| public GetNextCaretPosition ( int visualColumn, LogicalDirection direction, CaretPositioningMode mode ) : int | ||
| visualColumn | int | |
| direction | LogicalDirection | |
| mode | CaretPositioningMode | |
| return | int | |
/// <summary>
/// Validates the visual column of the caret using the specified visual line.
/// The visual line must contain the caret offset.
/// </summary>
void RevalidateVisualColumn(VisualLine visualLine)
{
if (visualLine == null)
throw new ArgumentNullException("visualLine");
// mark column as validated
visualColumnValid = true;
int caretOffset = textView.Document.GetOffset(position.Location);
int firstDocumentLineOffset = visualLine.FirstDocumentLine.Offset;
position.VisualColumn = visualLine.ValidateVisualColumn(position, textArea.Selection.EnableVirtualSpace);
// search possible caret positions
int newVisualColumnForwards = visualLine.GetNextCaretPosition(position.VisualColumn - 1, LogicalDirection.Forward, CaretPositioningMode.Normal, textArea.Selection.EnableVirtualSpace);
// If position.VisualColumn was valid, we're done with validation.
if (newVisualColumnForwards != position.VisualColumn) {
// also search backwards so that we can pick the better match
int newVisualColumnBackwards = visualLine.GetNextCaretPosition(position.VisualColumn + 1, LogicalDirection.Backward, CaretPositioningMode.Normal, textArea.Selection.EnableVirtualSpace);
if (newVisualColumnForwards < 0 && newVisualColumnBackwards < 0)
throw ThrowUtil.NoValidCaretPosition();
// determine offsets for new visual column positions
int newOffsetForwards;
if (newVisualColumnForwards >= 0)
newOffsetForwards = visualLine.GetRelativeOffset(newVisualColumnForwards) + firstDocumentLineOffset;
else
newOffsetForwards = -1;
int newOffsetBackwards;
if (newVisualColumnBackwards >= 0)
newOffsetBackwards = visualLine.GetRelativeOffset(newVisualColumnBackwards) + firstDocumentLineOffset;
else
newOffsetBackwards = -1;
int newVisualColumn, newOffset;
// if there's only one valid position, use it
if (newVisualColumnForwards < 0) {
newVisualColumn = newVisualColumnBackwards;
newOffset = newOffsetBackwards;
} else if (newVisualColumnBackwards < 0) {
newVisualColumn = newVisualColumnForwards;
newOffset = newOffsetForwards;
} else {
// two valid positions: find the better match
if (Math.Abs(newOffsetBackwards - caretOffset) < Math.Abs(newOffsetForwards - caretOffset)) {
// backwards is better
newVisualColumn = newVisualColumnBackwards;
newOffset = newOffsetBackwards;
} else {
// forwards is better
newVisualColumn = newVisualColumnForwards;
newOffset = newOffsetForwards;
}
}
this.Position = new TextViewPosition(textView.Document.GetLocation(newOffset), newVisualColumn);
}
}
Rect CalcCaretOverstrikeRectangle(VisualLine visualLine)
{
if (!visualColumnValid) {
RevalidateVisualColumn(visualLine);
}
int currentPos = position.VisualColumn;
// The text being overwritten in overstrike mode is everything up to the next normal caret stop
int nextPos = visualLine.GetNextCaretPosition(currentPos, LogicalDirection.Forward, CaretPositioningMode.Normal, true);
TextLine textLine = visualLine.GetTextLine(currentPos);
Rect r;
if (currentPos < visualLine.VisualLength) {
// If the caret is within the text, use GetTextBounds() for the text being overwritten.
// This is necessary to ensure the rectangle is calculated correctly in bidirectional text.
