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Viewing 15 posts - 301 through 315 (of 498 total)
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  • in reply to: Dynamically adjust the contour datum ? #101819
    Oliver Kreylos
    Keymaster

    There is currently no code to change the contour line offset in the code. There is the ability to change color maps on-the-fly that maphew pointed out.

    That feature might work better for your purpose, but will require some work. To show the effects of water level changes, you could create a series of color maps that are identical in the high-elevation parts, but cut from dry land color to blue at different elevations (and the granularity of those changes is entirely up to you). By dynamically switching between those, you can raise or lower the apparent water level. The nice thing is that the changes won’t affect dry parts of the surface at all, so it will look much nicer. If you offset contour lines, or change the base elevation plane, everything will change, which might bury the changes you want to show.

    Changing the base plane would be a pretty simple feature to put in, though.

    in reply to: Per-pixel depth correction #101815
    Oliver Kreylos
    Keymaster

    The Kinect v1 has a set minimum scanning distance, and when you’re getting close to that distance, you will see points appearing or disappearing randomly, due to measurement errors. But once you move more than a few centimeters below the minimum distance, you should get a solid black depth image.

    in reply to: Rain bounding box #101814
    Oliver Kreylos
    Keymaster

    The water simulation’s bounding box is set when you measure the 3D corner positions of your sandbox during calibration. You can either re-do that step and put your new values into BoxLayout.txt, or move the corner points outwards manually by editing BoxLayout.txt. Don’t overdo it though; if the simulation bounding box extends beyond the edges of your sand surface as captured by the Kinect, you will get drastically reduced simulation performance.

    in reply to: BoxLayout File #101790
    Oliver Kreylos
    Keymaster

    BoxLayout.txt already exists, in /etc/SARndbox-<version> inside the SARndbox source code directory. You can edit that file, or copy your new file into that directory.

    in reply to: Calibration Problem! #101779
    Oliver Kreylos
    Keymaster

    When you create the “Capture” tool, you assign two buttons to it — the first one you press to bring up the tool selection menu, the second one you press when the tool creation dialog box pops up.

    To capture a tie point, press the first button you assigned, not the second one.

    in reply to: Complete Installation Instructions #101769
    Oliver Kreylos
    Keymaster

    Did you cd into the SARndbox directory before trying to run ./bin/CalibrateProjector? It should go like this:

    $ cd ~/src/SARndbox-1.6
    $ ./bin/CalibrateProjector -s 1024 768

    If that still doesn’t work, do

    $ ls ~/src/SARndbox-1.6

    and check that the d, o, and bin directories exist. If not, run

    $ make

    If you run into further problems, please start a new thread in the main forum. This thread is becoming hard to manage.

    in reply to: Complete Installation Instructions #101764
    Oliver Kreylos
    Keymaster

    The Kinect software works fine over USB 3.0, but the problem is that some USB 3.0 host controllers are poorly supported in the Linux kernel itself. Basically, there are a lot of broken USB 3.0 controllers on the market that require “quirks” to make them work, and those are only implemented in secret custom drivers, typically only for Windows. Unfortunately, your laptop might have one of those USB chips.

    You can find out which controller chip you have via lspci | grep "USB 3.0". The ones known to be good are by NEC or Renesas, chip ID uPD720200 or similar.

    in reply to: Complete Installation Instructions #101763
    Oliver Kreylos
    Keymaster

    That appears to be a configuration problem. SARndbox is looking for the projector calibration matrix in the wrong place. You can test this by copying ProjectorMatrix.dat from /home/matt/src/SARndbox-1.6/etc/SARndbox-1.6/ProjectorMatrix.dat (where it should be) to /home/matt/src/SARndbox-1.6/ProjectorMatrix.dat (where SARndbox seems to be looking for it).

    But it shouldn’t be looking there. Somehow your SARndbox source package seems to have gotten messed up. It’s probably best to back up your configuration files (BoxLayout.txt, ProjectorMatrix.dat), remove the entire SARndbox-1.6 directory, and download a fresh tarball. Then copy the config files back where they really belong, and you should be good.

