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  • Members: 196
  • Category: Web Design
  • Founded: Nov 26, 2005
  • Language: English
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#344 From: "David Curran" <david.curran@...>
Date: Mon Jan 29, 2007 9:19 am
Subject: Re: Spamming will not be tolerated
iamreddave
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>Depends. You cannot fool Opera's content filtering by loading the image in
>JavaScript to then display it on a canvas, as the blocking is URL-based.
>What happens in other content blockers, I don't know.
The original ad blocker (Kusmerick) was based on location of an image in the page but most current ones are URL-based.

>If you are talking about generating the entire in-page ad using canvas
>without loading bitmaps into the canvas, it might be more problematic,
>unless you start blocking page elements based on element dimensions.
Good point unless you have a heuristic like "all wide shallow canvas tags at the top of a page of text are ads" blocking ads like this is difficult. For economic reasons web ads are url based rather then just simple billboards so you are probably correct that URL based schemes should continue to work.
     David


On 29/01/07, Arve Bersvendsen <arveb@...> wrote:

On Thu, 25 Jan 2007 16:56:16 +0100, David Curran <david.curran@... >
wrote:

> on a related note.
> How would you deal with canvas spam?
> Large amounts of spam now uses images files to convey the data. What
> would happen if vector based images were used instead? Could current
> techniques be adapted to recognise spam in canvas elements?

Canvas spam is highly unlikely to ever happen, as canvas is dependent on a
scripting engine. I do not know of one mail display engine in 2007 that
executes JavaScript.

> In a similar problem do canvas image ads bypass ad filters in browsers?

Depends. You cannot fool Opera's content filtering by loading the image in
JavaScript to then display it on a canvas, as the blocking is URL-based.
What happens in other content blockers, I don't know.

If you are talking about generating the entire in-page ad using canvas
without loading bitmaps into the canvas, it might be more problematic,
unless you start blocking page elements based on element dimensions.

--
Arve Bersvendsen, Web Applications Developer

Opera Software ASA, http://www.opera.com/




--
The old blog is dead. Long live the new blog
http://liveatthewitchtrials.blogspot.com/

#345 From: "matthew_hagston" <matthew_hagston@...>
Date: Mon Feb 19, 2007 8:49 pm
Subject: Changing color
matthew_hagston
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Anyone know of a way to re-color an image once it is loaded? I can't
seem to find a command to do that under canvas.

#346 From: Seldo V <seld0@...>
Date: Tue Feb 20, 2007 7:56 pm
Subject: Another 3D rendering engine using Canvas/JS
laurie.voss
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http://www.tapper-ware.net/2007/02/real-3d-rendering-right-inside-browser.html

Rather like CanvasScape in appearance, but rather more powerful under the hood. Performance seems pretty good on my laptop.

L.


TV dinner still cooling?
Check out "Tonight's Picks" on Yahoo! TV.

#347 From: "matthew_hagston" <matthew_hagston@...>
Date: Tue Feb 20, 2007 8:06 pm
Subject: Re: Has anyone tried dynamically resizing CANVAS?
matthew_hagston
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This is how i handle dynamically resizing the canvas fit inside a
table. I've only tested this in Firefox
though, i have not tested it in either opera nor safari ...


<table id=maintbl border=1 width=100% height=100%>
<tr><td valign=top align=left width=80% >
     <div style="position: relative; width: 100%; height: 450px;">
       <!-- SET MAIN ANIMATION AREA -->
    	 <canvas id='canvasBG' width="100%" height="450px" style='width:
100%; height: 450px; background-color: #000; position: absolute; top:
0px; left: 0px; background: black url("images/starbackground2.gif")
repeat top left;'></canvas>
    	 <canvas id='canvas' width="100%" height="450px" style='width:
100%; height: 450px; position: absolute; top: 0px; left: 0px;'></canvas>
       </div>
   </td><td valign=top>
  	 <canvas id='canvasDisplayOne' width=250px height=100px
style='width: 250px; background-color: #0F0;'></canvas>
     </td>
   <td width=120 height=600 rowspan=3>
	 <!-- Reserved space -->
     </td>
   </tr>
</table>

<script>

function resized() {
   document.getElementById('canvas').width =
document.getElementById('canvas').clientWidth;
   document.getElementById('canvasBG').width =
document.getElementById('canvasBG').clientWidth;
   document.getElementById('canvas').height =
document.getElementById('canvas').clientHeight;
   document.getElementById('canvasBG').height =
document.getElementById('canvasBG').clientHeight;
   }

function init(){
   resized();
   }

</script>

#348 From: "mohamed hassan" <m_hassan842002@...>
Date: Fri Feb 23, 2007 5:34 pm
Subject: 3d canvas tutorial
m_hassan842002
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Hi, every one

I have seen some canvas examples which seem to be using 3d graphics.

Can I find tutorials to explain how to make things like those?

Thank you very much.

#349 From: "lec_maj" <lec@...>
Date: Sun Feb 25, 2007 4:23 am
Subject: Re: 3d canvas tutorial
lec_maj
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I have not seen any tutorials, there is really no API yet for any of
this. Once we hear more about openGL ES like api then perhaps. I have
been trying to get in touch with folks at Mozilla developing this, but
no luck. For now everyone is on their own codding.

