Before Android 2.2 (Froyo), all bytecode was interpreted. Froyo introduces a tracing JIT
compiler, which compiles parts of the bytecode to machine code on the fly. This
increases the performance of computationally intensive applications considerably.
Each application running in an instance of the Dalvik VM has a total of 16MB to 24MB of
heap memory available. We’ll have to keep that in mind as we juggle our image and
audio resources.
Skia Graphics Library (Skia): This software renderer for 2D graphics is
used for rendering the UI of Android applications.
OpenGL for Embedded Systems (OpenGL ES): This is the industry
standard for hardware-accelerated graphics rendering. OpenGL ES 1.0
and 1.1 are exposed in Java on all versions of Android. OpenGL ES 2.0,
which brings shaders to the table, is supported from only Android 2.2
(Froyo) onward. It should be mentioned that the Java bindings for
OpenGL ES 2.0 are incomplete and lack a few vital methods. Also, the
emulator and most of the older devices that still make up a considerable
share of the market do not support OpenGL ES 2.0.
转载于:https://www.cnblogs.com/jianglee/archive/2011/05/28/2060460.html