<Swing Dev> [9] Review request for 8156217 Selected text is shifted on HiDPI display
Alexandr Scherbatiy
alexandr.scherbatiy at oracle.com
Mon Sep 12 12:19:44 UTC 2016
Hello,
Could you review the updated fix:
all changes: http://cr.openjdk.java.net/~alexsch/8156217/webrev.07/all
public API changes:
http://cr.openjdk.java.net/~alexsch/8156217/webrev.07/public-api
- @since 9 tag is added to new methods.
Thanks,
Alexandr.
On 9/10/2016 2:36 AM, Philip Race wrote:
> - * Returns the tab size set for the document, defaulting to 8.
> - *
> - * @implSpec This implementation calls {@link #getTabSize()
> getTabSize()}.
> - *
> - * @return the tab size
> - */
> - protected float getFractionalTabSize() {
> - return getTabSize();
> - }
> -
>
>
> It seems this was added only in 9.
> Since I think I remember that asking a question about it.
> I note it has no @since. Moot if you are really removing it but
> what has it to do with the rest of this change ?
>
> -phil.
>
> On 9/9/16, 11:51 AM, Alexandr Scherbatiy wrote:
>>
>> Hello,
>>
>> Could you review the updated fix:
>> all changes: http://cr.openjdk.java.net/~alexsch/8156217/webrev.06/all
>> public API changes:
>> http://cr.openjdk.java.net/~alexsch/8156217/webrev.06/public-api
>>
>> - reflection is used to detect do methods with floating point API
>> need to be called.
>>
>> Thanks,
>> Alexandr.
>>
>> On 9/1/2016 9:17 PM, Semyon Sadetsky wrote:
>>>
>>>
>>>
>>> On 9/1/2016 8:26 PM, Alexandr Scherbatiy wrote:
>>>> On 9/1/2016 7:27 PM, Alexandr Scherbatiy wrote:
>>>>> On 9/1/2016 6:49 PM, Semyon Sadetsky wrote:
>>>>>>
>>>>>> Alexander, did you consider possibility to check if method is
>>>>>> really over-riden then to use the old API?
>>>>>>
>>>>> Could you give a sample how it can be done?
>>>> I think it is possible to use a reflection to found the latest
>>>> overridden method which uses int coordinates and check does it has
>>>> a corresponding overridden method with floating point arguments.
>>>> But I doubt that it is a good solution.
>>> yes. You could use:
>>> useFloatingPointAPI =
>>> PlainView.class.equals(getClass().getMethod("drawUnselectedText",
>>> ...).getDeclaringClass());
>>>
>>> Otherwise, with high probability your new API will never be used.
>>>
>>> --Semyon
>>>>
>>>> Thanks,
>>>> Alexandr.
>>>>>
>>>>> Thanks,
>>>>> Alexandr.
>>>>>
>>>>>> --Semyon
>>>>>>
>>>>>> On 9/1/2016 3:07 PM, Alexandr Scherbatiy wrote:
>>>>>>> On 9/1/2016 11:31 AM, Semyon Sadetsky wrote:
>>>>>>>>
>>>>>>>> Hi Alexander,
>>>>>>>>
>>>>>>>> It is a good style to add a note recommending what to use
>>>>>>>> instead of the method which is being deprecated.
>>>>>>>>
>>>>>>> Could you review the updated public API there "replaced by"
>>>>>>> notes are added to the deprecated methods:
>>>>>>> http://cr.openjdk.java.net/~alexsch/8156217/webrev.05/public-api.02
>>>>>>>>
>>>>>>>> I did not get for what the useFloatingPointAPI property was
>>>>>>>> introduced and moreover is set to false by default. If the old
>>>>>>>> API is used then it doesn't matter which value it has because
>>>>>>>> the float values will receive ints. And for the new API I would
>>>>>>>> expect everything having the float precision, and it is unclear
>>>>>>>> what may be the reason to switch it off back to integer.
>>>>>>>> Especially if
>>>>>>>>
>>>>>>>> " This allows to draw text properly using graphics with scaled
>>>>>>>> transform."
