remove some calls to dib

The PDFium source in core/fxge/dib implements a bit-blitting backend.
This code has several disadvantages over a more modern graphics engine:

- no SIMD support
- no GPU support
- limited quality

Further, calling this code locks in the perceived resolution, so that
the output cannot be scaled without additional loss.

By directing all bitmap drawing through 
CFX_SkiaDeviceDriver::StartDIBits, Skia can handle all appropriate
bitmap optimizations.

To that end, SetDIBits and StretchDIBits now call StartDIBits.

Other changes:

Skia's bitmaps are premultiplied. PDF contains bitmaps that are
unpremultiplied. PDFium appears to use premultiplied bitmaps sometimes,
and unpremultiplied bitmaps elsewhere. Add a debug check for
unpremultiplied bits in Skia's driver, and add a utility to premultiply
PDFium's bitmaps' bits.

PDFium supports a 24 bit RGB bitmap padded to a 32 bit word. Set the
high byte so that Skia can treat this as an ARGB bitmap.

Defer the application of the alpha value to the draw call rather than
calling MultiplyAlpha where possible.

Allow the destination bitmap to be alpha 8 or argb 32.

Committed: https://pdfium.googlesource.com/pdfium/+/36e258b475702bdb1a95a88fcebd78b51069c532

[caryclark, 2016-06-02 12:57:41]

Description was changed from

==========
wip; stretch bits clip

BUG=
==========

to

==========
The PDFium source in core/fxge/dib implements a bit-blitting backend. This code
has several disadvantages over a more modern graphics engine:

- no SIMD support
- no GPU support
- limited quality

Further, calling this code locks in the perceived resolution, so that the output
cannot be scaled without additional loss.

By directing all bitmap drawing through CFX_SkiaDeviceDriver::StartDIBits, Skia
can handle all appropriate bitmap optimizations.

To that end, SetDIBits and StretchDIBits now call StartDIBits.

Other changes:

Skia's bitmaps are premultiplied. PDF contains bitmaps that are unpremultiplied.
PDFium appears to use premultiplied bitmaps sometimes, and unpremultiplied
bitmaps elsewhere. Add a debug check for unpremultiplied bits in Skia's driver,
and add a utility to premultiply PDFium's bitmaps' bits.

PDFium supports a 24 bit RGB bitmap padded to a 32 bit word. Set the high byte
so that Skia can treat this as an ARGB bitmap.

Defer the application of the alpha value to the draw call rather than calling
MultiplyAlpha where possible.

Allow the destination bitmap to be alpha 8 or argb 32.

Update Skia's typeface usage.
==========

[caryclark, 2016-06-02 12:58:42]

Description was changed from

==========
The PDFium source in core/fxge/dib implements a bit-blitting backend. This code
has several disadvantages over a more modern graphics engine:

- no SIMD support
- no GPU support
- limited quality

Further, calling this code locks in the perceived resolution, so that the output
cannot be scaled without additional loss.

By directing all bitmap drawing through CFX_SkiaDeviceDriver::StartDIBits, Skia
can handle all appropriate bitmap optimizations.

To that end, SetDIBits and StretchDIBits now call StartDIBits.

Other changes:

Skia's bitmaps are premultiplied. PDF contains bitmaps that are unpremultiplied.
PDFium appears to use premultiplied bitmaps sometimes, and unpremultiplied
bitmaps elsewhere. Add a debug check for unpremultiplied bits in Skia's driver,
and add a utility to premultiply PDFium's bitmaps' bits.

PDFium supports a 24 bit RGB bitmap padded to a 32 bit word. Set the high byte
so that Skia can treat this as an ARGB bitmap.

Defer the application of the alpha value to the draw call rather than calling
MultiplyAlpha where possible.

Allow the destination bitmap to be alpha 8 or argb 32.

Update Skia's typeface usage.
==========

to

==========
The PDFium source in core/fxge/dib implements a bit-blitting backend.
This code has several disadvantages over a more modern graphics engine:

- no SIMD support
- no GPU support
- limited quality

Further, calling this code locks in the perceived resolution, so that
the output cannot be scaled without additional loss.

By directing all bitmap drawing through 
CFX_SkiaDeviceDriver::StartDIBits, Skia can handle all appropriate
bitmap optimizations.

To that end, SetDIBits and StretchDIBits now call StartDIBits.

Other changes:

Skia's bitmaps are premultiplied. PDF contains bitmaps that are
unpremultiplied. PDFium appears to use premultiplied bitmaps sometimes,
and unpremultiplied bitmaps elsewhere. Add a debug check for
unpremultiplied bits in Skia's driver, and add a utility to premultiply
PDFium's bitmaps' bits.