Few things I did want to mention, I hope to setup a wiki with some of
my code and tests, I will post it as soon as I get back into town.

If anyone knows of further development on 3d canvas please share it
with  the group, I think we are all eager to learn.

Best,
Lec

#350 From: Matthew Westcott <matthew@...>
Date: Mon Feb 26, 2007 10:34 am
Subject: Re: Re: 3d canvas tutorial
mmmgasman
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On 25 Feb 2007, at 04:23, lec_maj wrote:
> I have not seen any tutorials, there is really no API yet for any of
> this. Once we hear more about openGL ES like api then perhaps. I have
> been trying to get in touch with folks at Mozilla developing this, but
> no luck. For now everyone is on their own codding.
My Canvastastic library provides an API for doing low-poly 3D via the
2D canvas context, although it's a higher-level API than OpenGL:
http://matt.west.co.tt/category/canvastastic

Obviously, this is a very different beast to the native 3D support in
Canvas which should be coming any month now...

- Matt

#351 From: "Philip Taylor" <excors+yahoo@...>
Date: Mon Feb 26, 2007 1:36 pm
Subject: Re: Re: 3d canvas tutorial
excors_y
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On 26/02/07, Matthew Westcott <matthew@...> wrote:
> On 25 Feb 2007, at 04:23, lec_maj wrote:
> > I have not seen any tutorials, there is really no API yet for any of
> > this. Once we hear more about openGL ES like api then perhaps. I have
> > been trying to get in touch with folks at Mozilla developing this, but
> > no luck. For now everyone is on their own codding.

There's been some initial experimental code in the Mozilla tree for a
while, at http://lxr.mozilla.org/mozilla/source/extensions/canvas3d/ -
you have to compile it yourself but it does work for real (or it did
when I last tried). I did a primitive example at
http://canvex.lazyilluminati.com/3dmodel/example0.html [requires
Firefox, since it uses E4X to load COLLADA models] which renders with
Matt's Canvastastic by default but can also do fast textured models
with the GLES extension.

With a few modifications to the extension (particularly adding the
copyTexImage2D function) it also did real-time reflections on animated
bumpy water, which is quite nice. But it does take quite a bit of
effort to write a rendering engine just with OpenGL - if/when this
technology becomes usable on the web for real, I think it'd be
necessary to have a fairly-standard high level library that people can
program with, otherwise almost nobody will be able to write useful
code with just the interface provided by the browser.

(I expect it'd be fine to write that high level library in JavaScript
using the browser's GL interface, which is nice since it gives
ultimate control to the users if they want to modify the library or
make a totally new one; the only real problem is that it takes a long
time to load models (so an accelerated "download this file and load it
as an array of floats" would be nice (and could be integrated with
COLLADA easily), the same as how textures are already loaded as lumps
of binary data), but otherwise performance doesn't seem to be a
particular issue.)


All the existing 3D-in-2D-canvas examples seem kind of unpleasantly
hacky because of the limitations of the medium (affine transforms,
linear gradients, etc) - there isn't a standard way to do things,
because you have to make different tradeoffs depending on what you
want to end up with (e.g. textureless true 3D vs textured raycasting),
so there aren't really any guides to follow, and you just have to make
it up as you go along :-)

--
Philip Taylor
excors@...

#353 From: Vladimir Vukicevic <vladimir@...>
Date: Thu Mar 1, 2007 5:36 am
Subject: Re: Re: 3d canvas tutorial
vvukicevic
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Philip Taylor wrote:
> On 26/02/07, Matthew Westcott <matthew@...> wrote:
>> On 25 Feb 2007, at 04:23, lec_maj wrote:
>>> I have not seen any tutorials, there is really no API yet for any of
>>> this. Once we hear more about openGL ES like api then perhaps. I have
>>> been trying to get in touch with folks at Mozilla developing this, but
>>> no luck. For now everyone is on their own codding.
>
> There's been some initial experimental code in the Mozilla tree for a
> while, at http://lxr.mozilla.org/mozilla/source/extensions/canvas3d/ -
> you have to compile it yourself but it does work for real (or it did
> when I last tried). I did a primitive example at
> http://canvex.lazyilluminati.com/3dmodel/example0.html [requires
> Firefox, since it uses E4X to load COLLADA models] which renders with
> Matt's Canvastastic by default but can also do fast textured models
> with the GLES extension.

Hey, that's pretty awesome!   That is, both your example and the fact
that you were able to build the canvas3d extension :)  Getting that out
is sitting at around spot #3/#4 on my todo list.. unfortunately,
something new that's more important has always come up in the past 4-5
months.  I suspect I'm going to have to go hide in the mountains for two
weeks and get enough done to get an initial release out soon, in hopes
of collecting enough feedback to be able to do a 1.0 in conjunction with
Firefox 3 at the end of the year.

The main issue blocking is an annoying linking one -- some of the
symbols that the extension wants aren't exported in released builds, and
I need to talk some sense into a few people until they agree with me
that they should be. ;)

> With a few modifications to the extension (particularly adding the
> copyTexImage2D function) it also did real-time reflections on animated
> bumpy water, which is quite nice. But it does take quite a bit of
> effort to write a rendering engine just with OpenGL - if/when this
> technology becomes usable on the web for real, I think it'd be
> necessary to have a fairly-standard high level library that people can
> program with, otherwise almost nobody will be able to write useful
> code with just the interface provided by the browser.

