mWin.mShownPosition为最终window的位置,计算过程主要参考了app transition动画,屏幕旋转动画,attach的window的动画,目标墙纸的动画进行计算,最终计算出动画窗口的位置,大小alpha值,函数很简单主要使用了一些线性代数的矩阵变换,只是简单的缩放平移旋转操作.
void computeShownFrameLocked() {
final boolean selfTransformation = mHasLocalTransformation;
Transformation attachedTransformation =
(mAttachedWinAnimator != null && mAttachedWinAnimator.mHasLocalTransformation)
? mAttachedWinAnimator.mTransformation : null;
Transformation appTransformation = (mAppAnimator != null && mAppAnimator.hasTransformation)
? mAppAnimator.transformation : null;
//1 对壁纸窗口的处理,先计算出目标窗口的appTransformation,attachedTransformation
// Wallpapers are animated based on the "real" window they
// are currently targeting.
final WindowState wallpaperTarget = mWallpaperControllerLocked.getWallpaperTarget();
if (mIsWallpaper && wallpaperTarget != null && mService.mAnimateWallpaperWithTarget) {
final WindowStateAnimator wallpaperAnimator = wallpaperTarget.mWinAnimator;
if (wallpaperAnimator.mHasLocalTransformation &&
wallpaperAnimator.mAnimation != null &&
!wallpaperAnimator.mAnimation.getDetachWallpaper()) {
attachedTransformation = wallpaperAnimator.mTransformation;
if (DEBUG_WALLPAPER && attachedTransformation != null) {
Slog.v(TAG, "WP target attached xform: " + attachedTransformation);
}
}
final AppWindowAnimator wpAppAnimator = wallpaperTarget.mAppToken == null ?
null : wallpaperTarget.mAppToken.mAppAnimator;
if (wpAppAnimator != null && wpAppAnimator.hasTransformation
&& wpAppAnimator.animation != null
&& !wpAppAnimator.animation.getDetachWallpaper()) {
appTransformation = wpAppAnimator.transformation;
if (DEBUG_WALLPAPER && appTransformation != null) {
Slog.v(TAG, "WP target app xform: " + appTransformation);
}
}
}
final int displayId = mWin.getDisplayId();
final ScreenRotationAnimation screenRotationAnimation =
mAnimator.getScreenRotationAnimationLocked(displayId);
final boolean screenAnimation =
screenRotationAnimation != null && screenRotationAnimation.isAnimating();
// 2 自己有动画或者父窗口父appwindow包含动画,更新坐标
mHasClipRect = false;
if (selfTransformation || attachedTransformation != null
|| appTransformation != null || screenAnimation) {
// cache often used attributes locally
final Rect frame = mWin.mFrame;
final float tmpFloats[] = mService.mTmpFloats;
final Matrix tmpMatrix = mWin.mTmpMatrix;
// 3 转屏的时候读窗口进行缩小,防止出现错乱的效果
// Compute the desired transformation.
if (screenAnimation && screenRotationAnimation.isRotating()) {
// If we are doing a screen animation, the global rotation
// applied to windows can result in windows that are carefully
// aligned with each other to slightly separate, allowing you
// to see what is behind them. An unsightly mess. This...
// thing... magically makes it call good: scale each window
// slightly (two pixels larger in each dimension, from the
// window's center).
final float w = frame.width();
final float h = frame.height();
if (w>=1 && h>=1) {
tmpMatrix.setScale(1 + 2/w, 1 + 2/h, w/2, h/2);
} else {
tmpMatrix.reset();
}
} else {
tmpMatrix.reset();
}
//4 添加窗口缩放
tmpMatrix.postScale(mWin.mGlobalScale, mWin.mGlobalScale);
if (selfTransformation) { //5 点乘 window动画矩阵
tmpMatrix.postConcat(mTransformation.getMatrix());
}
if (attachedTransformation != null) { //6 点乘attach 的window矩阵
tmpMatrix.postConcat(attachedTransformation.getMatrix());
}
if (appTransformation != null) { // 7 点乘appwindow动画
tmpMatrix.postConcat(appTransformation.getMatrix());
}
//7 平移动画
// The translation that applies the position of the window needs to be applied at the
// end in case that other translations include scaling. Otherwise the scaling will
// affect this translation. But it needs to be set before the screen rotation animation
// so the pivot point is at the center of the screen for all windows.
tmpMatrix.postTranslate(frame.left + mWin.mXOffset, frame.top + mWin.mYOffset);
if (screenAnimation) { //8 屏幕旋转矩阵,注意是进入的动画
tmpMatrix.postConcat(screenRotationAnimation.getEnterTransformation().getMatrix());
}
//TODO (multidisplay): Magnification is supported only for the default display.
if (mService.mAccessibilityController != null && displayId == DEFAULT_DISPLAY) {
MagnificationSpec spec = mService.mAccessibilityController
.getMagnificationSpecForWindowLocked(mWin);
if (spec != null && !spec.isNop()) {
tmpMatrix.postScale(spec.scale, spec.scale);
tmpMatrix.postTranslate(spec.offsetX, spec.offsetY);
}
}
// "convert" it into SurfaceFlinger's format
// (a 2x2 matrix + an offset)
// Here we must not transform the position of the surface
// since it is already included in the transformation.