PDFium supports a 24 bit RGB bitmap padded to a 32 bit word. Set the
high byte so that Skia can treat this as an ARGB bitmap.

Defer the application of the alpha value to the draw call rather than
calling MultiplyAlpha where possible.

Allow the destination bitmap to be alpha 8 or argb 32.

Update Skia's typeface usage.
==========

[caryclark, 2016-06-02 15:13:07]

Description was changed from

==========
The PDFium source in core/fxge/dib implements a bit-blitting backend.
This code has several disadvantages over a more modern graphics engine:

- no SIMD support
- no GPU support
- limited quality

Further, calling this code locks in the perceived resolution, so that
the output cannot be scaled without additional loss.

By directing all bitmap drawing through 
CFX_SkiaDeviceDriver::StartDIBits, Skia can handle all appropriate
bitmap optimizations.

To that end, SetDIBits and StretchDIBits now call StartDIBits.

Other changes:

Skia's bitmaps are premultiplied. PDF contains bitmaps that are
unpremultiplied. PDFium appears to use premultiplied bitmaps sometimes,
and unpremultiplied bitmaps elsewhere. Add a debug check for
unpremultiplied bits in Skia's driver, and add a utility to premultiply
PDFium's bitmaps' bits.

PDFium supports a 24 bit RGB bitmap padded to a 32 bit word. Set the
high byte so that Skia can treat this as an ARGB bitmap.

Defer the application of the alpha value to the draw call rather than
calling MultiplyAlpha where possible.

Allow the destination bitmap to be alpha 8 or argb 32.

Update Skia's typeface usage.
==========

to

==========
The PDFium source in core/fxge/dib implements a bit-blitting backend.
This code has several disadvantages over a more modern graphics engine:

- no SIMD support
- no GPU support
- limited quality

Further, calling this code locks in the perceived resolution, so that
the output cannot be scaled without additional loss.

By directing all bitmap drawing through 
CFX_SkiaDeviceDriver::StartDIBits, Skia can handle all appropriate
bitmap optimizations.

To that end, SetDIBits and StretchDIBits now call StartDIBits.

Other changes:

Skia's bitmaps are premultiplied. PDF contains bitmaps that are
unpremultiplied. PDFium appears to use premultiplied bitmaps sometimes,
and unpremultiplied bitmaps elsewhere. Add a debug check for
unpremultiplied bits in Skia's driver, and add a utility to premultiply
PDFium's bitmaps' bits.

PDFium supports a 24 bit RGB bitmap padded to a 32 bit word. Set the
high byte so that Skia can treat this as an ARGB bitmap.

Defer the application of the alpha value to the draw call rather than
calling MultiplyAlpha where possible.

Allow the destination bitmap to be alpha 8 or argb 32.
==========

[caryclark, 2016-06-02 15:15:19]

caryclark@google.com changed reviewers:
+ dsinclair@chromium.org, reed@google.com

[caryclark, 2016-06-02 15:15:54]

The CQ bit was checked by caryclark@google.com to run a CQ dry run

[commit-bot: I haz the power, 2016-06-02 15:16:01]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/2025043002/120001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/2025043002/120001

[commit-bot: I haz the power, 2016-06-02 15:27:10]

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

[commit-bot: I haz the power, 2016-06-02 15:27:11]

Dry run: This issue passed the CQ dry run.

[dsinclair, 2016-06-02 15:37:30]

lgtm w/ nits.

https://codereview.chromium.org/2025043002/diff/120001/core/fpdfapi/fpdf_rend...
File core/fpdfapi/fpdf_render/fpdf_render.cpp (right):

https://codereview.chromium.org/2025043002/diff/120001/core/fpdfapi/fpdf_rend...
core/fpdfapi/fpdf_render/fpdf_render.cpp:818: int blitAlpha = 255;
int32_t?

https://codereview.chromium.org/2025043002/diff/120001/core/fxge/skia/fx_skia...
File core/fxge/skia/fx_skia_device.cpp (right):

https://codereview.chromium.org/2025043002/diff/120001/core/fxge/skia/fx_skia...
core/fxge/skia/fx_skia_device.cpp:1005: (void)this->StartDIBits(pSource, 0xFF,
argb, &m, 0, dummy, alpha_flag,
Should we store this return and use it on line 1009?

https://codereview.chromium.org/2025043002/diff/120001/core/fxge/skia/fx_skia...
core/fxge/skia/fx_skia_device.cpp:1179:
((CFX_SkiaDeviceDriver*)this->GetDeviceDriver())->PreMultiply();
static_cast<CFX_SkiaDeviceDriver*>(this->GetDeviceDriver())->PreMultiply();

[caryclark, 2016-06-02 15:47:43]

https://codereview.chromium.org/2025043002/diff/120001/core/fpdfapi/fpdf_rend...
File core/fpdfapi/fpdf_render/fpdf_render.cpp (right):

https://codereview.chromium.org/2025043002/diff/120001/core/fpdfapi/fpdf_rend...
core/fpdfapi/fpdf_render/fpdf_render.cpp:818: int blitAlpha = 255;
On 2016/06/02 15:37:30, dsinclair wrote:
> int32_t?

