gdx-ttf fonts bleed black color onto glyphs when they have shadows of…

… any color (#7391)

* Add default transparent color to shadow pixmap

* Improved performance by eliminating unecessary fill

* Update FreeTypeFontGenerator.java

* Added missing import

* Updated changelog

* Fixed format violation

* Update CHANGES

CHANGES

@@ -12,6 +12,7 @@
 - Android: Add configuration option to render under the cutout if available on the device.
 - Fix: Keep SelectBox popup from extending past right edge of stage.
 - Added Framebuffer multisample support (see GL31FrameBufferMultisampleTest.java for basic usage)
+- Fix: Fonts generated with gdx-freetype no longer bleed when drawn with a shadow
 
 [1.12.1]
 - LWJGL3 Improvement: Audio device is automatically switched if it was changed in the operating system.

extensions/gdx-freetype/src/com/badlogic/gdx/graphics/g2d/freetype/FreeTypeFontGenerator.java

@@ -28,6 +28,7 @@
 import com.badlogic.gdx.graphics.g2d.BitmapFont;
 import com.badlogic.gdx.graphics.g2d.BitmapFont.BitmapFontData;
 import com.badlogic.gdx.graphics.g2d.BitmapFont.Glyph;
+import com.badlogic.gdx.graphics.g2d.Gdx2DPixmap;
 import com.badlogic.gdx.graphics.g2d.GlyphLayout.GlyphRun;
 import com.badlogic.gdx.graphics.g2d.PixmapPacker;
 import com.badlogic.gdx.graphics.g2d.PixmapPacker.GuillotineStrategy;
@@ -527,7 +528,11 @@ public FreeTypeBitmapFontData generateData (FreeTypeFontParameter parameter, Fre
 				int mainW = mainPixmap.getWidth(), mainH = mainPixmap.getHeight();
 				int shadowOffsetX = Math.max(parameter.shadowOffsetX, 0), shadowOffsetY = Math.max(parameter.shadowOffsetY, 0);
 				int shadowW = mainW + Math.abs(parameter.shadowOffsetX), shadowH = mainH + Math.abs(parameter.shadowOffsetY);
-				Pixmap shadowPixmap = new Pixmap(shadowW, shadowH, mainPixmap.getFormat());
+				// use the Gdx2DPixmap constructor to avoid filling the pixmap twice
+				Pixmap shadowPixmap = new Pixmap(
+					new Gdx2DPixmap(shadowW, shadowH, Pixmap.Format.toGdx2DPixmapFormat(mainPixmap.getFormat())));
+				shadowPixmap.setColor(packer.getTransparentColor());
+				shadowPixmap.fill();
 
 				Color shadowColor = parameter.shadowColor;
 				float a = shadowColor.a;