//Slog.i(TAG_WM, "Transform: " + matrix);
mHaveMatrix = true;
tmpMatrix.getValues(tmpFloats);
mDsDx = tmpFloats[Matrix.MSCALE_X];
mDtDx = tmpFloats[Matrix.MSKEW_Y];
mDsDy = tmpFloats[Matrix.MSKEW_X];
mDtDy = tmpFloats[Matrix.MSCALE_Y];
float x = tmpFloats[Matrix.MTRANS_X];
float y = tmpFloats[Matrix.MTRANS_Y];
mWin.mShownPosition.set(Math.round(x), Math.round(y)); //9变换后的x坐标y坐标
10 alpha值的计算
// Now set the alpha... but because our current hardware
// can't do alpha transformation on a non-opaque surface,
// turn it off if we are running an animation that is also
// transforming since it is more important to have that
// animation be smooth.
mShownAlpha = mAlpha;
if (!mService.mLimitedAlphaCompositing
|| (!PixelFormat.formatHasAlpha(mWin.mAttrs.format)
|| (mWin.isIdentityMatrix(mDsDx, mDtDx, mDsDy, mDtDy)
&& x == frame.left && y == frame.top))) {
//Slog.i(TAG_WM, "Applying alpha transform");
if (selfTransformation) {
mShownAlpha *= mTransformation.getAlpha();
}
if (attachedTransformation != null) {
mShownAlpha *= attachedTransformation.getAlpha();
}
if (appTransformation != null) {
mShownAlpha *= appTransformation.getAlpha();
if (appTransformation.hasClipRect()) {
mClipRect.set(appTransformation.getClipRect());
mHasClipRect = true;
// The app transformation clip will be in the coordinate space of the main
// activity window, which the animation correctly assumes will be placed at
// (0,0)+(insets) relative to the containing frame. This isn't necessarily
// true for child windows though which can have an arbitrary frame position
// relative to their containing frame. We need to offset the difference
// between the containing frame as used to calculate the crop and our
// bounds to compensate for this.
if (mWin.layoutInParentFrame()) {
mClipRect.offset( (mWin.mContainingFrame.left - mWin.mFrame.left),
mWin.mContainingFrame.top - mWin.mFrame.top );
}
}
}
if (screenAnimation) {
mShownAlpha *= screenRotationAnimation.getEnterTransformation().getAlpha();
}
} else {
//Slog.i(TAG_WM, "Not applying alpha transform");
}
if ((DEBUG_SURFACE_TRACE || WindowManagerService.localLOGV)
&& (mShownAlpha == 1.0 || mShownAlpha == 0.0)) Slog.v(
TAG, "computeShownFrameLocked: Animating " + this + " mAlpha=" + mAlpha
+ " self=" + (selfTransformation ? mTransformation.getAlpha() : "null")
+ " attached=" + (attachedTransformation == null ?
"null" : attachedTransformation.getAlpha())
+ " app=" + (appTransformation == null ? "null" : appTransformation.getAlpha())
+ " screen=" + (screenAnimation ?
screenRotationAnimation.getEnterTransformation().getAlpha() : "null"));
return;
} else if (mIsWallpaper && mService.mWindowPlacerLocked.mWallpaperActionPending) {
return;
} else if (mWin.isDragResizeChanged()) {
// This window is awaiting a relayout because user just started (or ended)
// drag-resizing. The shown frame (which affects surface size and pos)
// should not be updated until we get next finished draw with the new surface.
// Otherwise one or two frames rendered with old settings would be displayed
// with new geometry.
return;
}
//11 后面这些针对动画完成或者不包含动画的情况
if (WindowManagerService.localLOGV) Slog.v(
TAG, "computeShownFrameLocked: " + this +
" not attached, mAlpha=" + mAlpha);
MagnificationSpec spec = null;
//TODO (multidisplay): Magnification is supported only for the default display.
if (mService.mAccessibilityController != null && displayId == DEFAULT_DISPLAY) {
spec = mService.mAccessibilityController.getMagnificationSpecForWindowLocked(mWin);
}
if (spec != null) { //12 mAccessibilityController 指定特殊变换的
final Rect frame = mWin.mFrame;
final float tmpFloats[] = mService.mTmpFloats;
final Matrix tmpMatrix = mWin.mTmpMatrix;
tmpMatrix.setScale(mWin.mGlobalScale, mWin.mGlobalScale);
tmpMatrix.postTranslate(frame.left + mWin.mXOffset, frame.top + mWin.mYOffset);
if (spec != null && !spec.isNop()) {
tmpMatrix.postScale(spec.scale, spec.scale);
tmpMatrix.postTranslate(spec.offsetX, spec.offsetY);
}
tmpMatrix.getValues(tmpFloats);
mHaveMatrix = true;
mDsDx = tmpFloats[Matrix.MSCALE_X];
mDtDx = tmpFloats[Matrix.MSKEW_Y];
mDsDy = tmpFloats[Matrix.MSKEW_X];
mDtDy = tmpFloats[Matrix.MSCALE_Y];
float x = tmpFloats[Matrix.MTRANS_X];
float y = tmpFloats[Matrix.MTRANS_Y];
mWin.mShownPosition.set(Math.round(x), Math.round(y));
mShownAlpha = mAlpha;
} else { //13 设置位置
mWin.mShownPosition.set(mWin.mFrame.left, mWin.mFrame.top);
if (mWin.mXOffset != 0 || mWin.mYOffset != 0) {
mWin.mShownPosition.offset(mWin.mXOffset, mWin.mYOffset);
}
mShownAlpha = mAlpha;
mHaveMatrix = false;
mDsDx = mWin.mGlobalScale;
mDtDx = 0;
mDsDy = 0;
mDtDy = mWin.mGlobalScale;
}
}
Matrix{[1.0, 0.0, 517.0][0.0, 1.0, 1448.0][0.0, 0.0, 1.0]}
Matrix{[0.48888886, 0.0, -269.99997][0.0, 0.48888886, 556.66675][0.0, 0.0, 1.0]}
Matrix{[0.48888886, 0.0, 247.00003][0.0, 0.48888886, 2004.6667][0.0, 0.0, 1.0]}