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  • in reply to: Support the AR Sandbox #116019

    Oliver Kreylos
    Keymaster

    You can mount camera and projector at different heights, but the higher you go, the less mechanically stable it will be. You can also use a mirror to fold the projector’s light path. For example, if you had a 2.0 throw ratio projector, you could place the projector at the same level as the sandbox, and put a mirror at the same level as the Kinect. There are some examples of AR Sandboxes with mirrors on my “External Installations” page.

    There is no graphics card that works perfectly; the AR Sandbox’s water simulation can bring pretty much anything to its knees under some circumstances due to its conservative (meaning, conserving physical quantities) nature. But an Nvidia GeForce 1050 works well enough that when it does stutter once in a while, you can bring it back by removing some water from the simulation. You could also use older GeForces such as GTX 960, 770, or 680, but you will get more stutter the further down you go.


    Oliver Kreylos
    Keymaster

    That is correct; the projector calibration matrix overrides Vrui’s navigation and viewing transformation in -fpv mode. As the calibration matrix is an arbitrary projective transformation, to support all possible alignments between projector and camera including keystone distortion, it can not be fully recreated by Vrui’s transformations, which are uniformly scaled rigid body transformations. The best option is to align those two transformations as closely as possible, in which case interaction with UI components such as virtual input devices will work quite well.

    Start SARndbox without -fpv, and use the normal mouse navigation tool to align the 3D model as best as you can with the 3D sand surface by rotating, panning, and scaling. Then save the current viewpoint (Vrui system menu, view, save view), and afterwards start SARndbox with -fpv -loadView <viewpoint file name> That will load the manually-aligned view, and now Vrui objects including virtual input devices will be rendered almost in the correct places.

    in reply to: Slow water??? #115992

    Oliver Kreylos
    Keymaster

    What’s your graphics card’s load while water is slow? Run nvidia-settings and go to the “GPU 0” tab, which will show GPU utilization in percent.

    In general, water simulation speed is mostly independent of the amount of water in the box, but directly dependent on the maximum velocity of any water in the box. If you have any very steep terrain, or, even worse, spikes or holes from Kinect 3D reconstruction artifacts, the simulation will run slow if there is any water around those problem spots.

    Are you running a Kinect v1 or v2?

    in reply to: Screen and Water alignment off #115991

    Oliver Kreylos
    Keymaster

    The boundaries of the water simulation are read from BoxLayout.txt. Re-do the installation step where you measure the base plane equation and box extents. Afterwards, re-do the projector calibration step.

    in reply to: Unexpected screen after software installation #115990

    Oliver Kreylos
    Keymaster

    There are sometimes issues when starting a new color stream on the Kinect v2, resulting in warnings from the JPEG library. But those normally don’t affect operation, and are independent of the depth stream.

    in reply to: Two images in RawKinectViewer are different #115989

    Oliver Kreylos
    Keymaster

    In the first-generation Kinect, both the depth and color stream are 640×480 pixels. In the second-generation Kinect, the depth stream is 512×424, and the color stream is 1920×1080. Hence the different image sizes. In addition, the second-generation Kinect has lens distortion correction coefficients for the depth camera, which is why the depth image is not rectangular.

    Regarding the second problem: /etc/… is a strange location for the AR Sandbox configuration files. They’re usually in /home/<username>src/SARndbox-2.4/etc/SARndbox-2.4 unless you changed the makefile. Check that the files have correct permission.

    in reply to: Feature wish list #115988

    Oliver Kreylos
    Keymaster

    There isn’t a direct feature for continuous local rain in the AR Sandbox code. However, there’s a Vrui way to simulate it. The local rain tool, like all other tools, is bound to an input device, such as the mouse. Vrui lets the user create an arbitrary number of virtual input devices dynamically, and then bind tools to them as to any other device.

    Basic steps:

    1. Create a new virtual input device with two buttons by selecting “Vrui System” -> “Devices” -> “Create Two-Button Device” from the main menu. This creates a grey wireframe box with two small cubes above it and one small cube below in the middle of the screen.

