GH-221 Draw word-wise to take ligatures into account

SwiftNeoVim/Grid.swift

@@ -83,7 +83,7 @@ struct Region: CustomStringConvertible {
 
 /// Almost a verbatim copy of ugrid.c of NeoVim
 class Grid: CustomStringConvertible {
-  
+
   private(set) var region = Region.zero
   private(set) var size = Size.zero
   private(set) var putPosition = Position.zero
@@ -201,6 +201,32 @@ class Grid: CustomStringConvertible {
     return position.row * self.size.width + position.column
   }
 
+  func regionOfCurrentWord(position: Position) -> Region {
+    let row = position.row
+    let column = position.column
+    
+//    NSLog("current char: '\(self.cells[row][column])'")
+
+    var left = 0
+    for (idx, cell) in self.cells[row][0...column].enumerate().reverse() {
+      if cell.string == " " || cell.string == "" {
+        left = idx
+        break
+      }
+    }
+    
+    var right = self.region.right
+    for idx in column..<self.size.width {
+      let cell = self.cells[row][idx]
+      if cell.string == " " || cell.string == "" {
+        right = idx
+        break
+      }
+    }
+    
+    return Region(top: row, bottom: row, left: left, right: right)
+  }
+
   func positionFromSingleIndex(idx: Int) -> Position {
     let row = Int(floor(Double(idx) / Double(self.size.width)))
     let column = idx - row * self.size.width

SwiftNeoVim/NeoVimView.swift

@@ -63,8 +63,9 @@ public class NeoVimView: NSView {
   private var pinchTargetScale = CGFloat(1)
   private var pinchImage = NSImage()
   
-  public var useLigatures = false {
+  public var usesLigatures = false {
     didSet {
+      self.drawer.usesLigatures = self.usesLigatures
       self.needsDisplay = true
     }
   }
@@ -180,6 +181,7 @@ public class NeoVimView: NSView {
     CGContextSetTextDrawingMode(context, .Fill);
 
     let dirtyRects = self.rectsBeingDrawn()
+//    NSLog("\(dirtyRects)")
 
     self.rowRunIntersecting(rects: dirtyRects).forEach { rowFrag in
       // For background drawing we don't filter out the put(0, 0)s: in some cases only the put(0, 0)-cells should be
@@ -292,8 +294,8 @@ public class NeoVimView: NSView {
 
   private func pointInViewFor(row row: Int, column: Int) -> CGPoint {
     return CGPoint(
-      x: CGFloat(column) * self.cellSize.width + self.xOffset,
-      y: self.frame.size.height - CGFloat(row) * self.cellSize.height - self.cellSize.height - self.yOffset
+      x: self.xOffset + CGFloat(column) * self.cellSize.width,
+      y: self.frame.size.height - self.yOffset - CGFloat(row) * self.cellSize.height - self.cellSize.height
     )
   }
 
@@ -310,11 +312,14 @@ public class NeoVimView: NSView {
     let width = right - left + 1
     let height = bottom - top + 1
 
+    let cellWidth = self.cellSize.width
+    let cellHeight = self.cellSize.height
+
     return CGRect(
-      x: left * self.cellSize.width + self.xOffset,
-      y: (CGFloat(self.grid.size.height) - bottom) * self.cellSize.height - self.yOffset,
-      width: width * self.cellSize.width,
-      height: height * self.cellSize.height
+      x: self.xOffset + left * cellWidth,
+      y: self.bounds.size.height - self.yOffset - top * cellHeight - height * cellHeight,
+      width: width * cellWidth,
+      height: height * cellHeight
     )
   }
 
@@ -849,10 +854,19 @@ extension NeoVimView: NeoVimUiBridgeProtocol {
       let curPos = self.grid.putPosition
 //      NSLog("\(#function): \(curPos) -> \(string)")
       self.grid.put(string)
-      self.setNeedsDisplay(cellPosition: curPos)
+
+      if self.usesLigatures {
+        if string == " " {
+          self.setNeedsDisplay(cellPosition: curPos)
+        } else {
+          self.setNeedsDisplay(region: self.grid.regionOfCurrentWord(curPos))
+        }
+      } else {
+        self.setNeedsDisplay(cellPosition: curPos)
+      }
+
       // When the cursor is in the command line, then we need this...
       self.setNeedsDisplay(cellPosition: self.grid.nextCellPosition(curPos))
-
       self.setNeedsDisplay(screenCursor: self.grid.screenCursor)
     }
   }

SwiftNeoVim/TextDrawer.h

@@ -11,7 +11,7 @@
 @interface TextDrawer : NSObject
 
 @property (nonatomic, nonnull, retain) NSFont *font;
-@property (nonatomic) bool useLigatures;
+@property (nonatomic) bool usesLigatures;
 @property (nonatomic, readonly) CGFloat leading;
 @property (nonatomic, readonly) CGFloat descent;
 @property (nonatomic, readonly) CGSize cellSize;

