Use OfFloat Point values to create precise highlight brackets

Because of rounding errors the bracket selection highlight is often
inconsistent. Making use of residual values provides precise rectangle
values and highlight is consistent across all zooms

Author: ShahzaibIbrahim

bundles/org.eclipse.jface.text/src/org/eclipse/jface/text/source/MatchingCharacterPainter.java

@@ -14,6 +14,7 @@
 package org.eclipse.jface.text.source;
 
 
+
 import org.eclipse.swt.custom.StyledText;
 import org.eclipse.swt.events.PaintEvent;
 import org.eclipse.swt.events.PaintListener;
@@ -262,12 +263,12 @@ private void draw(final GC gc, final int offset) {
 			// determine the character width separately, because the getTextBounds above
 			// will also include any in-line annotations (e.g. codemining annotations) in the width
 			final String matchingCharacter= fTextWidget.getText(offset, offset);
-			final int width= gc.textExtent(matchingCharacter).x;
+			final Point sizePoints= gc.textExtent(matchingCharacter);
 
-			final int height= fTextWidget.getCaret().getSize().y;
+			Rectangle rectangleOfFloat= Rectangle.of(new Point(bounds.x, bounds.y), sizePoints);
 
 			// draw box around line segment
-			gc.drawRectangle(bounds.x, bounds.y + bounds.height - height, width, height - 1);
+			gc.drawRectangle(rectangleOfFloat);
 		} else {
 			fTextWidget.redrawRange(offset, 1, true);
 		}
@@ -473,4 +474,4 @@ private boolean searchForCharacters(String text, ICharacterPairMatcherExtension
 			return false;
 		}
 	}
-}
+}