camera control with wii nunchuck

hey everyone,

I want to control a rhino-view-camera by the movement of a wii-nunchuck. I get the values from the wii over an arduino (all buttons, accelerators and joystick) and want to use them now for camera movement.

the first problem is that I can only move an object relative to the values I get (means that when there are values from -1 to 1 this would be the whole range of movement). what I want to do is to add all values steady so that I can have an absolute movement of my object.

second problem is that there are no camera objects in grasshopper yet. is there a possibility to do it with .net?

thank you

Replies to This Discussion

Permalink Reply by Luis Fraguada on February 23, 2010 at 4:16am

the value issue is not a big one, just modify to the range you need...yes, it is possible to move 'cameras' within a .net component...google search the vb & c# area for some examples...

Permalink Reply by dominik nuessen on February 23, 2010 at 6:29am

hey Luis,

thank you for your quick reply. I think the problem of the range is more complex. the grasshopper definition updates the wii-values each 50 ms, so I get a single integer value each time. imagine you want to move the camera for 5 seconds straight forward - then you have to add all incoming values and that every 50 ms. so your movement becomes absolute and is not limited to a definded range.
because of that I need a variable that is growing or at least changing every time the definition gets updated, a resulting value consisting of all values that came in since the definition was started.
any ideas?

Permalink Reply by kleerkoat on February 23, 2010 at 6:54am

this sounds interesting!

Permalink Reply by Damien Alomar on February 23, 2010 at 7:42am

For camera movement, take a look at the post on my blog entitled "How to Make a Line go Crazy". The definition that was used for that animation does pretty much about all you'd want for camera movement (camera and target locations, focal length, camera roll). The definition is available for download at the end of the post

Permalink Reply by dominik nuessen on February 23, 2010 at 10:44am

thank you damien, I will have a look at your definition... by the way, nice blog!

Permalink Reply by dominik nuessen on February 23, 2010 at 11:43am

damien,
I tested your definition, really nice work! it seems that camera controlling is not that difficult in .net (if you are not a total newbie like me). in your definition you flow along defined paths to evaluate the camera position and target. in my case it would be no problem to feed your .net component with calculated points, right?
what I want to say is that I just need to translate the wii-movements into point coordinates and put them into your .net component.
...thank you, now I am one step closer...

Permalink Reply by Damien Alomar on February 23, 2010 at 12:02pm

Yea, its not that hard if you know where to look ;) Also, using the active viewport makes it fairly easy as well.

I really can't say exactly what you need because I'm not really certain how your data is coming in. Camera location is going to need a point. The target location/camera direction as well as the camera Z need to be expressed as a vector. I think in my component I just created the vector for the camera direction on the fly from the camera location and the target location.

Permalink Reply by dominik nuessen on February 23, 2010 at 2:16pm

my data consists of a string like this: 123,200,30,0,0,100,214
the first three values are the x,y and z accelerators of the wii, the 0,0 are the two buttons and the last two numbers are the joystick axis. I took the definition and the library from andrew payne from liftarchitects (http://www.liftarchitects.com/) and adjusted it to my needs. he wrote a vb-listener, that reads the values from the wii connected by an arduino and feeds it into grasshopper, every 50 milliseconds. what he did now is to split the string in several single strings, that I again turned in values between -1 and 1.
what I need now is a method to add all the incoming values for each movement of the wii in grasshopper for getting an absolute camera movement. but as I am not able to create a grasshopper-component that adds the latest value to the former ones - every 50 ms I don´t know how to proceed.
any idea?

Permalink Reply by FrankS on February 23, 2010 at 2:20pm

As you said, you will need to to sum up/add/accumulate all x,y and z values from the wii separately. this means adding deltas (relative changes) to absolute coordinates. you can use "compose point" to generate points from the xyz values.

i am not sure how to accumulate values and i am not in front of gh right now. maybe there is a function Inside the fx component...

Permalink Reply by FrankS on February 23, 2010 at 2:43pm

hi Core. Oops. i replied before reading your answer. i remember an accum(ulate) function from max/jitter. did you check the "Display function List" Button in fx editor.

Permalink Reply by dominik nuessen on February 23, 2010 at 3:50pm

damien, your .net component is working fine. I simulated my wii-movements with grasshopper sliders and it works great. thank you for that!

frankS, thanks for your suggestion. I will try it now! I wonder if I have to connect the 50 ms component to whatever accumulation component...?

Permalink Reply by taz on February 23, 2010 at 5:18pm