Skip sub pixel positions test if font smoothing is off

Copy/paste the test from qapplication_mac.mm where we detect if font
smoothing is actually on by drawing an x into a buffer and checking
the result for non-gray pixels.

Reviewed-by: Jiang Jiang

1 files changed, 25 insertions, 0 deletions

diff --git a/tests/auto/qpainter/tst_qpainter.cpp b/tests/auto/qpainter/tst_qpainter.cpp
index d16c37a..9b8444c 100644
--- a/tests/auto/qpainter/tst_qpainter.cpp
+++ b/tests/auto/qpainter/tst_qpainter.cpp
@@ -4570,6 +4570,31 @@ void tst_QPainter::drawText_subPixelPositionsInRaster_qtbug5053()
     QSKIP("Only Mac/Cocoa supports sub pixel positions in raster engine currently", SkipAll);
 #endif
 
+    int w = 10, h = 10;
+    QImage image(w, h, QImage::Format_RGB32);
+    image.fill(0xffffffff);
+    QPainter p(&image);
+    p.drawText(0, h, "X\\");
+    p.end();
+
+    bool foundNonGrayPixel = false;
+    const int *bits = (const int *) ((const QImage &) image).bits();
+    int bpl = image.bytesPerLine() / 4;
+    for (int y=0; y<w; ++y) {
+        for (int x=0; x<h; ++x) {
+            int r = qRed(bits[x]);
+            int g = qGreen(bits[x]);
+            int b = qBlue(bits[x]);
+            if (r != g || r != b) {
+                foundNonGrayPixel = true;
+                break;
+            }
+        }
+        bits += bpl;
+    }
+    if (!foundNonGrayPixel)
+        QSKIP("Font smoothing must be turned on for this test", SkipAll);
+
     QFontMetricsF fm(qApp->font());
 
     QImage baseLine(fm.width(QChar::fromLatin1('e')), fm.height(), QImage::Format_RGB32);