From 591618c8b58e2a5200dbaeda73041e842d581d2b Mon Sep 17 00:00:00 2001
From: Nataniel Borges <natanieljr@google.com>
Date: Thu, 27 Dec 2018 11:32:26 -0800
Subject: [PATCH] Display only elements actually visible on the screen as
 "Visible"

Use the visibleRegion property to determine if a layer is visible on
the screen or not. Elements may have a size and a crop but be displayed
below another.

While the visible option cannot be used to render the elements due to
transforms, it only has a value if the element is displayed on the
screen.

Note that elements may still not appear on the screen as all their
visible regions are below the screen (right < 0 or bottom < 0)

Test: Open trace in winscope, check if only layers visible on the screen have a visible chip and are displayed.
Change-Id: I75137a5057a5bda96db887b110b053e64b49f885
---
 tools/winscope/src/transform_sf.js | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/tools/winscope/src/transform_sf.js b/tools/winscope/src/transform_sf.js
index bfe12d1e6..a3693c42d 100644
--- a/tools/winscope/src/transform_sf.js
+++ b/tools/winscope/src/transform_sf.js
@@ -89,11 +89,12 @@ function transform_layer(layer, {parentBounds, parentHidden}) {
    * @param {layer} layer
    * @returns if the layer is visible on screen or not
    */
-  function is_visible(layer, visibleRect) {
+  function is_visible(layer) {
     var visible = (layer.activeBuffer || layer.type === 'ColorLayer')
-        && !hidden && layer.color.a > 0;
-    if (visibleRect != undefined) {
-      visible &= has_size(visibleRect);
+                  && !hidden && layer.color.a > 0;
+    if (visible && layer.visibleRegion != undefined) {
+      var isRectVisible = layer.visibleRegion.rect.some(has_size);
+      visible &= isRectVisible;
     }
     return visible
   }
@@ -101,7 +102,7 @@ function transform_layer(layer, {parentBounds, parentHidden}) {
   var chips = [];
   var rect = transform_bounds(layer, parentBounds);
   var hidden = (layer.flags & FLAG_HIDDEN) != 0 || parentHidden;
-  var visible = is_visible(layer, rect);
+  var visible = is_visible(layer);
   if (visible) {
     chips.push(get_visible_chip());
   } else {