>>>>>>>>
>>>>>>>> so an improper mode is the default?
>>>>>>>>
>>>>>>> This is has been discussed below. For example new
>>>>>>> drawSelectedText(Graphics2D g, float x, float y, int p0, int p1)
>>>>>>> with floating point coordinates is added to the PlainView which
>>>>>>> has the same method with int coordinates. Suppose someone has a
>>>>>>> custom password component which uses and old methods with int
>>>>>>> coordinates.
>>>>>>> --------
>>>>>>> public class CustomPasswordField extends FieldView {
>>>>>>>
>>>>>>> @Override
>>>>>>> protected int drawSelectedText(Graphics g, int x, int y,
>>>>>>> int p0, int p1) throws BadLocationException {
>>>>>>> // draw echo chars
>>>>>>> }
>>>>>>> }
>>>>>>> --------
>>>>>>>
>>>>>>> If we start to call drawSelectedText() with floating point
>>>>>>> values the customization of old components will not be used and
>>>>>>> the CustomPasswordField from the example starts to show real
>>>>>>> text instead of echo chars. This is incompatible change with
>>>>>>> previous JDK releases.
>>>>>>>
>>>>>>> The solution is to switch to new floating point API only when it
>>>>>>> is known that a component properly overrides new methods with
>>>>>>> floating point arguments. After that the
>>>>>>> PlainView.useFloatingPointAPI flag can be set to true.
>>>>>>>
>>>>>>> For example, BasicPasswordFieldUI sets the
>>>>>>> PasswordView.useFloatingPointAPI flag to true because it is
>>>>>>> sure that drawSelectedText() methods with floating point
>>>>>>> arguments is overridden. So Swing standard text components are
>>>>>>> switched to use new floating point API.
>>>>>>>
>>>>>>> Thanks,
>>>>>>> Alexandr.
>>>>>>>
>>>>>>>> --Semyon
>>>>>>>>
>>>>>>>>
>>>>>>>> On 19.08.2016 11:03, Alexandr Scherbatiy wrote:
>>>>>>>>> On 8/19/2016 2:25 AM, Philip Race wrote:
>>>>>>>>>> OK .. I do not know enough about how modelToView is used by Swing
>>>>>>>>>> to know what is really needed here. Someone with a bit more Swing
>>>>>>>>>> background needs to chime in. I was encouraged that the *API*
>>>>>>>>>> surface
>>>>>>>>>> of the changes was much smaller than it had seemed from the
>>>>>>>>>> webrev
>>>>>>>>>> but maybe that is because you did not include everything. For
>>>>>>>>>> example
>>>>>>>>>> although they are just subclassing the method overrides in
>>>>>>>>>> PasswordView
>>>>>>>>>> since that is a public class would become part of the spec ..
>>>>>>>>>> would they not ?
>>>>>>>>>> Just like the "int" counterparts today :-
>>>>>>>>>> https://docs.oracle.com/javase/8/docs/api/javax/swing/text/PasswordView.html
>>>>>>>>>>
>>>>>>>>>> Put another way I was looking for what the content of the CCC
>>>>>>>>>> would be.
>>>>>>>>> Here is the updated version of the public API change which
>>>>>>>>> includes overridden deprecated methods:
>>>>>>>>> http://cr.openjdk.java.net/~alexsch/8156217/webrev.05/public-api.01
>>>>>>>>>
>>>>>>>>> Thanks,
>>>>>>>>> Alexandr.
>>>>>>>>>>
>>>>>>>>>> -phil.
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> On 8/15/16, 11:48 AM, Alexander Scherbatiy wrote:
>>>>>>>>>>> On 15/08/16 21:43, Phil Race wrote:
>>>>>>>>>>>> Why is the caret support added in here ? Same for the
>>>>>>>>>>>> modelToView
>>>>>>>>>>>> That will just hold this up as the reasoning behind needing
>>>>>>>>>>>> those changes is not something
>>>>>>>>>>>> I have yet been able to convince myself about - even after
>>>>>>>>>>>> reading your last email.