That's good to hear... I figure the final spec will be somewhere between
OpenGL ES and full OpenGL; OpenGL ES was just a much cleaner starting
point.  And I agree with you -- this isn't going to be an API that you'd
want to teach directly, but it is a flexible one on top of which more
usable JS middleware packages can be written.

> (I expect it'd be fine to write that high level library in JavaScript
> using the browser's GL interface, which is nice since it gives
> ultimate control to the users if they want to modify the library or
> make a totally new one; the only real problem is that it takes a long
> time to load models (so an accelerated "download this file and load it
> as an array of floats" would be nice (and could be integrated with
> COLLADA easily), the same as how textures are already loaded as lumps
> of binary data), but otherwise performance doesn't seem to be a
> particular issue.)

Yep, I'd love to figure out what these performance pain points are, and
then add native support for those.  Some API for fast loading of data is
pretty high on the list.

      - Vlad

#355 From: "Matthew Hagston" <matthew_hagston@...>
Date: Wed Mar 7, 2007 4:10 pm
Subject: Re: Build Your Website Entirely Using Cascading StyleSheets (CSS)
matthew_hagston
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Stupid spammers! die die die!

Spammers should be hung from the highest tree!

#356 From: "Andrew" <triptych@...>
Date: Wed Mar 7, 2007 4:22 pm
Subject: Membership change for canvas developers group...
triptych999
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I've changed the setting for this group to moderated membership. That
means anyone can still join, but I have to approve their membership.
It's more of a pain for me, but hopefully will help keep spammers from
leaving their droppings on this mailing list.

#357 From: "Andrew" <triptych@...>
Date: Wed Mar 7, 2007 4:19 pm
Subject: Re: Build Your Website Entirely Using Cascading StyleSheets (CSS)
triptych999
Send Email Send Email
 
User has been banned, removed and the email deleted from the mailing
list. Spammers will not be tolerated!!

#358 From: "Mario Giorno" <westphilly@...>
Date: Wed Mar 7, 2007 6:30 pm
Subject: Re: Membership change for canvas developers group...
pariahstudio
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Andrew,

     Thanks. I know it's a pain. I moderate the westphillyfreecycle Yahoo! group. The spam and unrelated posts are a pain in the backside, but it's worth taking the time to fleece them out. It makes everyone's experience in the group listserv so much more enjoyable and stress-free.


Mario Giorno
aka pariahstudio at Yahoo!

On 3/7/07, Andrew <triptych@...> wrote:

I've changed the setting for this group to moderated membership. That
means anyone can still join, but I have to approve their membership.
It's more of a pain for me, but hopefully will help keep spammers from
leaving their droppings on this mailing list.



#359 From: "tml" <tml135@...>
Date: Sat Mar 10, 2007 2:37 pm
Subject: canvas clipping overflow
firstoneonsun
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Hi,

I have a big canvas which is clipped and put inside a smaller div so
it looks similar to google maps. User can move the canvas around by
holding mouse button.

When I load the page I draw stuff onto the canvas, and then set the
clipping appropriately. In firefox 2 (only on linux) I notice, after
clipping, I see the previous lines in the background all over the
page. Its as if the inital drawing is still there, overlapped with all
the text and other stuff around the canvas'es div.

I'm not sure why this is happening, and it i only saw this on ff2 on
linux (ubuntu). Its fine on firefox windows and mac.

Does anyone know why this might be happening?

thanks,
tml

#360 From: "Matthew Hagston" <matthew_hagston@...>
Date: Mon Mar 12, 2007 2:54 pm
Subject: Re: canvas clipping overflow
matthew_hagston
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--- In canvas-developers@yahoogroups.com, "tml" <tml135@...> wrote:
>
> Hi,
>
> I have a big canvas which is clipped and put inside a smaller div so
> it looks similar to google maps. User can move the canvas around by
> holding mouse button.
>
> When I load the page I draw stuff onto the canvas, and then set the
> clipping appropriately. In firefox 2 (only on linux) I notice, after
> clipping, I see the previous lines in the background all over the
> page. Its as if the inital drawing is still there, overlapped with all
> the text and other stuff around the canvas'es div.
>
> I'm not sure why this is happening, and it i only saw this on ff2 on
> linux (ubuntu). Its fine on firefox windows and mac.
>
> Does anyone know why this might be happening?
>
> thanks,
> tml
>


I don't run linux so can't help you much there. It may help others
answer your question though if you post your code.

#364 From: "Matthew Hagston" <matthew_hagston@...>
Date: Fri Mar 16, 2007 4:08 pm
Subject: second image getting cut-off in firefox
matthew_hagston
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It's drawing the first piece of track just fine, but when i go to draw
the second piece of track it only draws a small corner and doesn't
draw the whole image.

It seems to draw only in the transparent space of the previous image.
if i remove the 'rotate' code, it draws just fine.

*slams head into desk*



Using mozilla firefox 2.0.0.2.

image i'm trying to use is located here:
http://www.hungates.com/images/thomas_track_6.png

any clues or hints to what's causing this?

