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Viewing 15 posts - 301 through 315 (of 483 total)
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  • in reply to: Min system specs? (not models) #101699

    Oliver Kreylos
    Keymaster

    “CPU% on the other hand is not so pretty, it’s in the %175-195% for SARndbox process alone (over 100% because split across two CPU cores I presume).”

    In your case CPU appears to be the bottleneck. I used to run exclusively on AMD in the past, and nothing could touch the Athlon in its day, but it doesn’t hold a candle to Intel’s newer Core CPUs. Your CPU simply can’t feed the graphics card fast enough to push the latter to 100% utilization (and yes, it’s more than 100% CPU as the AR Sandbox code is multi-threaded). The moment your CPU jumps over the minimum spec hurdle, the bottleneck is going to be, and then stay, the GPU.

    in reply to: Rain setup (options) #101693

    Oliver Kreylos
    Keymaster

    Yes, I realize what’s going on. Try running the SARndbox without the -fpv command line parameter. You’ll notice that the projected sand surface doesn’t line up with the real sand surface at all. That’s because without -fpv the sandbox doesn’t use the calibration matrix that you created.

    However, when running SARndbox with -fpv, while the calibration matrix is applied to the display, it is not applied to the software’s internal representation. Meaning, when you think you’re clicking on some part of the map, the software thinks you clicked on something entirely different. Fixed projector view, via -fpv, and mouse-based interaction were never meant to be used together.

    You can work around the problem by running the sandbox without -fpv, and using standard mouse-based navigation to manually line up the projected and real sand surfaces as closely as you can (you will not be able to get a perfect alignment). Then save the current viewing state via “Save View…” in Vrui’s system menu, and the next time you start SARndbox with -fpv, load the view you previously saved, either via the main menu, or the -loadView <view file name> command line option. After that, mouse interaction should be closely aligned.

    in reply to: Intrinsic Calibration Mean #101686

    Oliver Kreylos
    Keymaster

    Intrinsic calibration defines how a depth camera such as the Kinect converts from two-dimensional depth images to three-dimensional geometry. Without intrinsic calibration, the surfaces reconstructed by depth cameras would not be a 1:1 match to their real counterparts. While each Kinect is individually calibrated at the factory, and contains the resulting calibration data in its firmware, the calibration is not particularly good. Most importantly, a factory-calibrated Kinect will reconstruct a flat plane as a gently curved bowl. In the AR Sandbox, this would lead to elevation contour lines that are not completely flat when viewed from the side, or water that might appear to flow uphill.

    The custom intrinsic calibration procedure in the Kinect package is rather complex, but it can correct for almost all of these problems.

    In technical terms, the result of intrinsic calibration is a 4×4 homogeneous projection matrix that transforms depth-valued depth image pixels (px, py, d, 1) into 3D positions (wx, wy, wz, w). (These 4-vectors are homogeneous points; to convert them to regular affine points, the first three components are divided by the fourth, which is then dropped. So the affine counterparts of the two given vectors would be (px, py, d) and (x, y, z), respectively.)

    The depth conversion formula is a part of the intrinsic 4×4 matrix that describes how a depth value d as reported by the Kinect is converted into a metric distance z in centimeters. Concretely, the conversion is z = A / (B – d), where A and B are device-dependent constants determined during calibration. A is usually around 32000, and B is around 1090.

    in reply to: How to enable / use rain function? #101683

    Oliver Kreylos
    Keymaster

    Water simulation / rain is turned on by default, but you might have to configure the elevation range at which the software detects “rain clouds,” especially if you use a non-standard base plane elevation.

    To test the water simulation, create a water tool: When the sandbox software is running, press and hold the “1” key, move the mouse to highlight “Manage Water Locally” from the tool selection menu, and release “1” to select. Then press and release “2” to assign the secondary function. Afterwards, press and hold “1” to let it rain underneath the mouse cursor.

    (You can use any keys or buttons you want instead of “1” and “2”.)

    To make it rain from your hands, you need to move your hands into the rain elevation range and hold still. By default, the rain range starts a few centimeters above the highest terrain elevation configured in your color map. You can configure the rain elevation range directly via the -rer <min elevation> <max elevation> command line parameter, where <min elevation> and <max elevation> are elevations relative to the base plane configured in BoxLayout.txt, in centimeters.

    in reply to: Version of Kinect #101682

    Oliver Kreylos
    Keymaster

    From the instructions page:

    The AR Sandbox software, or rather the underlying Kinect 3D Video Package as of version 2.8, supports all three models of the first-generation Kinect (Kinect-for-Xbox 1414 and 1473 and Kinect for Windows). All three are functionally identical, so get the cheapest model you can find. Note: The second-generation Kinect (Kinect for Xbox One or Kinect for Windows v2) is not yet supported by the AR Sandbox software.


