Update Time keep changing

sooyong_Kim · February 8, 2023, 6:55am

I’ve disabled autoRender and renderNextFrame manually and checked this statistic and found that the “Update Time” keeps counting.

Can anyone kindly explain me when it means?

Thanks.

Leonidas · February 8, 2023, 7:50am

Hi @sooyong_Kim,

To stop scripts updating you should set the timeScale property to 0.0:

this.app.timeScale = 0.0;

yaustar · February 8, 2023, 10:00am

Those parameters just stop the rendering, not the update loop. The update is still being called every frame.

Even if you set the timeScale to 0, the update loop is still called but with a deltatime of 0.

Leonidas · February 8, 2023, 1:01pm

Quite true, I should have written that differently, thanks @yaustar !

sooyong_Kim · February 15, 2023, 5:57am

What about MS value?
Even after I set autoRender and renderNextFrame to false and timeScale to 0.0, the MS value keep
changing.

Is it normal behavior??

Leonidas · February 15, 2023, 7:48am

Yes, that is the browser request animation frame time, registered as frame update here:

github.com

playcanvas/engine/blob/main/src/framework/app-base.js#L2162

      
        
            if (application.graphicsDevice.contextLost)
                return;
            
            
application._fillFrameStatsBasic(currentTime, dt, ms);
            
            
// #if _PROFILER
            application._fillFrameStats();
            // #endif
            
            
application._inFrameUpdate = true;
            application.fire("frameupdate", ms);
            
            
let shouldRenderFrame = true;
            
            
if (frame) {
                shouldRenderFrame = application.xr?.update(frame);
                application.graphicsDevice.defaultFramebuffer = frame.session.renderState.baseLayer.framebuffer;
            } else {
                application.graphicsDevice.defaultFramebuffer = null;
            }

sooyong_Kim · February 15, 2023, 7:49am

Can I even disable and enable it??

Leonidas · February 15, 2023, 7:50am

I don’t think so, you will have to patch the engine and add a condition on when this.tick() executes here:

github.com

playcanvas/engine/blob/main/src/framework/app-base.js#L1125

      
        
                    this.onLibrariesLoaded();
                }
            
            
    this.systems.fire('initialize', this.root);
                this.fire('initialize');
            
            
    this.systems.fire('postInitialize', this.root);
                this.systems.fire('postPostInitialize', this.root);
                this.fire('postinitialize');
            
            
    this.tick();
            }
            
            
/**
             * Update all input devices managed by the application.
             *
             * @param {number} dt - The time in seconds since the last update.
             * @private
             */
            inputUpdate(dt) {
                if (this.controller) {

Albertos · February 16, 2023, 8:15am

sooyong_Kim · February 16, 2023, 1:53pm

I’ve temporarily tested it with console window and seems working fine.
Is there any known side effect if I apply it???