+ mFullSwapNextFrame = false;
+
+#ifndef DALI_PROFILE_UBUNTU
+ if( mSwapBufferCountAfterResume < THRESHOLD_SWAPBUFFER_COUNT )
+ {
+ DALI_LOG_RELEASE_INFO( "EglImplementation::SwapBuffers finished.\n" );
+ mSwapBufferCountAfterResume++;
+ }
+#endif //DALI_PROFILE_UBUNTU
+ }
+}
+
+EGLint EglImplementation::GetBufferAge(EGLSurface& eglSurface) const
+{
+ EGLint age = 0;
+ eglQuerySurface(mEglDisplay, eglSurface, EGL_BUFFER_AGE_EXT, &age);
+ if (age < 0)
+ {
+ DALI_LOG_ERROR("eglQuerySurface(%d)\n", eglGetError());
+ age = 0;
+ }
+
+ // 0 - invalid buffer
+ // 1, 2, 3
+ if (age > 3)
+ {
+ DALI_LOG_ERROR("EglImplementation::GetBufferAge() buffer age %d > 3\n", age);
+ age = 0; // shoudn't be more than 3 back buffers, if there is just reset, I don't want to add extra history level
+ }
+
+ return age;
+}
+
+void EglImplementation::SetFullSwapNextFrame()
+{
+ mFullSwapNextFrame = true;
+}
+
+void mergeRects(Rect<int>& mergingRect, const std::vector<Rect<int>>& rects)
+{
+ uint32_t i = 0;
+ if (mergingRect.IsEmpty())
+ {
+ for (;i < rects.size(); i++)
+ {
+ if (!rects[i].IsEmpty())
+ {
+ mergingRect = rects[i];
+ break;
+ }
+ }
+ }
+
+ for (;i < rects.size(); i++)
+ {
+ mergingRect.Merge(rects[i]);
+ }
+}
+
+void insertRects(std::list<std::vector<Rect<int>>>& damagedRectsList, const std::vector<Rect<int>>& damagedRects)
+{
+ damagedRectsList.push_front(damagedRects);
+ if (damagedRectsList.size() > 4) // past triple buffers + current
+ {
+ damagedRectsList.pop_back();
+ }
+}
+
+void EglImplementation::SetDamage( EGLSurface& eglSurface, const std::vector<Rect<int>>& damagedRects, Rect<int>& clippingRect )
+{
+ if (!mPartialUpdateRequired)
+ {
+ return;
+ }
+
+ if (eglSurface != EGL_NO_SURFACE) // skip if using surfaceless context
+ {
+ EGLint width = 0;
+ EGLint height = 0;
+ eglQuerySurface(mEglDisplay, eglSurface, EGL_WIDTH, &width);
+ eglQuerySurface(mEglDisplay, eglSurface, EGL_HEIGHT, &height);
+ Rect<int> surfaceRect(0, 0, width, height);
+
+ mSurfaceRect = surfaceRect;
+
+ if (mFullSwapNextFrame)
+ {
+ insertRects(mBufferDamagedRects, std::vector<Rect<int>>(1, surfaceRect));
+ clippingRect = Rect<int>();
+ return;
+ }
+
+ EGLint bufferAge = GetBufferAge(eglSurface);
+
+ // Buffer age 0 means the back buffer in invalid and requires full swap
+ if (!damagedRects.size() || bufferAge == 0)
+ {
+ // No damage or buffer is out of order or buffer age is reset
+ insertRects(mBufferDamagedRects, std::vector<Rect<int>>(1, surfaceRect));
+ clippingRect = Rect<int>();
+ return;
+ }
+
+ // We push current frame damaged rects here, zero index for current frame
+ insertRects(mBufferDamagedRects, damagedRects);
+
+ // Merge damaged rects into clipping rect
+ auto bufferDamagedRects = mBufferDamagedRects.begin();
+ while (bufferAge-- >= 0 && bufferDamagedRects != mBufferDamagedRects.end())
+ {
+ const std::vector<Rect<int>>& rects = *bufferDamagedRects++;
+ mergeRects(clippingRect, rects);
+ }
+
+ if (!clippingRect.Intersect(surfaceRect) || clippingRect.Area() > surfaceRect.Area() * 0.8)
+ {
+ // clipping area too big or doesn't intersect surface rect
+ clippingRect = Rect<int>();
+ return;
+ }
+
+ // DALI_LOG_ERROR("eglSetDamageRegionKHR(%d, %d, %d, %d)\n", clippingRect.x, clippingRect.y, clippingRect.width, clippingRect.height);
+ EGLBoolean result = mEglSetDamageRegionKHR(mEglDisplay, eglSurface, reinterpret_cast<int*>(&clippingRect), 1);
+ if (result == EGL_FALSE)
+ {
+ DALI_LOG_ERROR("eglSetDamageRegionKHR(%d)\n", eglGetError());
+ }
+ }
+}
+
+void EglImplementation::SwapBuffers(EGLSurface& eglSurface, const std::vector<Rect<int>>& damagedRects)
+{
+ if (eglSurface != EGL_NO_SURFACE ) // skip if using surfaceless context
+ {
+ if (!mPartialUpdateRequired || mFullSwapNextFrame || !damagedRects.size() || (damagedRects[0].Area() > mSurfaceRect.Area() * 0.8) )
+ {
+ SwapBuffers(eglSurface);
+ return;
+ }
+
+#ifndef DALI_PROFILE_UBUNTU
+ if( mSwapBufferCountAfterResume < THRESHOLD_SWAPBUFFER_COUNT )
+ {
+ DALI_LOG_RELEASE_INFO( "EglImplementation::SwapBuffers started.\n" );
+ }
+#endif //DALI_PROFILE_UBUNTU
+
+ std::vector< Rect< int > > mergedRects = damagedRects;
+
+ // Merge intersecting rects, form an array of non intersecting rects to help driver a bit
+ // Could be optional and can be removed, needs to be checked with and without on platform
+ const int n = mergedRects.size();
+ for(int i = 0; i < n-1; i++)
+ {
+ if (mergedRects[i].IsEmpty())
+ {
+ continue;
+ }
+
+ for (int j = i+1; j < n; j++)
+ {
+ if (mergedRects[j].IsEmpty())
+ {
+ continue;
+ }
+
+ if (mergedRects[i].Intersects(mergedRects[j]))
+ {
+ mergedRects[i].Merge(mergedRects[j]);
+ mergedRects[j].width = 0;
+ mergedRects[j].height = 0;
+ }
+ }
+ }
+
+ int j = 0;
+ for (int i = 0; i < n; i++)
+ {
+ if (!mergedRects[i].IsEmpty())
+ {
+ mergedRects[j++] = mergedRects[i];
+ }
+ }
+
+ if (j != 0)
+ {
+ mergedRects.resize(j);
+ }
+
+ if (!mergedRects.size() || (mergedRects[0].Area() > mSurfaceRect.Area() * 0.8))
+ {
+ SwapBuffers(eglSurface);
+ return;
+ }
+
+ EGLBoolean result = mEglSwapBuffersWithDamageKHR(mEglDisplay, eglSurface, reinterpret_cast<int*>(mergedRects.data()), mergedRects.size());
+ if (result == EGL_FALSE)
+ {
+ DALI_LOG_ERROR("eglSwapBuffersWithDamageKHR(%d)\n", eglGetError());
+ }