MapInfo Pro

Expand all | Collapse all

MapInfo Monday: Fast Symbol Rendering

  • 1.  MapInfo Monday: Fast Symbol Rendering

    Posted 02-01-2021 08:51
    Edited by Peter Horsbøll Møller 02-02-2021 02:08
    Happy #MapInfoMonday!

    Today, we will look at a preference that will speed up the rendering of point data in your maps: Fast Symbol Rendering. We will also discuss when this preference should not be used.

    What is Fast Symbol Rendering?

    Fast Symbol Rendering is an improvement we made to the way MapInfo Pro renders point layers.

    Typically what happens is that all the points inside the map extent would get rendered one at a time and this would be saved to a bitmap which finally would be shown on the screen.

    The improvement we put in place checks if a point already has been rendered at a given pixel before rendering the point. This check prevents MapInfo Pro from rendering multiple points on top of each other as you wouldn't be able to see this anyway.

    The benefit of this simple check is a much faster rendering time for point layers.

    How much faster is it?

    The more points your table holds, the better the improvement. And the closer the points are, the better the improvements.

    Let's look at an example. Below you can see a map with the POI data from the Precisely World Point of Interest dataset for Austria.

    This dataset holds close to 1.4 million points with more than 50 columns. The file size of the .DAT file is close to the 2GB limit of a Native Tab file.

    When I open a workspace with the map below in MapInfo Pro v2019 with the Fast Symbol Rendering preference set to off, it takes 15 seconds to load and display the points on a map. If I turn on Fast Symbol Rendering, MapInfo Pro can display the points in less than 6 seconds.
    ​If I compare this to MapInfo Pro v15.0, the difference is even bigger. MapInfo Pro v15.0 takes 30 seconds to open the workspace and display the points on the map.

    Where do I manage Fast Symbol Rendering?

    Fast Symbol Rendering is one of the Output preferences. On the Backstage (the Pro tab), go to Options and click on Output Settings.

    You find Fast Symbol Rendering on the Display tab in the Output Preferences dialog.

    What should you be aware of when using Fast Symbol Rendering?

    When you are rendering the entire layer with the same symbol, you are not running into any issues with the Fast Symbol Rendering. In these situations, you can't tell how many points would be on top of each other anyway as they are rendered as one point, one symbol.

    The problems can arise if you render your layer with different symbol styles, especially if you can see through some of these symbol styles. In these cases, one symbol could be rendered with one symbol style, and another point at the same location should be rendered with a different symbol style that wouldn't hide the symbol style of the previous symbol style.

    Two issues we often hear of are the highway shields in the Precisely Street dataset and using the dispersed symbols.

    Here's a map rendered without Fast Symbol Rendering.

    Here's the same map rendered with Fast Symbol Rendering.

    In the image below, I have highlighted a few places where you can see a difference. Two points are at the same spot, the same pixel, but only one of them is drawn.

    As described above, Fast Symbol Rendering is a preference that affects all maps and all layers. It's either turned on or it is turned off for the current session.

    For the upcoming MapInfo Pro v2021 coming later this year, we are investigating if we can change this from being a session-wide setting to a setting either per map or maybe even per layer.

    What's your experience using Fast Symbol Rendering?

    ------------------------------
    Peter Horsbøll Møller
    Principal Presales Consultant | Distinguished Engineer
    Precisely | Trust in Data
    ------------------------------


  • 2.  RE: MapInfo Monday: Fast Symbol Rendering

    Posted 02-02-2021 07:32
    Edited by John Ievers 02-02-2021 07:34
    Hi Peter
    Just processed the AddressBase data for Great Britain.
    Over 113GB of data for 37 million records.
    The file loads in 1 second when focussed on just 1.25km window width.
    Without Fast Symbol Rendering takes 12 minutes.
    With Fast Symbol Rendering takes 1 min 50 secs.
    Not that I often want to display every record for the whole country!
    Full address details of properties in Great BritainNice colour....


    ------------------------------
    John Ievers
    CDR Group
    Hope Valley, United Kingdom
    ------------------------------



  • 3.  RE: MapInfo Monday: Fast Symbol Rendering

    Posted 02-02-2021 07:55
    Impressive dataset, John. Most hold a lot of attribute values.
    And luckily we do have support for Zoom Levels to prevent the dataset to be rendered at a country-wide zoom.

    Not only a nice colour, but it's also the right colour. If it's the true Precisely purple, of course ;-)

    ------------------------------
    Peter Horsbøll Møller
    Principal Presales Consultant | Distinguished Engineer
    Precisely | Trust in Data
    ------------------------------



  • 4.  RE: MapInfo Monday: Fast Symbol Rendering

    Posted 02-04-2021 11:19
    Of course, if it was in the olden days....
    Rainbow coloursActually, that took a while to produce!
    Large graphic selections from very large datasets is quite slow.
    SQL is much quicker.


    ------------------------------
    John Ievers
    CDR Group
    Hope Valley, United Kingdom
    ------------------------------



  • 5.  RE: MapInfo Monday: Fast Symbol Rendering

    Posted 02-04-2021 11:29
    I can assure you it would have been much slower back in the 32-bit versions.

    I recently compared selecting half a million points from a 1.4M point dataset with the Boundary Select tool. In v2019, it takes 39 seconds which isn't super fast but considering the amount it seems fair. Doing the same with v15.0, took 15... minutes or 960 seconds.

    With your big dataset, it would also be fast to put the table in FastEdit mode before doing any updates. That of course comes with the drawback of not being able to regret your changes.

    ------------------------------
    Peter Horsbøll Møller
    Principal Presales Consultant | Distinguished Engineer
    Precisely | Trust in Data
    ------------------------------



  • 6.  RE: MapInfo Monday: Fast Symbol Rendering

    Posted 02-04-2021 11:30
    PS: I can of course not comments on what old product (cough *MapInfo*) logo you are referring to with those colors :-)

    ------------------------------
    Peter Horsbøll Møller
    Principal Presales Consultant | Distinguished Engineer
    Precisely | Trust in Data
    ------------------------------



  • 7.  RE: MapInfo Monday: Fast Symbol Rendering

    Posted 02-24-2021 00:48
    When installing 64bit Mapinfo first time, this setting is initialized in the new 64bit MapInfoPro.pref file to default On globally (regardless of old 32bit setting in mapinfow.prf) has caused alot of support calls as previous 32bit workspaces open looking differently (opening up millions of points is an edge case, having different symbols in a thematic or static layer isn't).
    Hopefully this is changed to per layer option saved in the workspace, with the installation default being off to match old versions.

    Another annoying default is image processing (reprojecting) being default off... everyone had this set on in 32bit to reproject images, because that is what any other GIS does.

    ------------------------------
    Joshua Knight
    Datamine Australia Pty Ltd
    Kew VIC
    ------------------------------