>>>>>>>>>>>
>>>>>>>>>>> The main change for the Caret public API (methods
>>>>>>>>>>> Caret.getMagicCaretPosition2D()/setMagicCaretPosition2D(Point2D
>>>>>>>>>>> p)) is not included in the current fix. I only moved the new
>>>>>>>>>>> methods JTextComponent.modelToView2D(int
>>>>>>>>>>> pos)/viewToModel2D(Point2D pt) from the fix for the Caret to
>>>>>>>>>>> this fix. These methods are used not only for caret but in
>>>>>>>>>>> other cases like mouse handling, text dragging and others.
>>>>>>>>>>>
>>>>>>>>>>> Thanks,
>>>>>>>>>>> Alexandr.
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> -phil.
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> On 08/15/2016 04:13 AM, Alexandr Scherbatiy wrote:
>>>>>>>>>>>>>
>>>>>>>>>>>>> Hello,
>>>>>>>>>>>>>
>>>>>>>>>>>>> Could you review the updated fix?
>>>>>>>>>>>>> webrev which contains only change in public API:
>>>>>>>>>>>>> http://cr.openjdk.java.net/~alexsch/8156217/webrev.05/public-api
>>>>>>>>>>>>> webrev with contains all changes:
>>>>>>>>>>>>> http://cr.openjdk.java.net/~alexsch/8156217/webrev.05/all
>>>>>>>>>>>>>
>>>>>>>>>>>>> - methods with int coordinates are deprecated
>>>>>>>>>>>>> - public
>>>>>>>>>>>>> isUseFloatingPointAPI()/setUseFloatingPointAPI() methods
>>>>>>>>>>>>> are added to the PlainView and WrappedPlainView classes
>>>>>>>>>>>>> - JTextComponent.modelToView2D(int
>>>>>>>>>>>>> pos)/viewToModel2D(Point2D pt) public methods from fix
>>>>>>>>>>>>> JDK-8163124 Add floating point API support to
>>>>>>>>>>>>> javax.swing.text.Caret
>>>>>>>>>>>>> are added
>>>>>>>>>>>>> - some @implSpec descriptions are removed from the new
>>>>>>>>>>>>> text drawing methods with floating point arguments
>>>>>>>>>>>>> - Built-in L&Fs are updated to use floating point API in
>>>>>>>>>>>>> standard Java text components
>>>>>>>>>>>>>
>>>>>>>>>>>>> Thanks,
>>>>>>>>>>>>> Alexandr.
>>>>>>>>>>>>>
>>>>>>>>>>>>> On 7/28/2016 5:38 PM, Alexandr Scherbatiy wrote:
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> See comments inline.
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> On 7/26/2016 11:57 PM, Phil Race wrote:
>>>>>>>>>>>>>>> I have a lot of doubts about this as well as trouble
>>>>>>>>>>>>>>> getting my head around all of it.
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> Given that apps need to 'buy in' to the floating point I
>>>>>>>>>>>>>>> am not sure what we are gaining
>>>>>>>>>>>>>>> but I need to make sure I understand the problem.
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> It affects only the methods that the 3rd party code can
>>>>>>>>>>>>>>> over-ride
>>>>>>>>>>>>>>> in subclasses and that are called by the JDK internal code.
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> There are just two protected methods that matter :-
>>>>>>>>>>>>>>> PlainView.drawSelectedText(..)
>>>>>>>>>>>>>>> and
>>>>>>>>>>>>>>> PlainView.drawUnselectedText(..)
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> The hidpi precison matters since they are drawing a
>>>>>>>>>>>>>>> sub-range of the text.
>>>>>>>>>>>>>>> Is there any other method that matters / is used in this
>>>>>>>>>>>>>>> way ?
>>>>>>>>>>>>>> I have found the following methods which relate to text
>>>>>>>>>>>>>> drawing, can be overridden and could have floating point
>>>>>>>>>>>>>> coordinates:
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> javax.swing.text.PlainView.drawLine(...)
>>>>>>>>>>>>>> javax.swing.text.PlainView.lineToRect(...)
