add colorbox command (#121)

* add colorbox feature

* change pod version 1.5.3 -> 1.7.0

Author: ingun37

Podfile.lock

@@ -9,8 +9,8 @@ EXTERNAL SOURCES:
     :path: "./"
 
 SPEC CHECKSUMS:
-  iosMath: dfb93f207b01838413242bb5252b3eaf91558a12
+  iosMath: f7a6cbadf9d836d2149c2a84c435b1effc244cba
 
 PODFILE CHECKSUM: bade56080a0531a08830155fc215a0a5b44dd183
 
-COCOAPODS: 1.5.3
+COCOAPODS: 1.7.0

iosMath/lib/MTMathList.h

@@ -73,6 +73,7 @@ typedef NS_ENUM(NSUInteger, MTMathAtomType)
     /// Denotes style changes during rendering.
     kMTMathAtomStyle,
     kMTMathAtomColor,
+    kMTMathAtomColorbox,
 
     // Atoms after this point are not part of TeX and do not have the usual structure.
 
@@ -340,6 +341,23 @@ typedef NS_ENUM(unsigned int, MTLineStyle)  {
 
 @end
 
+/** An atom representing an colorbox element.
+ @note None of the usual fields of the `MTMathAtom` apply even though this
+ class inherits from `MTMathAtom`. i.e. it is meaningless to have a value
+ in the nucleus, subscript or superscript fields. */
+@interface MTMathColorbox : MTMathAtom
+
+/// Creates an empty color with a nil environment
+- (instancetype) init NS_DESIGNATED_INITIALIZER;
+
+/** The style represented by this object. */
+@property (nonatomic, nullable) NSString* colorString;
+
+/// The inner math list
+@property (nonatomic, nullable) MTMathList* innerList;
+
+@end
+
 /** An atom representing an table element. This atom is not like other
  atoms and is not present in TeX. We use it to represent the `\halign` command
  in TeX with some simplifications. This is used for matrices, equation

iosMath/lib/MTMathList.m

@@ -68,6 +68,8 @@ static BOOL isNotBinaryOperator(MTMathAtom* prevNode)
             return @"Style";
         case kMTMathAtomColor:
             return @"Color";
+        case kMTMathAtomColorbox:
+            return @"Colorbox";
         case kMTMathAtomTable:
             return @"Table";
     }
@@ -122,6 +124,9 @@ + (instancetype)atomWithType:(MTMathAtomType)type value:(NSString *)value
         case kMTMathAtomColor:
             return [[MTMathColor alloc] init];
 
+        case kMTMathAtomColorbox:
+            return [[MTMathColorbox alloc] init];
+            
         default:
             return [[MTMathAtom alloc] initWithType:type value:value];
     }
@@ -702,6 +707,52 @@ - (instancetype)finalized
 
 @end
 
+#pragma mark - MTMathColorbox
+
+@implementation MTMathColorbox
+
+
+- (instancetype)init
+{
+    self = [super initWithType:kMTMathAtomColorbox value:@""];
+    return self;
+}
+
+- (instancetype)initWithType:(MTMathAtomType)type value:(NSString *)value
+{
+    if (type == kMTMathAtomColorbox) {
+        return [self init];
+    }
+    @throw [NSException exceptionWithName:@"InvalidMethod"
+                                   reason:@"[MTMathColorbox initWithType:value:] cannot be called. Use [MTMathColorbox init] instead."
+                                 userInfo:nil];
+}
+
+- (NSString *)stringValue
+{
+    NSMutableString* str = [NSMutableString stringWithString:@"\\colorbox"];
+    [str appendFormat:@"{%@}{%@}", self.colorString, self.innerList.stringValue];
+    return str;
+}
+
+- (id)copyWithZone:(NSZone *)zone
+{
+    MTMathColorbox* op = [super copyWithZone:zone];
+    op.innerList = [self.innerList copyWithZone:zone];
+    op->_colorString = self.colorString;
+    return op;
+}
+
+- (instancetype)finalized
+{
+    MTMathColorbox *newInner = [super finalized];
+    newInner.innerList = newInner.innerList.finalized;
+    return newInner;
+}
+
+@end
+
+
 #pragma mark - MTMathTable
 
