ANGLE: Allow Windows Phone to communicate swap region

eglPostSubBufferNV is used to communicate the size of the window, as
otherwise there is no way for the renderer to know if the last frame was
rendered in landscape or portrait, causing rendering glitches when the
orientation changes. The rotation flags are utilized in a few additional
places now to fix some corner cases where the rotation was not applied.

This patch should be squashed into "ANGLE-Improve-Windows-Phone-Support"
during the next ANGLE rebase.

Task-number: QTBUG-44333
Task-number: QTBUG-43502
Change-Id: Iec37f7531854184819c30c87eab82d96d56ff133
Reviewed-by: Oliver Wolff <oliver.wolff@theqtcompany.com>

1 files changed, 145 insertions, 0 deletions

diff --git a/src/angle/patches/0006-ANGLE-Allow-Windows-Phone-to-communicate-swap-region.patch b/src/angle/patches/0006-ANGLE-Allow-Windows-Phone-to-communicate-swap-region.patch
new file mode 100644
index 0000000000..5c6ef7b036
--- /dev/null
+++ b/src/angle/patches/0006-ANGLE-Allow-Windows-Phone-to-communicate-swap-region.patch
@@ -0,0 +1,145 @@
+From f0fb8d75bd2c7a894df1cb7e7d3dcd1ad0fd88d0 Mon Sep 17 00:00:00 2001
+From: Andrew Knight <andrew.knight@intopalo.com>
+Date: Sun, 3 May 2015 20:55:04 +0300
+Subject: [PATCH] ANGLE: Allow Windows Phone to communicate swap region
+
+eglPostSubBufferNV is used to communicate the size of the window, as
+otherwise there is no way for the renderer to know if the last frame was
+rendered in landscape or portrait, causing rendering glitches when the
+orientation changes. The rotation flags are utilized in a few additional
+places now to fix some corner cases where the rotation was not applied.
+
+This patch should be squashed into "ANGLE-Improve-Windows-Phone-Support"
+during the next ANGLE rebase.
+
+Task-number: QTBUG-44333
+Task-number: QTBUG-43502
+Change-Id: Iec37f7531854184819c30c87eab82d96d56ff133
+---
+ .../angle/src/libANGLE/renderer/d3d/SurfaceD3D.cpp |  2 ++
+ .../libANGLE/renderer/d3d/d3d11/SwapChain11.cpp    | 28 +++++++++++++---------
+ .../d3d/d3d11/winrt/CoreWindowNativeWindow.cpp     |  5 ++--
+ .../angle/src/libGLESv2/entry_points_egl_ext.cpp   |  2 ++
+ 4 files changed, 24 insertions(+), 13 deletions(-)
+
+diff --git a/src/3rdparty/angle/src/libANGLE/renderer/d3d/SurfaceD3D.cpp b/src/3rdparty/angle/src/libANGLE/renderer/d3d/SurfaceD3D.cpp
+index 4fde295..4a87488 100644
+--- a/src/3rdparty/angle/src/libANGLE/renderer/d3d/SurfaceD3D.cpp
++++ b/src/3rdparty/angle/src/libANGLE/renderer/d3d/SurfaceD3D.cpp
+@@ -189,6 +189,7 @@ egl::Error SurfaceD3D::swapRect(EGLint x, EGLint y, EGLint width, EGLint height)
+         return egl::Error(EGL_SUCCESS);
+     }
+ 
++#if !defined(ANGLE_ENABLE_WINDOWS_STORE) || (defined(ANGLE_ENABLE_WINDOWS_STORE) && WINAPI_FAMILY == WINAPI_FAMILY_PC_APP) // Qt WP: eglPostSubBufferNV comes here
+     if (x + width > mWidth)
+     {
+         width = mWidth - x;
+@@ -198,6 +199,7 @@ egl::Error SurfaceD3D::swapRect(EGLint x, EGLint y, EGLint width, EGLint height)
+     {
+         height = mHeight - y;
+     }
++#endif
+ 
+     if (width == 0 || height == 0)
+     {
+diff --git a/src/3rdparty/angle/src/libANGLE/renderer/d3d/d3d11/SwapChain11.cpp b/src/3rdparty/angle/src/libANGLE/renderer/d3d/d3d11/SwapChain11.cpp
+index 298f3cc..dc539cf 100644
+--- a/src/3rdparty/angle/src/libANGLE/renderer/d3d/d3d11/SwapChain11.cpp
++++ b/src/3rdparty/angle/src/libANGLE/renderer/d3d/d3d11/SwapChain11.cpp
+@@ -552,18 +552,18 @@ EGLint SwapChain11::swapRect(EGLint x, EGLint y, EGLint width, EGLint height)
+ 
+     d3d11::PositionTexCoordVertex *vertices = static_cast<d3d11::PositionTexCoordVertex*>(mappedResource.pData);
+ 
++#if defined(ANGLE_ENABLE_WINDOWS_STORE) && (WINAPI_FAMILY == WINAPI_FAMILY_PHONE_APP)
+     // Create a quad in homogeneous coordinates
+-    float x1 = (x / float(mWidth)) * 2.0f - 1.0f;
+-    float y1 = (y / float(mHeight)) * 2.0f - 1.0f;
+-    float x2 = ((x + width) / float(mWidth)) * 2.0f - 1.0f;
+-    float y2 = ((y + height) / float(mHeight)) * 2.0f - 1.0f;
++    float x1 = -1.0f;