>>>>>>>>>>>>>> javax.swing.text.PasswordView.drawEchoCharacter(...)
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> javax.swing.plaf.TextUI.modelToView(...)
>>>>>>>>>>>>>> javax.swing.plaf.TextUI.viewToModel(...)
>>>>>>>>>>>>>> javax.swing.plaf.TextUI.getToolTipText(...)
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> There is also a method which relates to a caret position
>>>>>>>>>>>>>> in a text:
>>>>>>>>>>>>>> javax.swing.text.DefaultCaret.setMagicCaretPosition(Point p)
>>>>>>>>>>>>>> This requires additional investigation because
>>>>>>>>>>>>>> DefaultCaret extends Rectangle and so its coordinates
>>>>>>>>>>>>>> can't be float.
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> Since 3rd party code is not over-riding these they will
>>>>>>>>>>>>>>> get the JDK
>>>>>>>>>>>>>>> super-class version, thus losing any customisation they
>>>>>>>>>>>>>>> might have done
>>>>>>>>>>>>>>> in the no-longer-called int version.
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> Assuming that is correct, what customisation would be
>>>>>>>>>>>>>>> lost and how much does it matter?
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> The example is javax.swing.text.PasswordView class which
>>>>>>>>>>>>>> overrides drawSelectedText(...)/drawUnselectedText(...)
>>>>>>>>>>>>>> methods and draws echo chars instead of text.
>>>>>>>>>>>>>> The similar can be done in a custom component:
>>>>>>>>>>>>>> --------
>>>>>>>>>>>>>> public class CustomPasswordField extends FieldView {
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> @Override
>>>>>>>>>>>>>> protected int drawSelectedText(Graphics g, int x,
>>>>>>>>>>>>>> int y, int p0, int p1) throws BadLocationException {
>>>>>>>>>>>>>> // draw echo chars
>>>>>>>>>>>>>> }
>>>>>>>>>>>>>> }
>>>>>>>>>>>>>> --------
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Switching to support new methods with floating point
>>>>>>>>>>>>>> coordinates will lead that real text will be shown for
>>>>>>>>>>>>>> old applications in password fields.
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> My prefernce is to deprecate the int versions and always
>>>>>>>>>>>>>>> call the float versions
>>>>>>>>>>>>>>> rather than the opt-in approach.
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> Actually my real preference would be to come up with
>>>>>>>>>>>>>>> something that does
>>>>>>>>>>>>>>> not involve drawing the text in chunks like this.
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> ie Swing should use AttributedCharacterIterator .. it
>>>>>>>>>>>>>>> looks like the code to
>>>>>>>>>>>>>>> do this might already be there !
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> 106 private float drawElement(int lineIndex, Element
>>>>>>>>>>>>>>> elem, Graphics g,
>>>>>>>>>>>>>>> 107 float x, float y, boolean fractionalCharBounds)
>>>>>>>>>>>>>>> 108 throws BadLocationException
>>>>>>>>>>>>>>> 109 {
>>>>>>>>>>>>>>> 110 int p0 = elem.getStartOffset();
>>>>>>>>>>>>>>> 111 int p1 = elem.getEndOffset();
>>>>>>>>>>>>>>> 112 p1 = Math.min(getDocument().getLength(), p1);
>>>>>>>>>>>>>>> 113
>>>>>>>>>>>>>>> 114 if (lineIndex == 0) {
>>>>>>>>>>>>>>> 115 x += firstLineOffset;
>>>>>>>>>>>>>>> 116 }
>>>>>>>>>>>>>>> 117 AttributeSet attr = elem.getAttributes();
>>>>>>>>>>>>>>> 118 if (Utilities.isComposedTextAttributeDefined(attr)) {
>>>>>>>>>>>>>>> 119 g.setColor(unselected);
>>>>>>>>>>>>>>> 120 x = Utilities.drawComposedText(this, attr, g, x, y,
>>>>>>>>>>>>>>> 121 p0-elem.getStartOffset(),
>>>>>>>>>>>>>>> 122 p1-elem.getStartOffset());
>>>>>>>>>>>>>>> 123 } else {
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> In fact what *that* illustrates is that applications
>>>>>>>>>>>>>>> already cannot expect
>>>>>>>>>>>>>>> their over-ridden methods to be called, so this fix is
>>>>>>>>>>>>>>> trying to fix something
>>>>>>>>>>>>>>> that can't be fixed.
