Talk:Canvas element

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High traffic

On 26 May 2010, Canvas element was linked from Slashdot, a high-traffic website. (See visitor traffic)

broken link[edit]

in: Tucanos - The tucanos demo

Examples list - mostly spam?[edit]

Having a third of this article dedicated to examples is absurd. The list should be concise, to the point, non-spammy links to good examples of Canvas being implemented, not just a list of arcade games redone for the browser in Canvas. 16:14, 19 April 2007 (UTC)

Rather than link to lots of smaller demos, would it not be better to link to a site repository which contains links to most of these demos and tutorials? Check out Andi553 (talk) 00:09, 31 March 2009 (UTC)

Intellectual Property Issues[edit]

This section talks about an email from March 07. In April, there was an email from to the w3c public-html list that said:

"If the group is agreeable to these proposals, Apple, Mozilla and Opera will agree to arrange a non-exclusive copyright assignment to the W3 Consortium for HTML5 specifications."

I don't know the details of this debate, but perhaps the section should be updated to reflect this?

The page says: "This caused considerable discussion among web developers, as Apple is known for its history of patent-related litigation." That seems to be an inflamatory statement. Following the link shows only a single example of a patent-related litigation, and it involves Apple being sued by Creative. There isn't a single example of Apple engagin in legal action against anyone for patent violation, so saying that "Apple is known for its history of patent-related litigation", is at best unsubstantiated ArnoGourdol 18:20, 25 May 2007 (UTC)

I think that's an excellent point. I've chopped out the offending text, and spliced it together with the concern over a lack of patent policy. (Which has been the real discussion in regards to Apple's email.) --Jbanes 18:51, 25 May 2007 (UTC)
I think that this needs to be revised again. Apple is rather notorious for patent litigations now.Fduch (talk) 02:39, 25 December 2011 (UTC)


I think the example code could be much simpler, along the lines of the Mozilla Canvas tutorials.

It's too long, and not focused on the features of Canvas itself. —Preceding unsigned comment added by Samdutton (talkcontribs) 18:56, 13 February 2009 (UTC)

Use of NoMoreLinks template[edit]

Look, this is simple. Reisio (talk · contribs) and I have been going back and forth about removing the NoMoreLinks template from the External links section of this page. I believe it should be there to dissuade people from adding more links, but Reisio feels that "few useless & redundant things in this world are _meant_ to be UNhelpful, but they remain useless & redudant" (this edit). Since I'd rather not go back and forth on this, I've requested a WP:3O. So to the person giving the opinion: should the NoMoreLinks template be included? — HelloAnnyong (say whaaat?!) 20:14, 7 June 2009 (UTC)

I'd say toss it. AFAICT, it's a largely un- and sub-standard template, and I would personally highly discourage its use. It's also pretty disruptive, and the same thing could be accomplished by just writing <!--Excessive or inappropriate links will be deleted. See Wikipedia:External links for details.--> That way, it's unobtrusive, non-threatening, and clear-cut. You don't even need the second sentence. ~ Amory (talk) 20:33, 7 June 2009 (UTC)
Hmm, alright. I guess I haven't really seen it used much elsewhere. I assume that it was added at a time when this article was rife with crap external links, but it's not really that bad anymore. — HelloAnnyong (say whaaat?!) 20:47, 7 June 2009 (UTC)

It doesn't work, it bloats up the data, and it merely re-states Wikipedia policy & guidelines. There's simply no reason to use it anywhere. Nothing personal. ¦ Reisio (talk) 20:50, 7 June 2009 (UTC)

"Websites using canvas" submission[edit]

(apologizing right away for the lengthy post.  :P)

Hello, my name is Eric Reedy.

I'd like to submit the following link for the "Websites using canvas" section of this Wiki page:

  • Madcap Studios uses canvas to create an infinitely scalable, animated web user interface.

I'm a long time Wiki-user, but haven't spent much (if any) time editing. I own a small company called Madcap Studios, inc., where we primarily do Web and iPhone Programming. Our projects so far have all been free (Art Book should be on the App Store within a week, and Tooltipr will be available as soon as we finish it's page on the site).