    Oliver Kreylos
    Keymaster

    Yes, those components will work, but consider that you’re going to be paying almost USD 3,000 more, compared to a Core i7/GeForce combination, for no significant performance improvement.

    in reply to: Rain setup (options) #101676

    Oliver Kreylos
    Keymaster

    Works in all of them.

    in reply to: Rain setup (options) #101669

    Oliver Kreylos
    Keymaster
    1. Press and hold “1” and select “Manage Water Locally” tool.
    2. Let go of “1” to assign “rain” function.
    3. Press and relase “2” to assign “dry” function.

    Then, press “1” to rain, or “2” to dry locally.

    in reply to: Complete Installation Instructions #101667

    Oliver Kreylos
    Keymaster

    I just built the whole thing using both g++ 4.7.2 and g++ 4.9.2, and both worked without flaw.

    Did you by any chance accidentally build against Vrui-3.1-003? Run $ ~/Vrui-3.1/bin/AlignTrackingMarkers -vruiVerbose to see the exact Vrui version you installed.

    in reply to: Complete Installation Instructions #101665

    Oliver Kreylos
    Keymaster

    What operating system and version of g++ ($g++ -dumpversion) is this?

    in reply to: Cleaning the sand? #101655

    Oliver Kreylos
    Keymaster

    If you have dust, you should definitely try washing your sand. Sand dust might muck up the workings of your PC and projector, and if your sand is silica/quartz, i.e., the kind of stuff you find at the beach, then you don’t want to breathe in large amounts, either.

    Sandtastik sand, the brand we recommend, has a cleaning guide that might or might not work for you.

    An alternative idea, off the top of my head, would be to dump a bunch of sand into a bucket, fill the bucket with water, and then use a plastic mesh kitchen strainer to fish handfuls of sand back out of the bucket, shaking on the way out to get rid of fine dust. If your sand is finer than the finest strainer you can find, you could try using a cheese cloth, but I’m just spitballing at this point.

    in reply to: Full Screen Mode #101645

    Oliver Kreylos
    Keymaster

    As of Vrui-3.1-004, all Vrui applications enter/leave full-screen mode via Win+f. Window system-wide keyboard shortcuts still work as well, of course.

    in reply to: Full Screen Mode #101642

    Oliver Kreylos
    Keymaster

    Creating a text file via terminal:

    $ pluma <name of file>

    pluma is Mate’s text editor, and <name of file> is the file name, with optional path. E.g.,

    $ pluma Vrui.cfg

    to create Vrui.cfg in the current directory, or

    $ pluma ~/Vrui-3.1/etc/FullScreen.cfg

    to create FullScreen.cfg inside Vrui’s default configuration directory.

    If you quickly want to create a short file with only a few lines, you can use cat:

    $ cat > <name of file>

    The first “>” tells cat to write into the given file. Then just type one or more lines into the terminal, and press Ctrl+d to finish the file.

    To display the contents of a (short) text file, use cat without the “>”, e.g.,

    $ cat ~/Vrui-3.1/etc/FullScreen.cfg

    To browse through longer files inside a terminal, use less instead of cat. Of course, you can always use pluma to look at files, but you run the danger of accidentally modifying the file.

    in reply to: Full Screen Mode #101630

    Oliver Kreylos
    Keymaster

    Add -vruiVerbose to SARNdbox’s command line. This will tell you which configuration files Vrui is trying to load on start-up. Make sure the one you made is among them.

    Don’t worry about icons, but ensure that the name of the file is exactly the same as the one you specify after -mergeConfig. Do an $ ls on the directory where you saved the file, and check that everything matches. If there are spaces or other special characters in the file name, you need to enclose it in double quotes when giving it on the command line.

    in reply to: Model Export #101629

    Oliver Kreylos
    Keymaster

    That shouldn’t happen, and I don’t know what could be causing it. Try capturing a longer video sequence, and experiment with different frame indices, and see if it makes a difference. Use a frame index range, say 60 100, to check if you get at least a few frames, and look at my comment above regarding the output file name format (it needs to include a number conversion).

Viewing 15 posts - 301 through 315 (of 483 total)