Wayland - Beyond X (The H)

Posted Feb 14, 2012 21:53 UTC (Tue) by aliguori (subscriber, #30636)
In reply to: Wayland - Beyond X (The H) by nix
Parent article: Wayland - Beyond X (The H)

>The framebuffer changes constantly, but when textual output is being displayed it normally changes to display the same bits of stuff over and over again (or the same bits of stuff over and over again, alpha-composited onto a constant background or a constant background pixmap). If the remoting model used by VNC represented this properly, it would be very low-bandwidth indeed.

It doesn't. All modern tool kits do their own font rendering (this is what Pango provides).

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Wayland - Beyond X (The H)

Posted Feb 14, 2012 22:59 UTC (Tue) by nix (subscriber, #2304) [Link] (1 responses)

Yeah. They do their own font rendering, rendering to glyphs which are then sent to X as a GlyphSet, right?

Wayland - Beyond X (The H)

Posted Feb 16, 2012 0:05 UTC (Thu) by aliguori (subscriber, #30636) [Link]

Oh, I was not aware of the GlyphSets extension. VNC only has a very simple bitmap based protocol that can provide updates to the bitmap at a rectangle granularity.

It has no concept of offscreen bitmaps, alpha blending, or anything like that.