Tooltipr itself is a light-weight website addon (about 10kb) that you include in your site's header, and it allows you to add dynamic tooltips to any element on your site with a single HTML value. Complete cross-browser compatibility has always been a major goal for us. When we first started working on Tooltipr, we had an elaborate system to work with PNGs to construct the tooltip graphic, and degrade to GIFs in IE6 and older. That worked fine for single line tooltips, but we noticed quickly that when you get to 2+ lines it became a huge hassle making them grow correctly. While I was exploring other possibilities I remembered hearing about Canvas, and it's original intended use for Dashboard in Mac OSX. After researching a bit I thought it sounded great, and decided to run some tests and learn how to use it. After a couple of days I had figured out the basics, communicated it to my team, and integrated it into the system.

RC1 of Tooltipr now supports 100% canvas themes (including animations, like color and opacity fades!) (which are about ~5kb on average) and super-small alteration files that tweak things like color values, animation speed, stroke, padding, offsets, etc. So for example we have a theme called "Glossy" and alterations called "Ruby" "Amethyst" "Sapphire" etc.

So that's part of the story.

The next part is the website itself. We wanted to build a nice website - which is easy to do. I'm a graphic artist and web/platform programmer myself, with additional programming muscle at our disposal. But at this point, after playing so much with Canvas, and knowing it's potential, I already knew what we had to do.

We decided it would be really cool to have a website where the entire UI is built using Canvas. That would allow for several things. Animations, gradients and opacity shifts that work in all major browsers, and infinite scalability - if we did things right. And we did!

Our website is - And it was built to stand as an example of just what Canvas is capable of, while communicating a little about ourselves. And it also has Tooltipr baked in. You can see that by hovering any of the Navigation links.

So what it comes down, is I'm requesting approval to add our URL to the "Websites using canvas" section. As I stated before, I'm very new to the editing system. I tried adding it in myself, and ended up with a 1 day block, because apparently adding your own URLs is a big no-no.

It was suggested by an administrator that I ask the community in the Canvas talk section and see if anyone agrees if it should be added or not.

So please, check out the site. Play with it a little. And let me know what you guys think.

There are very few canvas websites on the internet right now and I think ours stands as a great example of just what it's capable of.  :)


Madcap Studios (talk) 03:42, 27 October 2009 (UTC)

So.. you want us to add a promotional link to your website. Going to have to turn that request down, as it's a violation of WP:LINKSPAM. — HelloAnnyong (say whaaat?!) 04:09, 27 October 2009 (UTC)
No. (I had to make a new account due to a name issue) I'm not trying to add it for promotional purposes. It was an exercise in building a beautiful, dynamic website out of Canvas (the topic at hand) and it took us almost a month to complete. The fact it's MY website is the only real reason this is being disputed, and according to the WP:LINKSPAM, specific links may be allowed, and is primarily punishable if they are added repeatedly. I understand that I re-added it a couple of times yesterday, but that issue is resolved. I'm now aware of the rules, and am taking the advice of Admin JPGordon and asking those who are genuinely interested in the topic for their opinion on the matter.
In addition I feel you may be biased, as you were the one who originally undid my changes in the first place, leading to my 1 day ban. I request you, as an admin, remove your comment (and my reply) and listen to the Canvas (HTML element) editors on this one. The Madcapper (talk) 04:40, 27 October 2009 (UTC)
I appreciate you thinking so, but I'm not an admin. But I'm not going to remove my comment and "listen to the Canvas editors" - that's just you here. Your accomplishments on that page aren't currently notable in the eyes of Wikipedia. Per WP:ELNO #4, one type of link that should be avoided is "Links mainly intended to promote a website." And that's what we have here. You've given no other justification for why it should be included other than "it took me a long time to build and it was a beautiful dynamic website". — HelloAnnyong (say whaaat?!) 12:32, 27 October 2009 (UTC)
I've repeatedly denied that accusation, and gave a relevant reason you seem to ignore: The section REQUESTS (actually asks for people to add more links, with a direct link to the edit page) additional websites that use the Canvas HTML element. Our site not only uses the Canvas element, but it it built entirely of them. And the reason it's important to mention that it's "beautiful" and "dynamic" is because those are both attributed to the Canvas aspect.
Frankly based on your behavior here, in addition to the many discussions in your talk page, you seem to be a rather abusive editor, and you take your voluntary job far too personally. You're in here swearing up and down that my website doesn't belong on that list, yet I doubt you know the first thing about this topic, other than at most what is said on the topic page. The Madcapper (talk) 13:40, 27 October 2009 (UTC)
First, no personal attacks; comment on the content, not the editor. Second, I can tell you that I do know more about the topic than you think. And even still, that's largely irrelevant - we have policies and guidelines in place here, and it is certainly possible to determine whether or not a link is acceptable based on those guidelines without having a personal attachment to the topic. — HelloAnnyong (say whaaat?!) 14:48, 27 October 2009 (UTC)
In-article lists like this are typically restricted to listing things that have, or would qualify for a full article on Wikipedia. Mr.Z-man 04:17, 27 October 2009 (UTC)
Well you did say yourself that they are "typically" restricted, not "always". In this case I came forward and asked the opinion of those interested in this specific topic to make an exception. I respect your opinion if you don't think it's fitting for the topic, though. The Madcapper (talk) 04:40, 27 October 2009 (UTC)