SwiftNeoVim/TextDrawer.m

@@ -57,7 +57,7 @@
     return nil;
   }
 
-  _useLigatures = useLigatures;
+  _usesLigatures = useLigatures;
   _layoutManager = [[NSLayoutManager alloc] init];
   _fontLookupCache = [[NSMutableArray alloc] init];
   _fontTraitCache = [[NSMutableDictionary alloc] init];
@@ -135,7 +135,7 @@
   CTFontRef fontWithTraits = [self fontWithTrait:fontTrait];
 
   CGContextSetRGBFillColor(context, RED(foreground), GREEN(foreground), BLUE(foreground), 1.0);
-  recurseDraw(unichars, glyphs, positions, unilength, context, fontWithTraits, _fontLookupCache, _useLigatures);
+  recurseDraw(unichars, glyphs, positions, unilength, context, fontWithTraits, _fontLookupCache, _usesLigatures);
 
   CFRelease(fontWithTraits);
   free(glyphs);

VimR/AppearancePrefPane.swift

@@ -35,6 +35,7 @@ class AppearancePrefPane: NSView, NSComboBoxDelegate, NSControlTextEditingDelega
   private var font: NSFont
   private var fontSize = CGFloat(13)
   private var fontName = "Menlo"
+  private var usesLigatures = false
 
   // Return true to place this to the upper left corner when the scroll view is bigger than this view.
   override var flipped: Bool {
@@ -47,6 +48,7 @@ class AppearancePrefPane: NSView, NSComboBoxDelegate, NSControlTextEditingDelega
     self.font = initialData.editorFont
     self.fontSize = initialData.editorFont.pointSize
     self.fontName = initialData.editorFont.fontName
+    self.usesLigatures = initialData.editorUsesLigatures
 
     super.init(frame: CGRect.zero)
     self.translatesAutoresizingMaskIntoConstraints = false
@@ -164,6 +166,7 @@ class AppearancePrefPane: NSView, NSComboBoxDelegate, NSControlTextEditingDelega
   private func updateViews() {
     self.fontPopup.selectItemWithTitle(self.fontName)
     self.sizeCombo.stringValue = String(Int(self.fontSize))
+    self.ligatureCheckbox.state = self.usesLigatures ? NSOnState : NSOffState
     self.previewArea.font = self.font
   }
 }

VimR/MainWindowComponent.swift

@@ -24,6 +24,7 @@ class MainWindowComponent: NSObject, NSWindowDelegate, NeoVimViewDelegate, Compo
   private let window: NSWindow
 
   private var defaultEditorFont: NSFont
+  private var usesLigatures: Bool
 
   var uuid: String {
     return self.neoVimView.uuid
@@ -36,6 +37,7 @@ class MainWindowComponent: NSObject, NSWindowDelegate, NeoVimViewDelegate, Compo
     self.mainWindowManager = manager
     self.window = self.windowController.window!
     self.defaultEditorFont = initialData.appearance.editorFont
+    self.usesLigatures = initialData.appearance.editorUsesLigatures
 
     super.init()
 
@@ -66,9 +68,10 @@ class MainWindowComponent: NSObject, NSWindowDelegate, NeoVimViewDelegate, Compo
   private func addReactions() {
     self.source
       .filter { $0 is PrefData }
-      .map { ($0 as! PrefData).appearance.editorFont }
-      .subscribeNext { [unowned self] font in
-        self.neoVimView.font = font
+      .map { ($0 as! PrefData).appearance }
+      .subscribeNext { [unowned self] appearance in
+        self.neoVimView.usesLigatures = appearance.editorUsesLigatures
+        self.neoVimView.font = appearance.editorFont
       }
       .addDisposableTo(self.disposeBag)
   }
@@ -105,6 +108,7 @@ extension MainWindowComponent {
 
   func neoVimReady() {
     self.neoVimView.font = self.defaultEditorFont
+    self.neoVimView.usesLigatures = self.usesLigatures
   }
   
   func neoVimStopped() {

VimR/PrefStore.swift

@@ -79,8 +79,9 @@ class PrefStore: Store {
   private func prefsDict(prefData: PrefData) -> [String: AnyObject] {
     let appearanceData = prefData.appearance
     let prefs: [String: AnyObject] = [
-        PrefKeys.editorFontName: appearanceData.editorFont.fontName,
-        PrefKeys.editorFontSize: appearanceData.editorFont.pointSize
+      PrefKeys.editorFontName: appearanceData.editorFont.fontName,
+      PrefKeys.editorFontSize: appearanceData.editorFont.pointSize,
+      PrefKeys.editorUsesLigatures: appearanceData.editorUsesLigatures
     ]
     return prefs
   }