Reorganized File Structure

Added Documentation

MathKit/MPSumFunctionLayout.m

@@ -0,0 +1,160 @@
+//
+//  MPSumFunctionLayout.m
+//  MathPad
+//
+//  Created by Kim Wittenburg on 23.04.14.
+//  Copyright (c) 2014 Kim Wittenburg. All rights reserved.
+//
+
+#import "MPSumFunctionLayout.h"
+
+#import "MPSumFunction.h"
+
+#import "NSIndexPath+MPAdditions.h"
+
+#define kSumFunctionStartExpressionOffset 0
+#define kSumFunctionTargetExpressionOffset 0
+#define kSumFunctionSumExpressionOffset 3
+#define kSumFunctionTrailingOffset 5
+
+@implementation MPSumFunctionLayout
+
+- (MPSumFunction *)sumFunction
+{
+    return (MPSumFunction *)self.function;
+}
+
+- (NSUInteger)indexOfLeadingChild
+{
+    return 2;
+}
+
+- (NSUInteger)indexOfTrailingChild
+{
+    return 2;
+}
+
+- (NSUInteger)indexOfChildAfterChildAtIndex:(NSUInteger)index
+{
+    if (index != 2) {
+        return 2;
+    }
+    return [super indexOfChildAfterChildAtIndex:index];
+}
+
+- (NSUInteger)indexOfChildBelowChildAtIndex:(NSUInteger)index
+{
+    return 0;
+}
+
+- (NSUInteger)indexOfChildAboveChildAtIndex:(NSUInteger)index
+{
+    return 1;
+}
+
+- (NSIndexSet *)indexesOfRemainingChildren
+{
+    return [NSIndexSet indexSetWithIndex:2];
+}
+
+- (CTLineRef)line
+{
+    CTLineRef line = [self lineForPrivateCacheIndex:0 generator:^CTLineRef{
+        return [self createLineForString:@"∑"
+                               usingFont:[NSFont fontWithName:@"Times New Roman"
+                                                         size:self.contextInferredFontSize]];
+    }];
+    return line;
+}
+
+- (NSRect)localLineBounds
+{
+    NSRect lineBounds = CTLineGetBoundsWithOptions(self.line, 0);
+    NSRect startExpressionBounds = [self childLayoutAtIndex:0].bounds;
+    NSRect targetExpressionBounds = [self childLayoutAtIndex:1].bounds;
+    CGFloat width = MAX(MAX(startExpressionBounds.size.width, targetExpressionBounds.size.width), lineBounds.size.width);
+    CGFloat xPosition = (width - lineBounds.size.width) / 2;
+    return NSMakeRect(xPosition, lineBounds.origin.y, lineBounds.size.width, lineBounds.size.height);
+}
+
+- (NSPoint)offsetOfChildLayoutAtIndex:(NSUInteger)index
+{
+    NSRect childBounds = [self childLayoutAtIndex:index].bounds;
+    NSRect localLineBounds = [self localLineBounds];
+    NSPoint offset;
+    if (index == 0) {
+        // Start Expression
+        offset.x = localLineBounds.origin.x + localLineBounds.size.width / 2 - childBounds.size.width / 2;
+        offset.y = localLineBounds.origin.y - kSumFunctionStartExpressionOffset - childBounds.size.height - childBounds.origin.y;
+    } else if (index == 1) {
+        // Target Expression
+        offset.x = localLineBounds.origin.x + localLineBounds.size.width / 2 - childBounds.size.width / 2;
+        offset.y = kSumFunctionTargetExpressionOffset + localLineBounds.size.height + localLineBounds.origin.y - childBounds.origin.y;
+    } else {
+        // Sum Expression
+        MPLayout *startExpressionLayout = [self childLayoutAtIndex:0];
+        MPLayout *targetExpressionLayout = [self childLayoutAtIndex:1];
+        CGFloat sumWidth = MAX(MAX(localLineBounds.origin.x + localLineBounds.size.width, startExpressionLayout.bounds.size.width), targetExpressionLayout.bounds.size.width);
+        offset.x = sumWidth + kSumFunctionSumExpressionOffset;
+        offset.y = 0;
+    }
+    return offset;
+}
+
+- (BOOL)childAtIndexUsesSmallSize:(NSUInteger)index
+{
+    return (index == 0 || index == 1) ? YES : self.usesSmallSize;
+}
+
+- (NSIndexPath *)indexPathForLocalMousePoint:(NSPoint)point
+{
+    if (point.x < CTLineGetBoundsWithOptions(self.line, 0).size.width / 2) {
+        return [NSIndexPath indexPathWithIndex:0];
+    } else {
+        return [NSIndexPath indexPathWithIndex:1];
+    }
+}
+
+- (NSRect)generateBounds
+{
+    NSRect lineBounds = CTLineGetBoundsWithOptions(self.line, 0);
+    NSRect startExpressionBounds = [self childLayoutAtIndex:0].bounds;
+    NSRect targetExpressionBounds = [self childLayoutAtIndex:1].bounds;
+    NSRect sumExpressionBounds = [self childLayoutAtIndex:2].bounds;
+    NSRect bounds = lineBounds;
+    
+    bounds.size.width = MAX(lineBounds.size.width, startExpressionBounds.size.width);
+    bounds.size.height += startExpressionBounds.size.height + kSumFunctionStartExpressionOffset;
+    bounds.origin.y -= startExpressionBounds.size.height + kSumFunctionStartExpressionOffset;
+
+    bounds.size.width = MAX(bounds.size.width, targetExpressionBounds.size.width);
+    bounds.size.height += targetExpressionBounds.size.height + kSumFunctionTargetExpressionOffset;
+    
+    bounds.size.width += kSumFunctionSumExpressionOffset + sumExpressionBounds.size.width + kSumFunctionTrailingOffset;
+    CGFloat yOffsetBottom = bounds.origin.y - sumExpressionBounds.origin.y;
+    CGFloat yOffsetTop = sumExpressionBounds.size.height - (yOffsetBottom + bounds.size.height);
+    bounds.size.height = MAX(yOffsetBottom, 0) + bounds.size.height + MAX(yOffsetTop, 0);
+    bounds.origin.y = MIN(sumExpressionBounds.origin.y, bounds.origin.y);
+    
+    return bounds;
+}
+
+- (void)draw
+{
+    // Get the current context
+    CGContextRef context = (CGContextRef)[[NSGraphicsContext currentContext] graphicsPort];
+        
+    // Set the text matrix
+    CGContextSetTextMatrix(context, CGAffineTransformIdentity);
+    
+    // Draw the sum symbol
+    CTLineRef line = [self line];
+    CFRetain(line);
+    NSRect localLineBounds = [self localLineBounds];
+    CGContextSetTextPosition(context, localLineBounds.origin.x, 0);
+    CTLineDraw(line, context);
+        
+    CFRelease(line);
+}
+
+@end