Re: [Gnash-commit] gnash ChangeLog gui/fb.cpp gui/fbsup.h gui/gui....

[Udo Giacomozzi]

Hello Udo,

Thursday, October 12, 2006, 6:37:26 PM, you wrote:

UG> CVSROOT:        /cvsroot/gnash
UG> Module name:    gnash
UG> Changes by:     Udo Giacomozzi <udog>   06/10/12 16:37:25

Whew, a few notes on this commit:

This does now allow to determine which parts of the stage have been
updated (moving, adding/removing, transforming characters, changing
text variables etc.). This has two advantages:

1st, it allows a renderer/gui combination to avoid re-rendering of
unchanged parts in the scene. Currently only FBGui uses this but I
plan to rewrite the AGG renderer to respect this region, too. It
should be a huge performance increase in certain cases.

2nd, it can detect still frames (like a stopped movie). gui.cpp can
detect these and completely avoids to call any rendering function.

There is a #if 0 in gui.cpp that, when activated, shows the changed
region with a red frame (the Flash player has the same option).

Of course, the most critical part is detection of changes. I
introduced a method called set_invalidated() which gets called
whenever a change is obvious (like adding/removing a character). I
tested this really carefully and hope I did not miss anything. Anyway,
it's really important to always call set_invalidated() whenever code
is added that changed the character instance in a visible way.

Even if no renderer really uses this information it has effects when
skipping unchanged frames. If necessary, this feature can be switched
off easily in gui.cpp (maybe using a runtime option?).

As for the integer/float discussion: I used rect (floats) because all
the bounds calculation involves floats anyway and so it's probably
faster than converting between ints and floats all the way.


That's all so far,
Udo