    2. Bind a tool to control virtual input devices to the mouse. Press an unused mouse button or key, and select “User Interface” -> “Input Device Driver” -> “Ray-Based Driver” from the tool menu. Press the same button or key again to confirm.

    3. Now you can pick up and move the grey wireframe box by pointing at it with the mouse and holding the button/key to which you assigned the ray-based driver tool. You can toggle the virtual device’s button by selecting either of the two cubes above the box with the same button/key. A “pressed” button turns green. The first time you press a button, the tool selection menu pops up. Now move the virtual device to highlight “Manage Water Locally,” then toggle the virtual button off. Toggle the other virtual button on and off to assign the “drain” function.

    4. Now move the virtual device anywhere over the terrain, and toggle on its first button. It will start raining until you toggle the button off again.

    in reply to: USB Button Solution #115986

    Oliver Kreylos
    Keymaster

    Are there error messages when starting SARndbox? Check that your modified configuration file is loaded by adding -vruiVerbose to the command line.

    in reply to: looking for a replecment cheap sand #115985

    Oliver Kreylos
    Keymaster

    The sand should be light and of a neutral color, i.e., light gray or white, to achieve a bright projection with high contrast. Other than that, there are no technical requirements. Other light-colored granular materials, for example paper pulp, work as well.

    From a health perspective, inhaling quartz dust is a health risk. The recommended Sandtastik sand is feldspar, not quartz.

    in reply to: Will Updating OS Affect Software? #115944

    Oliver Kreylos
    Keymaster

    Do you use your sandbox computer for anything other than the sandbox? If not, I’d recommend not upgrading the OS. Treat it like an appliance.

    That said, an upgrade between major OS versions might require a re-installation of the Vrui, Kinect, and SARndbox packages as some system libraries might change to incompatible versions. I recommend rebuilding all three packages after the upgrade to be safe. Back up your main Vrui.cfg (if changed), your Kinect’s calibration data, your SARndbox’s BoxLayout.txt and ProjectorMatrix.dat, and any custom shaders or scripts you installed.

    in reply to: Problem with OpenGL #115941

    Oliver Kreylos
    Keymaster

    No, if your graphics card and/or drivers do not support water simulation, you cannot use water simulation.

    in reply to: Problem with OpenGL #115889

    Oliver Kreylos
    Keymaster

    Actually, don’t downgrade the Kinect package.

    Instead, upgrade to version 3.6 of the Kinect package, which checks if GL_EXT_gpu_shader4 is supported by the local OpenGL and, if not, falls back to a facade projector that does not use it.

    Download and install Kinect-3.6 per step 4 of the installation instructions, and then re-build your SARndbox package:

    cd ~/src/SARndbox-2.5
    make clean
    make

    Then run CalibrateProjector again. You still won’t get water simulation, though.

    • This reply was modified 6 months, 4 weeks ago by  Oliver Kreylos. Reason: Oops, bad instructions
    • This reply was modified 6 months, 4 weeks ago by  Oliver Kreylos. Reason: New Kinect package version
    in reply to: Unexpected screen after software installation #115888

    Oliver Kreylos
    Keymaster

    The Kinect-for-Xbox-One is a primadonna, which is one reason why we don’t recommend using it. The two I have work reliably with Kinect-3.4 and Kinect-3.5, but I have not tried any others myself.

    Do you get any error or warning messages when starting RawKinectViewer, such as buffer under-/overflows or USB stalls? If that, try using different USB ports.

    in reply to: Corner order in calibration step 5 #115887

    Oliver Kreylos
    Keymaster

    It appears you are following obsolete instructions. Please follow these step-by-step installation instructions.

    in reply to: I get error in step 11. #115886

    Oliver Kreylos
    Keymaster

    Please check the spelling of the commands you enter, including uppercase/lowercase. The correct command is:

    ./bin/CalibrateProjector -s 1280 800

Viewing 15 posts - 31 through 45 (of 453 total)