Re: [OpenJDK 2D-Dev] Why does the OpenGL pipeline not use setupBlitVector?

[Jim Graham]

This is often a problem that can happen if you don't have a prototype 
for the function.  The default passing semantics for floating point is 
to pass them as doubles unless there is a prototype that says that they 
are floats.

Did you get the prototype correct, and did you make sure it was included?
                ...jim

Clemens Eisserer wrote:
Hi again,

I now inserted printf-statements to see the value of the parameters
before and after passing them:
In X11TextRenderer:          numGlpyhs:10, usePositions:0,
subpixPos:0, rgbOrder:0, lcdc:140, glypx:100.500000,
glyphy:400.500000, Images: -1376605040, NULL
In  X11TextRenderer_md: numGlpyhs:10, usePositions:0, subpixPos:0,
rgbOrder:0, lcdc:140, glypx:0.000000, glyphy:3.392578, Images: 0
Positions:1081673728

So somehow it looks like passing the jfloats causes troubles, after
commenting them out, everything works as expected:
In X11TextRenderer: numGlpyhs:10, usePositions:0, subpixPos:0,
rgbOrder:0, lcdc:140, glypx:100.500000, glyphy:400.50000, Images:
-1376605792
In _md: numGlpyhs:10, usePositions:0, subpixPos:0, rgbOrder:0,
lcdc:140, glypx:-0.000000, glyphy:-0.000000, Images: -1376605792,
Positions:0

Any idea why passing the jfloats fail?

Thank you in advance, lg Clemens


2008/6/3 Clemens Eisserer <[EMAIL PROTECTED]>:
Hi Dmitri,

 Did you try to run it with -Xcheck:jni (preferably on a fastdebug
 build)? What does it say?
Thanks for the hint, it cleans the array-handle is not valid.

I added printf-statements and Hotspot is of course right, the
"original" object handle was != NULL, but the one I passed is zero.
The strange thing is if I call a method in the same shared library
(fontmanager.so) the handle is passed correctly, but when calling into
libmawt.so the array-handle is NULL.
I pass the array-handles by value, is this ok?

For now I could work-arround that by simply calling
GetPrimitiveArrayCritical in the first method, however thats somehow
strange and I would like to understand where my mistake is to learn of
my faults ;)

Thanks a lot for your patience, Clemens

One thing that also puzzles me is how the compiler knows about
AWTXRDrawGlyphList?
There's no header-file which specifies it, does the compiler guess?
This is the how the code looks like:

1.) In libmawt.so the method which is called and crashes:
void AWTXRDrawGlyphList
   (JNIEnv *env, jobject self,
    jlong dstData, jint numGlyphs, jboolean usePositions,
                   jboolean subPixPos, jboolean rgbOrder, jint lcdContrast,
                   jfloat glyphListOrigX, jfloat glyphListOrigY,
                   jlongArray imgArray, jfloatArray posArray)
{
   images = (jlong *) (*env)->GetPrimitiveArrayCritical(env, imgArray, NULL);
}

2.)The method called from JNI in libfontmanager.so and a test-dummy method:
JNIEXPORT void JNICALL Java_sun_font_X11TextRenderer_doDrawGlyphList
 //Method called from JNI
   (JNIEnv *env, jobject xtr,
    jlong dstData, jint totalGlyphs, jboolean usePositions,
                   jboolean subPixPos, jboolean rgbOrder, jint lcdContrast,
                   jfloat glyphListOrigX, jfloat glyphListOrigY,
                   jlongArray images, jfloatArray positions)
{
 TESTDrawGlyphList(env, xtr, dstData, totalGlyphs, usePositions,
 //Does not crash
                    subPixPos, rgbOrder, lcdContrast, glyphListOrigX,
                    glyphListOrigY, images, positions);

 AWTXRDrawGlyphList(env, xtr, dstData, totalGlyphs, usePositions,
//Does crash, because images == NULL
                    subPixPos, rgbOrder, lcdContrast, glyphListOrigX,
                    glyphListOrigY, images, positions);
}

JNIEXPORT void TESTDrawGlyphList //DummyTestMethod
   (JNIEnv *env, jobject self,
    jlong dstData, jint numGlyphs, jboolean usePositions,
                   jboolean subPixPos, jboolean rgbOrder, jint lcdContrast,
                   jfloat glyphListOrigX, jfloat glyphListOrigY,
                   jlongArray imgArray, jfloatArray posArray)
{
   jlong *images;
   images = (jlong *) (*env)->GetPrimitiveArrayCritical(env, imgArray, NULL);
}

These are the outputs when I run the code with Xcheck:jni:
Pointer: -1388390664 <- Value of imgArray-handle before passed to the
2nd method in libmawt.so
Pointer: 0 <- Passed value
FATAL ERROR in native method: Non-array passed to JNI array operations

and this is without XCheck:jni:
V  [libjvm.so+0x24252b]
C  [libmawt.so+0x1fc81]  AWTXRDrawGlyphList+0xa1
C  [libfontmanager.so+0xb393]
Java_sun_font_X11TextRenderer_doDrawGlyphList+0x113
j  sun.font.X11TextRenderer.doDrawGlyphList(JIZZZIFF[J[F)V+0

So the first call succeed (which basically does exectly the same, its
just in another shared library), but the second time the parameter is
not passed :-/