commit aa48888ad42b82945f0df5ca096cef9c973f054f
author Dileep Kumar Reddi <dkumarre@codeaurora.org> Tue Dec 16 11:19:45 2014 +0530
committer radhakrishna <radhakrishna@codeaurora.org> Mon Feb 02 15:57:16 2015 +0530
tree 3d22f0b0d401faa808622dd6e3f041df11a6ddcd
parent f4e2e0c579b68d0f3ef2476709d08dd526dbbfa1

hwc: Use displayFrame information in caching

In some use-cases layer handle is not changing but
displayFrame is changing, resulting flickers.

Change-Id: I4e5a2756efe76754ab517f65dae75fc07db48435

libhwcomposer/hwc_copybit.cpp

diff --git a/libhwcomposer/hwc_copybit.cpp b/libhwcomposer/hwc_copybit.cpp
index ca631b2..364b15c 100644
--- a/libhwcomposer/hwc_copybit.cpp
+++ b/libhwcomposer/hwc_copybit.cpp
@@ -131,6 +131,21 @@
     return renderArea;
 }
 
+bool CopyBit::isLayerChanging(hwc_display_contents_1_t *list, int k) {
+    if((mLayerCache.hnd[k] != list->hwLayers[k].handle) ||
+            (mLayerCache.displayFrame[k].left !=
+                         list->hwLayers[k].displayFrame.left) ||
+            (mLayerCache.displayFrame[k].top !=
+                         list->hwLayers[k].displayFrame.top) ||
+            (mLayerCache.displayFrame[k].right !=
+                         list->hwLayers[k].displayFrame.right) ||
+            (mLayerCache.displayFrame[k].bottom !=
+                         list->hwLayers[k].displayFrame.bottom)) {
+        return 1;
+    }
+    return 0;
+}
+
 int CopyBit::getLayersChanging(hwc_context_t *ctx,
                       hwc_display_contents_1_t *list,
                       int dpy){
@@ -146,7 +161,7 @@
     int updatingLayerCount = 0;
     for (int k = ctx->listStats[dpy].numAppLayers-1; k >= 0 ; k--){
        //swap rect will kick in only for single updating layer
-       if(mLayerCache.hnd[k] != list->hwLayers[k].handle){
+       if(isLayerChanging(list, k)) {
            updatingLayerCount ++;
            if(updatingLayerCount == 1)
              changingLayerIndex = k;
@@ -1204,6 +1219,7 @@
    layerCount = ctx->listStats[dpy].numAppLayers;
    for (int i=0; i<ctx->listStats[dpy].numAppLayers; i++){
       hnd[i] = list->hwLayers[i].handle;
+      displayFrame[i] = list->hwLayers[i].displayFrame;
    }
 }
 

libhwcomposer/hwc_copybit.h

diff --git a/libhwcomposer/hwc_copybit.h b/libhwcomposer/hwc_copybit.h
index a7ce43e..9793b4a 100644
--- a/libhwcomposer/hwc_copybit.h
+++ b/libhwcomposer/hwc_copybit.h
@@ -60,6 +60,7 @@
     struct LayerCache {
       int layerCount;
       buffer_handle_t hnd[MAX_NUM_APP_LAYERS];
+      hwc_rect_t displayFrame[MAX_NUM_APP_LAYERS];
       /* c'tor */
       LayerCache();
       /* clear caching info*/
@@ -133,6 +134,7 @@
                   int dpy);
     int checkDirtyRect(hwc_context_t *ctx, hwc_display_contents_1_t *list,
                   int dpy);
+    bool isLayerChanging(hwc_display_contents_1_t *list, int k);
 };
 
 }; //namespace qhwc