t account for it.  Only by walking through myself do I feel I can make the most informed decision.

 (Yet, I’d be interested in what other people think about which would be more satisfying and would best maintain the illusion, so comments are appreciated.)

Project 1: a short proposal

Altering video for projection on curved surfaces

Having recently done an installation using projectors for my video class, it came to my attention now that I will need to alter the equation I have written down in my notes regarding alteration of video for projection.  The previous equation took into account the way a curved image would appear to a viewer, but did not take into account the way in which light bends.  Unlike the way an image appears on curves, projection size distortion is NOT related to angle specifically, but IS related to proximity directly.  Things become more complicated now and I feel I've barely scratched the surface of the project's application.  I will need to experiment with a projector in order to understand the way the light will bend.

location and structural dilemmas

As I am planning to create a large curved corridor through which viewers will walk, I was presented with the dilemma of creating some sort of curved frame from which to hang the curtains/screen.  But I may have found a solution to the problem that does not include creating a frame at all.  If I can gain permission to use the rotunda of Shafer, I can use the pre-existing curve on the ceiling in order to hang the "screen."  The walls are not perfectly flat, so unfortunately, I cannot hang the "screen" against them.  But the ceiling, interestingly, has a curved ledge.  In terms of my project, I see two functions for this ledge: 1) as a place to install the projectors; and 2) as a place from which to hang the "screen."  Unfortunately, I cannot do this with the same efficiency as a child builds a fort from blankets, simply placing heavy objects on top of the sheet's end to hold it in place.  This would be insecure and dangerous.  So my new dilemma is to find a way to attach the "screen" to that ledge without causing damage to the ceiling (or the viewers!).