/**
* Draw the given line range.
*
* @param gc
* @param startLine first line number
* @param endLine last line number (inclusive)
* @param x the X-coordinate of the drawing range
* @param w the width of the drawing range
*/
private void drawLineRange(GC gc, int startLine, int endLine, int x, int w) {
final int viewPortWidth = fTextWidget.getClientArea().width;
for (int line = startLine; line <= endLine; line++) {
int lineOffset = fTextWidget.getOffsetAtLine(line);
// line end offset including line delimiter
int lineEndOffset;
if (line < fTextWidget.getLineCount() - 1) {
lineEndOffset = fTextWidget.getOffsetAtLine(line + 1);
} else {
lineEndOffset = fTextWidget.getCharCount();
}
// line length excluding line delimiter
int lineLength = lineEndOffset - lineOffset;
while (lineLength > 0) {
char c = fTextWidget.getTextRange(lineOffset + lineLength - 1, 1).charAt(0);
if (c != '\r' && c != '\n') {
break;
}
--lineLength;
}
// compute coordinates of last character on line
Point endOfLine = fTextWidget.getLocationAtOffset(lineOffset + lineLength);
if (x - endOfLine.x > viewPortWidth) {
// line is not visible
continue;
}
// Y-coordinate of line
int y = fTextWidget.getLinePixel(line);
// compute first visible char offset
int startOffset;
try {
startOffset = fTextWidget.getOffsetAtLocation(new Point(x, y)) - 1;
if (startOffset - 2 <= lineOffset) {
startOffset = lineOffset;
}
} catch (IllegalArgumentException iae) {
startOffset = lineOffset;
}
// compute last visible char offset
int endOffset;
if (x + w >= endOfLine.x) {
// line end is visible
endOffset = lineEndOffset;
} else {
try {
endOffset = fTextWidget.getOffsetAtLocation(new Point(x + w - 1, y)) + 1;
if (endOffset + 2 >= lineEndOffset) {
endOffset = lineEndOffset;
}
} catch (IllegalArgumentException iae) {
endOffset = lineEndOffset;
}
}
// draw character range
if (endOffset > startOffset) {
drawCharRange(gc, startOffset, endOffset);
}
}
}
/**
* Convert mouse screen coordinates to a <code>StyledText</code> offset.
*
* @param x screen X-coordinate
* @param y screen Y-coordinate
* @param absolute if <code>true</code>, coordinates are expected to be absolute screen
* coordinates
* @return text offset
* @see StyledText#getOffsetAtLocation()
*/
private int getOffsetAtLocation(int x, int y, boolean absolute) {
StyledText textWidget = fViewer.getTextWidget();
StyledTextContent content = textWidget.getContent();
Point location;
if (absolute) {
location = textWidget.toControl(x, y);
} else {
location = new Point(x, y);
}
int line = (textWidget.getTopPixel() + location.y) / textWidget.getLineHeight();
if (line >= content.getLineCount()) {
return content.getCharCount();
}
int lineOffset = content.getOffsetAtLine(line);
String lineText = content.getLine(line);
Point endOfLine = textWidget.getLocationAtOffset(lineOffset + lineText.length());
if (location.x >= endOfLine.x) {
return lineOffset + lineText.length();
}
try {
return textWidget.getOffsetAtLocation(location);
} catch (IllegalArgumentException iae) {
// we are expecting this
return -1;
}
}
/**
* Get style range at x/y coordinates
*
* @param x
* @param y
* @return style range, will be null when no style range exists at given coordinates
*/
private StyleRange getStyleRange(final int x, final int y) {
final StyledText t = getTextWidget();
final int offset;
try {
offset = t.getOffsetAtLocation(new Point(x, y));
} catch (IllegalArgumentException e) {
return null;
}
if (offset < t.getCharCount()) return t.getStyleRangeAtOffset(offset);
else return null;
}
// modified version from TextViewer
private int computeOffsetAtLocation(ITextViewer textViewer, int x, int y) {
StyledText styledText = textViewer.getTextWidget();
IDocument document = textViewer.getDocument();
if (document == null) return -1;
try {
int widgetOffset = styledText.getOffsetAtLocation(new Point(x, y));
Point p = styledText.getLocationAtOffset(widgetOffset);
if (p.x > x) widgetOffset--;
if (textViewer instanceof ITextViewerExtension5) {
ITextViewerExtension5 extension = (ITextViewerExtension5) textViewer;
return extension.widgetOffset2ModelOffset(widgetOffset);
} else {
IRegion visibleRegion = textViewer.getVisibleRegion();
return widgetOffset + visibleRegion.getOffset();
}
} catch (IllegalArgumentException e) {
return -1;
}
}