History log of /frameworks/base/libs/hwui/Vertex.h
Revision Date Author Comments (<<< Hide modified files) (Show modified files >>>)
1bcacfdcab0eaa0cee92bd7f5a1b5e271dd68e52 03-Nov-2017 John Reck <jreck@google.com> Format the world (or just HWUI)

Test: No code changes, just ran through clang-format
Change-Id: Id23aa4ec7eebc0446fe3a30260f33e7fd455bb8c
/frameworks/base/libs/hwui/Vertex.h
253f2c213f6ecda63b6872aee77bd30d5ec07c82 29-Sep-2016 Romain Guy <romainguy@google.com> Linear blending, step 1

NOTE: Linear blending is currently disabled in this CL as the
feature is still a work in progress

Android currently performs all blending (any kind of linear math
on colors really) on gamma-encoded colors. Since Android assumes
that the default color space is sRGB, all bitmaps and colors
are encoded with the sRGB Opto-Electronic Conversion Function
(OECF, which can be approximated with a power function). Since
the power curve is not linear, our linear math is incorrect.
The result is that we generate colors that tend to be too dark;
this affects blending but also anti-aliasing, gradients, blurs,
etc.

The solution is to convert gamma-encoded colors back to linear
space before doing any math on them, using the sRGB Electo-Optical
Conversion Function (EOCF). This is achieved in different
ways in different parts of the pipeline:

- Using hardware conversions when sampling from OpenGL textures
or writing into OpenGL frame buffers
- Using software conversion functions, to translate app-supplied
colors to and from sRGB
- Using Skia's color spaces

Any type of processing on colors must roughly ollow these steps:

[sRGB input]->EOCF->[linear data]->[processing]->OECF->[sRGB output]

For the sRGB color space, the conversion functions are defined as
follows:

OECF(linear) :=
linear <= 0.0031308 ? linear * 12.92 : (pow(linear, 1/2.4) * 1.055) - 0.055

EOCF(srgb) :=
srgb <= 0.04045 ? srgb / 12.92 : pow((srgb + 0.055) / 1.055, 2.4)

The EOCF is simply the reciprocal of the OECF.
While it is highly recommended to use the exact sRGB conversion
functions everywhere possible, it is sometimes useful or beneficial
to rely on approximations:

- pow(x,2.2) and pow(x,1/2.2)
- x^2 and sqrt(x)

The latter is particularly useful in fragment shaders (for instance
to apply dithering in sRGB space), especially if the sqrt() can be
replaced with an inversesqrt().

Here is a fairly exhaustive list of modifications implemented
in this CL:

- Set TARGET_ENABLE_LINEAR_BLENDING := false in BoardConfig.mk
to disable linear blending. This is only for GLES 2.0 GPUs
with no hardware sRGB support. This flag is currently assumed
to be false (see note above)
- sRGB writes are disabled when entering a functor (WebView).
This will need to be fixed at some point
- Skia bitmaps are created with the sRGB color space
- Bitmaps using a 565 config are expanded to 888
- Linear blending is disabled when entering a functor
- External textures are not properly sampled (see below)
- Gradients are interpolated in linear space
- Texture-based dithering was replaced with analytical dithering
- Dithering is done in the quantization color space, which is
why we must do EOCF(OECF(color)+dither)
- Text is now gamma corrected differently depending on the luminance
of the source pixel. The asumption is that a bright pixel will be
blended on a dark background and the other way around. The source
alpha is gamma corrected to thicken dark on bright and thin
bright on dark to match the intended design of fonts. This also
matches the behavior of popular design/drawing applications
- Removed the asset atlas. It did not contain anything useful and
could not be sampled in sRGB without a yet-to-be-defined GL
extension
- The last column of color matrices is converted to linear space
because its value are added to linear colors

Missing features:
- Resource qualifier?
- Regeneration of goldeng images for automated tests
- Handle alpha8/grey8 properly
- Disable sRGB write for layers with external textures