    The Pi2 is going to be marginal for running an AR Sandbox even without water, but this problem has nothing to do with the Pi.

    in reply to: Complete Installation Instructions #101762
    Oliver Kreylos
    Keymaster

    for me sudo apt-get install libdpkg-perl was the key.

    Thank you for figuring that out, and reporting back. I can add that package to the list in the Build-Ubuntu.sh script.

    in reply to: BenQ MX631S projection angle to sandbox #101761
    Oliver Kreylos
    Keymaster

    The 105% figure means that, if your projected image is 1m tall, its bottom edge will be 5cm (5% of 1m) above the imaginary center line of the projector.

    The projector lens is designed such that the image will be in focus everywhere if projected onto a flat screen that is at a right angle to that imaginary center line. Concretely, if you put the projector completely level onto a table and project onto a vertical wall, the image will sit 5% above the horizontal plane going through the lens center, and the entire image will be in focus.

    The downside of above-centerline projection for AR Sandboxes is that the light at the front edge of the sandbox, where most users will stand, comes in at a fairly low angle, which reduces brightness, and can lead to shadowing when there are steep slopes facing away from the projector. A centerline projector directly above the sandbox’s center point would improve that.

    The ECHO, TERC, and LHS setups use a compromise where the projector is shifted towards the center of the box, and tilted out to move the projection image back to the center. This was necessary because the projector hood was designed too small.

    There are two problems when a projection surface is not orthogonal to the projector’s centerline: keystone distortion and focus. Keystone distortion is effectively taken care of by the AR Sandbox’s calibration procedure, but focus remains. With a tilted projector, only a single horizontal line is in perfect focus; lines above and below that become increasingly blurry. It’s not a huge effect, but it is noticeable. Enough that I don’t recommend building an AR Sandbox with a tilted projector.

    in reply to: Complete Installation Instructions #101733
    Oliver Kreylos
    Keymaster

    Which Linux distribution and which exact version are you using?

    in reply to: Version of Kinect #101730
    Oliver Kreylos
    Keymaster

    As good a place to start as any: The Kinect 2.0.

    in reply to: Version of Kinect #101728
    Oliver Kreylos
    Keymaster

    The first-generation Kinect has a nominal depth map resolution of 640×480 pixels. Its effective resolution is much lower as only a fraction of pixels carry depth measurements at any given moment, due to the way the structured light scanning technology works. The second-generation Kinect has a depth map resolution of 512×424 pixels, but it carries depth measurements on every pixel, based on its time-of-flight scanning technology.

    In short, the AR Sandbox’s recommended display resolution of 1024×768 is higher than that of any available depth camera, and also higher than water simulation grid sizes supported by current graphics cards. You can run the AR Sandbox at higher display resolution, but you won’t get more detail in the terrain model or water behavior. The only difference are narrower contour lines.

    in reply to: range of color in Rawinectviewer #101713
    Oliver Kreylos
    Keymaster

    You can change the depth range by passing a -depthRange <min depth> <max depth> parameter on RawKinectViewer’s command line. Depth values are not metric distances, however. You should try -depthRange 900 1090 first and see how that works out.

    Alternatively, you can define a base plane interactively, and color everything by distance to that base plane. Flatten the sand surface, and select “Average Frames” from the main menu. Then assign a “Define Depth Planes” tool to two arbitrary buttons say “1” and “2”. Then press “1” a few times to select points from your sand surface, and press “2” once to define a plane approximating all those points. Afterwards, the edges of the box should show up clearly. You can then assign the 3D measurement tool and measure points as usual.

    in reply to: Calibration "CD" always yellow except outer edge. HELP!! #101712
    Oliver Kreylos
    Keymaster

    When you measured the corner points of the AR sandbox, did you measure in counter-clockwise order, or in correct order lower left, lower right, upper left, upper right? If the former, you need to swap the last two lines in BoxLayout.txt.

Viewing 15 posts - 301 through 315 (of 498 total)