Пример #1
0
        private void Paint(SKCanvasView canvasView)
        {
            using (var recorder = new SKPictureRecorder())
                using (var canvas = recorder.BeginRecording(SKRect.Create(SKPoint.Empty, Size)))
                {
                    try
                    {
                        Page.Render(canvas, Size);
                    }
                    catch (Exception ex)
                    {
                        using (var paint = new SKPaint {
                            Color = SKColors.DarkRed
                        })
                        {
                            canvas.Save();
                            if (canvas.TotalMatrix.ScaleY < 0)
                            {
                                var matrix = SKMatrix.MakeScale(1, -1);
                                canvas.Concat(ref matrix);
                            }
                            canvas.DrawText(ex.Message, 0, 0, paint);
                            canvas.Restore();
                        }
                    }
                    picture = recorder.EndRecording();
                }
            //text
            var positionComparator = new TextStringPositionComparer <ITextString>();

            Page.Strings.Sort(positionComparator);

            Xamarin.Forms.Device.BeginInvokeOnMainThread(() => canvasView.InvalidateSurface());
        }
Пример #2
0
        /**
         * <summary>Sorts the extracted text strings.</summary>
         * <remarks>Sorting implies text position ordering, integration and aggregation.</remarks>
         * <param name="rawTextStrings">Source (lower-level) text strings.</param>
         * <param name="textStrings">Target (higher-level) text strings.</param>
         */
        private void Sort(
            List <ContentScanner.TextStringWrapper> rawTextStrings,
            List <ITextString> textStrings
            )
        {
            // Sorting the source text strings...
            {
                TextStringPositionComparer <ContentScanner.TextStringWrapper> positionComparator = new TextStringPositionComparer <ContentScanner.TextStringWrapper>();
                rawTextStrings.Sort(positionComparator);
            }

            // Aggregating and integrating the source text strings into the target ones...
            TextString textString       = null;
            TextStyle  textStyle        = null;
            TextChar   previousTextChar = null;
            bool       dehyphenating    = false;

            foreach (ContentScanner.TextStringWrapper rawTextString in rawTextStrings)
            {
                /*
                 * NOTE: Contents on the same line are grouped together within the same text string.
                 */
                // Add a new text string in case of new line!
                if (textString != null &&
                    textString.TextChars.Count > 0 &&
                    !TextStringPositionComparer <ITextString> .IsOnTheSameLine(textString.Box.Value, rawTextString.Box.Value))
                {
                    if (dehyphenated &&
                        previousTextChar.Value == '-') // Hyphened word.
                    {
                        textString.TextChars.Remove(previousTextChar);
                        dehyphenating = true;
                    }
                    else // Full word.
                    {
                        // Add synthesized space character!
                        textString.TextChars.Add(
                            new TextChar(
                                ' ',
                                new RectangleF(
                                    previousTextChar.Box.Right,
                                    previousTextChar.Box.Top,
                                    0,
                                    previousTextChar.Box.Height
                                    ),
                                textStyle,
                                true
                                )
                            );
                        textString    = null;
                        dehyphenating = false;
                    }
                    previousTextChar = null;
                }
                if (textString == null)
                {
                    textStrings.Add(textString = new TextString());
                }

                textStyle = rawTextString.Style;
                double spaceWidth = textStyle.GetWidth(' ') * .5;
                foreach (TextChar textChar in rawTextString.TextChars)
                {
                    if (previousTextChar != null)
                    {
                        /*
                         * NOTE: PDF files may have text contents omitting space characters,
                         * so they must be inferred and synthesized, marking them as virtual
                         * in order to allow the user to distinguish between original contents
                         * and augmented ones.
                         */
                        if (!textChar.Contains(' ') &&
                            !previousTextChar.Contains(' '))
                        {
                            float charSpace = textChar.Box.X - previousTextChar.Box.Right;
                            if (charSpace > spaceWidth)
                            {
                                // Add synthesized space character!
                                textString.TextChars.Add(
                                    previousTextChar = new TextChar(
                                        ' ',
                                        new RectangleF(
                                            previousTextChar.Box.Right,
                                            textChar.Box.Y,
                                            charSpace,
                                            textChar.Box.Height
                                            ),
                                        textStyle,
                                        true
                                        )
                                    );
                            }
                        }
                        else if (dehyphenating &&
                                 previousTextChar.Contains(' '))
                        {
                            textStrings.Add(textString = new TextString());
                            dehyphenating = false;
                        }
                    }
                    textString.TextChars.Add(previousTextChar = textChar);
                }
            }
        }
Пример #3
0
        /**
         * <summary>Sorts the extracted text strings.</summary>
         * <remarks>Sorting implies text position ordering, integration and aggregation.</remarks>
         * <param name="rawTextStrings">Source (lower-level) text strings.</param>
         * <param name="textStrings">Target (higher-level) text strings.</param>
         */
        private void Sort(
            List <ContentScanner.TextStringWrapper> rawTextStrings,
            List <ITextString> textStrings
            )
        {
            // Sorting the source text strings...
            {
                TextStringPositionComparer <ContentScanner.TextStringWrapper> positionComparator = new TextStringPositionComparer <ContentScanner.TextStringWrapper>();
                rawTextStrings.Sort(positionComparator);
            }

            // Aggregating and integrating the source text strings into the target ones...
            TextString textString       = null;
            TextChar   previousTextChar = null;

            foreach (ContentScanner.TextStringWrapper rawTextString in rawTextStrings)
            {
                /*
                 * NOTE: Contents on the same line are grouped together within the same text string.
                 */
                // Add a new text string in case of new line!
                if (textString == null ||
                    (textString.TextChars.Count > 0 &&
                     !TextStringPositionComparer <ITextString> .IsOnTheSameLine(
                         textString.Box.Value,
                         rawTextString.Box.Value)))
                {
                    textStrings.Add(textString = new TextString());
                    previousTextChar           = null;
                }

                TextStyle textStyle  = rawTextString.Style;
                float     spaceWidth = 0;
                try
                { spaceWidth = textStyle.Font.GetWidth(' ', textStyle.FontSize); }
                catch
                { /* NOOP. */ }
                if (spaceWidth == 0)
                {
                    spaceWidth = textStyle.FontSize * .25f;
                }                                 // NOTE: as a rule of thumb, space width is estimated according to the font size.
                foreach (TextChar textChar in rawTextString.TextChars)
                {
                    if (previousTextChar != null)
                    {
                        /*
                         * NOTE: PDF files may have text contents omitting space characters,
                         * so they must be inferred and synthesized, marking them as virtual
                         * in order to allow the user to distinguish between original contents
                         * and augmented ones.
                         */
                        float characterSpace = textChar.Box.X - previousTextChar.Box.Right;
                        if (characterSpace >= spaceWidth)
                        {
                            // Add synthesized space character!
                            textString.TextChars.Add(
                                new TextChar(
                                    ' ',
                                    new RectangleF(
                                        previousTextChar.Box.Right,
                                        textChar.Box.Y,
                                        characterSpace,
                                        textChar.Box.Height
                                        ),
                                    textStyle,
                                    true
                                    )
                                );
                        }
                    }
                    textString.TextChars.Add(previousTextChar = textChar);
                }
            }
        }