Extract "text align proc" functions as reusable classes

Extract "text align proc" functions as reusable classes

Extract "text align proc" as reusable classes. These classes need to be used
when writing GrTextContext subclasses.

Moves "text align proc" code that is duplicated in SkDraw and
SkBitmapTextContext to SkDrawProcs.h and SkTextMapState.h. This functionality is
also used in the new GrStencilAndCoverTextContext.

Creates new functor classes SkTextAlignProc and SkTextAlignProcScalar which
represent the previous "text align procs".

Moves TextMapState from SkDraw to SkTextMapStateProc and make it similar functor.

The transform should be comparable in speed, as the compiler can and does avoid
the call and eliminate some of the branches.

Committed: https://skia.googlesource.com/skia/+/cb9a2c8934f009b6ee1ca73d662ac18b285085d9

[Kimmo Kinnunen, 2014-06-12 06:20:42]

Separate commit for easier discussion and review.

Perf tries:

bench_pictures -r $skps/ --config 8888 --repeat 30 

bench --match ext --config 8888


X86 results bench:
                text_16_BW_BK 8888 c          1.93       1.96      -0.03   
-1.6% 
               text_16_LCD_BK 8888 c          4.89       4.92      -0.03   
-0.6% 
                text_16_BW_FF 8888 c          1.94       1.95      -0.01   
-0.5% 
 picture_playback_drawPosText 8888 c        118.92     119.04      -0.12   
-0.1% 
                text_16_AA_FF 8888 c          3.75       3.75      +0.00   
+0.0% 
                text_16_BW_88 8888 c          2.01       2.01      +0.00   
+0.0% 
                text_16_AA_88 8888 c          3.75       3.74      +0.01   
+0.3% 
            text_16_pos_AA_BK 8888 c          3.63       3.62      +0.01   
+0.3% 
               text_16_LCD_88 8888 c          5.25       5.22      +0.03   
+0.6% 
    picture_playback_drawText 8888 c        108.49     107.64      +0.85   
+0.8% 
               text_16_LCD_FF 8888 c          4.95       4.91      +0.04   
+0.8% 
                text_16_AA_BK 8888 c          3.49       3.46      +0.03   
+0.9% 
      cmap_paint_textToGlyphs 8888 c          4.60       4.54      +0.06   
+1.3% 
      cmap_paint_containsText 8888 c          4.64       4.50      +0.14   
+3.0% 
picture_playback_drawPosTextH 8888 c        120.18     109.45     +10.73   
+8.9% 

X86 results bench_pictures:
              tabl_gspro.skp simple c          4.60       4.67      -0.07   
-1.5% 
            desk_booking.skp simple c          9.26       9.34      -0.08   
-0.9% 
         tabl_deviantart.skp simple c          5.98       6.03      -0.05   
-0.8% 
         desk_forecastio.skp simple c          3.69       3.72      -0.03   
-0.8% 
             tabl_nofolo.skp simple c         16.31      16.43      -0.12   
-0.7% 
          tabl_vnexpress.skp simple c          9.27       9.30      -0.03   
-0.3% 
               desk_espn.skp simple c          7.05       7.07      -0.02   
-0.3% 
                tabl_mlb.skp simple c         10.92      10.95      -0.03   
-0.3% 
            tabl_nytimes.skp simple c          3.81       3.82      -0.01   
-0.3% 
               tabl_digg.skp simple c         30.82      30.90      -0.08   
-0.3% 
               desk_ebay.skp simple c         22.52      22.53      -0.01   
-0.0% 
  desk_googlespreadsheet.skp simple c          4.68       4.68      +0.00   
+0.0% 
 desk_jsfiddlehumperclip.skp simple c          0.83       0.83      +0.00   
+0.0% 
desk_rectangletransition.skp simple c          0.32       0.32      +0.00   
+0.0% 
             desk_sfgate.skp simple c         12.72      12.72      +0.00   
+0.0% 
            desk_weather.skp simple c          7.82       7.82      +0.00   
+0.0% 
       desk_yahooanswers.skp simple c          4.32       4.32      +0.00   
+0.0% 
           desk_facebook.skp simple c         49.68      49.63      +0.05   
+0.1% 
         desk_techcrunch.skp simple c         23.67      23.60      +0.07   
+0.3% 
            desk_twitter.skp simple c          9.02       8.99      +0.03   
+0.3% 
            tabl_sahadan.skp simple c          2.92       2.91      +0.01   
+0.3% 
            desk_blogger.skp simple c         21.63      21.47      +0.16   
+0.7% 
               tabl_hsfi.skp simple c          1.30       1.29      +0.01   
+0.8% 
        desk_pokemonwiki.skp simple c         78.01      77.31      +0.70   
+0.9% 
         desk_mobilenews.skp simple c          9.30       9.20      +0.10   
+1.1% 
          desk_pinterest.skp simple c          2.02       1.99      +0.03   
+1.5% 
           desk_fontwipe.skp simple c          0.38       0.37      +0.01   
+2.6% 


For ARM, (-d nvidia_logan) I get pretty random bench results, going both ways.
It's likely that my measurement setup is a bit unreliable atm.. The
bench_pictures results are consistently not having any impact.

