0 前言
Canvas是应用渲染离不开的画布，本文对此进行分析。
1 类图
| Canvas | frameworks/base/graphics/java/android/graphics/Canvas.java |
| CompatibleCanvas | frameworks/base/core/java/android/view/Surface.java |
| HardwareCanvas | frameworks/base/core/java/android/view/HardwareCanvas.java |
| GLES20Canvas | frameworks/base/core/java/android/view/GLES20Canvas.java frameworks/base/core/jni/android_view_GLES20Canvas.cpp |
2 案例
（1）详见参考资料[1]。
参考资料
[1]iTOP4412|Android-4.0.3_r1 HardwareRenderer