 @interface MTMathTable ()

iosMath/lib/MTMathListBuilder.m

@@ -500,6 +500,12 @@ - (MTMathAtom*) atomForCommand:(NSString*) command
         mathColor.colorString = [self readColor];
         mathColor.innerList = [self buildInternal:true];
         return mathColor;
+    } else if ([command isEqualToString:@"colorbox"]) {
+        // A color command has 2 arguments
+        MTMathColorbox* mathColorbox = [[MTMathColorbox alloc] init];
+        mathColorbox.colorString = [self readColor];
+        mathColorbox.innerList = [self buildInternal:true];
+        return mathColorbox;
     } else {
         NSString* errorMessage = [NSString stringWithFormat:@"Invalid command \\%@", command];
         [self setError:MTParseErrorInvalidCommand message:errorMessage];

iosMath/render/MTMathListDisplay.h

@@ -52,7 +52,8 @@ NS_ASSUME_NONNULL_BEGIN
 // The local color, if the color was mutated local with the color
 // command
 @property (nonatomic, nullable) MTColor *localTextColor;
-
+/// The background color for this display.
+@property (nonatomic, nullable) MTColor *localBackgroundColor;
 @end
 
 /// A rendering of a single CTLine as an MTDisplay

iosMath/render/MTMathListDisplay.m

@@ -45,6 +45,14 @@ @implementation MTDisplay
 
 - (void)draw:(CGContextRef)context
 {
+    if (self.localBackgroundColor != nil) {
+        CGContextSaveGState(context);
+        CGContextSetBlendMode(context, kCGBlendModeNormal);
+        CGContextSetFillColorWithColor(context, self.localBackgroundColor.CGColor);
+        CGContextFillRect(context, [self displayBounds]);
+        CGContextRestoreGState(context);
+    }
+    
 }
 
 - (CGRect) displayBounds
@@ -154,6 +162,7 @@ - (void)dealloc
 
 - (void)draw:(CGContextRef)context
 {
+    [super draw:context];
     CGContextSaveGState(context);
 
     CGContextSetTextPosition(context, self.position.x, self.position.y);
@@ -212,6 +221,7 @@ - (void)setTextColor:(MTColor *)textColor
 
 - (void)draw:(CGContextRef)context
 {
+    [super draw:context];
     CGContextSaveGState(context);
 
     // Make the current position the origin as all the positions of the sub atoms are relative to the origin.
@@ -324,6 +334,7 @@ - (void)setTextColor:(MTColor *)textColor
 
 - (void)draw:(CGContextRef)context
 {
+    [super draw:context];
     [_numerator draw:context];
     [_denominator draw:context];
 
@@ -416,6 +427,7 @@ - (void)setTextColor:(MTColor *)textColor
 
 - (void)draw:(CGContextRef)context
 {
+    [super draw:context];
     // draw the radicand & degree at its position
     [self.radicand draw:context];
     [self.degree draw:context];
@@ -474,6 +486,7 @@ - (instancetype)initWithGlpyh:(CGGlyph) glyph range:(NSRange) range font:(MTFont
 
 - (void)draw:(CGContextRef)context
 {
+    [super draw:context];
     CGContextSaveGState(context);
 
     [self.textColor setFill];
@@ -530,6 +543,7 @@ - (instancetype)initWithGlyphs:(NSArray<NSNumber *> *)glyphs offsets:(NSArray<NS
 
 - (void)draw:(CGContextRef)context
 {
+    [super draw:context];
     CGContextSaveGState(context);
 
     [self.textColor setFill];
@@ -671,6 +685,7 @@ - (void)setTextColor:(MTColor *)textColor
 
 - (void)draw:(CGContextRef)context
 {
+    [super draw:context];
     // Draw the elements.
     [self.upperLimit draw:context];
     [self.lowerLimit draw:context];
@@ -703,6 +718,7 @@ - (void)setTextColor:(MTColor *)textColor
 
 - (void)draw:(CGContextRef)context
 {
+    [super draw:context];
     [self.inner draw:context];
 
