On Feb 14, 2011, at 8:51 50PM, laurent laffont wrote:
On Mon, Feb 14, 2011 at 7:57 PM, Igor Stasenko
<siguctua@gmail.com> wrote:
On 14 February 2011 18:45, laurent laffont <laurent.laffont@gmail.com> wrote:
> Today: ColorMappingCanvas
>
As far as i understood, this class is abstract, and its subclasses
implement more specific behavior
- shadow
- semitransparency mapping
The idea of is kind of canvas is to modify/filter the final output in
rendering pipe..
i.e., for each potential pixel operation like:
source -> op -> output
it introducing a color mapping stage:
source -> op -> mapping -> output
So, then for instance you could make a subclass which could turn all
colors to be grayscale (disregarding that initial input was in
colors).
in fact i think this guy took wrong direction. It is much more
effective to let the canvas to draw whatever it wants to some
backup/temporary surface, and once it done, simply blit + color-map
result to destination form using one, single strike.
ah ah, it seems last COTDC are:
- this class is bad written
- this is not used
- nobody understand
still lot of work ;)
Laurent
ShadowCanvas is used in the Glamour theme when fastDragForMorphic is disabled.
Cheers,
Henry
PS. You'll see a noticable increase in dragging performance (at least on non-Cog vms)if you change configureWindowBorderFor: to return a non-translucent value.
This is because wantsToBeCachedByHand returns false when the morph isTranslucent.
I don't really think the restriction makes much sense, a canvas should have no problem drawing a cached image with translucency, but changing it probably includes revisiting how paint rules are chosen, which will be a huge pain for whoever does it.