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getLasltFrameDuration - HOW


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function getDeltaTime() { 
   return scene.getLastFrameDuration() / 1000; 


How can I get same function with EngineInstrumentation? I am playing around instrumentation.
Can any body help me getDeltaTime? getLastFrameDuration is not working anymore.

Which counter can get me solve getDeltaTime like code above?
Any help hint?


function instrumentFun() {
            console.log( "current frame time (GPU): " + (instrumentation.gpuFrameTimeCounter.current * 0.000001).toFixed(2) + "ms" );
            console.log( "average frame time (GPU): " + (instrumentation.gpuFrameTimeCounter.average * 0.000001).toFixed(2) + "ms" );
            console.log( "total shader compilation time: " + (instrumentation.shaderCompilationTimeCounter.total).toFixed(2) + "ms" );
            console.log( "average shader compilation time: " + (instrumentation.shaderCompilationTimeCounter.average).toFixed(2) + "ms" );
            console.log( "compiler shaders count: " + instrumentation.shaderCompilationTimeCounter.count );


I am useing chrome (with debian) And I get "current frame time (GPU)" and "average frame time (GPU)"  0.
I always get 
current frame time (GPU): 0.00ms
average frame time (GPU): 0.00ms

Should I get also CPU time anyhow? Should I get also CPU frame time?
Can anybody help me code getDeltaTime function with instrumentations counters?

I test chrome with http://webglreport.com/ and I get
WebGL 1
Platform:    Linux x86_64
Browser User Agent:    Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.162 Safari/537.36
Context Name:    webgl
GL Version:    WebGL 1.0 (OpenGL ES 2.0 Chromium)
Shading Language Version:    WebGL GLSL ES 1.0 (OpenGL ES GLSL ES 1.0 Chromium)
Vendor:    WebKit
Renderer:    WebKit WebGL
Unmasked Vendor:    Intel Open Source Technology Center
Unmasked Renderer:    Mesa DRI Intel(R) Sandybridge Desktop
Antialiasing:    Available
ANGLE:    No
Major Performance Caveat:    No
Vertex Shader
Max Vertex Attributes:    16
Max Vertex Uniform Vectors:    4096
Max Vertex Texture Image Units:    16
Max Varying Vectors:    32
Best float precision:    [-2127, 2127] (23)
Transform Feedback
Coming in WebGL 2
Aliased Line Width Range:    [1, 7.375]
Aliased Point Size Range:    [1, 255]
Fragment Shader
Max Fragment Uniform Vectors:    4096
Max Texture Image Units:    16
float/int precision:    highp/highp
Best float precision:    [-2127, 2127] (23)
Max Color Buffers:    8
RGBA Bits:    [8, 8, 8, 8]
Depth / Stencil Bits:    [24, 8]
Max Render Buffer Size:    8192
Max Viewport Dimensions:    [8192, 8192]
Max Texture Size:    8192
Max Cube Map Texture Size:    8192
Max Combined Texture Image Units:    48
Max Anisotropy:    16
Uniform Buffers
Coming in WebGL 2
Supported Extensions:

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Hi @ian

I don't think you should use instrumentation at runTime in a production environment, if all you need is deltaTime, too much unneeded measuring etc going on.

This will calculate the deltaTime from the start of last render and to the start of current/this render, 

var deltaTime = null;
var lastUpdate = null;
function updateDelta(){
    // Get timestamp in MS.
    var now = +new Date();

        lastUpdate = now;

    // Update deltaTime variable.
    deltaTime = now - lastUpdate;

    // Update lastUpdate to being now.
    lastUpdate = now;

     // return it incase the function is used as a "variable".
    return deltaTime;

// Using it..
// as Variable, after calling the function.
    myUiText.text = deltaTime.toString();

// as Function directly, if you only use it once.
    myUiText.text = updateDelta().toString();



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Hi again @ian 
I just notised that 


appears to work flawlessly in the latest versions (including stable),
I wrote the above code a few versions ago where it(engine.getDeltaTime()) was giving me some issues. and i also needed the full timestamp.
But it seems you can just use that instead :) 

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thank you aWerdo your previous answare works also fine.
I'll try tomorrow with engine.getDeltaTime on the latest babylon.js engine.

I don't know if babylon did fix this problem, so we will not nedd deltatime anymore.
The problem is if same things is running on PS (faster gpu)  or phone/tablet (slowest gpu) ???

I don't know if rendering and physics works with same speed regardless of hardware (cpu,gpu) speed ???

Is there any playground example to test/see this?


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