---------------------Begin code clip------------------------
<HTML>
<HEAD>
<script type='text/javascript'>

function Track() {
   this.name = "";
   this.img = new Image();
   this.beginX1 = 0;
   this.beginY1 = 0;
   this.beginX2 = 0;
   this.beginY2 = 0;
   this.endX1 = 0;
   this.endY1 = 0;
   this.endX2 = 0;
   this.endY2 = 0;
   this.width = 0;
   this.height = 0;
   this.id = 0;
   this.numEnds = 2; // default to 2 end points, max of 4 end points.
minimum of 1 (bumper track)

   }
</script>
<script type='text/javascript'>

function init() {

var ctx = document.getElementById('canvas').getContext('2d');
     ctx.globalCompositeOperation = 'destination-over';

   track = new Track();
     track.img.src = "images/thomas_track_6.png";
     track.name = "6.5 in. Curve Track";
     track.beginX1 = 19;
     track.beginY1 = 122;
     track.endX1 = 74;
     track.endY1 = 8;
     track.width = 81;
     track.height = 132;

   ctx.clearRect(0,0,1000,625);
   ctx.save();
   ctx.translate(200,150);     // Set Initial Starting Point of Track

   ctx.drawImage(track.img,0,0, 81, 132);    // Draw 1st Curved Track Piece

   ctx.translate(73,8);        // move to track endpoint
       ctx.rotate(0.78525);    // 0.78525 (45 degrees in radians)
       ctx.drawImage(track.img,-19,-122, 81, 132);  // draw track with
offset, centered around startpoint

   ctx.restore();

   }
</script>
</HEAD>
<BODY onload='init()' style='margin: 0px; background-color: #eee;'>

<canvas id='canvas' width="1000px" height="625px"></canvas>

</BODY>
</HTML>
---------------------End code clip------------------------

#365 From: "Matthew Hagston" <matthew_hagston@...>
Date: Fri Mar 16, 2007 4:51 pm
Subject: Re: second image getting cut-off in firefox
matthew_hagston
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Note: if i tell it to draw twice, like this ...

   ctx.drawImage(track.img,-19,-122);      // draw track with offset,
centered around startpoint
   ctx.drawImage(track.img,-19,-122);      // draw track with offset,
centered around startpoint


... it draws correctly. Is this a bug or am i doing something wrong here?

--- In canvas-developers@yahoogroups.com, "Matthew Hagston"
<matthew_hagston@...> wrote:
>
> It's drawing the first piece of track just fine, but when i go to draw
> the second piece of track it only draws a small corner and doesn't
> draw the whole image.
>
> It seems to draw only in the transparent space of the previous image.
> if i remove the 'rotate' code, it draws just fine.
>
> *slams head into desk*
>
>
>
> Using mozilla firefox 2.0.0.2.
>
> image i'm trying to use is located here:
> http://www.hungates.com/images/thomas_track_6.png
>
> any clues or hints to what's causing this?
>
> ---------------------Begin code clip------------------------
> <HTML>
> <HEAD>
> <script type='text/javascript'>
>
> function Track() {
>   this.name = "";
>   this.img = new Image();
>   this.beginX1 = 0;
>   this.beginY1 = 0;
>   this.beginX2 = 0;
>   this.beginY2 = 0;
>   this.endX1 = 0;
>   this.endY1 = 0;
>   this.endX2 = 0;
>   this.endY2 = 0;
>   this.width = 0;
>   this.height = 0;
>   this.id = 0;
>   this.numEnds = 2; // default to 2 end points, max of 4 end points.
> minimum of 1 (bumper track)
>
>   }
> </script>
> <script type='text/javascript'>
>
> function init() {
>
> var ctx = document.getElementById('canvas').getContext('2d');
>     ctx.globalCompositeOperation = 'destination-over';
>
>   track = new Track();
>     track.img.src = "images/thomas_track_6.png";
>     track.name = "6.5 in. Curve Track";
>     track.beginX1 = 19;
>     track.beginY1 = 122;
>     track.endX1 = 74;
>     track.endY1 = 8;
>     track.width = 81;
>     track.height = 132;
>
>   ctx.clearRect(0,0,1000,625);
>   ctx.save();
>   ctx.translate(200,150);     // Set Initial Starting Point of Track
>
>   ctx.drawImage(track.img,0,0, 81, 132);    // Draw 1st Curved Track
Piece
>
>   ctx.translate(73,8);        // move to track endpoint
>       ctx.rotate(0.78525);    // 0.78525 (45 degrees in radians)
>       ctx.drawImage(track.img,-19,-122, 81, 132);  // draw track with
> offset, centered around startpoint
>
>   ctx.restore();
>
>   }
> </script>
> </HEAD>
> <BODY onload='init()' style='margin: 0px; background-color: #eee;'>
>
> <canvas id='canvas' width="1000px" height="625px"></canvas>
>
> </BODY>
> </HTML>
> ---------------------End code clip------------------------
>

#366 From: "mc_murlock" <mbonfils@...>
Date: Mon Mar 19, 2007 10:47 am
Subject: Speed with canvas
mc_murlock
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Hi,

I'm trying to use canvas with image (size 1000x800) (using XulRunner).
My aim is to allow user to select part of picture : highlighting the
selection, I'm redrawing canvas at each mouse event if a mouse button
is down.

