Add support for resizing the window without recreating the swap chain in D3D11.

src/libEGL/Surface.cpp

@@ -153,6 +153,29 @@ bool Surface::resetSwapChain()
     return true;
 }
 
+bool Surface::resizeSwapChain(int backbufferWidth, int backbufferHeight)
+{
+    ASSERT(backbufferWidth >= 0 && backbufferHeight >= 0);
+    ASSERT(mSwapChain);
+
+    EGLint status = mSwapChain->resize(backbufferWidth, backbufferHeight);
+
+    if (status == EGL_CONTEXT_LOST)
+    {
+        mDisplay->notifyDeviceLost();
+        return false;
+    }
+    else if (status != EGL_SUCCESS)
+    {
+        return error(status, false);
+    }
+
+    mWidth = backbufferWidth;
+    mHeight = backbufferHeight;
+
+    return true;
+}
+
 bool Surface::resetSwapChain(int backbufferWidth, int backbufferHeight)
 {
     ASSERT(backbufferWidth >= 0 && backbufferHeight >= 0);
@@ -306,9 +329,17 @@ bool Surface::checkForOutOfDateSwapChain()
     int clientHeight = client.bottom - client.top;
     bool sizeDirty = clientWidth != getWidth() || clientHeight != getHeight();
 
-    if (sizeDirty || mSwapIntervalDirty)
+    if (mSwapIntervalDirty)
     {
         resetSwapChain(clientWidth, clientHeight);
+    }
+    else if (sizeDirty)
+    {
+        resizeSwapChain(clientWidth, clientHeight);
+    }
+
+    if (mSwapIntervalDirty || sizeDirty)
+    {
         if (static_cast<egl::Surface*>(getCurrentDrawSurface()) == this)
         {
             glMakeCurrent(glGetCurrentContext(), static_cast<egl::Display*>(getCurrentDisplay()), this);
@@ -316,6 +347,7 @@ bool Surface::checkForOutOfDateSwapChain()
 
         return true;
     }
+
     return false;
 }
 

src/libEGL/Surface.h

@@ -75,6 +75,7 @@ private:
 
     void subclassWindow();
     void unsubclassWindow();
+    bool resizeSwapChain(int backbufferWidth, int backbufferHeight);
     bool resetSwapChain(int backbufferWidth, int backbufferHeight);
     bool swapRect(EGLint x, EGLint y, EGLint width, EGLint height);
 

src/libGLESv2/renderer/SwapChain.h

@@ -31,6 +31,7 @@ class SwapChain
 
     virtual ~SwapChain() {};
 
+    virtual EGLint resize(EGLint backbufferWidth, EGLint backbufferSize) = 0;
     virtual EGLint reset(EGLint backbufferWidth, EGLint backbufferHeight, EGLint swapInterval) = 0;
     virtual EGLint swapRect(EGLint x, EGLint y, EGLint width, EGLint height) = 0;
 

src/libGLESv2/renderer/SwapChain11.cpp

@@ -363,6 +363,66 @@ EGLint SwapChain11::resetOffscreenTexture(int backbufferWidth, int backbufferHei
     return EGL_SUCCESS;
 }
 
