diff --git a/services/surfaceflinger/Layer.cpp b/services/surfaceflinger/Layer.cpp
index 51e1f00..26a09e7 100644
--- a/services/surfaceflinger/Layer.cpp
+++ b/services/surfaceflinger/Layer.cpp
@@ -2125,11 +2125,15 @@
     auto parent = useDrawing ? mDrawingParent.promote() : mCurrentParent.promote();
     if (parent != nullptr) {
         layerInfo->set_parent(parent->sequence);
+    } else {
+        layerInfo->set_parent(-1);
     }
 
     auto zOrderRelativeOf = state.zOrderRelativeOf.promote();
     if (zOrderRelativeOf != nullptr) {
         layerInfo->set_z_order_relative_of(zOrderRelativeOf->sequence);
+    } else {
+        layerInfo->set_z_order_relative_of(-1);
     }
 
     // XXX getBE().compositionInfo.mBuffer is not protected
diff --git a/services/surfaceflinger/layerproto/LayerProtoParser.cpp b/services/surfaceflinger/layerproto/LayerProtoParser.cpp
index 5c72fea..7ab57f9 100644
--- a/services/surfaceflinger/layerproto/LayerProtoParser.cpp
+++ b/services/surfaceflinger/layerproto/LayerProtoParser.cpp
@@ -199,13 +199,13 @@
         }
     }
 
-    if (layerProto.has_parent()) {
+    if (layerProto.parent() != -1) {
         if (layerMap.count(layerProto.parent()) > 0) {
             currLayer->parent = layerMap[layerProto.parent()];
         }
     }
 
-    if (layerProto.has_z_order_relative_of()) {
+    if (layerProto.z_order_relative_of() != -1) {
         if (layerMap.count(layerProto.z_order_relative_of()) > 0) {
             currLayer->zOrderRelativeOf = layerMap[layerProto.z_order_relative_of()];
         }
diff --git a/services/surfaceflinger/layerproto/layers.proto b/services/surfaceflinger/layerproto/layers.proto
index 72cbfac..faf0c54 100644
--- a/services/surfaceflinger/layerproto/layers.proto
+++ b/services/surfaceflinger/layerproto/layers.proto
@@ -1,156 +1,156 @@
 // Definitions for SurfaceFlinger layers.
 
-syntax = "proto2";
+syntax = "proto3";
 option optimize_for = LITE_RUNTIME;
 package android.surfaceflinger;
 
 // Contains a list of all layers.
 message LayersProto {
   repeated LayerProto layers = 1;
-  optional SizeProto resolution = 2;
-  optional string color_mode = 3;
-  optional string color_transform = 4;
-  optional int32 global_transform = 5;
+  SizeProto resolution = 2;
+  string color_mode = 3;
+  string color_transform = 4;
+  int32 global_transform = 5;
 }
 
