Adjust distance field glyph and font atlas sizes to maximize storage.

src/gpu/GrFontAtlasSizes.h

Index: src/gpu/GrFontAtlasSizes.h
diff --git a/src/gpu/GrFontAtlasSizes.h b/src/gpu/GrFontAtlasSizes.h
index 24897e4a7ae2e0d4539767b8d0d60f990f49abe8..5a1821cdcebd3c821c7adced02e3ef40266c599e 100644
--- a/src/gpu/GrFontAtlasSizes.h
+++ b/src/gpu/GrFontAtlasSizes.h
@@ -9,20 +9,27 @@
 #ifndef GrFontAtlasSizes_DEFINED
 #define GrFontAtlasSizes_DEFINED
 
-#define GR_FONT_ATLAS_TEXTURE_WIDTH  1024
-#define GR_FONT_ATLAS_TEXTURE_HEIGHT 2048
+#include "SkDistanceFieldGen.h"
 
-#define GR_FONT_ATLAS_PLOT_WIDTH     256
-#define GR_FONT_ATLAS_PLOT_HEIGHT    256
+#define GR_SDF_MAX_SIZE              156
 
-#define GR_FONT_ATLAS_NUM_PLOTS_X   (GR_FONT_ATLAS_TEXTURE_WIDTH / GR_FONT_ATLAS_PLOT_WIDTH)
-#define GR_FONT_ATLAS_NUM_PLOTS_Y   (GR_FONT_ATLAS_TEXTURE_HEIGHT / GR_FONT_ATLAS_PLOT_HEIGHT)
+// allows us to fit four of the largest distance field glyphs
+#define GR_FONT_ATLAS_PLOT_WIDTH     (2*(GR_SDF_MAX_SIZE+2*SK_DistanceFieldPad))
+#define GR_FONT_ATLAS_PLOT_HEIGHT    (2*(GR_SDF_MAX_SIZE+2*SK_DistanceFieldPad))
+
+#define GR_FONT_ATLAS_NUM_PLOTS_X    5
+#define GR_FONT_ATLAS_NUM_PLOTS_Y    6
+
+#define GR_FONT_ATLAS_TEXTURE_WIDTH  (GR_FONT_ATLAS_PLOT_WIDTH*GR_FONT_ATLAS_NUM_PLOTS_X)
+SK_COMPILE_ASSERT(GR_FONT_ATLAS_TEXTURE_WIDTH == 1640, font_atlas_unexpected_size);
+#define GR_FONT_ATLAS_TEXTURE_HEIGHT (GR_FONT_ATLAS_PLOT_HEIGHT*GR_FONT_ATLAS_NUM_PLOTS_Y)
+SK_COMPILE_ASSERT(GR_FONT_ATLAS_TEXTURE_HEIGHT == 1968, font_atlas_unexpected_size);
 
 // one over width and height
-#define GR_FONT_ATLAS_RECIP_WIDTH    "0.0009765625"
-#define GR_FONT_ATLAS_RECIP_HEIGHT   "0.00048828125"
+#define GR_FONT_ATLAS_RECIP_WIDTH    "0.00060975609"
+#define GR_FONT_ATLAS_RECIP_HEIGHT   "0.00050813008"
 
 // 1/(3*width)
-#define GR_FONT_ATLAS_LCD_DELTA      "0.00032552083"
+#define GR_FONT_ATLAS_LCD_DELTA      "0.00020325203"
 
 #endif