- From: Rik Cabanier <cabanier@gmail.com>
- Date: Fri, 13 Apr 2012 10:16:38 -0700
On Fri, Apr 13, 2012 at 2:17 AM, Ashley Gullen <ashley at scirra.com> wrote: > This looks very handy for games as well! Things like 'screen' work very > nicely for some effects, especially explosions. Yes, these effects are very commonly used in games, animation and artwork. > > Surely you'd want to extend the existing list of globalCompositeOperation > though? > That seemed the easiest way to go. I can see some edge cases that you wouldn't be able to implement easy (ie do a src-out with a screen). I think it would still be possible to do but it would take an extra step. > Otherwise you'd have to define how globalCompositeOperation and > globalBlendOperation interact. > > My spec is trying to define how they interact. Basically, blending is done first and replaces the original source. This new source is then composited. Thanks for the feedback! Rik > > On 12 April 2012 00:39, Rik Cabanier <cabanier at gmail.com> wrote: > >> :-) >> They are definitely more familiar to designers but they both have their >> place. >> >> On Wed, Apr 11, 2012 at 4:30 PM, Jeremy Apthorp <jeremya at chromium.org >> >wrote: >> >> > On Wed, Apr 11, 2012 at 4:05 PM, Rik Cabanier <cabanier at gmail.com> >> wrote: >> > >> >> All, >> >> >> >> I'm working on a spec to add blending and compositing through simple >> CSS >> >> keywords. It is trying to define a generic model that is not specific >> to >> >> Canvas, HTML or SVG and then lists how the model could be implemented. >> >> We've gotten some comments that this feature would be useful in Canvas >> as >> >> well so I was wondering if it made sense to add it to the canvas API. >> >> >> >> I can see 2 ways of adding this: >> >> 1. extend the list of compositing operators ( >> >> >> >> >> http://www.whatwg.org/specs/web-apps/current-work/multipage/the-canvas-element.html#compositing >> >> ) >> >> with blending. This is what is currently in the draft spec ( >> >> https://dvcs.w3.org/hg/FXTF/rawfile/tip/compositing/index.htmlchapter 7) >> >> >> >> 2. create a new attribute on the context called 'globalBlendOperation' >> >> that >> >> takes the same list of blend operations as css ( >> >> >> https://dvcs.w3.org/hg/FXTF/rawfile/tip/compositing/index.html#blend-mode >> >> ) >> >> >> >> Any thoughts? >> >> >> > >> > This seems much more useful than the existing composite operations :) >> > >> > >
Received on Friday, 13 April 2012 10:16:38 UTC