>>>>>>>>>>>>>> The javadoc for the "protected PlainView.drawLine(...)"
>>>>>>>>>>>>>> method is:
>>>>>>>>>>>>>> ---------
>>>>>>>>>>>>>> /**
>>>>>>>>>>>>>> * Renders a line of text, suppressing whitespace at
>>>>>>>>>>>>>> the end
>>>>>>>>>>>>>> * and expanding any tabs. This is implemented to
>>>>>>>>>>>>>> make calls
>>>>>>>>>>>>>> * to the methods {@code drawUnselectedText} and
>>>>>>>>>>>>>> * {@code drawSelectedText} so that the way selected and
>>>>>>>>>>>>>> * unselected text are rendered can be customized.
>>>>>>>>>>>>>> ---------
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Applications can rely on this behaviour and stopping to
>>>>>>>>>>>>>> call the drawSelectedText(...)/drawUnselectedText(...)
>>>>>>>>>>>>>> methods with int coordinates will be incompatible change.
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> So why can't we do that ? Just deprecate those int
>>>>>>>>>>>>>>> methods, don't add
>>>>>>>>>>>>>>> the float methods and use ACI ..
>>>>>>>>>>>>>> New float methods allow to easily migrate on new API
>>>>>>>>>>>>>> for applications without significant changes.
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> BTW getTabSize() is supposed to be a character count
>>>>>>>>>>>>>>> isn't it ? Not a pixel
>>>>>>>>>>>>>>> count. So why does it need a float version.
>>>>>>>>>>>>>> Could you review the updated fix:
>>>>>>>>>>>>>> http://cr.openjdk.java.net/~alexsch/8156217/webrev.04
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> - methods with int coordinates which can be
>>>>>>>>>>>>>> overridden are deprecated
>>>>>>>>>>>>>> - getFractionalTabSize() method is removed
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Thanks,
>>>>>>>>>>>>>> Alexandr.
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> -phil
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> On 06/30/2016 08:50 AM, Alexandr Scherbatiy wrote:
>>>>>>>>>>>>>>>> On 6/28/2016 8:14 PM, Alan Snyder wrote:
>>>>>>>>>>>>>>>>> Suppose an application is only partially fixed to
>>>>>>>>>>>>>>>>> use/override the floating point methods. Perhaps it
>>>>>>>>>>>>>>>>> uses a library that has not been fixed.
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>> Is there a more fine grained way to detect programmer
>>>>>>>>>>>>>>>>> awareness or lack of awareness of the new methods?
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> Here is a slightly updated version which adds public
>>>>>>>>>>>>>>>> isUseFloatingPointAPI()/setUseFloatingPointAPI()
>>>>>>>>>>>>>>>> methods to the PlainView and WrappedPlainView classes:
>>>>>>>>>>>>>>>> http://cr.openjdk.java.net/~alexsch/8156217/webrev.02
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> Using the floating point API is disabled by default
>>>>>>>>>>>>>>>> and enabled for standard Swing text component classes.
>>>>>>>>>>>>>>>> This has advantage that selection will work for text
>>>>>>>>>>>>>>>> component in users applications on HiDPI display.
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> But it still has the same problem. Applications which
>>>>>>>>>>>>>>>> use custom View classes needs to updated them to
>>>>>>>>>>>>>>>> implement corresponding text drawing methods with
>>>>>>>>>>>>>>>> floating point arguments and enable the floating point
>>>>>>>>>>>>>>>> API usage.
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> Thanks,
>>>>>>>>>>>>>>>> Alexandr.