Namespace issue[edit]

From the article (reactions): "There are other concerns about syntax e.g. the absence of a namespace." [my emphasis]

From reading the reference to this claim it seems to me that this is a problem of HTML not being capable of handling proprietary element tags in a good way, as it lacks namespaces. Thus it's not a problem with the canvas element. Since the canvas element now seems to become part of the official standard, this is no longer an issue, thus this claim is invalid.

Can someone please verify this? --Gosub (talk) 09:58, 4 March 2010 (UTC)

Support library links[edit]

MoreNet (talk · contribs) has repeatedly added links within the article to outside libraries. These violate WP:ELNO and should not be included. I've gone through and altered the text, but those links should definitely not be included. This isn't a place to advertise for whatever libraries are out there. If people want to find them, they can do a simple search. — HelloAnnyong (say whaaat?!) 16:19, 5 March 2010 (UTC)

Having little knowledge of canvas before visiting the page I found the absence of information on external libraries confusing. It was only somewhat by chance that i discovered the existence of these 'libraries' and alarmed by their omission have returned to suggest their inclusion.
"It is not natively supported by any versions of Internet Explorer, but can receive support through external libraries" is in my opinion far too vague. It does not help explain the real world scenario of being able to implement canvas in cross-browser compatible way.
Expecting upon people that they search elsewhere without even pointing them in the right direction seems at odds with what to expect of an article. Including vital details like these is surely notable and within the remit of wikipedia.
MoreNet (talk · contribs)'s edit appears reasonable and features improved separation of the content in comparison to what is currently there. I would be happy to see it reverted back to his edit. However if linking is frowned upon, perhaps just an unlinked section of text or a bullet list can be devoted to the libraries out there.
Crowdofone (talk) 07:19, 24 March 2010 (UTC)
You're new to Wikipedia and may not be familiar with the rules, but Wikipedia is not a how-to, or a manual or guide. It's not here to teach people how to use the canvas element; this article should talk about the element's history, current support and so on. If you want information like that, try searching on Google or something. — HelloAnnyong (say whaaat?!) 14:17, 24 March 2010 (UTC)
Wikipedia is meant to be practially useful, and not a place to have edit wars. Better a bit too much than too little. Just reverting others edits will discourage contribution. I suggest you focus on contributing rather than deleting. Tuntable (talk) 08:14, 28 April 2010 (UTC)

Lack of support in IE[edit]

Should we say anything about the lack of support in IE? I know that the code at the top of the page does give a kind of "alt text" but it says nothing about why you might need it. —Preceding unsigned comment added by Inputdata (talkcontribs) 14:40, April 29, 2010

Deeming from Comparison of layout engines (HTML5 Canvas) there seems to be an incomplete (as in all browsers) support of the Canvas element in latest IE, so the note is obsolete. Rursus dixit. (mbork3!) 11:23, 20 July 2011 (UTC)

