Added the MPExpressionTree Classes

MathPad/MPFractionFunctionLayout.m

@@ -0,0 +1,87 @@
+//
+//  MPFractionFunctionLayout.m
+//  MathPad
+//
+//  Created by Kim Wittenburg on 07.10.14.
+//  Copyright (c) 2014 Kim Wittenburg. All rights reserved.
+//
+
+#import "MPFractionFunctionLayout.h"
+#import "MPExpressionLayout.h"
+
+#define kFractionFunctionLineWidth 2
+#define kFractionFunctionHorizontalInset 2
+#define kFractionFunctionNominatorOffset 0
+#define kFractionFunctionDenominatorOffset 0
+
+#define MPFractionMiddle (CTFontGetAscent((CTFontRef)self.font) / 2)
+
+@implementation MPFractionFunctionLayout
+
+- (MPFractionFunction *)fractionFunction
+{
+    return (MPFractionFunction *)self.function;
+}
+
+- (NSUInteger)indexOfChildBelowChildAtIndex:(NSUInteger)index
+{
+    return 1;
+}
+
+- (NSUInteger)indexOfChildAboveChildAtIndex:(NSUInteger)index
+{
+    return 0;
+}
+
+- (NSIndexSet *)indexesOfRemainingChildren
+{
+    return [NSIndexSet indexSetWithIndexesInRange:NSMakeRange(0, 1)];
+}
+
+- (NSPoint)offsetOfChildLayoutAtIndex:(NSUInteger)index
+{
+    if (index == 0) {
+        CGFloat y = MPFractionMiddle + kFractionFunctionLineWidth / 2;
+        return NSMakePoint(0, y);
+    } else {
+        NSRect denominatorBounds = [self childLayoutAtIndex:1].bounds;
+        CGFloat y = CTFontGetAscent((CTFontRef)self.font) / 2 - kFractionFunctionLineWidth / 2;
+        y -= denominatorBounds.size.height - denominatorBounds.origin.y;
+        return NSMakePoint(0, y);
+    }
+}
+
+- (BOOL)childAtIndexUsesSmallSize:(NSUInteger)index
+{
+    return YES;
+}
+
+- (NSIndexPath *)indexPathForLocalMousePoint:(NSPoint)point
+{
+    if (point.x < self.bounds.size.width / 2) {
+        return [NSIndexPath indexPathWithIndex:0];
+    } else {
+        return [NSIndexPath indexPathWithIndex:1];
+    }
+}
+
+- (NSRect)generateBounds
+{
+    NSRect nominatorBounds = [self childLayoutAtIndex:0].bounds;
+    NSRect denominatorBounds = [self childLayoutAtIndex:1].bounds;
+    NSRect bounds;
+    bounds.origin.x = 0;
+    CGFloat y = CTFontGetAscent((CTFontRef)self.font) / 2 - kFractionFunctionLineWidth / 2;
+    y -= denominatorBounds.size.height;
+    bounds.size.width = MAX(nominatorBounds.size.width, denominatorBounds.size.width);
+    bounds.size.height = nominatorBounds.size.height + denominatorBounds.size.height + kFractionFunctionLineWidth;
+    return bounds;
+}
+
+- (void)draw
+{
+    CGFloat y = CTFontGetAscent((CTFontRef)self.font) / 2 - kFractionFunctionLineWidth / 2;
+    NSRectFill(NSMakeRect(0, y, self.bounds.size.width, kFractionFunctionLineWidth));
+}
+
+@end