Blazorex

Description

Blazorex is an HTML Canvas wrapper library for Blazor.

It has some interesting functionalities like:

multiple canvases
background rendering
image rendering
procedural image generation (yes, the fire on the background is fully procedural! Thanks filipedeschamps for the awesome repository showing how to render the Doom fire! )

Installation

Blazorex can be installed as Nuget package: https://www.nuget.org/packages/Blazorex/

Usage

Simple scenario

Just add the Canvas Component to your Razor page and register to the OnCanvasReady to receive the CanvasBase instance.

Then use OnFrameReady to define your update/render logic:

<Canvas Width="800" Height="600" 
        OnFrameReady="(t) => OnFrameReady(t)"
        OnCanvasReady="(ctx) => OnCanvasReady(ctx)" />

@code{
    CanvasBase _canvas;

    private void OnCanvasReady(CanvasBase canvas)
    {
        _canvas = canvas;
    }

    private void OnFrameReady(float timeStamp)
    {
        // your render logic goes here
    }
}

You might also need to update your index.html to include the library's CSS:

<head>
    <!-- other tags... -->
    <link href="_content/Blazorex/blazorex.css" rel="stylesheet" />
</head>

Multiple Canvases

In case you want to have multiple canvases on the same page, you can use the CanvasManager component instead:

<CanvasManager @ref="_canvasManager" />

@code{
        CanvasManager _canvasManager;
        
        protected override async Task OnAfterRenderAsync(bool firstRender)
        {
            if (!firstRender)
                return;
        
            _canvasManager.CreateCanvas("myCanvas", new CanvasCreationOptions()
            {
                Width = 800,
                Height = 600,
                Hidden = false,
                OnCanvasReady = this.OnMyCanvasReady,
                OnFrameReady = this.OnMyCanvasFrameReady,
            });
        }
}

You simply have to get a reference to the CanvasManager and then call the CreateCanvas passing an instance of CanvasCreationOptions with the desired parameters.

For a complete list of options for Canvas initialization, see here.

The ./samples folder contains some examples of how to setup the canvas and draw some cool stuff :)