Recent IP edits[edit]

I'm going to revert this set of edits yet again for a few reasons. First, the text in it is inappropriate: "Shapes and text rendered in canvas are immediately turned into pixels and their deeper meaning is lost" is editorializing. A statement like "their deeper meaning is lost" has nothing to do with anything, and should at the very least be given a reference. Second, and more importantly, the text being added is original research. Twitter is definitely not a reliable source, and is some random guy's personal site. If it was attributable to someone who's knowledgeable in the canvas element it would be one thing, but it's not. Similarly, is a personal blog, and that violates WP:RS. So maybe once we get some sources we can get this stuff in as long as it's written neutrally, but it's not acceptable in its current form. — HelloAnnyong (say whaaat?!) 21:49, 13 May 2010 (UTC)

Don't rush with reverts! C'mon! It's easier to delete than to write. Here's the reference for deeper meaning: Quoting: "there are no methods to assign roles, states and properties to areas of a canvas that represent widgets, controls or links. " (talk) 21:52, 13 May 2010 (UTC)
Blogs are unreliable sources. — HelloAnnyong (say whaaat?!) 21:55, 13 May 2010 (UTC)
It's blog post by Steve Faulkner, member of W3C HTML Working Group, who focuses on accessibility issues, and wikipedia policy is: "Blogs are a type of publishing format. They are not inherently reliable or unreliable. For the purpose of Wikipedia editing, determination of a blog's reliability is largely based on the relevance and professional standing of the writer." —Preceding unsigned comment added by (talk) 22:09, 13 May 2010 (UTC)

Alright, I don't know what's going on here with the multiple IPs; I assume it's the same person on an ISP that dynamically assigns IPs. Either way, this text is still unacceptable. Forums such as are also not reliable sources since the text contained in them can't directly be verified. Similarly, a buglist report (like this one used) and a slideshow on aren't acceptable either. I know you want to get this text onto the page, but without proper sourcing, it really can't be added. Some of the other text, like "Both are implemented in modern browsers and partially usable in Internet Explorer with help of scripts and plugins", is redundant - take a look at the Support section lower down, where it says "It is not natively implemented by Internet Explorer as of version 8[7], however many of the Canvas element's features can be supported via JavaScript libraries". It doesn't need to be stated twice.

In reading the text you're adding, it's clear that you have a point of view to push that's anti-canvas element. Adding such a slant on the text is unacceptable on Wikipedia. Now having said that, I'm going to implement some of the changes: the text where you added the citation needed, I'm just going to remove; it's a little too advert-y for me. — HelloAnnyong (say whaaat?!) 14:35, 14 May 2010 (UTC)

Bugreport is text on with content verifiably signed by people who have authority on the matter. Please focus on quality of the content, rather than rejecting source because of its form (just like you've rejected expert's blog because it's a blog).
Those other IPs are not from my ISP. I've asked for opinion of other people, because you clearly have your own strong pro-canvas point of view and you keep reverting to text that has less sources than my version. I feel that my text gets more scrutiny that the poor-quality unsourced text you keep reverting to. (talk) 18:19, 14 May 2010 (UTC)
Okay, well, meatpuppeting, where you get other people to come here and side with you, is a violation of Wiki policy. So too is canvassing if it's not done the right way. As to the sourcing, using inappropriate sources is definitely not better than unsourced. Having said that, I don't necessarily agree with the text on this page, but I'm not going to watch it be worsened by poor sourcing. And I definitely don't have a pro-canvas point of view; honestly I don't care about the tag one way or another. — HelloAnnyong (say whaaat?!) 19:15, 14 May 2010 (UTC)
If links to pages on the W3C Consotrium, which can only be edited by verified members who designed canvas in the first place, are not good enough sources for you, then I don't know what is.= I'm really disappointed that such petty bureaucracy prevents me from adding important information to the article, but I'm tired of arguing with you and I'm giving up on this.—Preceding unsigned comment added by (talkcontribs) 14:51, May 14, 2010
I came here to respond to a filed third opinion request, but it appears there's no longer a dispute given the anonymous editor's giving up/departure from Wikipedia. Either party should feel free to refile if so desired. WCityMike 22:12, 16 May 2010 (UTC)

