Performance problem: Window module causing unnecessary layout reflow

[w0rm]

In the Runtime code there is a draw function that checks for Window module and calls resizeIfNeeded if it exists.

function draw()
{
    update(elm.node.firstChild, savedScene, scheduledScene);
    if (elm.Native.Window)
    {
        elm.Native.Window.values.resizeIfNeeded();
    }
    savedScene = scheduledScene;
}

resizeIfNeeded calls node.clientWidth and node.clientHeight that trigger layout reflow.

Because draw function happens very often, this affects the performance and makes it impossible to use Window module to calculate dimensions in HTML5 games that render on every requestAnimationFrame.

[w0rm]

Seems that this is in the project from the old times, tracked the resizeIfNeeded call down until this commit elm-lang@1af7914

[w0rm]

Seems that this is in the project from the old times, tracked the resizeIfNeeded call down until this commit elm-lang@1af7914

[w0rm]

Below are two timelines of HTML5 game, one before, and another one after I deleted resizeIfNeeded call from the draw function.

You can see that the second one is mostly green with the frames painted in less than 20ms.

The question is, why is it there in the first place, and can it be removed?

[w0rm]

Below are two timelines of HTML5 game, one before, and another one after I deleted resizeIfNeeded call from the draw function.

You can see that the second one is mostly green with the frames painted in less than 20ms.

The question is, why is it there in the first place, and can it be removed?

[evancz]

I guess it can be removed. I do not think elm-lang/window will have this issue.

[evancz]

I guess it can be removed. I do not think elm-lang/window will have this issue.