android12-release
推荐 Android 12 开机动画代码与流程详解

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1、BootLoader开机图片

一般使用rle格式图片；例如放在splash分区

adb reboot bootloader
fastboot flash splash splash.img
fastboot reboot

2、Kernel开机图片

记录 kernel/drivers/video/msm/msm_fb.c 也是读出根目录下的xx.rle，并显示为开机画面

3、系统启动时（BootAnimation）动画

使用BootAnimation程序显示开机画面，如需修改开机画面，不用修改代码，只需按格式要求做bootanimation.zip包，放在系统的/system/media目录中，或/oem/media、/product/media等目录。

代码路径：frameworks/base/cmds/bootanimation

3.1 bootanimation.zip位置

frameworks/base/cmds/bootanimation/BootAnimation.cpp，例如bootanimation.zip

3.2 bootanimation启动

frameworks/base/cmds/bootanimation/Android.bp
frameworks/base/cmds/bootanimation/bootanim.rc
frameworks/base/cmds/bootanimation/bootanimation_main.cpp
frameworks/base/cmds/bootanimation/BootAnimation.cpp
frameworks/base/cmds/bootanimation/BootAnimationUtil.cpp

SurfaceFlinger进程名：bootanim
bin文件：/system/bin/bootanimation
对应启动入口：/frameworks/base/cmds/bootanimation/bootanimation_main.cpp

bootAnimationDisabled()检测系统属性（debug.sf.nobootanimation、ro.boot.quiescent、ro.bootanim.quiescent.enabled），noBootAnimation 是否启动开机动画。注意init进程在启动bootanimation服务是disable的，不会主动将应用程序bootanimation启动起来。启动bootanimation是从surfaceFlinger这边来启动的

frameworks/base/cmds/bootanimation/bootanimation_main.cpp

int main()
{setpriority(PRIO_PROCESS, 0, ANDROID_PRIORITY_DISPLAY);bool noBootAnimation = bootAnimationDisabled();ALOGI_IF(noBootAnimation,  "boot animation disabled");if (!noBootAnimation) {sp<ProcessState> proc(ProcessState::self());ProcessState::self()->startThreadPool();// create the boot animation object (may take up to 200ms for 2MB zip)sp<BootAnimation> boot = new BootAnimation(audioplay::createAnimationCallbacks());waitForSurfaceFlinger();boot->run("BootAnimation", PRIORITY_DISPLAY);ALOGV("Boot animation set up. Joining pool.");IPCThreadState::self()->joinThreadPool();}return 0;
}

frameworks/base/cmds/bootanimation/BootAnimationUtil.cpp

bool bootAnimationDisabled() {char value[PROPERTY_VALUE_MAX];property_get("debug.sf.nobootanimation", value, "0");if (atoi(value) > 0) {return true;}property_get("ro.boot.quiescent", value, "0");if (atoi(value) > 0) {// Only show the bootanimation for quiescent boots if this system property is set to enabledif (!property_get_bool("ro.bootanim.quiescent.enabled", false)) {return true;}}return false;
}

3.3 SurfaceFlinger启动bootanimation

SurfaceFlinger启动-Android12 初始化时候 mStartPropertySetThread->Start() 在线程中设置property_set("ctl.start", "bootanim")启动开机动画

/frameworks/native/services/surfaceflinger/SurfaceFlinger.cpp
frameworks/native/services/surfaceflinger/StartPropertySetThread.cpp

#include <cutils/properties.h>
#include "StartPropertySetThread.h"namespace android {StartPropertySetThread::StartPropertySetThread(bool timestampPropertyValue):Thread(false), mTimestampPropertyValue(timestampPropertyValue) {}status_t StartPropertySetThread::Start() {return run("SurfaceFlinger::StartPropertySetThread", PRIORITY_NORMAL);
}bool StartPropertySetThread::threadLoop() {// Set property service.sf.present_timestamp, consumer need check its readinessproperty_set(kTimestampProperty, mTimestampPropertyValue ? "1" : "0");// Clear BootAnimation exit flagproperty_set("service.bootanim.exit", "0");property_set("service.bootanim.progress", "0");// Start BootAnimation if not startedproperty_set("ctl.start", "bootanim");// Exit immediatelyreturn false;
}} // namespace android