Summer in which hemisphere?[edit]

In the history section there is a reference to "summer 2009". I can presume that this means the Nortern Hemisphere, however it would be very useful if this reference could be changed to either a month, or to indicate which hemisphere's summer. Thanks. Gregwmay (talk) 01:42, 15 June 2010 (UTC)

 Done. I think it was August 2009. — HelloAnnyong (say whaaat?!) 22:30, 16 June 2010 (UTC)

existed in netscape[edit]

The canvas tag existed in netscape a while back (1997-8) as far as i remember! —Preceding unsigned comment added by (talk) 08:44, 22 February 2011 (UTC)


Now I've tested HTML5/canvas/CanvasRenderingContext2D. It is essentially a syntax-morphed PostScript in ECMAScript — a Display PostScript I presume. (IMO a technically bad solution, but why should anyone listen to the programmer?). I'm starting to get an idea why this beastie is being approved by the code mongers: it's easily hackable within the imperative-pseudo-OO paradigm, but that refers to CanvasRenderingContext2D. (IMO it should have been the log-prog paradigm instead — many security and garb issues are expected to rise in the future.) I think we should find sources and claim that the beastie is a Display PostScript. Rursus dixit. (mbork3!) 11:34, 20 July 2011 (UTC)

canvas scope[edit]

no one seems to be bothered that this page:

1) refers to "canvas" as a html5 thing

2) does not point to a disambiguation page for other meanings:

2.a) where canvas refers to a real painter canvas

2.b) where canvas refers to a software abstraction for a screen representation (talk) 18:36, 22 July 2011 (UTC)

I don't see the problem the page is called canvas element not canvas so there is not a issue with other meanings. If you search for just canvas you a painter canvas Inputdata (talk) 08:43, 31 August 2011 (UTC)

External link question[edit]

Something I was hoping to find in the external links, but didn't: a simple(r) explanation of what HTML5 canvas is, suitable for typical naive end users. I'd really like to provide a good link on a site I'm building, so that anyone whose browser lacks HTML5 canvas is aimed at an appropriate page to understand what canvas is. This article itself is probably one step to sophisticated to be the preferred target of that link.

Any suggestions? - Jmabel | Talk 01:09, 15 November 2011 (UTC)

Canvas Element and 3D Graphics[edit]

As it stands, this article seems to imply that the Canvas element is only for 2D graphics, but one can also render 3D graphics in a Canvas element. As I write this, there are two APIs for drawing inside a Canvas element (according to the WHATWG wiki):

  1. a 2D drawing API that doesn't really have a nice compact brand name other than the "HTML Canvas 2D Context", and
  2. the WebGL API which is for 3D graphics.

Drttm (talk) 19:53, 4 March 2012 (UTC)

EL for canvas draw-to-script generator?[edit]

This edit recently added the WP:EL:

[ HTML Canvas Studio to generate Canvas script by drawing]

but was reverted soon afterwards.

I'm inclined to re-add it. It's not a script itself that I would find much use for, however it (and the scripts it generates) does give a simple and comprehensible example of <canvas> and why one might wish to use it. Thoughts? Andy Dingley (talk) 14:22, 23 June 2013 (UTC)

External links should elaborate on the subject. This is just a tool, one of many available on the WWW; it belongs in a web directory, not a Wikipedia page. Mindmatrix 19:49, 23 June 2013 (UTC)
I see this as more an example than a tool (or an elaboration of textual detail). It's an interactive demonstration of what can be achieved by using <canvas>, and an example of the sort of code which one would write to do so. These are both useful, encyclopedic, yet outside the technical scope of what can be achieved in a written encyclopedia. For that reason I see it as meeting WP:EL. Andy Dingley (talk) 20:53, 23 June 2013 (UTC)

Link to online Canvas Handbook[edit]

I wrote a free online Canvas Handbook as an introduction and comprehensive reference for this HTML5 element. Maybe it is suitable to be added to the list of external links. — Preceding unsigned comment added by Bucephalusorg (talkcontribs) 16:54, 8 October 2013 (UTC)

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