A+nice+spray+effect?

=A nice spray effect?=

To recreate a spray painting effect and learn the actual motion that is used in spray painting we contacted Mark Chapman who is an experienced spray painter of some years. He was able to shed some light on the way that the gun is used, such as:
 * when the paint should start to flow and when it should be stopped
 * how fast to move the gun accross the surface of the object being painted
 * how far to stand from the surface of the object being sprayed (this turned out to be closer than we expected, which, as you will later read, caused probably our largest problem...)
 * what the paint, or laquer, should look like when applied correctly
 * how much overlap there should be
 * and a number of other small details.

While we were with Mark we took video and still images of the process to refer to later.



The setup of the application to mimic the spray painting was not as difficult as may be expected as we were working on a PC and therefore able to use later versions of the Flash Player. This was very important as we had already found that the spray effect was virtually useless in earlier versions of the Flash Player.

The spray application that was created can be seen, and tried here [] this application will work fine with a mouse. To start 'painting' click on the board and drag, releasing the mouse stops painting. The green button acts as an 'Undo' and removes the paint, while the sliders and colour selection lets you make changes certain facets of the spray effect.

The spray application can mimic different paint types andit may not act like the paint type that you expect. It changes from time to time as we test and may be a laquer or ordinary paint effect at different times.

This application actually used no special programming to get it to work with the WiiMote. The WiiMote was used as a pointer, pretty muct a glorified mouse. In the end that was all we needed it to do. We don't feel that it is necessary to explain the programming techniques needed as this used only Flash Actionscript techniques and had nothing to do with anything specific to WiiFlash Server. Later, we were going to connect some WiiMote functions that would detect rotation of the WiiMote to produce a different paint effect, to do this we would have used the Wii Server applications and scripts as outlined in other pages on this site.

But there were problems...
We had some help from a colleague who actually wired two LEDs into a spray gun in the location where the paint would be sprayed from. The lights were about 3cm apart where the standard distance of a Wii sensor bar is around 20cm.

Our initial test got us quite exited as using the spray gun worked, ie we pressed the button and paint appeared on the screen. Then we started to see that what we needed the spray gun to do was not going to work as the LEDs were too close together.

The LEDs on the sensor bar work similar to this; the closer the LEDs are to each other the closer you can get to the screen though the movements possible are much smaller, for spray painting we may need to move around two metres. The further apart the LEDs are the further from the screen the user needs to be.

The largest problem we had, and what finally made us move away from this spray painting idea was that we could get the range of movement needed, 2 metres, but we needed the LEDs to be about 30cms apart which meant that we needed to stand at least two metres away from the screen, or, in this case the object being painted. This would teach at least one poor practice.

Some more general information about the Wii Sensor Bar.

Next, we could see that one of the ways that our spray painting expert could see the paint was applied correctly was by looking at the reflection of lights in the paint that he had just applied, unfortunately not possible in flash to reflect the real world, and very hard to show a reflection of any kind on the exact right amount of paint in an area deemed to have been sprayed correctly.

When paint is applied too thickly it runs, while there was some ideas about how we could do this it was going to be fiddly and probably not accurate and hard to mimic in different paint types.

We started to reassess our idea, and were thinking about our final case study, was it really valuable to the trainers of spray painting, students that are learning how to paint and the education community at large to only have access to a resource that showed how to //create// a spray application. We refocused on providing more information about how to work with the techniques required to create an application that works with one WiiMote and then 1-4 WiiMotes.

Collaboration on the Wii and a new direction.