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>> Alan
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> On Jun 28, 2016, at 9:59 AM, Alexandr Scherbatiy
>>>>>>>>>>>>>>>>>> <alexandr.scherbatiy at oracle.com
>>>>>>>>>>>>>>>>>> <mailto:alexandr.scherbatiy at oracle.com>> wrote:
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Hello,
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> I tried to merge this fix with the 8132119 Provide
>>>>>>>>>>>>>>>>>> public API for text related methods in SwingUtilities2
>>>>>>>>>>>>>>>>>> and found a flow in the used algorithm.
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> For each method that uses integer coordinates the
>>>>>>>>>>>>>>>>>> fix adds a pair with floating point arguments.
>>>>>>>>>>>>>>>>>> The fix 8156217 uses only methods with floating
>>>>>>>>>>>>>>>>>> point values to correctly handle a selected text.
>>>>>>>>>>>>>>>>>> This leads that overridden method with integer
>>>>>>>>>>>>>>>>>> arguments in user code is not called anymore.
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> I think that this can be handled in the following way:
>>>>>>>>>>>>>>>>>> - Add a property that enables to use methods with
>>>>>>>>>>>>>>>>>> floating point arguments in Swing.
>>>>>>>>>>>>>>>>>> By default it is false and all work as before. The
>>>>>>>>>>>>>>>>>> issue with selected text is reproduced.
>>>>>>>>>>>>>>>>>> An application with enabled property does not have
>>>>>>>>>>>>>>>>>> issue with the selected text but a user should override
>>>>>>>>>>>>>>>>>> all methods with floating point values if he uses
>>>>>>>>>>>>>>>>>> corresponding methods with integer values.
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Here is a proposed solution where new public system
>>>>>>>>>>>>>>>>>> property "javax.swing.floatingPoints.enabled" is added:
>>>>>>>>>>>>>>>>>> http://cr.openjdk.java.net/~alexsch/8156217/webrev.01
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> - Fix the enhancement JDK-8157461 Glyph image
>>>>>>>>>>>>>>>>>> rendering for HiDPI displays
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Thanks,
>>>>>>>>>>>>>>>>>> Alexandr.
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> On 6/16/2016 6:07 PM, Alexandr Scherbatiy wrote:
>>>>>>>>>>>>>>>>>>> On 6/16/2016 4:47 PM, Alexandr Scherbatiy wrote:
>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>> I tried to look deeper in the code and it seems
>>>>>>>>>>>>>>>>>>>> there is a rounding issue when float values are
>>>>>>>>>>>>>>>>>>>> summed up.
>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>> Suppose a transform with scale 1.5 is used and the
>>>>>>>>>>>>>>>>>>>> 'a' char advance is 10 in a dev space.
>>>>>>>>>>>>>>>>>>>> The 'a' char has advance 10 / 1.5 =
>>>>>>>>>>>>>>>>>>>> 6.666666666666667 as double value and 6.6666665
>>>>>>>>>>>>>>>>>>>> when it is cast to float in user space.
>>>>>>>>>>>>>>>>>>>> The width of a string which consists of 15 'a'
>>>>>>>>>>>>>>>>>>>> chars is 15 * 6.6666665 = 100.000000.
>>>>>>>>>>>>>>>>>>>> But the same width calculated as sum of each glyph
>>>>>>>>>>>>>>>>>>>> advance in StandardGlyphVector.initPositions()
>>>>>>>>>>>>>>>>>>>> method is 99.999992.
