Hi Phil,
When we call print() it calls RasterPrinterJob#printPage() which sets
peekGraphics.transform([4.16,0,0][0,4.16,0]) as obtained from
xscale=4.16 [getXRes()=300 / 72.0] ,yscale=4.16
It calls SunGraphics2D.transform which was identity transform [1.0, 0.0,
0.0] [0.0, 1.0, 0.0] calls transform.concatenate(peekgraphicsTx) and
stores as ([4.16,0,0][0,4.16,0])
Then RasterPrinterJob#printPage() again calls peekGraphics.transform(new
AffineTransform(page.getMatrix()));
where page.getMatrix() returns 0.0, -1.0, 1.0, 0.0, 0.0, 841.88 and
peekGraphics transform now becomes [0.0, 1.0, 0.0] [-1.0, 0.0, 841.88]
which calls SunGraphics2D#transform() where it again does
transform.concatenate(peekgraphicsTx)
so the transform becomes [m00=0, m01=4.16, m02=0][m10=-4.16, m11=0,
m12=3507.873]
Now scaleX obtains value from g2d.getTransform().getScaleX() which
returns SunGraphics2D stored transform.m00 which is 0 and scaleY is
m11=0 so scaleX,scaleY becomes 0.
Regards
Prasanta
On 5/19/2016 4:03 AM, Phil Race wrote:
It sounds like scalex & scaley are 0 and are then used in calculations
which
results in the NaN ? So why are they zero to begin with ?
-phil.
On 5/16/2016 3:32 AM, prasanta sadhukhan wrote:
Hi All,
Please review a fix for jdk9 whereby it is seen that
A StackOverflowError occurs when printing in landscape orientation
with a scaled and transformed graphics object.
at sun.print.PSPrinterJob.prepDrawing(PSPrinterJob.java:1610)
at sun.print.PSPrinterJob.beginPath(PSPrinterJob.java:1319)
at sun.print.PSPrinterJob.convertToPSPath(PSPrinterJob.java:1793)
at sun.print.PSPrinterJob$GState.emitPSClip(PSPrinterJob.java:1718)
at sun.print.PSPrinterJob.prepDrawing(PSPrinterJob.java:1625)
at sun.print.PSPrinterJob.beginPath(PSPrinterJob.java:1319)
at sun.print.PSPrinterJob.convertToPSPath(PSPrinterJob.java:1793)
at sun.print.PSPrinterJob$GState.emitPSClip(PSPrinterJob.java:1718)
at sun.print.PSPrinterJob.prepDrawing(PSPrinterJob.java:1625)
Bug: https://bugs.openjdk.java.net/browse/JDK-6842011
webrev: http://cr.openjdk.java.net/~psadhukhan/6842011/webrev.00/
StackOverflowError is occuring because the scalex, scaley for
landscape orientation was 0 so when the testcase tries to scale with
these scale factors
using g2d.scale( 1 / scalex, 1 / scaley );
it creates a AffineTransform of NaN transformation. Now, In linux,
when the PS print drawing information is being prepared, it calls
prepDrawing() where it checks
getGState().mTransform.equals(mLastTransform) and since NaN values
cannot be compared it results in "false", causing erroneous
"grestore" postscript command to be issued and remove a GState from
the stack so isOuterGState() becomes true which causes emitPSClip()
to be called which calls
prepDrawing() again via convertToPSPath() , beginPath() and since
isOuterState() returns true due to transform not being equal it again
calls emitPSClip() causing a recursion.
The fix was to check if transform is NaN and do not fill the
devicePath if it is so, so that erroeous drawing is not done.
So, it will print out a blank page.
In windows, the testcase prints out a blank page. In mac, the
testcase prints a 2x2 rectangle.
Regards
Prasanta
