wesley/swiftui-math
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Line breaking for fractions and radicals fixes

Browse Source 
Implement smart width-checking for complex mathematical displays to enable
  inline rendering when space permits, dramatically improving multiline layout.

  Changes:
  - Add shouldBreakBeforeDisplay() helper to check width before line breaks
  - Add performLineBreak() helper for clean line transitions
  - Modify fraction handling to stay inline when they fit within maxWidth
  - Modify radical handling to stay inline when they fit within maxWidth
  - Support radicals with degrees (cube roots, nth roots, etc.)
This commit is contained in:
Nicolas Guillot
2025-11-13 15:39:54 +01:00
parent cd9c3f7a37
commit c5b737d9bb
4 changed files with 655 additions and 120 deletions
Download Patch File Download Diff File Expand all files Collapse all files

71
Sources/SwiftMath/MathRender/MTTypesetter.swift
View File

@@ -548,6 +548,38 @@ class MTTypesetter {
return false
}
/// Check if we should break before adding a complex display (fraction, radical, etc.)
/// Returns true if breaking is needed
func shouldBreakBeforeDisplay(_ display: MTDisplay, prevNode: MTMathAtom?, displayType: MTMathAtomType = .ordinary) -> Bool {
// No breaking if no width constraint
guard maxWidth > 0 else { return false }
// No breaking if line is empty
guard currentLine.length > 0 else { return false }
// Calculate spacing between current content and new display
var interElementSpace: CGFloat = 0
if prevNode != nil {
interElementSpace = getInterElementSpace(prevNode!.type, right: displayType)
}
// Calculate projected width
let currentWidth = getCurrentLineWidth()
let projectedWidth = currentWidth + interElementSpace + display.width
// Break only if it would exceed max width
return projectedWidth > maxWidth
}
/// Perform line break for complex displays
func performLineBreak() {
if currentLine.length > 0 {
self.addDisplayLine()
}
currentPosition.y -= styleFont.fontSize * 1.5
currentPosition.x = 0
}
func createDisplayAtoms(_ preprocessed:[MTMathAtom]) {
// items should contain all the nodes that need to be layed out.
@@ -643,22 +675,28 @@ class MTTypesetter {
displayAtoms.append(display!)
case .radical:
// stash the existing layout
if currentLine.length > 0 {
self.addDisplayLine()
}
// Create the radical display first
let rad = atom as! MTRadical
// Radicals are considered as Ord in rule 16.
self.addInterElementSpace(prevNode, currentType:.ordinary)
let displayRad = self.makeRadical(rad.radicand, range:rad.indexRange)
if rad.degree != nil {
// add the degree to the radical
let degree = MTTypesetter.createLineForMathList(rad.degree, font:font, style:.scriptOfScript)
displayRad!.setDegree(degree, fontMetrics:styleFont.mathTable)
}
// Check if we need to break before adding this radical
// Radicals are considered as Ord in rule 16.
if shouldBreakBeforeDisplay(displayRad!, prevNode: prevNode, displayType: .ordinary) {
performLineBreak()
} else {
self.addInterElementSpace(prevNode, currentType:.ordinary)
}
// Position and add the radical display
displayRad!.position = currentPosition
displayAtoms.append(displayRad!)
currentPosition.x += displayRad!.width
// add super scripts || subscripts
if atom.subScript != nil || atom.superScript != nil {
self.makeScripts(atom, display:displayRad, index:UInt(rad.indexRange.location), delta:0)
@@ -667,15 +705,22 @@ class MTTypesetter {
//atom.type = .ordinary;
case .fraction:
// stash the existing layout
if currentLine.length > 0 {
self.addDisplayLine()
}
// Create the fraction display first
let frac = atom as! MTFraction?
self.addInterElementSpace(prevNode, currentType:atom.type)
let display = self.makeFraction(frac)
// Check if we need to break before adding this fraction
if shouldBreakBeforeDisplay(display!, prevNode: prevNode, displayType: atom.type) {
performLineBreak()
} else {
self.addInterElementSpace(prevNode, currentType:atom.type)
}
// Position and add the fraction display
display!.position = currentPosition
displayAtoms.append(display!)
currentPosition.x += display!.width;
currentPosition.x += display!.width
// add super scripts || subscripts
if atom.subScript != nil || atom.superScript != nil {
self.makeScripts(atom, display:display, index:UInt(frac!.indexRange.location), delta:0)