>>>>>>>>>>>>>>>>>>>> --------------
>>>>>>>>>>>>>>>>>>>> double scale = 1.5;
>>>>>>>>>>>>>>>>>>>> float advance = (float) (10 / scale);
>>>>>>>>>>>>>>>>>>>> int N = 15;
>>>>>>>>>>>>>>>>>>>> System.out.printf("%d * %f = %f\n", N, advance, N *
>>>>>>>>>>>>>>>>>>>> advance);
>>>>>>>>>>>>>>>>>>>> float sum = 0;
>>>>>>>>>>>>>>>>>>>> for (int i = 0; i < N; i++) {
>>>>>>>>>>>>>>>>>>>> sum += advance;
>>>>>>>>>>>>>>>>>>>> }
>>>>>>>>>>>>>>>>>>>> System.out.printf("sum: %f\n", sum);
>>>>>>>>>>>>>>>>>>>> --------------
>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>> Because of this a string drawn from float position
>>>>>>>>>>>>>>>>>>>> 99.999998 is shifted one pixel left which affects
>>>>>>>>>>>>>>>>>>>> the text selection code in Swing:
>>>>>>>>>>>>>>>>>>>> ------------------------
>>>>>>>>>>>>>>>>>>>> g.scale(1.5, 1.5);
>>>>>>>>>>>>>>>>>>>> String TEXT = "aaaaaaaaaaaaaaaa";
>>>>>>>>>>>>>>>>>>>> Rectangle2D rect =
>>>>>>>>>>>>>>>>>>>> font.getStringBounds(TEXT, 0, index,
>>>>>>>>>>>>>>>>>>>> g.getFontMetrics().getFontRenderContext());
>>>>>>>>>>>>>>>>>>>> float selectedTextPosition = (float)
>>>>>>>>>>>>>>>>>>>> rect.getWidth(); // 99.999992
>>>>>>>>>>>>>>>>>>>> g.drawString(TEXT.substring(0, index), x,
>>>>>>>>>>>>>>>>>>>> y); // non-selected text
>>>>>>>>>>>>>>>>>>>> g.drawString(TEXT.substring(index,
>>>>>>>>>>>>>>>>>>>> TEXT.length()), x + selectedTextPosition, y); //
>>>>>>>>>>>>>>>>>>>> selected text is shifted to one pixel left
>>>>>>>>>>>>>>>>>>>> ------------------------
>>>>>>>>>>>>>>>>>>> The last step is how coordinates are scaled in
>>>>>>>>>>>>>>>>>>> Graphics2D.drawString() method.
>>>>>>>>>>>>>>>>>>> If the graphics has scale 1.5 and zero translate
>>>>>>>>>>>>>>>>>>> the transformed coordinates are:
>>>>>>>>>>>>>>>>>>> (99.999992 + 0) * 1.5 = 149.999985
>>>>>>>>>>>>>>>>>>> (100.000000 + 0) * 1.5 = 150.000000
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> Both of them are rounded to the same value.
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> If the translate is set to integer 1 value:
>>>>>>>>>>>>>>>>>>> (99.999992 + 1) * 1.5 = 151.499989 // shifted
>>>>>>>>>>>>>>>>>>> to one pixel left
>>>>>>>>>>>>>>>>>>> (100.000000 + 1) * 1.5 = 151.500000
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> A position 99.999992 in user space is rounded to
>>>>>>>>>>>>>>>>>>> 151 in dev space.
>>>>>>>>>>>>>>>>>>> A position 100.000000 in user space is rounded to
>>>>>>>>>>>>>>>>>>> 152 in dev space.
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> And this difference can depend on the translate
>>>>>>>>>>>>>>>>>>> even it has integer value in user space because it
>>>>>>>>>>>>>>>>>>> is multiplied on the graphics scale.
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> Thanks,
>>>>>>>>>>>>>>>>>>> Alexandr.
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>> Thanks,
>>>>>>>>>>>>>>>>>>>> Alexandr.
>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>> On 6/2/2016 11:41 PM, Alexandr Scherbatiy wrote:
>>>>>>>>>>>>>>>>>>>>> On 5/31/2016 10:40 PM, Phil Race wrote:
>>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>> I applied this and it is *much* better but there
>>>>>>>>>>>>>>>>>>>>>> still seem to be some tiny quirks.
>>>>>>>>>>>>>>>>>>>>>> When I drag the mouse to select text down and
>>>>>>>>>>>>>>>>>>>>>> then up again, as I pass the
>>>>>>>>>>>>>>>>>>>>>> original mouse click point vertically, repaint
>>>>>>>>>>>>>>>>>>>>>> seem to jiggle vertically by a pixel.
