How to Make Autodesk Viewer Orthographic by Default

Question

I am trying to make the autodesk viewer display files in orthographic mode by default. So far the best solution i've come up with is the following:

forgeViewer.addEventListener(
    Autodesk.Viewing.GEOMETRY_LOADED_EVENT,
    function setOrtho() {
      forgeViewer.autocam.homeVector.isPerspective = false;
      forgeViewer.autocam.homeVector.isOrtho = true;
      forgeViewer.autocam.originalHomeVector.isPerspective = false;
      forgeViewer.autocam.originalHomeVector.isOrtho = true;
      forgeViewer.autocam.toOrthographic();
    },
  );

This sets home to orthographic and sets the current view to orthographic which is exactly what i'm looking for. The only issue i have is that waiting on the GEOMETRY_LOADED_EVENT means that larger models will load in perspective and then snap to orthographic when all of the geometry is loaded, which can be jarring for users.

Is there a way to get the viewer to initialize in orthographic sooner so that it doesn't do this? I've tried waiting on a few other events as well as running setOrtho immediately with no event listener and usually it fails to get picked up.

score 3 · Accepted Answer · answered Aug 14 '19 at 03:04

You can set orthographic view as early (and might work even earlier) as Autodesk.Viewing.MODEL_ROOT_LOADED_EVENT:

NOP_VIEWER.addEventListener(Autodesk.Viewing.MODEL_ROOT_LOADED_EVENT, ()=>{
   //...
}

See live demo here - LGTM.

You can also try viewer.debugEvents(true) (and here's the doc to explain them) to print all the events to console and see which one gets called earlier to suit your needs.

How to Make Autodesk Viewer Orthographic by Default

1 Answers1