- From: Michael Foster <foster@PacketVideo.COM>
- Date: Thu, 19 Jun 2003 09:40:32 -0700
- To: "'www-smil@w3.org'" <www-smil@w3.org>
I tried to post this message on May 30. Not sure if it got through (did not receive any responses). Here it is again ............................................................................ .. Hi everyone, I have a couple of questions about the rendering order of region backgrounds. I have searched the newsgroup archives and SMIL spec, but can't find any discussion of these issues. Here is the first question. In the following SMIL file, all regions have the same z-index. Two media elements share the same region ('full'). At t=8s, according to the z-index processing described in the spec, 'img1' will be rendered first, followed by 'img2' and then 'img3'. The question is when will the background of region 'full' be rendered? Will it be rendered before rendering 'img1' and then again before rendering 'img3'? If so, no portion of 'img1' would be visible if 'img3' were smaller than 'img1'. Or will it be rendered only once before either 'img1' or 'img3' is rendered? If it were only rendered before 'img1', then 'img3' could be rendered on top of 'img2' without its background. ...................................... <smil> <head> <layout> <root-layout width="100" height="100" z-index="1" background-color="#000000" /> <region id="full" top="0%" left="0%" width="100%" height="100%" z-index="1" background-color="#0000FF" /> <region id="top_right" top="0%" left="50%" width="50%" height="50%" z-index="1" background-color="#FF0000" /> </layout> </head> <body> <par dur="10s"> <img id="img1" begin="0s" region="full" type="image/gif" src="img1.gif" /> <img id="img2" begin="4s" region="top_right" type="image/gif" src="img2.gif" /> <img id="img3" begin="6s" region="full" type="image/gif" src="img3.gif" /> </par> </body> </smil> ...................................... Here is the second question. In the following SMIL file, all regions have the same z-index. Region 'top_right' does not have any media elements associated with it, however since the default value of the showBackground attribute is always, this region background will be rendered. At t=6s, according to the z-index processing described in the spec, 'img1' will be rendered first, followed by 'img2'. The question is when will the background of region 'top_right' be rendered? The z-index processing described in the spec cannot be used to determine the rendering order for this region background because there is no media element associated with it. ...................................... <smil> <head> <layout> <root-layout width="100" height="100" z-index="1" background-color="#000000" /> <region id="full" top="0%" left="0%" width="100%" height="100%" z-index="1" background-color="#0000FF" /> <region id="top_right" top="0%" left="50%" width="50%" height="50%" z-index="1" background-color="#FF0000" /> </layout> </head> <body> <par dur="10s"> <img id="img1" begin="0s" region="full" type="image/gif" src="img1.gif" /> <img id="img2" begin="4s" region="full" type="image/gif" src="img2.gif" /> </par> </body> </smil> ...................................... Thanks for any help you can provide Mike _________________________________________________ Michael Foster * PacketVideo * (858) 731-5543 Senior Member of Technical Staff foster@pv.com * www.packetvideo.com
Received on Thursday, 19 June 2003 12:40:47 UTC