8204929: Fonts with embedded bitmaps are not always rotated

Reviewed-by: bae

src/java.desktop/share/native/libfontmanager/freetypeScaler.c

@@ -364,6 +364,19 @@ Java_sun_font_FreetypeFontScaler_createScalerContextNative(
     context->doBold = (boldness != 1.0);
     context->doItalize = (italic != 0);
 
+    /* freetype is very keen to use embedded bitmaps, even if it knows
+     * there is a rotation or you asked for antialiasing.
+     * In the rendering path we will check useSBits and disable
+     * bitmaps unless it is set. And here we set it only if none
+     * of the conditions invalidate using it.
+     * Note that we allow embedded bitmaps for the LCD case.
+     */
+    if ((aa != TEXT_AA_ON) && (fm != TEXT_FM_ON) &&
+        !context->doBold && !context->doItalize &&
+        (context->transform.yx == 0) && (context->transform.xy == 0))
+    {
+        context->useSbits = 1;
+    }
     return ptr_to_jlong(context);
 }
 
@@ -685,9 +698,8 @@ Java_sun_font_FreetypeFontScaler_getGlyphImageNative(
         return ptr_to_jlong(getNullGlyphImage());
     }
 
-    /* if algorithmic styling is required then we do not request bitmap */
-    if (context->doBold || context->doItalize) {
-        renderFlags =  FT_LOAD_DEFAULT;
+    if (!context->useSbits) {
+        renderFlags |= FT_LOAD_NO_BITMAP;
     }
 
     /* NB: in case of non identity transform

test/jdk/java/awt/FontClass/GlyphRotationTest.java

@@ -0,0 +1,87 @@
+/*
+ * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 8204929
+ * @summary test rotation of font with embedded bitmaps
+ * @run main GlyphRotationTest
+ */
+
+import java.awt.Color;
+import java.awt.Font;
+import java.awt.Graphics2D;
+import java.awt.geom.AffineTransform;
+import java.awt.image.BufferedImage;
+import javax.imageio.ImageIO;
+
+public class GlyphRotationTest {
+
+    public static final String fontName = "MS UI Gothic";
+    public static Font font;
+    public static final int SZ = 50;
+
+    public static void main(String[] args) {
+        font = new Font(fontName, Font.PLAIN, 15);
+        if (!font.getFamily(java.util.Locale.ENGLISH).equals(fontName)) {
+            return;
+        }
+        BufferedImage bi = new BufferedImage(SZ,SZ,BufferedImage.TYPE_INT_RGB);
+        Graphics2D g2d = bi.createGraphics();
+        g2d.setColor(Color.white);
+        g2d.fillRect(0, 0, SZ, SZ);
+        g2d.setColor(Color.black);
+        g2d.setFont(font);
+        g2d.drawString("1", SZ/2, SZ/2);
+        int pixCnt1 = countPixels(bi);
+        AffineTransform at = AffineTransform.getRotateInstance(Math.PI/2);
+        font = font.deriveFont(Font.PLAIN, at);
+        g2d.setFont(font);
+        g2d.drawString("1", SZ/2, SZ/2);
+        int pixCnt2 = countPixels(bi);
+        if (args.length > 0) {
+            try {
+               ImageIO.write(bi, "png", new java.io.File("im.png"));
+            }  catch (Exception e) {}
+        }
+        if (pixCnt1 == pixCnt2) {
+            String msg = "cnt 1 = " + pixCnt1 + " cnt 2 = " + pixCnt2;
+            throw new RuntimeException(msg);
+        }
+    }
+
+    static int countPixels(BufferedImage bi) {
+        int cnt = 0;
+        int w = bi.getWidth(null);
+        int h = bi.getHeight(null);
+        for (int i=0; i<w; i++) {
+            for (int j=0; j<w; j++) {
+                int rgb = bi.getRGB(i, j) & 0xFFFFFF;
+                if (rgb == 0) {
+                    cnt++;
+                }
+            }
+        }
+        return cnt;
+    }
+}