[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Public WebGL] Behavior of WebGL canvas when it can't make a backbuffer of the requested size?

On 06/11/2010 01:28, Chris Marrin wrote:
> The last question is whether or not there is a call that will tell the author the maximum dimensions of the drawing buffer. There is MAX_VIEWPORT_DIMS which will probably give the right answer. But I don't think there is any guarantee that the window system maximums are reflected in MAX_VIEWPORT_DIMS. So we should either clarify that this value will always give the right answer or create a new call to give the max dimensions.
The OpenGL ES 2.0 spec. says "The maximum viewport dimensions must be
greater than or equal to the visible dimensions of the display being
rendered to." so the window system maximums are supposed to be reflected
in this MAX_VIEWPORT_DIMS. However it does not seem relevant in this
case as the browsers are not using window surfaces. They are using FBOs.

If the browser is rendering into a renderbuffer, then
MAX_RENDERBUFFER_SIZE will govern. The minimum requirement is only 1x1.
If its rendering to a texture then MAX_TEXTURE_SIZE will govern. It's
minimum requirement is 64x64.


fn:Mark Callow
org:HI Corporation;Graphics Lab, Research & Development
adr:Higashiyama 1-4-4, Meguro-ku;;Meguro Higashiyama Bldg 5F;Tokyo;;153-0043;Japan
title:Chief Architect
tel;work:+81 3 3710 9367 x228
tel;fax:+81 3 5773 8660
url:http://www.hicorp.co.jp,  http://www.mascotcapsule.com