3.4 播放开机动画playAnimation

• result = android()android原生动画；result = movie()自动动画
• playAnimation(*mAnimation)播放动画；releaseAnimation(mAnimation)释放动画资源
• 播放动画过程：initTexture(frame.map, &w, &h)、drawClock(animation.clockFont, part.clockPosX, part.clockPosY)、drawProgress(lastDisplayedProgress, animation.progressFont, posX, posY)、checkExit()
• checkExit()检测属性"service.bootanim.exit"退出动画

bool BootAnimation::threadLoop() {bool result;// We have no bootanimation file, so we use the stock android logo// animation.if (mZipFileName.isEmpty()) {result = android();} else {result = movie();}mCallbacks->shutdown();eglMakeCurrent(mDisplay, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);eglDestroyContext(mDisplay, mContext);eglDestroySurface(mDisplay, mSurface);mFlingerSurface.clear();mFlingerSurfaceControl.clear();eglTerminate(mDisplay);eglReleaseThread();IPCThreadState::self()->stopProcess();return result;
}

bool BootAnimation::movie() {if (mAnimation == nullptr) {mAnimation = loadAnimation(mZipFileName);}if (mAnimation == nullptr)return false;// mCallbacks->init() may get called recursively,// this loop is needed to get the same resultsfor (const Animation::Part& part : mAnimation->parts) {if (part.animation != nullptr) {mCallbacks->init(part.animation->parts);}}mCallbacks->init(mAnimation->parts);bool anyPartHasClock = false;for (size_t i=0; i < mAnimation->parts.size(); i++) {if(validClock(mAnimation->parts[i])) {anyPartHasClock = true;break;}}if (!anyPartHasClock) {mClockEnabled = false;}// Check if npot textures are supportedmUseNpotTextures = false;String8 gl_extensions;const char* exts = reinterpret_cast<const char*>(glGetString(GL_EXTENSIONS));if (!exts) {glGetError();} else {gl_extensions.setTo(exts);if ((gl_extensions.find("GL_ARB_texture_non_power_of_two") != -1) ||(gl_extensions.find("GL_OES_texture_npot") != -1)) {mUseNpotTextures = true;}}// Blend required to draw time on top of animation frames.glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);glShadeModel(GL_FLAT);glDisable(GL_DITHER);glDisable(GL_SCISSOR_TEST);glDisable(GL_BLEND);glBindTexture(GL_TEXTURE_2D, 0);glEnable(GL_TEXTURE_2D);glTexEnvx(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);glTexParameterx(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);glTexParameterx(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);glTexParameterx(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);glTexParameterx(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);bool clockFontInitialized = false;if (mClockEnabled) {clockFontInitialized =(initFont(&mAnimation->clockFont, CLOCK_FONT_ASSET) == NO_ERROR);mClockEnabled = clockFontInitialized;}initFont(&mAnimation->progressFont, PROGRESS_FONT_ASSET);if (mClockEnabled && !updateIsTimeAccurate()) {mTimeCheckThread = new TimeCheckThread(this);mTimeCheckThread->run("BootAnimation::TimeCheckThread", PRIORITY_NORMAL);}playAnimation(*mAnimation);if (mTimeCheckThread != nullptr) {mTimeCheckThread->requestExit();mTimeCheckThread = nullptr;}if (clockFontInitialized) {glDeleteTextures(1, &mAnimation->clockFont.texture.name);}releaseAnimation(mAnimation);mAnimation = nullptr;return false;
}