Done.

https://codereview.chromium.org/2025043002/diff/120001/core/fxge/skia/fx_skia...
File core/fxge/skia/fx_skia_device.cpp (right):

https://codereview.chromium.org/2025043002/diff/120001/core/fxge/skia/fx_skia...
core/fxge/skia/fx_skia_device.cpp:1005: (void)this->StartDIBits(pSource, 0xFF,
argb, &m, 0, dummy, alpha_flag,
On 2016/06/02 15:37:30, dsinclair wrote:
> Should we store this return and use it on line 1009?

Done.

https://codereview.chromium.org/2025043002/diff/120001/core/fxge/skia/fx_skia...
core/fxge/skia/fx_skia_device.cpp:1179:
((CFX_SkiaDeviceDriver*)this->GetDeviceDriver())->PreMultiply();
On 2016/06/02 15:37:30, dsinclair wrote:
> static_cast<CFX_SkiaDeviceDriver*>(this->GetDeviceDriver())->PreMultiply();

Done.

[caryclark, 2016-06-02 15:47:55]

The CQ bit was checked by caryclark@google.com

[caryclark, 2016-06-02 15:47:55]

The patchset sent to the CQ was uploaded after l-g-t-m from
dsinclair@chromium.org
Link to the patchset: https://codereview.chromium.org/2025043002/#ps140001
(title: "address comments")

[commit-bot: I haz the power, 2016-06-02 15:48:03]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/2025043002/140001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/2025043002/140001

[commit-bot: I haz the power, 2016-06-02 15:59:24]

Description was changed from

==========
The PDFium source in core/fxge/dib implements a bit-blitting backend.
This code has several disadvantages over a more modern graphics engine:

- no SIMD support
- no GPU support
- limited quality

Further, calling this code locks in the perceived resolution, so that
the output cannot be scaled without additional loss.

By directing all bitmap drawing through 
CFX_SkiaDeviceDriver::StartDIBits, Skia can handle all appropriate
bitmap optimizations.

To that end, SetDIBits and StretchDIBits now call StartDIBits.

Other changes:

Skia's bitmaps are premultiplied. PDF contains bitmaps that are
unpremultiplied. PDFium appears to use premultiplied bitmaps sometimes,
and unpremultiplied bitmaps elsewhere. Add a debug check for
unpremultiplied bits in Skia's driver, and add a utility to premultiply
PDFium's bitmaps' bits.

PDFium supports a 24 bit RGB bitmap padded to a 32 bit word. Set the
high byte so that Skia can treat this as an ARGB bitmap.

Defer the application of the alpha value to the draw call rather than
calling MultiplyAlpha where possible.

Allow the destination bitmap to be alpha 8 or argb 32.
==========

to

==========
The PDFium source in core/fxge/dib implements a bit-blitting backend.
This code has several disadvantages over a more modern graphics engine:

- no SIMD support
- no GPU support
- limited quality

Further, calling this code locks in the perceived resolution, so that
the output cannot be scaled without additional loss.

By directing all bitmap drawing through 
CFX_SkiaDeviceDriver::StartDIBits, Skia can handle all appropriate
bitmap optimizations.

To that end, SetDIBits and StretchDIBits now call StartDIBits.

Other changes:

Skia's bitmaps are premultiplied. PDF contains bitmaps that are
unpremultiplied. PDFium appears to use premultiplied bitmaps sometimes,
and unpremultiplied bitmaps elsewhere. Add a debug check for
unpremultiplied bits in Skia's driver, and add a utility to premultiply
PDFium's bitmaps' bits.

PDFium supports a 24 bit RGB bitmap padded to a 32 bit word. Set the
high byte so that Skia can treat this as an ARGB bitmap.

Defer the application of the alpha value to the draw call rather than
calling MultiplyAlpha where possible.

Allow the destination bitmap to be alpha 8 or argb 32.

Committed:
https://pdfium.googlesource.com/pdfium/+/36e258b475702bdb1a95a88fcebd78b51069...
==========

[commit-bot: I haz the power, 2016-06-02 15:59:25]

Committed patchset #8 (id:140001) as
https://pdfium.googlesource.com/pdfium/+/36e258b475702bdb1a95a88fcebd78b51069...