var textBounds = textLine.GetTextBounds(currentPos, nextPos - currentPos)[0];
r = textBounds.Rectangle;
r.Y += visualLine.GetTextLineVisualYPosition(textLine, VisualYPosition.LineTop);
} else {
// If the caret is at the end of the line (or in virtual space),
// use the visual X position of currentPos and nextPos (one or more of which will be in virtual space)
double xPos = visualLine.GetTextLineVisualXPosition(textLine, currentPos);
double xPos2 = visualLine.GetTextLineVisualXPosition(textLine, nextPos);
double lineTop = visualLine.GetTextLineVisualYPosition(textLine, VisualYPosition.TextTop);
double lineBottom = visualLine.GetTextLineVisualYPosition(textLine, VisualYPosition.TextBottom);
r = new Rect(xPos, lineTop, xPos2 - xPos, lineBottom - lineTop);
}
// If the caret is too small (e.g. in front of zero-width character), ensure it's still visible
if (r.Width < SystemParameters.CaretWidth)
r.Width = SystemParameters.CaretWidth;
return r;
}
static TextViewPosition GetPrevCaretPosition(TextView textView, TextViewPosition caretPosition, VisualLine visualLine, CaretPositioningMode mode, bool enableVirtualSpace) {
int pos = visualLine.GetNextCaretPosition(caretPosition.VisualColumn, LogicalDirection.Backward, mode, enableVirtualSpace);
if (pos >= 0)
return visualLine.GetTextViewPosition(pos);
var previousDocumentLine = visualLine.FirstDocumentLine.PreviousLine;
if (previousDocumentLine != null) {
var previousLine = textView.GetOrConstructVisualLine(previousDocumentLine);
pos = previousLine.GetNextCaretPosition(previousLine.VisualLength + 1, LogicalDirection.Backward, mode, enableVirtualSpace);
return previousLine.GetTextViewPosition(pos);
}
return new TextViewPosition(0, 0);
}
static void MoveCaretRight(TextArea textArea, TextViewPosition caretPosition, VisualLine visualLine, CaretPositioningMode mode)
{
int pos = visualLine.GetNextCaretPosition(caretPosition.VisualColumn, LogicalDirection.Forward, mode);
if (pos >= 0) {
SetCaretPosition(textArea, pos, visualLine.GetRelativeOffset(pos) + visualLine.FirstDocumentLine.Offset);
} else {
// move to start of next line
DocumentLine nextDocumentLine = visualLine.LastDocumentLine.NextLine;
if (nextDocumentLine != null) {
VisualLine nextLine = textArea.TextView.GetOrConstructVisualLine(nextDocumentLine);
pos = nextLine.GetNextCaretPosition(-1, LogicalDirection.Forward, mode);
if (pos < 0)
throw ThrowUtil.NoValidCaretPosition();
SetCaretPosition(textArea, pos, nextLine.GetRelativeOffset(pos) + nextLine.FirstDocumentLine.Offset);
} else {
// at end of document
Debug.Assert(visualLine.LastDocumentLine.Offset + visualLine.LastDocumentLine.TotalLength == textArea.Document.TextLength);
SetCaretPosition(textArea, -1, textArea.Document.TextLength);
}
}
}
static void MoveCaretToStartOfLine(TextArea textArea, VisualLine visualLine)
{
int newVC = visualLine.GetNextCaretPosition(-1, LogicalDirection.Forward, CaretPositioningMode.WordStart);
if (newVC < 0)
throw ThrowUtil.NoValidCaretPosition();
// when the caret is already at the start of the text, jump to start before whitespace
if (newVC == textArea.Caret.VisualColumn)
newVC = 0;
int offset = visualLine.FirstDocumentLine.Offset + visualLine.GetRelativeOffset(newVC);
SetCaretPosition(textArea, newVC, offset);
}
static void MoveCaretLeft(TextArea textArea, TextViewPosition caretPosition, VisualLine visualLine, CaretPositioningMode mode)
{
int pos = visualLine.GetNextCaretPosition(caretPosition.VisualColumn, LogicalDirection.Backward, mode);
if (pos >= 0) {
SetCaretPosition(textArea, pos, visualLine.GetRelativeOffset(pos) + visualLine.FirstDocumentLine.Offset);
} else {
// move to end of previous line
DocumentLine previousDocumentLine = visualLine.FirstDocumentLine.PreviousLine;
if (previousDocumentLine != null) {
VisualLine previousLine = textArea.TextView.GetOrConstructVisualLine(previousDocumentLine);
pos = previousLine.GetNextCaretPosition(previousLine.VisualLength + 1, LogicalDirection.Backward, mode);
if (pos < 0)
throw ThrowUtil.NoValidCaretPosition();
SetCaretPosition(textArea, pos, previousLine.GetRelativeOffset(pos) + previousLine.FirstDocumentLine.Offset);
} else {
// at start of document
Debug.Assert(visualLine.FirstDocumentLine.Offset == 0);