The code is ok but not very fast (I'm using Windows XP, AMD 2200+),
I've tried the different value of globalCompositeOperation with no
success.

Have you got any tips ?

Thanks,
Michael


The code :

var ctx = canvas.getContext( '2d' );
ctx.globalCompositeOperation = "copy";
ctx.fillStyle = "rgb(0, 0, 0)";
// draw black border
ctx.fillRect( 0, 0, offset_x, canvas.height );
ctx.fillRect( offset_x, 0, canvas.width-offset_x, offset_y);
ctx.fillRect( canvas.width - offset_x, offset_y, offset_x,
canvas.height-offset_y );
ctx.fillRect( offset_x, canvas.height - offset_y, picture.width,
offset_y );

// draw image
ctx.drawImage( picture, offset_x, offset_y );

// hightlight the current selection :
ctx.globalCompositeOperation = "lighter";
ctx.fillStyle = "rgb(127,127,127)";
ctx.fillRect( x, y, w, h );
ctx.globalCompositeOperation = "copy";
ctx.strokeStyle = "rgb(255,165,0)";
ctx.strokeRect( x, y, w, h);

#367 From: "Mathieu HENRI" <p01@...>
Date: Mon Mar 19, 2007 11:32 am
Subject: Re: Speed with canvas
p01_opera
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FYI this can be done easily without Canvas, but since you ask on a
Canvas-related group, here is my take:

Why don't you simply set the image as the (CSS) background of the
Canvas tag, and only draw the colored overlay using Canvas ? it'd be
so much quicker and easier to implement.

#368 From: "Philip Taylor" <excors+yahoo@...>
Date: Tue Mar 20, 2007 10:53 pm
Subject: Re: Speed with canvas
excors_y
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On 19/03/07, mc_murlock <mbonfils@...> wrote:
> Hi,
>
> I'm trying to use canvas with image (size 1000x800) (using XulRunner).
> My aim is to allow user to select part of picture : highlighting the
> selection, I'm redrawing canvas at each mouse event if a mouse button
> is down.
>
> The code is ok but not very fast (I'm using Windows XP, AMD 2200+),
> I've tried the different value of globalCompositeOperation with no
> success.
>
> Have you got any tips ?

It would probably be useful to work out where the bottleneck is. If
you comment out the drawImage, does it go much faster? If you comment
out the highlighting fillRect/strokeRect, does it go much faster? Or
both equally?

If it's the drawImage that is slow, there's probably nothing you can
do directly to make it faster (other than being certain it's drawn
pixel-aligned, with no scaling or non-integer-pixel translation).
(Actually, that's not true if you're interested in performance in
Opera - at least in Opera 9 on Windows, I found it several times
faster if you load the image onto a new canvas once and then use
drawImage(canvas, ...) to copy it. But that's much slower in Firefox
(at least in old versions (1.5, 2.0?) on Windows, and maybe other ones
- I can't remember exactly now, but it's worth testing), so you have
to do some browser detection and switch between the two drawing
mechanisms. That was with scaled/translated images - I don't know if
the same applies to unscaled ones.)

Anyway, if that drawImage is slow, which doesn't seem unlikely if
you're copying 1000x800 pixels onto the screen buffer, I guess you'd
have to not do it. Maybe you can get away with only doing drawImage on
the section that was highlighted during the previous frame; or even
doing it only on the sections that were highlighted during the
previous frame and are no longer highlighted in the current one. It
adds some complexity and slowness in the JS code, and it gets a bit
expensive if you do lots of drawImage calls, but it may be worthwhile
if it saves you from copying hundreds of thousands of unchanged
pixels.

If the transparent highlighting is slow, and it's the transparency
that's slow (i.e. it's faster if you use 'copy' instead of 'lighter'),
perhaps you could pre-render a highlighted version of 'picture' and
then use a plain 'copy' drawImage to draw sections of the highlighted
one. (I suppose you'd hit the
drawing-from-canvas-is-slower-than-from-images-in-FF situation, if you
pre-render the lightened picture onto a canvas; maybe toDataURL could
help with that?)

Or you could wait for OpenGL acceleration :-)

> Thanks,
> Michael

--
Philip Taylor
excors@...

#369 From: "sean_imler" <simler@...>
Date: Wed Apr 4, 2007 1:03 am
Subject: stroke curves in excanvas
sean_imler
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Lines 505 and 506 of excanvas.js:
       // TODO: Following is broken for curves due to
       //       move to proper paths.

Has anyone come across this and know of a workaround or fix?

Thanks,
-sean

#370 From: "Andrew" <triptych@...>
Date: Wed Apr 4, 2007 5:21 pm
Subject: Apple is asserting it's IP rights over canvas - what does that mean for canvas?
triptych999
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http://lists.whatwg.org/pipermail/whatwg-whatwg.org/2007-March/010129.html

It looks like Apple is claiming IP rights over the canvas
specification. Does that mean that canvas is dead as an open spec?
What does this mean for the future of canvas and the WHAT group in
general?