     CGContextSaveGState(context);
@@ -770,6 +786,7 @@ - (void) updateAccenteePosition
 
 - (void)draw:(CGContextRef)context
 {
+    [super draw:context];
     [self.accentee draw:context];
 
     CGContextSaveGState(context);

iosMath/render/internal/MTTypesetter.m

@@ -48,6 +48,7 @@ typedef NS_ENUM(int, MTInterElementSpaceType) {
 NSUInteger getInterElementSpaceArrayIndexForType(MTMathAtomType type, BOOL row) {
     switch (type) {
         case kMTMathAtomColor:
+        case kMTMathAtomColorbox:
         case kMTMathAtomOrdinary:
         case kMTMathAtomPlaceholder:   // A placeholder is treated as ordinary
             return 0;
@@ -629,6 +630,21 @@ - (void) createDisplayAtoms:(NSArray*) preprocessed
                 break;
             }
 
+            case kMTMathAtomColorbox: {
+                // stash the existing layout
+                if (_currentLine.length > 0) {
+                    [self addDisplayLine];
+                }
+                MTMathColorbox* colorboxAtom = (MTMathColorbox*) atom;
+                MTDisplay* display = [MTTypesetter createLineForMathList:colorboxAtom.innerList font:_font style:_style];
+                
+                display.localBackgroundColor = [MTColor colorFromHexString:colorboxAtom.colorString];
+                display.position = _currentPosition;
+                _currentPosition.x += display.width;
+                [_displayAtoms addObject:display];
+                break;
+            }
+                
             case kMTMathAtomRadical: {
                 // stash the existing layout
                 if (_currentLine.length > 0) {

iosMathExample/example/ViewController.m

@@ -82,7 +82,7 @@ - (void)viewDidLoad
     // set the size of the content view
     // Disable horizontal scrolling.
     [self setEqualWidths:contentView andView:self.scrollView];
-    [self setHeight:4280 forView:contentView];
+    [self setHeight:4350 forView:contentView];
 
 
     // Demo formulae
@@ -303,7 +303,7 @@ - (void)viewDidLoad
     self.labels[39] = [self createMathLabel:@"\\hat{\\frac12} \\; \\hat{\\sqrt 3}" withHeight:50];
 
     // large roots
-    self.labels[40] = [self createMathLabel:@"\\sqrt{1+\\sqrt{1+\\sqrt{1+\\sqrt{1+\\sqrt{1+\\cdots}}}}}" withHeight:80];
+    self.labels[40] = [self createMathLabel:@"\\colorbox{#f0f0e0}{\\sqrt{1+\\colorbox{#d0c0d0}{\\sqrt{1+\\colorbox{#a080c0}{\\sqrt{1+\\colorbox{#7050a0}{\\sqrt{1+\\colorbox{403060}{\\colorbox{#102000}{\\sqrt{1+\\cdots}}}}}}}}}}}" withHeight:80];
 
     self.labels[41] = [self createMathLabel:@"\\begin{bmatrix}"
                            "a & b\\\\ c & d \\\\ e & f \\\\ g &  h \\\\ i & j"
@@ -314,6 +314,12 @@ - (void)viewDidLoad
     self.labels[44] = [self createMathLabel:@"\\mathrm{using\\ mathrm}" withHeight:30];
     self.labels[45] = [self createMathLabel:@"\\text{using text}" withHeight:30];
     self.labels[46] = [self createMathLabel:@"\\text{Mary has }\\$500 + \\$200." withHeight:30];
+    
+    self.labels[47] = [self createMathLabel:@"\\colorbox{#888888}{\\begin{pmatrix}"
+                       "\\colorbox{#ff0000}{a} & \\colorbox{#00ff00}{b} \\\\"
+                       "\\colorbox{#00aaff}{c} & \\colorbox{#f0f0f0}{d}"
+                       "\\end{pmatrix}}"
+                                 withHeight:70];
 
     for (NSUInteger i = 1; i < self.labels.count; i++) {
         [self addLabelWithIndex:i inArray:self.labels toView:contentView];