Some improvements to LATC compression

Some improvements to LATC compression

Committed: https://skia.googlesource.com/skia/+/eecc35f988662f4fa82693ad36e908d637a7d3c1

[bsalomon, 2014-06-19 19:19:06]

https://codereview.chromium.org/347673002/diff/1/src/utils/SkTextureCompresso...
File src/utils/SkTextureCompressor.cpp (right):

https://codereview.chromium.org/347673002/diff/1/src/utils/SkTextureCompresso...
src/utils/SkTextureCompressor.cpp:75: return pixel == 0 || pixel == 255;
we usually write "<rvalue> == <lvalue>"

https://codereview.chromium.org/347673002/diff/1/src/utils/SkTextureCompresso...
src/utils/SkTextureCompressor.cpp:182: static uint64_t compressBlock(const
uint8_t pixels[]) {
our (mot consistently enforced) naming convention is to call this
compress_block. similar for other functions in here.

https://codereview.chromium.org/347673002/diff/1/src/utils/SkTextureCompresso...
src/utils/SkTextureCompressor.cpp:285: int blocksX = width / kLATCBlockSize;
Are the width and height always multiples of the blocksize? Or should the caller
have already checked that?

[krajcevski, 2014-06-19 20:56:56]

https://codereview.chromium.org/347673002/diff/1/src/utils/SkTextureCompresso...
File src/utils/SkTextureCompressor.cpp (right):

https://codereview.chromium.org/347673002/diff/1/src/utils/SkTextureCompresso...
src/utils/SkTextureCompressor.cpp:75: return pixel == 0 || pixel == 255;
On 2014/06/19 19:19:05, bsalomon wrote:
> we usually write "<rvalue> == <lvalue>"

Done.

https://codereview.chromium.org/347673002/diff/1/src/utils/SkTextureCompresso...
src/utils/SkTextureCompressor.cpp:182: static uint64_t compressBlock(const
uint8_t pixels[]) {
On 2014/06/19 19:19:05, bsalomon wrote:
> our (mot consistently enforced) naming convention is to call this
> compress_block. similar for other functions in here.

Done.

https://codereview.chromium.org/347673002/diff/1/src/utils/SkTextureCompresso...
src/utils/SkTextureCompressor.cpp:285: int blocksX = width / kLATCBlockSize;
On 2014/06/19 19:19:05, bsalomon wrote:
> Are the width and height always multiples of the blocksize? Or should the
caller
> have already checked that?

I check that the width/height are the proper size when I do the compression. The
only reason we'd need checks here is to make sure that the allocation of data is
a sane number (since it will fail in the compressor if the dimensions are off).

[bsalomon, 2014-06-20 14:11:04]

lgtm

[krajcevski, 2014-06-20 17:04:59]

The CQ bit was checked by krajcevski@google.com

[commit-bot: I haz the power, 2014-06-20 17:05:31]

CQ is trying da patch. Follow status at
 https://skia-tree-status.appspot.com/cq/krajcevski@google.com/347673002/20001

[commit-bot: I haz the power, 2014-06-20 17:09:41]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  Build-Mac10.8-Clang-x86-Release-Trybot on tryserver.skia
(http://108.170.220.76:10117/builders/Build-Mac10.8-Clang-x86-Release-Trybot/b...)
  Build-Mac10.8-Clang-x86_64-Release-Trybot on tryserver.skia
(http://108.170.220.76:10117/builders/Build-Mac10.8-Clang-x86_64-Release-Trybo...)
  Build-Ubuntu13.10-Clang-x86_64-Debug-Trybot on tryserver.skia
(http://108.170.220.76:10117/builders/Build-Ubuntu13.10-Clang-x86_64-Debug-Try...)
  Build-Ubuntu13.10-GCC4.8-Arm7-Debug-Android-Trybot on tryserver.skia
(http://108.170.220.76:10117/builders/Build-Ubuntu13.10-GCC4.8-Arm7-Debug-Andr...)
  Build-Ubuntu13.10-GCC4.8-x86_64-Release-Trybot on tryserver.skia
(http://108.170.220.76:10117/builders/Build-Ubuntu13.10-GCC4.8-x86_64-Release-...)
  Build-Win7-VS2010-x86-Debug-Trybot on tryserver.skia
(http://108.170.220.76:10117/builders/Build-Win7-VS2010-x86-Debug-Trybot/build...)
  Test-Ubuntu13.10-ShuttleA-NoGPU-x86_64-Debug-Trybot on tryserver.skia
(http://108.170.220.120:10117/builders/Test-Ubuntu13.10-ShuttleA-NoGPU-x86_64-...)

[commit-bot: I haz the power, 2014-06-20 17:11:51]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-06-20 17:11:51]

Try jobs failed on following builders:
  Build-Ubuntu13.10-GCC4.8-Arm7-Debug-Android-Trybot on tryserver.skia
(http://108.170.220.76:10117/builders/Build-Ubuntu13.10-GCC4.8-Arm7-Debug-Andr...)

[krajcevski, 2014-06-20 18:22:18]

The CQ bit was checked by krajcevski@google.com

[commit-bot: I haz the power, 2014-06-20 18:28:15]

CQ is trying da patch. Follow status at
 https://skia-tree-status.appspot.com/cq/krajcevski@google.com/347673002/40001

[commit-bot: I haz the power, 2014-06-20 18:43:03]

Change committed as eecc35f988662f4fa82693ad36e908d637a7d3c1