#371 From: "brendaneich" <brendan@...>
Date: Wed Apr 4, 2007 6:57 pm
Subject: Re: Apple is asserting it's IP rights over canvas - what does that mean for canv
brendaneich
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--- In canvas-developers@yahoogroups.com, "Andrew" <triptych@...> wrote:
>
http://lists.whatwg.org/pipermail/whatwg-whatwg.org/2007-March/010129.html
>
> It looks like Apple is claiming IP rights over the canvas
> specification. Does that mean that canvas is dead as an open spec?

No, it means the WHATWG (I'm a founding member) is not a legal entity
and has no patent policy, so Apple must reserve its IP rights until
the spec lands in the w3c, or the WHATWG grows a patent policy.

> What does this mean for the future of canvas and the WHAT group in
> general?

The WHATWG was always intended to generate specs in an open,
lightweight fashion and standardize them with de-jure wrappings
elsewhere. The hope is that the newly-rechartered HTML working group
in the w3c will do just that, without making gratuitous changes or
adding delay.

Thanks to competitive and moral pressure from the WHATWG and others,
the w3c is using an open process for the HTML WG. You can join as an
individual member and participate. I encourage anyone on this list who
cares about <canvas> being standardized expeditiously to do so. See

http://www.w3.org/2000/09/dbwg/details?group=40318&public=1

and other links under

http://www.w3.org/html/wg/

/be

#372 From: "Andrew" <triptych@...>
Date: Wed May 16, 2007 1:59 pm
Subject: Canvas in IE8?
triptych999
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I wonder what the chances are for there being a canvas in IE8 - now
that the W3C is looking into HTML5.  What are folks here doing to
account for IE?  Is excanvas the de-facto standard now for canvas folks?

#373 From: "Jerason Banes" <jbanes@...>
Date: Wed May 16, 2007 3:14 pm
Subject: Re: Canvas in IE8?
thewiirocks
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Hi All!

This is my first post here after a long period of lurking, so apologies if my response has that "new poster" smell about it. ;-)

I have strong doubts about Microsoft implementing Canvas in IE8. For one thing, they don't recognize the WHATWG specifications as any sort of standard. For another, Microsoft has not kept up with the W3C standards; much less the "fast track" standards to improving the web. I'd be happy just to get DOM 2 and SVG support.

While excanvas is a workable solution, its performance leaves something to be desired. Considering that one of the primary uses of Canvas is to create web-enabled animations and video games, it seems that a better solution is in order.

One of the solutions I've been considering is to use a Java Applet or Flash component to simulate the 2D context. Either option should provide significantly better performance than the VML approach of excanvas. The straightforward nature of LiveConnect + support for hardware acceleration makes Java the preferred option. However, I believe that scripting of Flash components is also supported in IE. This makes Flash a viable alternative to the Java solution. Which is important given that Flash has greater market penetration.

The only problem with these solutions is that they won't be able to implement the spec 100%. In specific, the issue is that these embedded technologies tend to obscure the background HTML. This makes it difficult (impossible?) to have transparent canvases, reducing the effectiveness of the solution for certain classes of web animations. (Thankfully, this is not an issue for most games.) Java also has difficulties with proper handling of proxies, and would need to perform a second load on any image to be drawn by the Canvas.

Still, I think this is an option worth exploring. If I manage to find the time in the future, I will dig deeper to see what is possible.

Thanks,
Jerason Banes

I wonder what the chances are for there being a canvas in IE8 - now
that the W3C is looking into HTML5.  What are folks here doing to
account for IE?  Is excanvas the de-facto standard now for canvas folks?


#374 From: Vladimir Vukicevic <vladimir@...>
Date: Wed May 16, 2007 5:40 pm
Subject: Re: Canvas in IE8?
vvukicevic
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Howdy,

I agree with Jerason -- I wouldn't hold my breath for canvas (or really,
any WHATWG or any modern-web specs) in IE8.  Microsoft seems to be
pushing the all-singing and all-dancing Silverlight, and so the status
quo of ignoring the web seems to continue.

I'm no big fan of Flash, but building a canvas shim using Flash seems
like a fantastic idea -- note that the only relevant platform is IE on
Windows, so Flash works fine in so-called windowless mode... in this
case it can integrate into the surrounding page HTML like native canvas
can (transparent backgrounds, overlaid elements, etc).  It would be an
interesting experiment for sure.