bool BootAnimation::playAnimation(const Animation& animation) {const size_t pcount = animation.parts.size();nsecs_t frameDuration = s2ns(1) / animation.fps;SLOGD("%sAnimationShownTiming start time: %" PRId64 "ms", mShuttingDown ? "Shutdown" : "Boot",elapsedRealtime());int fadedFramesCount = 0;int lastDisplayedProgress = 0;for (size_t i=0 ; i<pcount ; i++) {const Animation::Part& part(animation.parts[i]);const size_t fcount = part.frames.size();glBindTexture(GL_TEXTURE_2D, 0);// Handle animation packageif (part.animation != nullptr) {playAnimation(*part.animation);if (exitPending())break;continue; //to next part}// process the part not only while the count allows but also if already fadingfor (int r=0 ; !part.count || r<part.count || fadedFramesCount > 0 ; r++) {if (shouldStopPlayingPart(part, fadedFramesCount, lastDisplayedProgress)) break;mCallbacks->playPart(i, part, r);glClearColor(part.backgroundColor[0],part.backgroundColor[1],part.backgroundColor[2],1.0f);// For the last animation, if we have progress indicator from// the system, display it.int currentProgress = android::base::GetIntProperty(PROGRESS_PROP_NAME, 0);bool displayProgress = animation.progressEnabled &&(i == (pcount -1)) && currentProgress != 0;for (size_t j=0 ; j<fcount ; j++) {if (shouldStopPlayingPart(part, fadedFramesCount, lastDisplayedProgress)) break;processDisplayEvents();const int animationX = (mWidth - animation.width) / 2;const int animationY = (mHeight - animation.height) / 2;const Animation::Frame& frame(part.frames[j]);nsecs_t lastFrame = systemTime();if (r > 0) {glBindTexture(GL_TEXTURE_2D, frame.tid);} else {if (part.count != 1) {glGenTextures(1, &frame.tid);glBindTexture(GL_TEXTURE_2D, frame.tid);glTexParameterx(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);glTexParameterx(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);}int w, h;initTexture(frame.map, &w, &h);}const int xc = animationX + frame.trimX;const int yc = animationY + frame.trimY;Region clearReg(Rect(mWidth, mHeight));clearReg.subtractSelf(Rect(xc, yc, xc+frame.trimWidth, yc+frame.trimHeight));if (!clearReg.isEmpty()) {Region::const_iterator head(clearReg.begin());Region::const_iterator tail(clearReg.end());glEnable(GL_SCISSOR_TEST);while (head != tail) {const Rect& r2(*head++);glScissor(r2.left, mHeight - r2.bottom, r2.width(), r2.height());glClear(GL_COLOR_BUFFER_BIT);}glDisable(GL_SCISSOR_TEST);}// specify the y center as ceiling((mHeight - frame.trimHeight) / 2)// which is equivalent to mHeight - (yc + frame.trimHeight)const int frameDrawY = mHeight - (yc + frame.trimHeight);glDrawTexiOES(xc, frameDrawY, 0, frame.trimWidth, frame.trimHeight);// if the part hasn't been stopped yet then continue fading if necessaryif (exitPending() && part.hasFadingPhase()) {fadeFrame(xc, frameDrawY, frame.trimWidth, frame.trimHeight, part,++fadedFramesCount);if (fadedFramesCount >= part.framesToFadeCount) {fadedFramesCount = MAX_FADED_FRAMES_COUNT; // no more fading}}if (mClockEnabled && mTimeIsAccurate && validClock(part)) {drawClock(animation.clockFont, part.clockPosX, part.clockPosY);}if (displayProgress) {int newProgress = android::base::GetIntProperty(PROGRESS_PROP_NAME, 0);// In case the new progress jumped suddenly, still show an// increment of 1.if (lastDisplayedProgress != 100) {// Artificially sleep 1/10th a second to slow down the animation.usleep(100000);if (lastDisplayedProgress < newProgress) {lastDisplayedProgress++;}}// Put the progress percentage right below the animation.int posY = animation.height / 3;int posX = TEXT_CENTER_VALUE;drawProgress(lastDisplayedProgress, animation.progressFont, posX, posY);}handleViewport(frameDuration);eglSwapBuffers(mDisplay, mSurface);nsecs_t now = systemTime();nsecs_t delay = frameDuration - (now - lastFrame);//SLOGD("%lld, %lld", ns2ms(now - lastFrame), ns2ms(delay));lastFrame = now;if (delay > 0) {struct timespec spec;spec.tv_sec  = (now + delay) / 1000000000;spec.tv_nsec = (now + delay) % 1000000000;int err;do {err = clock_nanosleep(CLOCK_MONOTONIC, TIMER_ABSTIME, &spec, nullptr);} while (err<0 && errno == EINTR);}checkExit();}usleep(part.pause * ns2us(frameDuration));if (exitPending() && !part.count && mCurrentInset >= mTargetInset &&!part.hasFadingPhase()) {if (lastDisplayedProgress != 0 && lastDisplayedProgress != 100) {android::base::SetProperty(PROGRESS_PROP_NAME, "100");continue;}break; // exit the infinite non-fading part when it has been played at least once}}}// Free textures created for looping parts now that the animation is done.for (const Animation::Part& part : animation.parts) {if (part.count != 1) {const size_t fcount = part.frames.size();for (size_t j = 0; j < fcount; j++) {const Animation::Frame& frame(part.frames[j]);glDeleteTextures(1, &frame.tid);}}}return true;
}

