[D3D12] Make tiled resource toggleable, disable debug layer by default

src/xenia/ui/d3d12/d3d12_api.cc

@@ -0,0 +1,16 @@
+/**
+ ******************************************************************************
+ * Xenia : Xbox 360 Emulator Research Project                                 *
+ ******************************************************************************
+ * Copyright 2018 Ben Vanik. All rights reserved.                             *
+ * Released under the BSD license - see LICENSE in the root for more details. *
+ ******************************************************************************
+ */
+
+#include "xenia/ui/d3d12/d3d12_api.h"
+
+DEFINE_bool(d3d12_tiled_resources, true,
+            "Enable tiled resources for shared memory emulation. Disabling "
+            "them greatly increases video memory usage - a 512 MB buffer is "
+            "created - but allows graphics debuggers that don't support tiled "
+            "resources to work.");

src/xenia/ui/d3d12/d3d12_api.h

@@ -10,6 +10,8 @@
 #ifndef XENIA_UI_D3D12_D3D12_API_H_
 #define XENIA_UI_D3D12_D3D12_API_H_
 
+#include <gflags/gflags.h>
+
 // This must be included before D3D and DXGI for things like NOMINMAX.
 #include "xenia/base/platform_win.h"
 
@@ -19,4 +21,6 @@
 
 #define XELOGD3D XELOGI
 
+DECLARE_bool(d3d12_tiled_resources);
+
 #endif  // XENIA_UI_D3D12_D3D12_API_H_

src/xenia/ui/d3d12/d3d12_provider.cc

@@ -14,7 +14,7 @@
 #include "xenia/base/logging.h"
 #include "xenia/ui/d3d12/d3d12_context.h"
 
-DEFINE_bool(d3d12_debug, true, "Enable Direct3D 12 and DXGI debug layer.");
+DEFINE_bool(d3d12_debug, false, "Enable Direct3D 12 and DXGI debug layer.");
 DEFINE_int32(d3d12_adapter_index, -1, "Index of the DXGI adapter to use. "
              "-1 for any physical adapter, -2 for WARP software rendering.");
 
@@ -155,8 +155,15 @@ bool D3D12Provider::IsDeviceSupported(ID3D12Device* device) {
                                          sizeof(options)))) {
     return false;
   }
-  // Tiled resources required for virtual memory.
-  return options.TiledResourcesTier >= D3D12_TILED_RESOURCES_TIER_1;
+
+  // Tiled resources required for shared memory emulation without excessive
+  // video memory usage.
+  if (FLAGS_d3d12_tiled_resources &&
+      options.TiledResourcesTier < D3D12_TILED_RESOURCES_TIER_1) {
+    return false;
+  }
+
+  return true;
 }
 
 std::unique_ptr<GraphicsContext> D3D12Provider::CreateContext(