     - Vlad

Jerason Banes wrote:
> Hi All!
>
> This is my first post here after a long period of lurking, so apologies
> if my response has that "new poster" smell about it. ;-)
>
> I have strong doubts about Microsoft implementing Canvas in IE8. For one
> thing, they don't recognize the WHATWG specifications as any sort of
> standard. For another, Microsoft has not kept up with the W3C standards;
> much less the "fast track" standards to improving the web. I'd be happy
> just to get DOM 2 and SVG support.
>
> While excanvas is a workable solution, its performance leaves something
> to be desired. Considering that one of the primary uses of Canvas is to
> create web-enabled animations and video games, it seems that a better
> solution is in order.
>
> One of the solutions I've been considering is to use a Java Applet or
> Flash component to simulate the 2D context. Either option should provide
> significantly better performance than the VML approach of excanvas. The
> straightforward nature of LiveConnect + support for hardware
> acceleration makes Java the preferred option. However, I believe that
> scripting of Flash components is also supported in IE. This makes Flash
> a viable alternative to the Java solution. Which is important given that
> Flash has greater market penetration.
>
> The only problem with these solutions is that they won't be able to
> implement the spec 100%. In specific, the issue is that these embedded
> technologies tend to obscure the background HTML. This makes it
> difficult (impossible?) to have transparent canvases, reducing the
> effectiveness of the solution for certain classes of web animations.
> (Thankfully, this is not an issue for most games.) Java also has
> difficulties with proper handling of proxies, and would need to perform
> a second load on any image to be drawn by the Canvas.
>
> Still, I think this is an option worth exploring. If I manage to find
> the time in the future, I will dig deeper to see what is possible.
>
> Thanks,
> Jerason Banes
>
>     I wonder what the chances are for there being a canvas in IE8 - now
>     that the W3C is looking into HTML5.  What are folks here doing to
>     account for IE?  Is excanvas the de-facto standard now for canvas
>     folks?
>
>
>

#375 From: Seldo V <seld0@...>
Date: Thu May 17, 2007 6:03 am
Subject: Re: Canvas in IE8?
laurie.voss
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Flash is certainly an interesting possibility for canvas support in IE -- I don't think Java would be; its performance in a browser has always been suspect.

L.

----- Original Message ----
From: Vladimir Vukicevic <vladimir@...>
To: canvas-developers@yahoogroups.com
Sent: Wednesday, May 16, 2007 10:40:00 AM
Subject: Re: [canvas-developers] Canvas in IE8?

Howdy,

I agree with Jerason -- I wouldn't hold my breath for canvas (or really,
any WHATWG or any modern-web specs) in IE8. Microsoft seems to be
pushing the all-singing and all-dancing Silverlight, and so the status
quo of ignoring the web seems to continue.

I'm no big fan of Flash, but building a canvas shim using Flash seems
like a fantastic idea -- note that the only relevant platform is IE on
Windows, so Flash works fine in so-called windowless mode... in this
case it can integrate into the surrounding page HTML like native canvas
can (transparent backgrounds, overlaid elements, etc). It would be an
interesting experiment for sure.

- Vlad

Jerason Banes wrote:
> Hi All!
>
> This is my first post here after a long period of lurking, so apologies
> if my response has that "new poster" smell about it. ;-)
>
> I have strong doubts about Microsoft implementing Canvas in IE8. For one
> thing, they don't recognize the WHATWG specifications as any sort of
> standard. For another, Microsoft has not kept up with the W3C standards;
> much less the "fast track" standards to improving the web. I'd be happy
> just to get DOM 2 and SVG support.
>
> While excanvas is a workable solution, its performance leaves something
> to be desired. Considering that one of the primary uses of Canvas is to
> create web-enabled animations and video games, it seems that a better
> solution is in order.
>
> One of the solutions I've been considering is to use a Java Applet or
> Flash component to simulate the 2D context. Either option should provide
> significantly better performance than the VML approach of excanvas. The
> straightforward nature of LiveConnect + support for hardware
> acceleration makes Java the preferred option. However, I believe that
> scripting of Flash components is also supported in IE. This makes Flash
> a viable alternative to the Java solution. Which is important given that
> Flash has greater market penetration.
>
> The only problem with these solutions is that they won't be able to
> implement the spec 100%. In specific, the issue is that these embedded
> technologies tend to obscure the background HTML. This makes it
> difficult (impossible? ) to have transparent canvases, reducing the
> effectiveness of the solution for certain classes of web animations.
> (Thankfully, this is not an issue for most games.) Java also has
> difficulties with proper handling of proxies, and would need to perform
> a second load on any image to be drawn by the Canvas.
>
> Still, I think this is an option worth exploring. If I manage to find
> the time in the future, I will dig deeper to see what is possible.
>
> Thanks,
> Jerason Banes
>
> I wonder what the chances are for there being a canvas in IE8 - now
> that the W3C is looking into HTML5. What are folks here doing to
> account for IE? Is excanvas the de-facto standard now for canvas
> folks?
>
>
>




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#376 From: "Jerason Banes" <jbanes@...>
Date: Thu May 17, 2007 3:28 pm
Subject: Re: Canvas in IE8?
thewiirocks
Send Email Send Email
 
If you're referring to the time it takes to load the JVM, then I agree that there is an issue. A Java-based canvas is therefore more useful when the Canvas in question is central to the webpage. (e.g. A video game.) The graphical performance possible with Java makes it an ideal choice in such a situation simply because Java VMs of versions 1.4 or greater provide direct hardware acceleration of 2D graphics. Therefore, you're going to see much higher framerates in animations and games than a Flash component could offer.

It is also possible to simulate the moz-gles11 plugin by using a signed Java Applet to deploy JOGL. This is not possible in Flash.

Flash is ideal if you're attempting to create a more generic replacement for Canvas. Windowless mode sounds like an excellent solution (thanks for the suggestion, Vlad!), but the performance isn't going to be as good as what is possible with Java. Also, (and feel free to correct me if I'm wrong) Flash 8 or higher is required to implement the Canvas because earlier versions did not have an actual drawing surface. You could fake it by dynamically creating objects, but then you are back to the performance issues of VML/SVG.