+EGLint SwapChain11::resize(EGLint backbufferWidth, EGLint backbufferHeight)
+{
+    ID3D11Device *device = mRenderer->getDevice();
+
+    if (device == NULL)
+    {
+        return EGL_BAD_ACCESS;
+    }
+
+    // Can only call resize if we have already created our swap buffer and resources
+    ASSERT(mSwapChain && mBackBufferTexture && mBackBufferRTView);
+
+    if (mBackBufferTexture)
+    {
+        mBackBufferTexture->Release();
+        mBackBufferTexture = NULL;
+    }
+
+    if (mBackBufferRTView)
+    {
+        mBackBufferRTView->Release();
+        mBackBufferRTView = NULL;
+    }
+
+    // Resize swap chain
+    DXGI_FORMAT backbufferDXGIFormat = gl_d3d11::ConvertRenderbufferFormat(mBackBufferFormat);
+    HRESULT result = mSwapChain->ResizeBuffers(2, backbufferWidth, backbufferHeight, backbufferDXGIFormat, 0);
+
+    if (FAILED(result))
+    {
+        ERR("Error resizing swap chain buffers: 0x%08X", result);
+        release();
+
+        if (d3d11::isDeviceLostError(result))
+        {
+            return EGL_CONTEXT_LOST;
+        }
+        else
+        {
+            return EGL_BAD_ALLOC;
+        }
+    }
+
+    result = mSwapChain->GetBuffer(0, __uuidof(ID3D11Texture2D), (LPVOID*)&mBackBufferTexture);
+    ASSERT(SUCCEEDED(result));
+    if (SUCCEEDED(result))
+    {
+        d3d11::SetDebugName(mBackBufferTexture, "Back buffer texture");
+    }
+
+    result = device->CreateRenderTargetView(mBackBufferTexture, NULL, &mBackBufferRTView);
+    ASSERT(SUCCEEDED(result));
+    if (SUCCEEDED(result))
+    {
+        d3d11::SetDebugName(mBackBufferRTView, "Back buffer render target");
+    }
+
+    return resetOffscreenTexture(backbufferWidth, backbufferHeight);
+}
+
 EGLint SwapChain11::reset(int backbufferWidth, int backbufferHeight, EGLint swapInterval)
 {
     ID3D11Device *device = mRenderer->getDevice();

src/libGLESv2/renderer/SwapChain11.h

@@ -25,6 +25,7 @@ class SwapChain11 : public SwapChain
                 GLenum backBufferFormat, GLenum depthBufferFormat);
     virtual ~SwapChain11();
 
+    EGLint resize(EGLint backbufferWidth, EGLint backbufferHeight);
     virtual EGLint reset(EGLint backbufferWidth, EGLint backbufferHeight, EGLint swapInterval);
     virtual EGLint swapRect(EGLint x, EGLint y, EGLint width, EGLint height);
 

src/libGLESv2/renderer/SwapChain9.cpp

@@ -30,6 +30,7 @@ SwapChain9::SwapChain9(Renderer9 *renderer, HWND window, HANDLE shareHandle,
     mOffscreenTexture = NULL;
     mWidth = -1;
     mHeight = -1;
+    mSwapInterval = -1;
 }
 
 SwapChain9::~SwapChain9()
@@ -88,6 +89,12 @@ static DWORD convertInterval(EGLint interval)
     return D3DPRESENT_INTERVAL_DEFAULT;
 }
 
+EGLint SwapChain9::resize(int backbufferWidth, int backbufferHeight)
+{
+    // D3D9 does not support resizing swap chains without recreating them
+    return reset(backbufferWidth, backbufferHeight, mSwapInterval);
+}
+
 EGLint SwapChain9::reset(int backbufferWidth, int backbufferHeight, EGLint swapInterval)
 {
     IDirect3DDevice9 *device = mRenderer->getDevice();
@@ -264,6 +271,7 @@ EGLint SwapChain9::reset(int backbufferWidth, int backbufferHeight, EGLint swapI
 
     mWidth = backbufferWidth;
     mHeight = backbufferHeight;
+    mSwapInterval = swapInterval;
 
     return EGL_SUCCESS;
 }

src/libGLESv2/renderer/SwapChain9.h

@@ -25,6 +25,7 @@ class SwapChain9 : public SwapChain
                GLenum backBufferFormat, GLenum depthBufferFormat);
     virtual ~SwapChain9();
 
+    EGLint resize(EGLint backbufferWidth, EGLint backbufferHeight);
     virtual EGLint reset(EGLint backbufferWidth, EGLint backbufferHeight, EGLint swapInterval);
     virtual EGLint swapRect(EGLint x, EGLint y, EGLint width, EGLint height);
 
@@ -42,6 +43,7 @@ class SwapChain9 : public SwapChain
     Renderer9 *mRenderer;
     EGLint mHeight;
     EGLint mWidth;
+    EGLint mSwapInterval;
 
     IDirect3DSwapChain9 *mSwapChain;
     IDirect3DSurface9 *mBackBuffer;