3.6 开机动画退出检测

• checkExit()检测属性"service.bootanim.exit"退出动画；在playAnimation方法和android方法中都有一个checkExit方法来负责检查是否退出动画
• WMS中performEnableScreen()设置SystemProperties.set("service.bootanim.exit", "1")

void BootAnimation::checkExit() {// Allow surface flinger to gracefully request shutdownchar value[PROPERTY_VALUE_MAX];property_get(EXIT_PROP_NAME, value, "0");int exitnow = atoi(value);if (exitnow) {requestExit();}
}

private void performEnableScreen() {synchronized (mGlobalLock) {ProtoLog.i(WM_DEBUG_BOOT, "performEnableScreen: mDisplayEnabled=%b"+ " mForceDisplayEnabled=%b" + " mShowingBootMessages=%b"+ " mSystemBooted=%b mOnlyCore=%b. %s", mDisplayEnabled,mForceDisplayEnabled, mShowingBootMessages, mSystemBooted, mOnlyCore,new RuntimeException("here").fillInStackTrace());if (mDisplayEnabled) {return;}if (!mSystemBooted && !mShowingBootMessages) {return;}if (!mShowingBootMessages && !mPolicy.canDismissBootAnimation()) {return;}// Don't enable the screen until all existing windows have been drawn.if (!mForceDisplayEnabled) {if (mBootWaitForWindowsStartTime < 0) {// First time we will start waiting for all windows to be drawn.mBootWaitForWindowsStartTime = SystemClock.elapsedRealtime();}for (int i = mRoot.getChildCount() - 1; i >= 0; i--) {if (mRoot.getChildAt(i).shouldWaitForSystemDecorWindowsOnBoot()) {return;}}long waitTime = SystemClock.elapsedRealtime() - mBootWaitForWindowsStartTime;mBootWaitForWindowsStartTime = -1;if (waitTime > 10) {ProtoLog.i(WM_DEBUG_BOOT,"performEnableScreen: Waited %dms for all windows to be drawn",waitTime);}}if (!mBootAnimationStopped) {Trace.asyncTraceBegin(TRACE_TAG_WINDOW_MANAGER, "Stop bootanim", 0);// stop boot animation// formerly we would just kill the process, but we now ask it to exit so it// can choose where to stop the animation.SystemProperties.set("service.bootanim.exit", "1");mBootAnimationStopped = true;}if (!mForceDisplayEnabled && !checkBootAnimationCompleteLocked()) {ProtoLog.i(WM_DEBUG_BOOT, "performEnableScreen: Waiting for anim complete");return;}try {IBinder surfaceFlinger = ServiceManager.getService("SurfaceFlinger");if (surfaceFlinger != null) {ProtoLog.i(WM_ERROR, "******* TELLING SURFACE FLINGER WE ARE BOOTED!");Parcel data = Parcel.obtain();data.writeInterfaceToken("android.ui.ISurfaceComposer");surfaceFlinger.transact(IBinder.FIRST_CALL_TRANSACTION, // BOOT_FINISHEDdata, null, 0);data.recycle();}} catch (RemoteException ex) {ProtoLog.e(WM_ERROR, "Boot completed: SurfaceFlinger is dead!");}EventLogTags.writeWmBootAnimationDone(SystemClock.uptimeMillis());Trace.asyncTraceEnd(TRACE_TAG_WINDOW_MANAGER, "Stop bootanim", 0);mDisplayEnabled = true;ProtoLog.i(WM_DEBUG_SCREEN_ON, "******************** ENABLING SCREEN!");// Enable input dispatch.mInputManagerCallback.setEventDispatchingLw(mEventDispatchingEnabled);}try {mActivityManager.bootAnimationComplete();} catch (RemoteException e) {}mPolicy.enableScreenAfterBoot();// Make sure the last requested orientation has been applied.updateRotationUnchecked(false, false);
}

3.7 简易时序图

4、bootanimation.zip文件

bootanimation.zip

bootanimation.zip\desc.txt：

1080 2400 5
p 0 5 part0

bootanimation.zip\part0：