This being Internet Explorer on Windows, though, requiring Flash 8 shouldn't be a problem. :)

Thanks,
Jerason

On 5/17/07, Seldo V <seld0@...> wrote:

Flash is certainly an interesting possibility for canvas support in IE -- I don't think Java would be; its performance in a browser has always been suspect.


#377 From: "Andrew" <triptych@...>
Date: Fri May 18, 2007 4:52 pm
Subject: Re: Canvas in IE8?
triptych999
Send Email Send Email
 
I for one would love to contribute to building a canvas implementation
in Flash. I first wonder if anyone is already working on a project
like this and second wonder if folks would like to begin a FlashCanvas
implementation.

An exciting idea beyond this (if it gets off the ground ) - imagine
when work starts on the 3D canvas context. Papervision 3D meets 3D
canvas -- cool.



--- In canvas-developers@yahoogroups.com, "Jerason Banes" <jbanes@...>
wrote:
>
> If you're referring to the time it takes to load the JVM, then I
agree that
> there is an issue. A Java-based canvas is therefore more useful when the
> Canvas in question is central to the webpage. (e.g. A video game.) The
> graphical performance possible with Java makes it an ideal choice in
such a
> situation simply because Java VMs of versions 1.4 or greater provide
direct
> hardware acceleration of 2D graphics. Therefore, you're going to see
much
> higher framerates in animations and games than a Flash component could
> offer.
>
> It is also possible to simulate the moz-gles11 plugin by using a
signed Java
> Applet to deploy JOGL. This is not possible in Flash.
>
> Flash is ideal if you're attempting to create a more generic
replacement for
> Canvas. Windowless mode sounds like an excellent solution (thanks
for the
> suggestion, Vlad!), but the performance isn't going to be as good as
what is
> possible with Java. Also, (and feel free to correct me if I'm wrong)
Flash 8
> or higher is required to implement the Canvas because earlier
versions did
> not have an actual drawing surface. You could fake it by dynamically
> creating objects, but then you are back to the performance issues of
> VML/SVG.
>
> This being Internet Explorer on Windows, though, requiring Flash 8
shouldn't
> be a problem. :)
>
> Thanks,
> Jerason
>
> On 5/17/07, Seldo V <seld0@...> wrote:
> >
> >   Flash is certainly an interesting possibility for canvas support
in IE
> > -- I don't think Java would be; its performance in a browser has
always been
> > suspect.
> >
>

#378 From: Stefan Haustein <mail@...>
Date: Sat May 19, 2007 1:15 am
Subject: Re: Re: Canvas in IE8?
dukoids
Send Email Send Email
 
Hi,

I have started working on a Java version (rhinocanvas.sf.net), but I
agree that for the browser flash probably makes more sense (installed
base, startup time,...). I would love to see more efficient canvas
support in IE.

Best regards
Stefan Haustein

Andrew wrote:
> I for one would love to contribute to building a canvas implementation
> in Flash. I first wonder if anyone is already working on a project
> like this and second wonder if folks would like to begin a FlashCanvas
> implementation.
>
> An exciting idea beyond this (if it gets off the ground ) - imagine
> when work starts on the 3D canvas context. Papervision 3D meets 3D
> canvas -- cool.
>
>
>
> --- In canvas-developers@yahoogroups.com, "Jerason Banes" <jbanes@...>
> wrote:
>
>> If you're referring to the time it takes to load the JVM, then I
>>
> agree that
>
>> there is an issue. A Java-based canvas is therefore more useful when the
>> Canvas in question is central to the webpage. (e.g. A video game.) The
>> graphical performance possible with Java makes it an ideal choice in
>>
> such a
>
>> situation simply because Java VMs of versions 1.4 or greater provide
>>
> direct
>
>> hardware acceleration of 2D graphics. Therefore, you're going to see
>>
> much
>
>> higher framerates in animations and games than a Flash component could
>> offer.
>>
>> It is also possible to simulate the moz-gles11 plugin by using a
>>
> signed Java
>
>> Applet to deploy JOGL. This is not possible in Flash.
>>
>> Flash is ideal if you're attempting to create a more generic
>>
> replacement for
>
>> Canvas. Windowless mode sounds like an excellent solution (thanks
>>
> for the
>
>> suggestion, Vlad!), but the performance isn't going to be as good as
>>
> what is
>
>> possible with Java. Also, (and feel free to correct me if I'm wrong)
>>
> Flash 8
>
>> or higher is required to implement the Canvas because earlier
>>
> versions did
>
>> not have an actual drawing surface. You could fake it by dynamically
>> creating objects, but then you are back to the performance issues of
>> VML/SVG.
>>
>> This being Internet Explorer on Windows, though, requiring Flash 8
>>
> shouldn't
>
>> be a problem. :)
>>
>> Thanks,
>> Jerason
>>
>> On 5/17/07, Seldo V <seld0@...> wrote:
>>
>>>   Flash is certainly an interesting possibility for canvas support
>>>
> in IE
>
>>> -- I don't think Java would be; its performance in a browser has
>>>
> always been
>
>>> suspect.
>>>
>>>
>
>
>
>
>
> Yahoo! Groups Links
>
>
>
>

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