Bug #9316260
The GL specification indicates that deleting a bound texture has
the side effect of binding the default texture (name=0). This change
replaces all calls to glDeleteTextures() by Caches::deleteTexture()
to properly keep track of texture bindings.
Change-Id: Ifbc60ef433e0f9776a668dd5bd5f0adbc65a77a0
The virtual textures would each have their own values for wrapping
and filtering which could lead to conflict and/or extraneous GL
commands being issued.
Change-Id: I64cb59a03e598f46bf645bd1d30fccfa63a07431
When the Android runtime starts, the system preloads a series of assets
in the Zygote process. These assets are shared across all processes.
Unfortunately, each one of these assets is later uploaded in its own
OpenGL texture, once per process. This wastes memory and generates
unnecessary OpenGL state changes.
This CL introduces an asset server that provides an atlas to all processes.
Note: bitmaps used by skia shaders are *not* sampled from the atlas.
It's an uncommon use case and would require extra texture transforms
in the GL shaders.
WHAT IS THE ASSETS ATLAS
The "assets atlas" is a single, shareable graphic buffer that contains
all the system's preloaded bitmap drawables (this includes 9-patches.)
The atlas is made of two distinct objects: the graphic buffer that
contains the actual pixels and the map which indicates where each
preloaded bitmap can be found in the atlas (essentially a pair of
x and y coordinates.)
HOW IS THE ASSETS ATLAS GENERATED
Because we need to support a wide variety of devices and because it
is easy to change the list of preloaded drawables, the atlas is
generated at runtime, during the startup phase of the system process.
There are several steps that lead to the atlas generation:
1. If the device is booting for the first time, or if the device was
updated, we need to find the best atlas configuration. To do so,
the atlas service tries a number of width, height and algorithm
variations that allows us to pack as many assets as possible while
using as little memory as possible. Once a best configuration is found,
it gets written to disk in /data/system/framework_atlas
2. Given a best configuration (algorithm variant, dimensions and
number of bitmaps that can be packed in the atlas), the atlas service
packs all the preloaded bitmaps into a single graphic buffer object.
3. The packing is done using Skia in a temporary native bitmap. The
Skia bitmap is then copied into the graphic buffer using OpenGL ES
to benefit from texture swizzling.
HOW PROCESSES USE THE ATLAS
Whenever a process' hardware renderer initializes its EGL context,
it queries the atlas service for the graphic buffer and the map.
It is important to remember that both the context and the map will
be valid for the lifetime of the hardware renderer (if the system
process goes down, all apps get killed as well.)
Every time the hardware renderer needs to render a bitmap, it first
checks whether the bitmap can be found in the assets atlas. When
the bitmap is part of the atlas, texture coordinates are remapped
appropriately before rendering.
Change-Id: I8eaecf53e7f6a33d90da3d0047c5ceec89ea3af0
Bug #7353771
This API can be used when scaling large images down to a small size
to get nicer looking results.
Change-Id: If09087eed36077eee5355f6047a3ca67747d7d9e
Some logic depends on a default value of 0, which was not being
assigned.
Issue #7195815 chrome url bar is corrupted
Issue #7190656 Textures corrupted on mr1
Change-Id: I346b7b76e885bf8f04740e711fd88f917a5418c7
This change sets textures filtering to GL_NEAREST by default. GL_LINEAR
filtering is only used when textures are transformed with a scale or
a rotation. This helps save a couple of fps on some GPUs.
Change-Id: I1efaa452c2c79905f00238e54d886a37203a2ac1
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
