Added MPExpressionLayout, MPFunctionLayout and MPExpressionStorage as Rendering System for Expressions

MathPad/MPFunctionLayout.m

@@ -0,0 +1,121 @@
+//
+//  MPFunctionLayout.m
+//  MathPad
+//
+//  Created by Kim Wittenburg on 22.04.14.
+//  Copyright (c) 2014 Kim Wittenburg. All rights reserved.
+//
+
+#import "MPFunctionLayout.h"
+#import "MPExpressionLayout.h"
+#import "MPExpressionStorage.h"
+#import "MPFunction.h"
+
+#import "MPSumFunction.h"
+#import "MPSumFunctionLayout.h"
+
+@implementation MPFunctionLayout
+
+#pragma mark Creation Methods
+
++ (instancetype)functionLayoutForFunctionAtIndexPath:(NSIndexPath *)functionPath
+                                              parent:(MPExpressionLayout *)parent
+{
+    MPFunction *function = [parent.expressionStorage symbolAtIndexPath:functionPath];
+    Class class = [function class];
+    if (class == [MPSumFunction class]) {
+        return [[MPSumFunctionLayout alloc] initWithFunctionPath:functionPath parent:parent];
+    }
+    return nil;
+}
+
+- (id)initWithFunctionPath:(NSIndexPath *)functionPath
+                    parent:(MPExpressionLayout *)parent
+{
+    self = [super init];
+    if (self) {
+        _functionPath = functionPath;
+        _parent = parent;
+        _childCache = [[NSMutableArray alloc] init];
+    }
+    return self;
+}
+
+#pragma mark Properties
+
+- (MPExpressionStorage *)expressionStorage
+{
+    return self.parent.expressionStorage;
+}
+
+- (MPFunction *)function
+{
+    return [self.expressionStorage symbolAtIndexPath:self.functionPath];
+}
+
+- (NSLayoutManager *)layoutManager
+{
+    return self.expressionStorage.layoutManager;
+}
+
+- (NSTextContainer *)textContainer
+{
+    return self.expressionStorage.textContainer;
+}
+
+- (NSTextStorage *)textStorage
+{
+    return self.expressionStorage.textStorage;
+}
+
+#pragma mark Cache Methods
+
+- (void)invalidate
+{
+    _valid = NO;
+}
+
+- (BOOL)hasCacheForChildAtIndex:(NSUInteger)index
+{
+    if (index >= _childCache.count) {
+        return NO;
+    }
+    return _childCache[index] != [NSNull null];
+}
+
+- (MPExpressionLayout *)expressionLayoutForChildAtIndex:(NSUInteger)index
+{
+    if ([self hasCacheForChildAtIndex:index]) {
+        return _childCache[index];
+    }
+    while (index >= _childCache.count) {
+        [_childCache addObject:[NSNull null]];
+    }
+    MPExpressionLayout *expressionLayout = [[MPExpressionLayout alloc] initWithExpressionPath:[self.functionPath indexPathByAddingIndex:index] parent:self];
+    _childCache[index] = expressionLayout;
+    return expressionLayout;
+}
+
+#pragma mark Size Calculation Methods
+
+- (NSSize)sizeOfFunction
+{
+    if (!_valid) {
+        _cachedSize = [self calculateSize];
+        _valid = YES;
+    }
+    return _cachedSize;
+}
+
+- (NSSize)calculateSize
+{
+    return NSMakeSize(0, 0);
+}
+
+#pragma mark Drawing Methods
+
+- (void)drawFunctionAtPoint:(NSPoint)point
+{
+}
+
+@end