+Size Controller::Relayouter::CalculateLayoutSizeOnRequiredControllerSize(Controller& controller, const Size& requestedControllerSize, const OperationsMask& requestedOperationsMask)
+{
+ DALI_LOG_INFO(gLogFilter, Debug::Verbose, "-->CalculateLayoutSizeOnRequiredControllerSize\n");
+ Size calculatedLayoutSize;
+
+ Controller::Impl& impl = *controller.mImpl;
+ ModelPtr& model = impl.mModel;
+ VisualModelPtr& visualModel = model->mVisualModel;
+
+ // Operations that can be done only once until the text changes.
+ const OperationsMask onlyOnceOperations = static_cast<OperationsMask>(CONVERT_TO_UTF32 |
+ GET_SCRIPTS |
+ VALIDATE_FONTS |
+ GET_LINE_BREAKS |
+ BIDI_INFO |
+ SHAPE_TEXT |
+ GET_GLYPH_METRICS);
+
+ // Set the update info to relayout the whole text.
+ TextUpdateInfo& textUpdateInfo = impl.mTextUpdateInfo;
+ if((0 == textUpdateInfo.mNumberOfCharactersToAdd) &&
+ (0 == textUpdateInfo.mPreviousNumberOfCharacters) &&
+ ((visualModel->mControlSize.width < Math::MACHINE_EPSILON_1000) || (visualModel->mControlSize.height < Math::MACHINE_EPSILON_1000)))
+ {
+ textUpdateInfo.mNumberOfCharactersToAdd = model->mLogicalModel->mText.Count();
+ }
+ textUpdateInfo.mParagraphCharacterIndex = 0u;
+ textUpdateInfo.mRequestedNumberOfCharacters = model->mLogicalModel->mText.Count();
+
+ // This is to keep Index to the first character to be updated.
+ // Then restore it after calling Clear method.
+ auto updateInfoCharIndexBackup = textUpdateInfo.mCharacterIndex;
+
+ // Get a reference to the pending operations member
+ OperationsMask& operationsPending = impl.mOperationsPending;
+
+ // Layout the text for the new width.
+ // Apply the pending operations, requested operations and the only once operations.
+ // Then remove onlyOnceOperations
+ operationsPending = static_cast<OperationsMask>(operationsPending | requestedOperationsMask | onlyOnceOperations);
+
+ // Make sure the model is up-to-date before layouting
+ impl.UpdateModel(static_cast<OperationsMask>(operationsPending & ~UPDATE_LAYOUT_SIZE));
+
+ // Store the actual control's size to restore later.
+ const Size actualControlSize = visualModel->mControlSize;
+
+ DoRelayout(impl,
+ requestedControllerSize,
+ static_cast<OperationsMask>(operationsPending & ~UPDATE_LAYOUT_SIZE),
+ calculatedLayoutSize);
+
+ // Clear the update info. This info will be set the next time the text is updated.
+ textUpdateInfo.Clear();
+
+ //TODO: Refactor "DoRelayout" and extract common code of size calculation without modifying attributes of mVisualModel,
+ //TODO: then calculate GlyphPositions. Lines, Size, Layout for Natural-Size
+ //TODO: and utilize the values in OperationsPending and TextUpdateInfo without changing the original one.
+ //TODO: Also it will improve performance because there is no need todo FullRelyout on the next need for layouting.
+
+ // FullRelayoutNeeded should be true because DoRelayout is MAX_FLOAT, MAX_FLOAT.
+ // By this no need to take backup and restore it.
+ textUpdateInfo.mFullRelayoutNeeded = true;
+
+ // Restore mCharacterIndex. Because "Clear" set it to the maximum integer.
+ // The "CalculateTextUpdateIndices" does not work proprely because the mCharacterIndex will be greater than mPreviousNumberOfCharacters.
+ // Which apply an assumption to update only the last paragraph. That could cause many of out of index crashes.
+ textUpdateInfo.mCharacterIndex = updateInfoCharIndexBackup;
+
+ // Do not do again the only once operations.
+ operationsPending = static_cast<OperationsMask>(operationsPending & ~onlyOnceOperations);
+
+ // Do the size related operations again.
+
+ const OperationsMask sizeOperations = static_cast<OperationsMask>(LAYOUT |
+ ALIGN |
+ REORDER);
+
+ operationsPending = static_cast<OperationsMask>(operationsPending | sizeOperations);
+
+ // Restore the actual control's size.
+ visualModel->mControlSize = actualControlSize;
+
+ return calculatedLayoutSize;
+}
+