SetCaretPosition(textArea, 0, 0);
}
}
}
static TextViewPosition GetPrevCaretPosition(TextView textView, TextViewPosition caretPosition, VisualLine visualLine, CaretPositioningMode mode, bool enableVirtualSpace)
{
int pos = visualLine.GetNextCaretPosition(caretPosition.VisualColumn, LogicalDirection.Backward, mode, enableVirtualSpace);
if (pos >= 0) {
return visualLine.GetTextViewPosition(pos);
} else {
// move to end of previous line
DocumentLine previousDocumentLine = visualLine.FirstDocumentLine.PreviousLine;
if (previousDocumentLine != null) {
VisualLine previousLine = textView.GetOrConstructVisualLine(previousDocumentLine);
pos = previousLine.GetNextCaretPosition(previousLine.VisualLength + 1, LogicalDirection.Backward, mode, enableVirtualSpace);
if (pos < 0)
throw ThrowUtil.NoValidCaretPosition();
return previousLine.GetTextViewPosition(pos);
} else {
// at start of document
Debug.Assert(visualLine.FirstDocumentLine.Offset == 0);
return new TextViewPosition(0, 0);
}
}
}
static TextViewPosition GetNextCaretPosition(TextView textView, TextViewPosition caretPosition, VisualLine visualLine, CaretPositioningMode mode, bool enableVirtualSpace)
{
int pos = visualLine.GetNextCaretPosition(caretPosition.VisualColumn, LogicalDirection.Forward, mode, enableVirtualSpace);
if (pos >= 0) {
return visualLine.GetTextViewPosition(pos);
} else {
// move to start of next line
DocumentLine nextDocumentLine = visualLine.LastDocumentLine.NextLine;
if (nextDocumentLine != null) {
VisualLine nextLine = textView.GetOrConstructVisualLine(nextDocumentLine);
pos = nextLine.GetNextCaretPosition(-1, LogicalDirection.Forward, mode, enableVirtualSpace);
if (pos < 0)
throw ThrowUtil.NoValidCaretPosition();
return nextLine.GetTextViewPosition(pos);
} else {
// at end of document
Debug.Assert(visualLine.LastDocumentLine.Offset + visualLine.LastDocumentLine.TotalLength == textView.Document.TextLength);
return new TextViewPosition(textView.Document.GetLocation(textView.Document.TextLength));
}
}
}
static TextViewPosition GetStartOfLineCaretPosition(int oldVC, VisualLine visualLine, TextLine textLine, bool enableVirtualSpace)
{
int newVC = visualLine.GetTextLineVisualStartColumn(textLine);
if (newVC == 0)
newVC = visualLine.GetNextCaretPosition(newVC - 1, LogicalDirection.Forward, CaretPositioningMode.WordStart, enableVirtualSpace);
if (newVC < 0)
throw ThrowUtil.NoValidCaretPosition();
// when the caret is already at the start of the text, jump to start before whitespace
if (newVC == oldVC)
newVC = 0;
return visualLine.GetTextViewPosition(newVC);
}
/// <summary>
/// Validates the visual column of the caret using the specified visual line.
/// The visual line must contain the caret offset.
/// </summary>
void RevalidateVisualColumn(VisualLine visualLine)
{
if (visualLine == null)
throw new ArgumentNullException("visualLine");
// mark column as validated
visualColumnValid = true;
int caretOffset = textView.Document.GetOffset(position);
int firstDocumentLineOffset = visualLine.FirstDocumentLine.Offset;
if (position.VisualColumn < 0) {
position.VisualColumn = visualLine.GetVisualColumn(caretOffset - firstDocumentLineOffset);
} else {
int offsetFromVisualColumn = visualLine.GetRelativeOffset(position.VisualColumn);
offsetFromVisualColumn += firstDocumentLineOffset;
if (offsetFromVisualColumn != caretOffset) {
position.VisualColumn = visualLine.GetVisualColumn(caretOffset - firstDocumentLineOffset);
} else {
if (position.VisualColumn > visualLine.VisualLength) {
position.VisualColumn = visualLine.VisualLength;
}
}
}
// search possible caret position (first try forwards)
int newVisualColumn = visualLine.GetNextCaretPosition(position.VisualColumn - 1, LogicalDirection.Forward, CaretPositioningMode.Normal);
if (newVisualColumn < 0) {
// then try backwards
newVisualColumn = visualLine.GetNextCaretPosition(position.VisualColumn + 1, LogicalDirection.Backward, CaretPositioningMode.Normal);
}
if (newVisualColumn < 0)
throw ThrowUtil.NoValidCaretPosition();
if (newVisualColumn != position.VisualColumn) {
int newOffset = visualLine.GetRelativeOffset(newVisualColumn) + firstDocumentLineOffset;
this.Position = new TextViewPosition(textView.Document.GetLocation(newOffset), newVisualColumn);
}
}
