text: drop unused line.bounds

This commit removes the logic that calculates the bounding box of a line.
We don't actually use this information anywhere, so computing it is just
a waste of CPU and memory. Widgets arrive at their own bounding boxes from
consuming the glyph stream anyway.

Signed-off-by: Chris Waldon <christopher.waldon.dev@gmail.com>

text/gotext.go

@@ -82,8 +82,6 @@ type line struct {
 	// lineHeight captures the gap that should exist between the baseline of this
 	// line and the previous (if any).
 	lineHeight fixed.Int26_6
-	// bounds is the visible bounds of the line.
-	bounds fixed.Rectangle26_6
 	// direction is the dominant direction of the line. This direction will be
 	// used to align the text content of the line, but may not match the actual
 	// direction of the runs of text within the line (such as an RTL sentence
@@ -888,13 +886,6 @@ func toLine(faceToIndex map[font.Font]int, o shaping.Line, dir system.TextDirect
 			PPEM:      run.Size,
 		}
 		line.runeCount += run.Runes.Count
-		if line.bounds.Min.Y > -run.LineBounds.Ascent {
-			line.bounds.Min.Y = -run.LineBounds.Ascent
-		}
-		if line.bounds.Max.Y < -run.LineBounds.Ascent+run.LineBounds.LineHeight() {
-			line.bounds.Max.Y = -run.LineBounds.Ascent + run.LineBounds.LineHeight()
-		}
-		line.bounds.Max.X += run.Advance
 		line.width += run.Advance
 		if line.ascent < run.LineBounds.Ascent {
 			line.ascent = run.LineBounds.Ascent
@@ -905,20 +896,6 @@ func toLine(faceToIndex map[font.Font]int, o shaping.Line, dir system.TextDirect
 	}
 	line.lineHeight = maxSize
 	computeVisualOrder(&line)
-	// Account for glyphs hanging off of either side in the bounds.
-	if len(line.visualOrder) > 0 {
-		runIdx := line.visualOrder[0]
-		run := o[runIdx]
-		if len(run.Glyphs) > 0 {
-			line.bounds.Min.X = run.Glyphs[0].LeftSideBearing()
-		}
-		runIdx = line.visualOrder[len(line.visualOrder)-1]
-		run = o[runIdx]
-		if len(run.Glyphs) > 0 {
-			lastGlyphIdx := len(run.Glyphs) - 1
-			line.bounds.Max.X += run.Glyphs[lastGlyphIdx].RightSideBearing()
-		}
-	}
 	return line
 }
 

text/gotext_test.go

@@ -52,16 +52,11 @@ func TestEmptyString(t *testing.T) {
 		t.Fatalf("Layout returned no lines for empty string; expected 1")
 	}
 	l := lines.lines[0]
-	exp := fixed.Rectangle26_6{
+	if expected := fixed.Int26_6(12094); l.ascent != expected {
-		Min: fixed.Point26_6{
+		t.Errorf("unexpected ascent for empty string: %v, expected %v", l.ascent, expected)
-			Y: fixed.Int26_6(-12094),
-		},
-		Max: fixed.Point26_6{
-			Y: fixed.Int26_6(2700),
-		},
 	}
-	if got := l.bounds; got != exp {
+	if expected := fixed.Int26_6(2700); l.descent != expected {
-		t.Errorf("got bounds %+v for empty string; expected %+v", got, exp)
+		t.Errorf("unexpected descent for empty string: %v, expected %v", l.descent, expected)
 	}
 }
 
@@ -392,12 +387,6 @@ func TestToLine(t *testing.T) {
 					totalInputRunes += run.Runes.Count
 				}
 				output := toLine(shaper.faceToIndex, input, tc.dir)
-				if output.bounds.Min == (fixed.Point26_6{}) {
-					t.Errorf("line %d: Bounds.Min not populated", i)
-				}
-				if output.bounds.Max == (fixed.Point26_6{}) {
-					t.Errorf("line %d: Bounds.Max not populated", i)
-				}
 				if output.direction != tc.dir {
 					t.Errorf("line %d: expected direction %v, got %v", i, tc.dir, output.direction)
 				}
@@ -604,12 +593,6 @@ func validateLines(t *testing.T, lines []line, expectedRuneCount int) {
 	t.Helper()
 	runesSeen := 0
 	for i, line := range lines {
-		if line.bounds.Min == (fixed.Point26_6{}) {
-			t.Errorf("line %d: Bounds.Min not populated", i)
-		}
-		if line.bounds.Max == (fixed.Point26_6{}) {
-			t.Errorf("line %d: Bounds.Max not populated", i)
-		}
 		totalRunWidth := fixed.I(0)
 		totalLineGlyphs := 0
 		lineRunesSeen := 0