commit 9d763b7014c9f16172d5a43fe8574add0daa23c0
author Lucas Dupin <dupin@google.com> Mon Apr 20 18:42:31 2020 -0700
committer Lucas Dupin <dupin@google.com> Thu Apr 23 11:26:46 2020 -0700
tree 3e86369abf0f44b51ec98fbdea2abb1dfdf31d64
parent 2af0642bfb6548cc6c4962c5e9d42d6bfbbdc907

Do not blur when doing region sampling

The luma approximation will already be pretty good without the blurs.

Test: RegionSamplingTest
Test: libsurfaceflinger_test
Fixes: 154556259
Change-Id: I4010ac54aee2e23bd8cf155f591584eeec425702

services/surfaceflinger/SurfaceFlinger.cpp

diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 352b28f..25ac802 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -5674,13 +5674,13 @@
                                              usage, "screenshot");
 
     return captureScreenCommon(renderArea, traverseLayers, *outBuffer, useIdentityTransform,
-                               outCapturedSecureLayers);
+                               false /* regionSampling */, outCapturedSecureLayers);
 }
 
 status_t SurfaceFlinger::captureScreenCommon(RenderArea& renderArea,
                                              TraverseLayersFunction traverseLayers,
                                              const sp<GraphicBuffer>& buffer,
-                                             bool useIdentityTransform,
+                                             bool useIdentityTransform, bool regionSampling,
                                              bool& outCapturedSecureLayers) {
     // This mutex protects syncFd and captureResult for communication of the return values from the
     // main thread back to this Binder thread
@@ -5711,7 +5711,7 @@
             renderArea.render([&] {
                 result = captureScreenImplLocked(renderArea, traverseLayers, buffer.get(),
                                                  useIdentityTransform, forSystem, &fd,
-                                                 outCapturedSecureLayers);
+                                                 regionSampling, outCapturedSecureLayers);
             });
         }
 
@@ -5748,7 +5748,8 @@
 void SurfaceFlinger::renderScreenImplLocked(const RenderArea& renderArea,
                                             TraverseLayersFunction traverseLayers,
                                             const sp<GraphicBuffer>& buffer,
-                                            bool useIdentityTransform, int* outSyncFd) {
+                                            bool useIdentityTransform, bool regionSampling,
+                                            int* outSyncFd) {
     ATRACE_CALL();
 
     const auto reqWidth = renderArea.getReqWidth();
@@ -5804,6 +5805,12 @@
             for (auto& settings : results) {
                 settings.geometry.positionTransform =
                         transform.asMatrix4() * settings.geometry.positionTransform;
+                // There's no need to process blurs when we're executing region sampling,
+                // we're just trying to understand what we're drawing, and doing so without
+                // blurs is already a pretty good approximation.
+                if (regionSampling) {
+                    settings.backgroundBlurRadius = 0;
+                }
             }
             clientCompositionLayers.insert(clientCompositionLayers.end(),
                                            std::make_move_iterator(results.begin()),
@@ -5841,7 +5848,8 @@
                                                  TraverseLayersFunction traverseLayers,
                                                  const sp<GraphicBuffer>& buffer,
                                                  bool useIdentityTransform, bool forSystem,
-                                                 int* outSyncFd, bool& outCapturedSecureLayers) {
+                                                 int* outSyncFd, bool regionSampling,
+                                                 bool& outCapturedSecureLayers) {
     ATRACE_CALL();
 
     traverseLayers([&](Layer* layer) {
@@ -5856,7 +5864,8 @@
         ALOGW("FB is protected: PERMISSION_DENIED");
         return PERMISSION_DENIED;
     }
-    renderScreenImplLocked(renderArea, traverseLayers, buffer, useIdentityTransform, outSyncFd);
+    renderScreenImplLocked(renderArea, traverseLayers, buffer, useIdentityTransform, regionSampling,
+                           outSyncFd);
     return NO_ERROR;
 }