The conversion to / from RGB and YCbCr look OK, but what you do to
derive a new color is not. It will work for gray-scale colors, but if
you deviate from gray it will drastically change the color, even
generating out of range values if one component is small and another is
large.
Here are some examples in YCbCr space :
orig color: 100, 50, 0
derived color: 112, 194, 99 (too green)
orig color: 55, 0, 225
derived color: 286, 32, 324 (out of range)
I think it will be better to convert to something like HSV (aka HSB) and
do the lightening or darkening in that space. I tried a quick test
program using JavaFX, which has built-in RGB <--> HSB conversion and
that works as I would expect.
Here are the same examples in HSB space:
orig color: 100, 50, 0
derived color: 200, 100, 0
orig color: 55, 0, 225
derived color: 31, 0, 125
-- Kevin
On 8/1/2019 2:50 PM, Philip Race wrote:
The if/else looks OK now.
But can you point to the exact the source you used for the formulas
for RGB->YCbCr
conversion and the conversion back from YCbCr to RGB ?
Kevin & I were trying to figure it out and then Kevin wrote some test
programs to see how round tripping works and found some significant
problems.
I'll let Kevin reply with his findings.
-phil.
On 8/1/19, 11:58 AM, Pankaj Bansal wrote:
Hello Phil,
<< So why can't we simplify it to this ?
I was trying something similar, but your method looks much simpler to
understand. I have used it.
I think in line2, instead of
if (highlightLuminance + minLuminanceDifference <= maxLuminance) {
you meant this. Rest I have used as such.
if (backgroundLuminance + minLuminanceDifference <= maxLuminance) {
<<1) can we avoid "if(" and include a space as in "if (" >
<<2) There are some lines much > 80 chars.
Fixed
webrev: http://cr.openjdk.java.net/~pbansal/8226964/webrev02/
<http://cr.openjdk.java.net/%7Epbansal/8226964/webrev02/>
Regards,
Pankaj
*From:*Philip Race
*Sent:* Thursday, August 1, 2019 10:24 PM
*To:* Pankaj Bansal
*Cc:* [email protected]
*Subject:* Re: <Swing Dev> [13] RFR JDK-8226964 [Yaru] - GTK L&F:
There is no difference between menu selected and de-selected
I am not sure about the logic in the if/else blocks.
The way it is structured and the way the conditions are expressed
aren't making it easy for me to follow, or perhaps I am just failing
to understand some subtle requirements.
And why do you do this ?
+ highlightLuminance += minLuminanceDifference;
Suppose that the highLight luminance difference was already "99",
why do you need to add another "100" to it ?
It seems to me that once we are in the block where we've decided that
the difference is < 100, the goal of every assignment has to be to
make sure the highlight is exactly either 100 brighter or 100 darker
than the
background, isn't it ?
So why can't we simplify it to this ?
if (highlightLuminance >= backgroundLuminance) {
if (highlightLuminance +
minLuminanceDifference <= maxLuminance) {
highlightLuminance = backgroundLuminance +
minLuminanceDifference;
} else {
highlightLuminance = backgroundLuminance
- minLuminanceDifference;
}
} else {
if (backgroundLuminance -
minLuminanceDifference >= minLuminance) {
highlightLuminance = backgroundLuminance
- minLuminanceDifference;
} else {
highlightLuminance = backgroundLuminance
+ minLuminanceDifference;
}
}
Two nits
1) can we avoid "if(" and include a space as in "if (" >
2) There are some lines much > 80 chars.
-phil
On 8/1/19, 1:58 AM, Pankaj Bansal wrote:
Hi Phil,
<< nit pick : you spelled luminance wrong here :
<<int actualLuminaceDifference
Corrected
<< Some of the variable naming is confusing me.
<< So until I get clarity on the intent here I can't verify the
correctness of
the logic that follows although I understand your intent as being
to make
the highlight lighter so long as it is already lighter than the
background and
you don't have to exceed max luminance to do it, and if that
won't work make
the highlight darker instead. And so forth for the other cases.
Yes, this is exactly what I am doing. I understand your point
about naming. Once I have defined what is highlight and what is
background, I should just use these for naming instead of menubar
and menuitem. I have corrected the naming of variables used.
webrev: http://cr.openjdk.java.net/~pbansal/8226964/webrev01/
<http://cr.openjdk.java.net/%7Epbansal/8226964/webrev01/>
Regards,
Pankaj
*From:*Philip Race
*Sent:* Thursday, August 1, 2019 6:16 AM
*To:* Pankaj Bansal
*Cc:* [email protected] <mailto:[email protected]>
*Subject:* Re: <Swing Dev> [13] RFR JDK-8226964 [Yaru] - GTK L&F:
There is no difference between menu selected and de-selected
nit pick : you spelled luminance wrong here :
int actualLuminaceDifference
Some of the variable naming is confusing me.
Color highlightColor = style.getGTKColor(
+ GTKEngine.WidgetType.MENU_ITEM.ordinal(),
ok so Highlight comes from MENU_ITEM
and background comes from MENU_BAR :
+ Color backgroundColor = style.getGTKColor(
+ GTKEngine.WidgetType.MENU_BAR.ordinal(),
but then we assign menubar luminance from highlight which was got
from menu item
and menu item luminance from background which was got from menu bar
double menubarLuminance = getY(highlightColor.getRed(),
+ highlightColor.getGreen(),
highlightColor.getBlue());
+ double menuitemLuminance =
getY(backgroundColor.getRed(),
+ backgroundColor.getGreen(),
backgroundColor.getBlue());
Can you explain this ? Or is it wrong ?
I get further confused when I read ..
+ // when the highlight has more luminance and
it's luminance
+ // can be increased further by
minLuminanceDifference
+ if ((menubarLuminance < menuitemLuminance) &&
.. so menuItemLuminance is greater implying it is the highlight
but we derived
it from the background.
So until I get clarity on the intent here I can't verify the
correctness of
the logic that follows although I understand your intent as being
to make
the highlight lighter so long as it is already lighter than the
background and
you don't have to exceed max luminance to do it, and if that
won't work make
the highlight darker instead. And so forth for the other cases.
-phil.
On 7/31/19, 3:16 PM, Pankaj Bansal wrote:
Hi All,
Please review the following fix for jdk13.
Bug:
https://bugs.openjdk.java.net/browse/JDK-8226964
webrev
http://cr.openjdk.java.net/~pbansal/8226964/webrev00/
<http://cr.openjdk.java.net/%7Epbansal/8226964/webrev00/>
Issue:
The menu is not getting highlighted on being selected.
The issue is only reproducible on Yaru theme as the menu
highlight color used by java is very similar to the
background color of menubar. So the highlight is not properly
visible due to poor contrast.
Fix:
The fix checks that if the background menubar color and
highlight color are very close, make the highlight more
darker or lighter, so that it is clearly visible.
Testing:
The fix can be verified by running SwingSet2. I have verified
this on Ubuntu 16.04, 18.04, 19.04 and OEL 7.5.
Regards,
Pankaj Bansal
