Category Archives: macGRID

macGRID is a simulation research network housed at McMaster University’s Sharcnet.

Streaming content from DropBox

Currently (as of 2015) OpenSim’s internal web browser that is used for streaming content does not support HTML5 fully. This is causing effects now with streaming videos from sites like YouTube, and so this guide will provide a simple work-around for playing your videos on the macGRID using self-hosted files with DropBox.

  1. If you do not yet have a DropBox account, make one for free at
  2. Download and install the DropBox application on your computer
  3. Copy the video you would like to stream to the GRID into the DropBox folder that the application created on your computer
  4. Once your file is uploaded, you can right click it and choose “Share DropBox link”, to copy the web link to your file

After these steps, adding media to a prim is the same procedure as before with this new video URL instead of the YouTube URL.

Buying (free) land in the macGRID

Note:- Before you can purchase land, the land must first be sold to your avatar account. All land is initially owned by Mac Grid. Contact Dennian Clarke or Ian Murray for purchasing land.

Follow these steps to get your land:

  1. Skip this step if this is your first time logging into the macGRID. If this is not your first time logging in then start by opening up your viewer and locate your viewer’s Grid Manager and click that. When the Grid Manager is open ensure that the macGRID grid is selected then click “Refresh Grid URLs”. This step is crucial. Because your viewer saves URLs for the macGRID this step deletes any old URLs and replaces them with new URLs that may have been changed for the macGRID. Click “Apply” then “Ok” to exit the Grid Manager.
  2. Log into the macGRID with your avatar account (only the avatar that the land was sold to can complete the land purchase).
  3. Find the map button on your viewer’s screen, I use Singularity so my map is located at the bottom. Now type in your land name into the search box and click “Search”. Use exact names for lands and do not leave out underscores if the land has an underscore in its name.
  4. You can either double click the land on the map or select the land in the list of results and click “Teleport” to teleport there.
  5. After you’ve teleported to the land, from the menu bar above click “Advanced” -> “View Admin Option” or press Ctrl-Alt-V . You will notice an “Admin” menu has now appeared in the menu bar. You must do this so that you can access the “Buy land” option.
  6. Now you have two options to buy the land:
    1. Right-click on the land itself (Buy land option should now be select-able) and select “Buy land”
    2. from the menu bar above click “World” -> “Buy Land”
  7. A dialog box should pop up, it will begin searching for the buy and sell information give it a minute. After it’s completed, agree to the Estate Covenant then click “Purchase”.
  8. The land is now yours.

macGRID: Getting Started

Welcome to macGRID’s Simulation Research Network! Follow these steps to connect to the macGRID.

  1. Download and install the Singularity viewer from the link provided below. You need this in order to connect and view the GRID. Download the package that corresponds to your Operating System. (e.g if you have a Windows click on the Windows Installer).

    1. After the download has completed go to the folder where that downloaded file is located. Open and run the installer. This should take a view minutes.

    2. After Singularity has installed, the program should open itself. If it does not, find the Singularity desktop icon or any other Start Menu Singularity icon and open the Singularity application.
    3. At the bottom of Singularity’s screen you will see a button called “Grid Manager”, click this button.

    4. Now that the Grid Manager is open you can add macGRID to the list on Grids. Begin by clicking “Add” in the Grids tab.
    5. Here you will enter the Grid details in order connect to macGRID.

      Under “Grid name” type in: macGRID

      Under “Login URI” copy and paste this exact URI address into the field:

      Select “Platform” as Opensim (Optional)

      Click “Ok” to apply these settings. Grid Manager will exit. macGRID should now appear in the list of available grids.

    6. Next you need to enter your account details given to. Enter your username in the “Name or Username” field and your password in “Passsword”. Confirm that “macGRID” grid you created in step (6) is the selected grid under “Grid”, if not, click the drop down menu and select “macGRID”. Also, select “My Home” as the Start Location. Click Login.

    7. Welcome to the macGRID! Check other KnowledgeBase articles for more information.

    How do I link objects to create a Linked Building?

    Have the ‘Position’ tool selected in the ‘BUILD’ toolbar.
    Click and drag to create a bounding box – everything that resides ENTIRELY within the box will be selected. By default, selected objects will show a yellow highlight. Ok?

    Click the ‘Object’ tab in your ‘BUILD’ toolbar. Click ‘Link’.

    If all the objects do not have the same owner, OpenSim will not allow the objects to be linked.

    Find the object that is not owned by you (typically a facade, or building element copied from another build).

    Make note of the object’s position and copy it. Click the first “C” to copy its position.

    Make note of the object’s name.

    You will have to ‘take’ this object by right clicking on it and selecting ‘TAKE’

    The object will now be in your inventory. Place it somewhere. 

    Click the second P to position the newly placed object based on the original position (saved on your clipboard).

    Return to step one and select all objects for linking.

    How do I create a building façade?

    1. Create a prim!!
    2. Select the appropriate façade texture that you previously uploaded. This will place the texture on all sides in different orientations. This is what we want.
    3. Use the SELECT TEXTURE option to select the all faces except FRONT and BACK
    4. Make these selected textures ‘ALPHA’
      1. This will help eliminate any ‘edges’ that may be visible on your prim face.
      2. This will ensure that other building textures will show through the ‘ALPHA’ portions of your texture.
    5. Reduce the prim’s z-depth so that it is a single plane. (You should now have a single plane prim with the same texture/facade on both sides)
      1. Ensure that the “Repeats per face” are set to 1.000 for both Horizontal and Vertical.
    6. Adjust the base of the prim using the ‘Stretch’ option in your build tool so that the base matches the edge of a building on your satellite map.
      1. Ensure that “Stretch Texture” is clicked (or you will see multiple building faces appear as repeats).
    7. On the reverse side use the SELECT TEXTURE option, select the ‘FLIP’ checkbox next to ‘HORIZONTAL’
      1. This will create a mirror image (as though your prim was see-through) of your facade front that will aid in moving/adjusting.
      2. Ensure that you use the “Select Texture” option or you will change the texture of both the front and back of your façade.
    8. In the OBJECT tab of our build tool, select PHANTOM
      1. This will ensure that an avatar or other object can pass through any invisible parts of our facade.
      2. By creating a block behind the opaque parts of our facade, we prevent avatars and other objects from going through.

    What’s the best viewer for OpenSim/macGRID?

    In our experience, buildings look much nicer in Singularity. It’s often the case that we’re designing in Singularity, and are unaware of slight differences in Imprudence or other viewers. Make sure we’re using Singularity for demo on high performance mode. (Far draw distance, optimal lighting, etc.)

    Viewing quality is also determined by performance settings on a user’s machine.

    What format should I save images in for upload as textures and facades?

    Textures should be uploaded as PNG files to ensure that ALPHA transparencies are maintained.

    Save images as 24bit color PNG to ensure high-quality edges/transparencies. (As opposed to 8-bit which may cause issues with uneven edgest – OpenSIM will be modifying the image anyway)

    Images are (typically) converted by OpenSIM to have an aspect ratio of 1:1, 1:2,
    Images are converted by OPENSIM to a native file format for use within the grid.
    Images are converted to the following sizes depending on their original resolution/dimensions.

    You’ll typically get image dimensions of:


    However, in cases of extremely uneven aspect ratios for images (such as very wide panoramas), openSIM will may make the width a multiple of the height. (eg, a 512×2048 image).