Use Color Processor for color bitmap text draws on gpu.

Use Color Processor for color bitmap text draws on gpu.

This change is here since previously color bitmap text was rendered using a
geometry processor in the coverage stage. The problem with this is that we
cannot correctly do xfer modes with this method. So I now make color bitmap text
draw using a color stage in the same was as a draw bitmap call.

One issue that arrises from this fix is that we end up adding this final color
processor after any previous color processors. Thus if we have a custom blend
implemented as a color processor it will be before this text one and we won't
blend correctly. This issue will get fixed once an xfer processor is fully
implemented. I have hacked a test locally to show that if we can add the text
color processor to the begining of the color stages we do blend correctly in all
cases (so the xfer processor will be a fix).

BUG=skia:

Committed: https://skia.googlesource.com/skia/+/ed3af6648ffe1044d6fb3f6deac53711cb1280c8

[egdaniel, 2014-10-30 14:54:28]

egdaniel@google.com changed reviewers:
+ bsalomon@google.com, jvanverth@google.com

[bsalomon, 2014-10-30 15:31:11]

lgtm w/ minor suggestions.

https://codereview.chromium.org/689923004/diff/20001/src/gpu/GrBitmapTextCont...
File src/gpu/GrBitmapTextContext.cpp (right):

https://codereview.chromium.org/689923004/diff/20001/src/gpu/GrBitmapTextCont...
src/gpu/GrBitmapTextContext.cpp:45: extern const GrVertexAttrib
gTextVertexWithLCAttribs[] = {
gBmpTextVertexAttribs?

https://codereview.chromium.org/689923004/diff/20001/src/gpu/GrBitmapTextCont...
src/gpu/GrBitmapTextContext.cpp:570: if (kARGB_GrMaskFormat != fCurrMaskFormat)
{
Switch the sense of this?  Seems easier to read

if (something) { do-for-something } else { do-for-other-cases }

[jvanverth1, 2014-10-30 18:19:43]

More comments:

https://codereview.chromium.org/689923004/diff/20001/src/gpu/GrBitmapTextCont...
File src/gpu/GrBitmapTextContext.cpp (right):

https://codereview.chromium.org/689923004/diff/20001/src/gpu/GrBitmapTextCont...
src/gpu/GrBitmapTextContext.cpp:45: extern const GrVertexAttrib
gTextVertexWithLCAttribs[] = {
On 2014/10/30 15:31:11, bsalomon wrote:
> gBmpTextVertexAttribs?

I think it's more consistent the way it is.

https://codereview.chromium.org/689923004/diff/20001/src/gpu/GrBitmapTextCont...
src/gpu/GrBitmapTextContext.cpp:583: matrix,
I think you can use SkMatrix::I() instead of having to create a new one and call
reset().

[egdaniel, 2014-10-30 19:22:20]

https://codereview.chromium.org/689923004/diff/20001/src/gpu/GrBitmapTextCont...
File src/gpu/GrBitmapTextContext.cpp (right):

https://codereview.chromium.org/689923004/diff/20001/src/gpu/GrBitmapTextCont...
src/gpu/GrBitmapTextContext.cpp:45: extern const GrVertexAttrib
gTextVertexWithLCAttribs[] = {
On 2014/10/30 18:19:43, jvanverth1 wrote:
> On 2014/10/30 15:31:11, bsalomon wrote:
> > gBmpTextVertexAttribs?
> 
> I think it's more consistent the way it is.

I'm in agreement with jim. The way the old names were set up was to describe
what is in the VA array. For example gTextVertexWithColorAttribs contains Color
attribs (but is actually used for grey scale).

gBmpTextVertexAttribs seems even more vague since technically all of these are
bitmap text.

If we want to describe use, we can change them all to:

gLCDTextVertexAttribs
gColorTextVertexAttribs
gBWTextVertexAttribs

[bsalomon, 2014-10-30 19:51:01]

On 2014/10/30 19:22:20, egdaniel wrote:
>
https://codereview.chromium.org/689923004/diff/20001/src/gpu/GrBitmapTextCont...
> File src/gpu/GrBitmapTextContext.cpp (right):
> 
>
https://codereview.chromium.org/689923004/diff/20001/src/gpu/GrBitmapTextCont...
> src/gpu/GrBitmapTextContext.cpp:45: extern const GrVertexAttrib
> gTextVertexWithLCAttribs[] = {
> On 2014/10/30 18:19:43, jvanverth1 wrote:
> > On 2014/10/30 15:31:11, bsalomon wrote:
> > > gBmpTextVertexAttribs?
> > 
> > I think it's more consistent the way it is.
> 
> I'm in agreement with jim. The way the old names were set up was to describe
> what is in the VA array. For example gTextVertexWithColorAttribs contains
Color
> attribs (but is actually used for grey scale).
> 
> gBmpTextVertexAttribs seems even more vague since technically all of these are
> bitmap text.
> 
> If we want to describe use, we can change them all to:
> 
> gLCDTextVertexAttribs
> gColorTextVertexAttribs
> gBWTextVertexAttribs

My thought was that someone reading this code is likely interested in what
happens with bmp glyphs (or lcd glyphs, ...) and in general using names based on
the glyph type might make it easier since the different structs and branches are
spread out through out the file. But I don't feel very strongly, so feel free to
ignore.

[egdaniel, 2014-10-31 13:11:35]

The CQ bit was checked by egdaniel@google.com

[commit-bot: I haz the power, 2014-10-31 13:12:24]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/689923004/60001

[commit-bot: I haz the power, 2014-10-31 13:55:52]

Committed patchset #4 (id:60001) as ed3af6648ffe1044d6fb3f6deac53711cb1280c8