AndroidTV切换系统输出分辨率的一些思考

Android 12 后的一些思考：是否可以使用原生的某些接口实现切换系统分辨率呢？

参考文章：

https://blog.csdn.net/u014535072/article/details/108692559

从源码中看到的可能相关的内容：

 /frameworks/base/services/core/java/com/android/server/display/DisplayManagerService.java

中的方法：

@Override
public void setDisplayProperties(int displayId, boolean hasContent,
float requestedRefreshRate, int requestedMode, float requestedMinRefreshRate,
float requestedMaxRefreshRate, boolean requestedMinimalPostProcessing,
boolean inTraversal) {
setDisplayPropertiesInternal(displayId, hasContent, requestedRefreshRate,
requestedMode, requestedMinRefreshRate, requestedMaxRefreshRate,
requestedMinimalPostProcessing, inTraversal);
}

获取支持的Display mode:

获取Display info的参看

/packages/apps/Launcher3/src/com/android/launcher3/util/DisplayController.java

private final DisplayManager mDM;
mDM = context.getSystemService(DisplayManager.class);
Display display = mDM.getDisplay(DEFAULT_DISPLAY);

基础的Display类

/frameworks/base/core/java/android/view/Display.java

/**
* Returns the active mode of the display.
*/
public Mode getMode() {
synchronized (mLock) {
updateDisplayInfoLocked();
return mDisplayInfo.getMode();
}
}
/**
* Gets the supported modes of this display.
*/
public Mode[] getSupportedModes() {
synchronized (mLock) {
updateDisplayInfoLocked();
final Display.Mode[] modes = mDisplayInfo.supportedModes;
return Arrays.copyOf(modes, modes.length);
}
}

Display::Mode的定义：

http://aospxref.com/android-12.0.0_r3/xref/frameworks/base/core/java/android/view/Display.java#1696

一个例子demo

http://aospxref.com/android-12.0.0_r3/xref/cts/apps/CtsVerifier/src/com/android/cts/verifier/tv/display/ModeSwitchingTestActivity.java#66

DisplayManager displayManager = getSystemService(DisplayManager.class);
Display display = displayManager.getDisplay(Display.DEFAULT_DISPLAY);
List modeList = findTestModes(display);
Display.Mode lastMode = display.getMode();

private List findTestModes(Display display) {
Display.Mode activeMode = display.getMode();
List modeList = new ArrayList<>();
// Find a mode to test refresh rate switch - the mode with smallest refresh rate and
// the same resolution as the active mode
Arrays.stream(display.getSupportedModes())
.filter(mode -> !mode.equals(activeMode))
.filter(mode -> isResolutionEqual(mode, activeMode))
.min(Comparator.comparingDouble(Display.Mode::getRefreshRate))
.ifPresent(modeList::add);
// Find a mode to test seamless mode switch.
if (modeList.size() > 0 && !DisplayUtil.isModeSwitchSeamless(activeMode, modeList.get(0))
&& activeMode.getAlternativeRefreshRates().length > 0) {
Arrays.stream(display.getSupportedModes())
.filter(mode -> !mode.equals(activeMode))
.filter(mode -> DisplayUtil.isModeSwitchSeamless(activeMode, mode))
.findFirst()
.ifPresent(modeList::add);
}
// Find a mode to test resolution switch - the first 16:9 mode with resolution less
// than the active mode.
Arrays.stream(display.getSupportedModes())
.filter(mode -> !mode.equals(activeMode))
.filter(mode -> !isResolutionEqual(mode, activeMode))
.filter(this::is16to9)
.max(Comparator.comparing(Display.Mode::getPhysicalHeight))
.ifPresent(modeList::add);
return modeList;
}


我目前遇到的问题是不是可以直接在apk中加上这一个来通知到 WM 、SurfaceFLinger呢？

private Display.Mode mNextMode;
@Override
public void runTest() {
Window window = mContext.getWindow();
WindowManager.LayoutParams params = window.getAttributes();
params.preferredDisplayModeId = mNextMode.getModeId();
window.setAttributes(params);
}

另一个可能的途径：

 /frameworks/base/core/java/android/view/SurfaceControl.java

/**
* @hide
*/
public static boolean setDesiredDisplayModeSpecs(IBinder displayToken,
DesiredDisplayModeSpecs desiredDisplayModeSpecs) {
if (displayToken == null) {
throw new IllegalArgumentException("displayToken must not be null");
}
if (desiredDisplayModeSpecs == null) {
throw new IllegalArgumentException("desiredDisplayModeSpecs must not be null");
}
if (desiredDisplayModeSpecs.defaultMode <0) {
throw new IllegalArgumentException("defaultMode must be non-negative");
}
return nativeSetDesiredDisplayModeSpecs(displayToken, desiredDisplayModeSpecs);
}

// Verify that this will reapply the desired modes.
verify(mSurfaceControlProxy).setDesiredDisplayModeSpecs(display.token,
new SurfaceControl.DesiredDisplayModeSpecs(
/* baseModeId */ 2,
/* allowGroupSwitching */ false,
/* primaryRange */ 60f, 60f,
/* appRange */ 60f, 60f
));

SurfaceFlinger

void SurfaceFlinger::loadDisplayModes(PhysicalDisplayId displayId, DisplayModes& outModes,
DisplayModePtr& outActiveMode) const {

activeModeHwcId = getHwComposer().getActiveMode(displayId);
}

只有这里去HWC 获取 getActiveMode

/frameworks/base/core/java/android/view/SurfaceControl.java

通知到SurfaceFlinger???

setDisplaySize
--> DisplayState::eDisplaySizeChanged
--> eDisplayTransactionNeeded
--> processDisplayHotplugEventsLocked
--> loadDisplayModes
--> getHwComposer().getActiveMode(displayId);

获取displayToken

private Bitmap captureScreenshot(Rect crop) {
int width = crop.width();
int height = crop.height();
Bitmap screenshot = null;
final Display display = getDefaultDisplay();
final DisplayAddress address = display.getAddress();
if (!(address instanceof DisplayAddress.Physical)) {
Log.e(TAG, "Skipping Screenshot - Default display does not have a physical address: "
+ display);
} else {
final DisplayAddress.Physical physicalAddress = (DisplayAddress.Physical) address;
final IBinder displayToken = SurfaceControl.getPhysicalDisplayToken(
physicalAddress.getPhysicalDisplayId());
final SurfaceControl.DisplayCaptureArgs captureArgs =
new SurfaceControl.DisplayCaptureArgs.Builder(displayToken)
.setSourceCrop(crop)
.setSize(width, height)
.build();
final SurfaceControl.ScreenshotHardwareBuffer screenshotBuffer =
SurfaceControl.captureDisplay(captureArgs);
screenshot = screenshotBuffer == null ? null : screenshotBuffer.asBitmap();
}
return screenshot;
}

心有猛虎，细嗅蔷薇，生活就该无惧无悔

作者：二的次方 出处：https://www.cnblogs.com/roger-yu/p/15997843.html 本文版权归作者和博客园共有，转载必须给出原文链接，并保留此段声明，否则保留追究法律责任的权利