++    float y1 = -1.0f;
++    float x2 = 1.0f;
++    float y2 = 1.0f;
+ 
+-#if defined(ANGLE_ENABLE_WINDOWS_STORE) && (WINAPI_FAMILY == WINAPI_FAMILY_PHONE_APP)
+     const float dim = std::max(mWidth, mHeight);
+-    float u1 = x / dim;
+-    float v1 = y / dim;
+-    float u2 = (x + width) / dim;
+-    float v2 = (y + height) / dim;
++    float u1 = 0;
++    float v1 = 0;
++    float u2 = float(width) / dim;
++    float v2 = float(height) / dim;
+ 
+     const NativeWindow::RotationFlags flags = mNativeWindow.rotationFlags();
+     const bool rotateL = flags == NativeWindow::RotateLeft;
+@@ -573,6 +573,12 @@ EGLint SwapChain11::swapRect(EGLint x, EGLint y, EGLint width, EGLint height)
+     d3d11::SetPositionTexCoordVertex(&vertices[2], x2, y1, rotateR ? u1 : u2, rotateL ? v2 : v1);
+     d3d11::SetPositionTexCoordVertex(&vertices[3], x2, y2, rotateL ? u1 : u2, rotateR ? v1 : v2);
+ #else
++    // Create a quad in homogeneous coordinates
++    float x1 = (x / float(mWidth)) * 2.0f - 1.0f;
++    float y1 = (y / float(mHeight)) * 2.0f - 1.0f;
++    float x2 = ((x + width) / float(mWidth)) * 2.0f - 1.0f;
++    float y2 = ((y + height) / float(mHeight)) * 2.0f - 1.0f;
++
+     float u1 = x / float(mWidth);
+     float v1 = y / float(mHeight);
+     float u2 = (x + width) / float(mWidth);
+@@ -613,8 +619,8 @@ EGLint SwapChain11::swapRect(EGLint x, EGLint y, EGLint width, EGLint height)
+     viewport.TopLeftX = 0;
+     viewport.TopLeftY = 0;
+ #if defined(ANGLE_ENABLE_WINDOWS_STORE) && (WINAPI_FAMILY == WINAPI_FAMILY_PHONE_APP)
+-    viewport.Width = (rotateL || rotateR) ? mHeight : mWidth;
+-    viewport.Height = (rotateL || rotateR) ? mWidth : mHeight;
++    viewport.Width = (rotateL || rotateR) ? height : width;
++    viewport.Height = (rotateL || rotateR) ? width : height;
+ #else
+     viewport.Width = mWidth;
+     viewport.Height = mHeight;
+diff --git a/src/3rdparty/angle/src/libANGLE/renderer/d3d/d3d11/winrt/CoreWindowNativeWindow.cpp b/src/3rdparty/angle/src/libANGLE/renderer/d3d/d3d11/winrt/CoreWindowNativeWindow.cpp
+index 350526c..fa9a69c 100644
+--- a/src/3rdparty/angle/src/libANGLE/renderer/d3d/d3d11/winrt/CoreWindowNativeWindow.cpp
++++ b/src/3rdparty/angle/src/libANGLE/renderer/d3d/d3d11/winrt/CoreWindowNativeWindow.cpp
+@@ -100,6 +100,7 @@ bool CoreWindowNativeWindow::registerForSizeChangeEvents()
+     if (SUCCEEDED(result))
+     {
+         result = mDisplayInformation->add_OrientationChanged(orientationChangedHandler.Get(), &mOrientationChangedEventToken);
++        orientationChangedHandler->Invoke(mDisplayInformation.Get(), nullptr);
+     }
+ #endif
+ 
+@@ -135,8 +136,8 @@ HRESULT CoreWindowNativeWindow::createSwapChain(ID3D11Device *device, DXGIFactor
+     }
+ 
+     DXGI_SWAP_CHAIN_DESC1 swapChainDesc = { 0 };
+-    swapChainDesc.Width = width;
+-    swapChainDesc.Height = height;
++    swapChainDesc.Width = mRotationFlags ? height : width;
++    swapChainDesc.Height = mRotationFlags ? width : height;
+     swapChainDesc.Format = format;
+     swapChainDesc.Stereo = FALSE;
+     swapChainDesc.SampleDesc.Count = 1;
+diff --git a/src/3rdparty/angle/src/libGLESv2/entry_points_egl_ext.cpp b/src/3rdparty/angle/src/libGLESv2/entry_points_egl_ext.cpp
+index ded73db..62f3ca1 100644
+--- a/src/3rdparty/angle/src/libGLESv2/entry_points_egl_ext.cpp
++++ b/src/3rdparty/angle/src/libGLESv2/entry_points_egl_ext.cpp
+@@ -101,12 +101,14 @@ EGLBoolean EGLAPIENTRY PostSubBufferNV(EGLDisplay dpy, EGLSurface surface, EGLin
+         return EGL_FALSE;
+     }
+ 
++#if !defined(ANGLE_ENABLE_WINDOWS_STORE) || (defined(ANGLE_ENABLE_WINDOWS_STORE) && WINAPI_FAMILY == WINAPI_FAMILY_PC_APP) // Qt WP: Allow this entry point as a workaround
+     if (!display->getExtensions().postSubBuffer)
+     {
+         // Spec is not clear about how this should be handled.
+         SetGlobalError(Error(EGL_SUCCESS));
+         return EGL_TRUE;
+     }
++#endif
+ 
+     error = eglSurface->postSubBuffer(x, y, width, height);
+     if (error.isError())
+-- 
+1.9.5.msysgit.0
+