如何使 canvas 按比例响应？

Question

I am currently working on a pong game with angular for the frontend, the game is drawn inside an html canvas.

here is the html code:

<div style="height: 70%; width: 70%;" align="center">
        <canvas id="canvas-container" width="950" height="525" style="width: 100%;"></canvas>
</div>

The canvas get proportionally responsive when I reduce the window on the width but it doesn't work the same on the height. See photos below:

Before reducing the window: After reducing the width of the window: After reducing the height of the window:

As you can see when I reduce the height it doesn't work the same as the width, is there a way to make the height of my canvas as responsive as the width?

EDIT

When I use vmin instead of % for the css width of the canvas it fixes the problem but another one came. See photos below:

When I totally reduce the window: When I totally reduce the window only on the width:

Answer 1

var document= document.getElementById("canvas-container");

var width = window.innerWidth || document.clientWidth;

var height = window.innerHeight || document.clientHeight

Answer 2

You always can use fromEvent rxjs operator

  //declare an observable
  height$ = fromEvent(window, 'resize').pipe(
    startWith(null),
    map((_) => {
      const factor = 525 / 925; //relation original: height/width
      const width = window.innerWidth - 50;
      const height = window.innerHeight - 50;
      if (height > width * factor)
        return { height: width * factor, width: width };
      return { height: height, width: height / factor };
    })
  );

And use like

<div *ngIf="{ dim: height$ | async } as dim">
  <canvas
    #myCanvas
    style="background-color:yellow"
    [height]="dim.dim.height"
    [width]="dim.dim.width"
  ></canvas>
</div>

See stackblitz

Answer 3

After many tests I found out that the best solution my issue was to use vmin unit for the css of my canvas on the width and the height respecting the aspect ratio(55% of the width is the height)

<canvas #gameCanvas id="canvas-container" width="950" height="525" style="width: 100vmin;height: 55vmin;"></canvas>