>>>>>>>>>>>>>>>>>>>>>> Perhaps a rounding issue in the repaint code's
>>>>>>>>>>>>>>>>>>>>>> calculation of the location of
>>>>>>>>>>>>>>>>>>>>>> the target y. I think I may see the same in
>>>>>>>>>>>>>>>>>>>>>> left/right dragging along a line too.
>>>>>>>>>>>>>>>>>>>>>> So I think this is repaint and not text related.
>>>>>>>>>>>>>>>>>>>>>> Can you take a look.
>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>> I am able to reproduce this only using a
>>>>>>>>>>>>>>>>>>>>> floating point scale.
>>>>>>>>>>>>>>>>>>>>> It looks like 2d issue. I used a test which
>>>>>>>>>>>>>>>>>>>>> draws a text in two pieces. The second piece of
>>>>>>>>>>>>>>>>>>>>> the text is shifted from the first piece by the
>>>>>>>>>>>>>>>>>>>>> floating point size of the the first piece of the
>>>>>>>>>>>>>>>>>>>>> text.
>>>>>>>>>>>>>>>>>>>>> -----------
>>>>>>>>>>>>>>>>>>>>> Rectangle2D rect = font.getStringBounds(TEXT,
>>>>>>>>>>>>>>>>>>>>> 0, index, g.getFontMetrics().getFontRenderContext());
>>>>>>>>>>>>>>>>>>>>> float selectedTextPosition = (float)
>>>>>>>>>>>>>>>>>>>>> rect.getWidth();
>>>>>>>>>>>>>>>>>>>>> g.drawString(TEXT.substring(0, index), x, y);
>>>>>>>>>>>>>>>>>>>>> g.drawString(TEXT.substring(index, TEXT.length()),
>>>>>>>>>>>>>>>>>>>>> x + selectedTextPosition, y);
>>>>>>>>>>>>>>>>>>>>> -----------
>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>> The second piece of the text can be shifted in
>>>>>>>>>>>>>>>>>>>>> the 2 cases:
>>>>>>>>>>>>>>>>>>>>> a) graphics scale is 1.5 and translation is 1.
>>>>>>>>>>>>>>>>>>>>> b) graphics scale is 2.25 without applied
>>>>>>>>>>>>>>>>>>>>> translation
>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>> I have filed an issue on it:
>>>>>>>>>>>>>>>>>>>>> JDK-8158370 Text drawn from float pointing
>>>>>>>>>>>>>>>>>>>>> position and with float pointing scale is shifted
>>>>>>>>>>>>>>>>>>>>> https://bugs.openjdk.java.net/browse/JDK-8158370
>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>> Thanks,
>>>>>>>>>>>>>>>>>>>>> Alexandr.
>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>> -phil.
>>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>> On 05/06/2016 12:31 PM, Alexandr Scherbatiy wrote:
>>>>>>>>>>>>>>>>>>>>>>> Hello,
>>>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>>> Could you review the fix:
>>>>>>>>>>>>>>>>>>>>>>> bug:
>>>>>>>>>>>>>>>>>>>>>>> https://bugs.openjdk.java.net/browse/JDK-8156217
>>>>>>>>>>>>>>>>>>>>>>> webrev:
>>>>>>>>>>>>>>>>>>>>>>> http://cr.openjdk.java.net/~alexsch/8156217/webrev.00
>>>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>>> This is the second part of the fix related to
>>>>>>>>>>>>>>>>>>>>>>> the fact that char width can be fractional in
>>>>>>>>>>>>>>>>>>>>>>> user space.
>>>>>>>>>>>>>>>>>>>>>>> http://mail.openjdk.java.net/pipermail/swing-dev/2016-May/005814.html
>>>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>>> The Font.getStringBounds(...) method is used
>>>>>>>>>>>>>>>>>>>>>>> for the fractional string width calculation by
>>>>>>>>>>>>>>>>>>>>>>> Swing in user space.
>>>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>>> Thanks,
>>>>>>>>>>>>>>>>>>>>>>> Alexandr.
>>>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>
>>>>>
>>>>
>>>
>>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.openjdk.java.net/pipermail/swing-dev/attachments/20160912/3fca4add/attachment.html>
More information about the swing-dev
mailing list