Test: Manual testing while work in progress
Bug: 29940137

Change-Id: I6a07b15ab49b554377cd33a36b6d9971a15e9a0b
/frameworks/base/libs/hwui/Vertex.h
272a685f17cc4828257e521a6f62b7b17870f75e 30-Jul-2015 John Reck <jreck@google.com> Replace most usages of utils/Vector.h

Change-Id: I540d1b3523244d6c71fc52d6fb30555271c25644
/frameworks/base/libs/hwui/Vertex.h
922d3a7f6f8c1c05a996ee3e91e8cbadfff560c9 14-Feb-2015 Chris Craik <ccraik@google.com> Glop SkiaShader support

Change-Id: I894a0b62701bd02367ab970813e4c332147351a2
/frameworks/base/libs/hwui/Vertex.h
0519c810a56bded1284fcb2ae40f438878c6585f 11-Feb-2015 Chris Craik <ccraik@google.com> Glop Bitmap and RoundRect clipping support

Change-Id: I4577546a5d2e5f084cc03f39a89db9231b8111ee
/frameworks/base/libs/hwui/Vertex.h
a9fc9b20da43b0e5d01b10097d6f2e6fafcd6626 22-Jan-2015 Rob Tsuk <robtsuk@google.com> Ensure compatible layout for vertices

Require that these structs have standard layout, which is what we need
to pass them to OpenGL. Inheritence with data members violates the
rules for standard layout so I re-implemented them using templates to
share the code and putting all the data members in each struct.

Change-Id: I19cd0e5518728f2d3e0993b17d15fce7be7e0edb
/frameworks/base/libs/hwui/Vertex.h
51d6a3db97bdd5315f1a17a4b447d10a92217b98 23-Dec-2014 Chris Craik <ccraik@google.com> Cleanup various clang warnings, use unique_ptrs in several places

Change-Id: I347904b25e51fcc7de14b1e72f1acd0f6ba26f3f
/frameworks/base/libs/hwui/Vertex.h
1aa5d2d7068147ff781cfe911a93f01593a68c79 24-Jul-2014 John Reck <jreck@google.com> Fix ALL compile warnings

All warnings/errors fixed for GCC & Clang

Change-Id: I2ece3a136a5ae97a9acc3069537ed986238b5fd3
/frameworks/base/libs/hwui/Vertex.h
564acf7c9bff822f608cda0d5df0a64a9f9aaefd 03-Jan-2014 Chris Craik <ccraik@google.com> Fix Clang warnings/errors

Fix several build warnings (struct != class, int != size_t) and errors
(variable leng non-POD arrays).

Change-Id: I70b4e784365514303d8954bfcb1f39d7c22c1321
/frameworks/base/libs/hwui/Vertex.h
2765c0b71679b5762ed72610e8310abd6d071b96 18-Sep-2013 Chris Craik <ccraik@google.com> resolved conflicts for merge of d97303a7 to master

Change-Id: I29e2e64e0ec241675762482cbe5c5e9dc58adca6
32f05e343c5ffb17f3235942bcda651bd3b9f1d6 18-Sep-2013 Chris Craik <ccraik@google.com> Conservatively estimate geometry bounds

bug:10761696

Avoids a case where a rect with top coordinate of (e.g.) 0.51f is
assumed to not draw in the first row of pixels, which leads to it not
being clipped. Since rounding can cause it to render in this first
pixel anyway, we very slightly expand geometry bounds.

Now, in ambiguous cases, the geometry bounds are expanded so clipping
is more likely to happen.

Change-Id: I119b7c7720de07bac1634549724ffb63935567fc
/frameworks/base/libs/hwui/Vertex.h
3380cfdc77100e87aa8390386ccf390834dea171 16-Aug-2013 Romain Guy <romainguy@google.com> Replace float arrays with readable names

Change-Id: I32a8be560b60a4ac5cbee2fec4574b2c5df9f825
/frameworks/base/libs/hwui/Vertex.h
6d29c8d5218cac0fb35f3b7c253f2bdebd44f15a 09-May-2013 Chris Craik <ccraik@google.com> Add tessellation path for points

bug:4351353
bug:8185479

Point tessellation is similar to line special case, except that we
only tessellate one point (as a circle or rect) and duplicate it
across other instances.

