Reorganized File Structure

Added Documentation

MathKit/MPLayout.m

@@ -0,0 +1,206 @@
+//
+//  MPLayout.m
+//  MathPad
+//
+//  Created by Kim Wittenburg on 11.08.14.
+//  Copyright (c) 2014 Kim Wittenburg. All rights reserved.
+//
+
+#import "MPLayout.h"
+
+#import "MPRangePath.h"
+#import "NSIndexPath+MPAdditions.h"
+
+@interface MPLayout ()
+
+// Querying and Storing Caches
+- (BOOL)hasCacheForElementAtIndex:(NSUInteger)index;
+- (void)ensureCacheSizeForIndex:(NSUInteger)index;
+
+@end
+
+@implementation MPLayout {
+    NSMutableArray *_cache;
+    NSRect _cachedBounds;
+}
+
+#pragma mark Creation Methods
+- (id)init
+{
+    self = [super init];
+    if (self) {
+        _cache = [[NSMutableArray alloc] init];
+        _cachedBounds = NSZeroRect;
+    }
+    return self;
+}
+
+- (instancetype)initWithParent:(MPLayout *)parent
+{
+    self = [self init];
+    if (self) {
+        _parent = parent;
+    }
+    return self;
+}
+
+#pragma mark Properties
+- (NSFont *)normalFontWithSize:(CGFloat)size
+{
+    return [NSFont fontWithName:@"CMU Serif"
+                           size:size];
+}
+
+- (NSFont *)specialFontWithSize:(CGFloat)size
+{
+    return [NSFont fontWithName:@"CMU Serif Italic"
+                           size:size];
+}
+
+- (CGFloat)contextInferredFontSize
+{
+    return self.usesSmallSize ? self.smallFontSize : self.normalFontSize;
+}
+
+- (CGFloat)normalFontSize
+{
+    return 18.0;
+}
+
+- (CGFloat)smallFontSize
+{
+    return 12.0;
+}
+
+- (NSFont *)font
+{
+    return [self normalFontWithSize:self.contextInferredFontSize];
+}
+
+#pragma mark Cache Tree
+// Querying and Storing Caches
+- (BOOL)hasCacheForElementAtIndex:(NSUInteger)index
+{
+    if (index >= _cache.count) {
+        return NO;
+    }
+    return _cache[index] != [NSNull null];
+}
+
+- (id)cachableObjectForIndex:(NSUInteger)index
+                   generator:(id (^)())generator
+{
+    if ([self hasCacheForElementAtIndex:index]) {
+        return _cache[index];
+    }
+    id object = generator();
+    [self ensureCacheSizeForIndex:index];
+    _cache[index] = object;
+    return object;
+}
+
+- (void)ensureCacheSizeForIndex:(NSUInteger)index
+{
+    while (index >= _cache.count) {
+        [_cache addObject:[NSNull null]];
+    }
+}
+
+// Clearing Caches
+- (void)clearCacheInRange:(NSRange)range
+        replacementLength:(NSUInteger)replacementLength
+{
+    NSMutableArray *placeholders = [[NSMutableArray alloc] initWithCapacity:replacementLength];
+    while (placeholders.count < replacementLength) {
+        [placeholders addObject:[NSNull null]];
+    }
+    [_cache replaceObjectsInRange:range
+             withObjectsFromArray:placeholders];
+    [self invalidate];
+}
+
+- (void)invalidate
+{
+    _cachedBounds = NSZeroRect;
+    [self.parent invalidate];
+}
+
+- (MPLayout *)childLayoutAtIndexPath:(NSIndexPath *)indexPath
+{
+    if (indexPath.length == 0) {
+        return self;
+    }
+    MPLayout *child = [self childLayoutAtIndex:indexPath.firstIndex];
+    return [child childLayoutAtIndexPath:[indexPath indexPathByRemovingFirstIndex]];
+}
+
+#pragma mark Calculation and Drawing Methods
+- (CTLineRef)createLineForString:(NSString *)aString
+{
+    return [self createLineForString:aString
+                           usingFont:self.font];
+}
+
+- (CTLineRef)createLineForString:(NSString *)aString emphasize:(BOOL)emphasize
+{
+    return [self createLineForString:aString
+                           usingFont:[NSFont systemFontOfSize:[NSFont systemFontSize]]];
+}
+
+- (CTLineRef)createLineForString:(NSString *)aString
+                       usingFont:(NSFont *)font
+{
+    NSAttributedString *text = [[NSAttributedString alloc] initWithString:aString
+                                                               attributes:@{NSFontAttributeName: font}];
+    CFAttributedStringRef attributedString = CFBridgingRetain(text);
+    CTLineRef line = CTLineCreateWithAttributedString(attributedString);
+    CFRelease(attributedString);
+    return line;
+}
+
+- (NSRect)bounds
+{
+    if (NSEqualRects(_cachedBounds, NSZeroRect)) {
+        _cachedBounds = [self generateBounds];
+    }
+    return _cachedBounds;
+}
+
+- (NSRect)boundingRectForRangePath:(MPRangePath *)rangePath
+{
+    if (rangePath.location.length == 1) {
+        return [self boundingRectForRange:rangePath.rangeAtLastIndex];
+    }
+    NSUInteger nextIndex = [rangePath.location indexAtPosition:0];
+    NSIndexPath *newLocation = [rangePath.location indexPathByRemovingFirstIndex];
+    MPRangePath *newRangePath = [[MPRangePath alloc] initWithLocation:newLocation length:rangePath.length];
+    NSRect bounds = [[self childLayoutAtIndex:nextIndex] boundingRectForRangePath:newRangePath];
+    NSPoint offset = [self offsetOfChildLayoutAtIndex:nextIndex];
+    bounds.origin = NSMakePoint(bounds.origin.x + offset.x, bounds.origin.y + offset.y);
+    return bounds;
+}
+
+- (BOOL)drawsChildrenManually
+{
+    return NO;
+}
+
+- (void)drawAtPoint:(NSPoint)point
+{
+    NSAffineTransform *transform = [NSAffineTransform transform];
+    [transform translateXBy:point.x
+                        yBy:point.y];
+    [transform concat];
+    [self draw];
+    if (!self.drawsChildrenManually) {
+        for (NSUInteger index = 0; index < [self numberOfChildren]; index++) {
+            MPLayout *childLayout = [self childLayoutAtIndex:index];
+            NSPoint offset = [self offsetOfChildLayoutAtIndex:index];
+            [childLayout drawAtPoint:offset];
+        }
+    }
+    [transform invert];
+    [transform concat];
+}
+
+@end