 // Information about each layer.
 message LayerProto {
   // unique id per layer.
-  optional int32 id = 1;
+  int32 id = 1;
   // unique name per layer.
-  optional string name = 2;
+  string name = 2;
   // list of children this layer may have. May be empty.
   repeated int32 children = 3;
   // list of layers that are z order relative to this layer.
   repeated int32 relatives = 4;
   // The type of layer, ex Color, Layer
-  optional string type = 5;
-  optional RegionProto transparent_region = 6;
-  optional RegionProto visible_region = 7;
-  optional RegionProto damage_region = 8;
-  optional uint32 layer_stack = 9;
+  string type = 5;
+  RegionProto transparent_region = 6;
+  RegionProto visible_region = 7;
+  RegionProto damage_region = 8;
+  uint32 layer_stack = 9;
   // The layer's z order. Can be z order in layer stack, relative to parent,
   // or relative to another layer specified in zOrderRelative.
-  optional int32 z = 10;
+  int32 z = 10;
   // The layer's position on the display.
-  optional PositionProto position = 11;
+  PositionProto position = 11;
   // The layer's requested position.
-  optional PositionProto requested_position = 12;
+  PositionProto requested_position = 12;
   // The layer's size.
-  optional SizeProto size = 13;
+  SizeProto size = 13;
   // The layer's crop in it's own bounds.
-  optional RectProto crop = 14;
+  RectProto crop = 14;
   // The layer's crop in it's parent's bounds.
-  optional RectProto final_crop = 15 [deprecated=true];
-  optional bool is_opaque = 16;
-  optional bool invalidate = 17;
-  optional string dataspace = 18;
-  optional string pixel_format = 19;
+  RectProto final_crop = 15 [deprecated=true];
+  bool is_opaque = 16;
+  bool invalidate = 17;
+  string dataspace = 18;
+  string pixel_format = 19;
   // The layer's actual color.
-  optional ColorProto color = 20;
+  ColorProto color = 20;
   // The layer's requested color.
-  optional ColorProto requested_color = 21;
+  ColorProto requested_color = 21;
   // Can be any combination of
   //    hidden = 0x01
   //    opaque = 0x02,
   //    secure = 0x80,
-  optional uint32 flags = 22;
+  uint32 flags = 22;
   // The layer's actual transform
-  optional TransformProto transform = 23;
+  TransformProto transform = 23;
   // The layer's requested transform.
-  optional TransformProto requested_transform = 24;
+  TransformProto requested_transform = 24;
   // The parent layer. This value can be null if there is no parent.
-  optional int32 parent = 25 [default = -1];
+  int32 parent = 25;
   // The layer that this layer has a z order relative to. This value can be null.
-  optional int32 z_order_relative_of = 26 [default = -1];
+  int32 z_order_relative_of = 26;
   // This value can be null if there's nothing to draw.
-  optional ActiveBufferProto active_buffer = 27;
+  ActiveBufferProto active_buffer = 27;
   // The number of frames available.
-  optional int32 queued_frames = 28;
-  optional bool refresh_pending = 29;
+  int32 queued_frames = 28;
+  bool refresh_pending = 29;
   // The layer's composer backend destination frame
-  optional RectProto hwc_frame = 30;
+  RectProto hwc_frame = 30;
   // The layer's composer backend source crop
-  optional FloatRectProto hwc_crop = 31;
+  FloatRectProto hwc_crop = 31;
   // The layer's composer backend transform
-  optional int32 hwc_transform = 32;
-  optional int32 window_type = 33 [deprecated=true];
-  optional int32 app_id = 34 [deprecated=true];
+  int32 hwc_transform = 32;
+  int32 window_type = 33 [deprecated=true];
+  int32 app_id = 34 [deprecated=true];
   // The layer's composition type
-  optional int32 hwc_composition_type = 35;
+  int32 hwc_composition_type = 35;
   // If it's a buffer layer, indicate if the content is protected
-  optional bool is_protected = 36;
+  bool is_protected = 36;
   // Current frame number being rendered.
-  optional uint64 curr_frame = 37;
+  uint64 curr_frame = 37;
   // A list of barriers that the layer is waiting to update state.
   repeated BarrierLayerProto barrier_layer = 38;
   // If active_buffer is not null, record its transform.
-  optional TransformProto buffer_transform = 39;
-  optional int32 effective_scaling_mode = 40;
+  TransformProto buffer_transform = 39;
+  int32 effective_scaling_mode = 40;
   // Layer's corner radius.
-  optional float corner_radius = 41;
+  float corner_radius = 41;
   // Metadata map. May be empty.
   map<int32, bytes> metadata = 42;
 
-  optional TransformProto effective_transform = 43;
-  optional FloatRectProto source_bounds = 44;
-  optional FloatRectProto bounds = 45;
-  optional FloatRectProto screen_bounds = 46;
+  TransformProto effective_transform = 43;
+  FloatRectProto source_bounds = 44;
+  FloatRectProto bounds = 45;
+  FloatRectProto screen_bounds = 46;
 }
 
 message PositionProto {
-  optional float x = 1;
-  optional float y = 2;
+  float x = 1;
+  float y = 2;
 }
 
 message SizeProto {
-  optional int32 w = 1;
-  optional int32 h = 2;
+  int32 w = 1;
+  int32 h = 2;
 }
 
 message TransformProto {
-  optional float dsdx = 1;
-  optional float dtdx = 2;
-  optional float dsdy = 3;
-  optional float dtdy = 4;
+  float dsdx = 1;
+  float dtdx = 2;
+  float dsdy = 3;
+  float dtdy = 4;
 }
 
 message RegionProto {
-  optional uint64 id = 1;
+  uint64 id = 1;
   repeated RectProto rect = 2;
 }
 
 message RectProto {
-  optional int32 left   = 1;
-  optional int32 top    = 2;
-  optional int32 right  = 3;
-  optional int32 bottom = 4;
+  int32 left   = 1;
+  int32 top    = 2;
+  int32 right  = 3;
+  int32 bottom = 4;
 }
 
 message FloatRectProto {
-  optional float left = 1;
-  optional float top = 2;
-  optional float right = 3;
-  optional float bottom = 4;
+  float left = 1;
+  float top = 2;
+  float right = 3;
+  float bottom = 4;
 }
 
 message ActiveBufferProto {
-  optional uint32 width = 1;
-  optional uint32 height = 2;
-  optional uint32 stride = 3;
-  optional int32 format = 4;
+  uint32 width = 1;
+  uint32 height = 2;
+  uint32 stride = 3;
+  int32 format = 4;
 }
 
 message ColorProto {
-  optional float r = 1;
-  optional float g = 2;
-  optional float b = 3;
-  optional float a = 4;
+  float r = 1;
+  float g = 2;
+  float b = 3;
+  float a = 4;
 }
 
 message BarrierLayerProto {
   // layer id the barrier is waiting on.
-  optional int32 id = 1;
+  int32 id = 1;
   // frame number the barrier is waiting on.
-  optional uint64 frame_number = 2;
+  uint64 frame_number = 2;
 }