Additionally:

Fixes square caps for AA=false lines

Cleanup in CanvasCompare, disabling interpolation on zoomed-in
comparison view

Change-Id: I0756fcc4b20f77878fed0d8057297c80e82ed9dc
/frameworks/base/libs/hwui/Vertex.h
ff316ec7a76e52572a2e89b691e6b3bba0cafba3 14-Feb-2013 Romain Guy <romainguy@google.com> Implement support for drawBitmapMesh's colors array

Change-Id: I3d901f6267c2918771ac30ff55c8d80c3ab5b725
/frameworks/base/libs/hwui/Vertex.h
65cd612face362d054a85d0f7e5881c59cd523be 11-Dec-2012 Chris Craik <ccraik@google.com> Add cap tessellation support

bug:7117155
bug:8114304

Currently used for lines (with and without AA) and arcs with useCenter=false

Also removes 0.375, 0.375 offset for AA lines

Change-Id: Ic8ace418739344db1e2814edf65253fe7448b0b0
/frameworks/base/libs/hwui/Vertex.h
99585adeb4167ca357a72eb866f34c1af944f4b9 03-May-2011 Chet Haase <chet@google.com> Line endcaps for AA lines are now antialiased.

Also fixed other minor issues with AA and line rendering.

Change-Id: Icd4638d27c70e2ee0f28b5d9a2b97d8b29e8ac4d
/frameworks/base/libs/hwui/Vertex.h
5b0200bd47e8a9a4dc8d2e6c3a110d522b30bf82 14-Apr-2011 Chet Haase <chet@google.com> Enable anti-aliasing for hw-accelerated lines

Draw anti-aliased lines with OpenGL by constructing a quad with
a border that fades out (to mimic fragment coverage).

Change-Id: Ib81a3e62d663acdf1b46b401ac4aa7ee9855cc7e
/frameworks/base/libs/hwui/Vertex.h
5b3b35296e8b2c8d3f07d32bb645d5414db41a1d 28-Oct-2010 Romain Guy <romainguy@google.com> Optimize FBO drawing with regions.
This optimization is currently disabled until Launcher is
modified to take advantage of it. The optimization can be
enabled by turning on RENDER_LAYERS_AS_REGIONS in the
OpenGLRenderer.h file.

Change-Id: I2fdf59d0f4dc690a3d7f712173ab8db3848b27b1
/frameworks/base/libs/hwui/Vertex.h
ac670c0433d19397d4e36ced2110475b6f54fe26 28-Jul-2010 Romain Guy <romainguy@google.com> Generate shaders to cover all possible cases.

With this change, all the vertex and fragment shaders used by the GL
renderer are now generated based on a program description supplied
by the caller. This allows the renderer to generate a large number
of shaders without having to write all the possible combinations by
hand. The generated shaders are stored in a program cache.

Change-Id: If54d286e77ae021c724d42090da476df12a18ebb
/frameworks/base/libs/hwui/Vertex.h
82ba814ca0dea659be2cc6523bc0137679d961ce 09-Jul-2010 Romain Guy <romainguy@google.com> Optimize blending state changes.

Change-Id: I7c22a8aecccb8b5abfcf7243f049a4ef3cf3979a
/frameworks/base/libs/hwui/Vertex.h
f7f93556c8fcc640ab5adef79d021a80a72a645a 09-Jul-2010 Romain Guy <romainguy@google.com> Draw n-patches using OpenGL.

Currently only tested with title bars and buttons.

Change-Id: I8263a9281898dc0e943b1b8412827fe55639b9d6
/frameworks/base/libs/hwui/Vertex.h