--- title: HTML5 Canvas and globalCompositeOperation | daily.dev description: A 2010 demo exploring HTML5 Canvas's globalCompositeOperation property to build a scratch-off effect. Covers how different composite modes like 'source-over',... canonical: https://daily.dev/posts/html5-canvas-and-globalcompositeoperation-af91jrbpf twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: HTML5 Canvas and globalCompositeOperation | daily.dev og:description: A 2010 demo exploring HTML5 Canvas's globalCompositeOperation property to build a scratch-off effect. Covers how different composite modes like 'source-over',... og:url: https://daily.dev/posts/html5-canvas-and-globalcompositeoperation-af91jrbpf og:image: https://api.daily.dev/og/posts/af91jrBpf.png og:image:alt: HTML5 Canvas and globalCompositeOperation og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # HTML5 Canvas and globalCompositeOperation **[Beej's Blog](https://daily.dev/sources/beej)** · 2 min read · 0 upvotes · 0 comments ## Summary A 2010 demo exploring HTML5 Canvas's globalCompositeOperation property to build a scratch-off effect. Covers how different composite modes like 'source-over', 'source-atop', and 'source-out' affect how drawing operations interact with existing canvas content. Notes browser compatibility issues with 'source-out' in Firefox, and briefly mentions an alternative approach using clip() for masking. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [The Web Is Fun Again: First Experiments with HTML in Canvas – Frontend Masters Blog](https://daily.dev/posts/the-web-is-fun-again-first-experiments-with-html-in-canvas-frontend-masters-blog-n0q3syc0y) · Frontend Masters · 3 upvotes · 0 comments - [Exploring the HTML-in-Canvas Proposal](https://daily.dev/posts/exploring-the-html-in-canvas-proposal-62dkmwqtx) · Codrops · 2 upvotes · 0 comments - [Canvas UI Ships 35 HTML-in-Canvas Components That Run WebGL and WebGPU Effects Over Live DOM](https://daily.dev/posts/canvas-ui-ships-35-html-in-canvas-components-that-run-webgl-and-webgpu-effects-over-live-dom-tfekmd60e) · InfoQ · 0 upvotes · 0 comments --- Tags: [#webdev](https://daily.dev/tags/webdev), [#javascript](https://daily.dev/tags/javascript) [View this post on daily.dev](https://daily.dev/posts/html5-canvas-and-globalcompositeoperation-af91jrbpf) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"HTML5 Canvas and globalCompositeOperation","url":"https://daily.dev/posts/html5-canvas-and-globalcompositeoperation-af91jrbpf","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/html5-canvas-and-globalcompositeoperation-af91jrbpf"},"datePublished":"2026-03-31T12:28:02.737Z","dateModified":"2026-03-31T12:40:33.731Z","description":"A 2010 demo exploring HTML5 Canvas's globalCompositeOperation property to build a scratch-off effect. 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