Need to draw into FBO for Kinect-projector calibration to be applied properly

[mattfelsen]

Hello! I got around to playing with Rulr over the weekend and was able to get the calibration working properly without much issue. Awesome! Everything looked good when using the NodeThroughView to test the alignment.

When I used ofxRay::Camera::beginAsCamera() to apply the calibration matrices, I had a weird, large horizontal offset. After drawing into an FBO first, however, and then drawing that to screen, everything was good to go. Perhaps ofFbo::begin() is doing something with the viewport to make it work? I was testing on 0.9.x -- I think 0.9.3.

[elliotwoods]

you can download full Rulr build environments from
https://drive.google.com/drive/folders/0B_S1z3_AWMRSflJGdkhTZ3Qta2hUZF9MTHU4NXRQWUl3Vnc2YVZoNU8wZ1ktVHk4VEFvUFk?usp=sharing

it seems the last upload is september 5th

this 'sdk' comes with oF, ofxRulr, all the required addons

i've been doing a lot of work recently with beginAsCamera to implement BAM maps in Rulr
https://www.youtube.com/watch?v=s2zGoujapog
https://github.com/elliotwoods/ofxRulr/tree/master/Plugin_BrightnessAssignmentMap
which worked well for me, but yes, that was all into ofFbo (which actually comes out upside-down)

sounds very strange, not something i've come across.
really curious where the issue comes from but don't have time to look into it
things that might be different inside the fbo:

• getWidth/getHeight functions
• different screen setup function in advance (although i thought i clear all that)
• different viewport settings

to be honest, i'm just fascinated that anybody has been able to get rulr compiling..

elliot

[mattfelsen]

Hey, thanks for getting back so quickly.

The answer about compiling Rulr is simpler than you think: I didn't. I used the 0.5 20161031 release :) And I watched through various videos in the hackpad to understand the Kinect-Projector calibration procedure (sorry, I didn't actually specify what I was calibrating in the original post).

Indeed, things did come out flipped, but passing flipY = true into beginAsCamera() takes care of that. I agree it's probably a size/viewport mismatch, but no need to worry about it now as drawing into an FBO seems to fix it. I just wanted to post in case anyone else runs into the issue 👌