Bench ARM:

RESULT 9
picture_playback_drawPosTextH 8888 c        862.54    2222.03   -1359.49 
-157.6% 
 picture_playback_drawPosText 8888 c       1725.73    1870.70    -144.97   
-8.4% 
            text_16_pos_AA_BK 8888 c          8.47       8.57      -0.10   
-1.2% 
               text_16_LCD_88 8888 c         11.41      11.48      -0.07   
-0.6% 
      cmap_paint_textToGlyphs 8888 c          9.46       9.51      -0.05   
-0.5% 
                text_16_AA_FF 8888 c         10.91      10.96      -0.05   
-0.5% 
    picture_playback_drawText 8888 c        614.57     616.93      -2.36   
-0.4% 
                text_16_AA_BK 8888 c          8.81       8.82      -0.01   
-0.1% 
               text_16_LCD_FF 8888 c         11.03      11.04      -0.01   
-0.1% 
                text_16_AA_88 8888 c         11.47      11.48      -0.01   
-0.1% 
      cmap_paint_containsText 8888 c          9.30       9.26      +0.04   
+0.4% 
               text_16_LCD_BK 8888 c          8.94       8.90      +0.04   
+0.4% 
                text_16_BW_BK 8888 c          3.98       3.96      +0.02   
+0.5% 
                text_16_BW_FF 8888 c          3.98       3.95      +0.03   
+0.8% 
                text_16_BW_88 8888 c          6.15       6.10      +0.05   
+0.8% 
RESULT 10
                text_16_BW_FF 8888 c          3.93       3.96      -0.03   
-0.8% 
                text_16_AA_FF 8888 c         10.14      10.19      -0.05   
-0.5% 
                text_16_BW_BK 8888 c          3.96       3.97      -0.01   
-0.3% 
      cmap_paint_textToGlyphs 8888 c          9.49       9.49      +0.00   
+0.0% 
      cmap_paint_containsText 8888 c          9.27       9.25      +0.02   
+0.2% 
                text_16_BW_88 8888 c          5.86       5.82      +0.04   
+0.7% 
               text_16_LCD_88 8888 c         10.81      10.71      +0.10   
+0.9% 
               text_16_LCD_BK 8888 c          8.42       8.34      +0.08   
+1.0% 
            text_16_pos_AA_BK 8888 c          8.62       8.53      +0.09   
+1.0% 
                text_16_AA_BK 8888 c          8.33       8.24      +0.09   
+1.1% 
picture_playback_drawPosTextH 8888 c       1475.11    1457.98     +17.13   
+1.2% 
    picture_playback_drawText 8888 c        450.14     440.30      +9.84   
+2.2% 
               text_16_LCD_FF 8888 c         10.74      10.27      +0.47   
+4.4% 
                text_16_AA_88 8888 c         11.03      10.51      +0.52   
+4.7% 
 picture_playback_drawPosText 8888 c       2065.00    1679.77    +385.23  
+18.7%

[jvanverth1, 2014-06-12 14:33:01]

lgtm

LGTM + comment

https://codereview.chromium.org/335573002/diff/1/src/core/SkTextMapState.h
File src/core/SkTextMapState.h (right):

https://codereview.chromium.org/335573002/diff/1/src/core/SkTextMapState.h#ne...
src/core/SkTextMapState.h:14: class SkTextMapState {
I think this should be called SkTextMapStateProc, to match SkTextAlignProc.

[jvanverth1, 2014-06-12 14:37:35]

You may need to add Mike to get permission to change the public interface.

[reed1, 2014-06-12 15:01:41]

lgtm

[Kimmo Kinnunen, 2014-06-13 05:40:33]

The CQ bit was checked by kkinnunen@nvidia.com

[commit-bot: I haz the power, 2014-06-13 05:40:37]

CQ is trying da patch. Follow status at
 https://skia-tree-status.appspot.com/cq/kkinnunen@nvidia.com/335573002/20001

[commit-bot: I haz the power, 2014-06-13 06:06:33]

Change committed as cb9a2c8934f009b6ee1ca73d662ac18b285085d9