Minimizes changes of the depth stencil buffer

src/libGLESv2/Context.cpp

@@ -285,6 +285,7 @@ void Context::makeCurrent(egl::Display *display, egl::Surface *surface)
 void Context::markAllStateDirty()
 {
     mAppliedRenderTargetSerial = 0;
+    mAppliedDepthbufferSerial = 0;
     mAppliedProgram = 0;
 
     mClearStateDirty = true;
@@ -1642,7 +1643,12 @@ bool Context::applyRenderTarget(bool ignoreViewport)
         mAppliedRenderTargetSerial = renderTargetSerial;
     }
 
-    device->SetDepthStencilSurface(depthStencil);
+    unsigned int depthbufferSerial = framebufferObject->getDepthbufferSerial();
+    if (depthbufferSerial != mAppliedDepthbufferSerial)
+    {
+        device->SetDepthStencilSurface(depthStencil);
+        mAppliedDepthbufferSerial = depthbufferSerial;
+    }
 
     D3DVIEWPORT9 viewport;
     D3DSURFACE_DESC desc;

src/libGLESv2/Context.h

@@ -446,6 +446,7 @@ class Context
 
     unsigned int mAppliedProgram;
     unsigned int mAppliedRenderTargetSerial;
+    unsigned int mAppliedDepthbufferSerial;
 
     const char *mPsProfile;
     const char *mVsProfile;

src/libGLESv2/Framebuffer.cpp

@@ -116,6 +116,19 @@ IDirect3DSurface9 *Framebuffer::getRenderTarget()
     return NULL;
 }
 
+unsigned int Framebuffer::getDepthbufferSerial()
+{
+    gl::Context *context = gl::getContext();
+    Depthbuffer *depthbuffer = context->getDepthbuffer(mDepthbufferHandle);
+
+    if (depthbuffer)
+    {
+        return depthbuffer->getSerial();
+    }
+
+    return 0;
+}
+
 IDirect3DSurface9 *Framebuffer::getDepthStencil()
 {
     gl::Context *context = gl::getContext();

src/libGLESv2/Framebuffer.h

@@ -40,6 +40,7 @@ class Framebuffer
     IDirect3DSurface9 *getDepthStencil();
 
     unsigned int getRenderTargetSerial();
+    unsigned int getDepthbufferSerial();
 
     Colorbuffer *getColorbuffer();
     Depthbuffer *getDepthbuffer();