Iphone 现有圆上的曲线文本
对于我正在构建的应用程序，我画了两个圆。一个比另一个大一点。我想在这些线之间弯曲文本，以创建一个圆形菜单 我读过很多关于弯曲文本的东西，你必须将文本分割成几个字符，并在脑海中以正确的角度（通过旋转你正在绘制的上下文）绘制每个字符 我就是不知道如何为我的角色找到合适的角度和位置 我在菜单上加了一个截图，显示了菜单目前的样子。只有我添加的文本是从UIImageView中的图像加载的 我希望有人能给我一些起点，让我在某些点上画出白色圆圈中的文字 编辑： 好的，我现在在这一点上： 我通过使用以下代码来完成：Iphone 现有圆上的曲线文本,iphone,cocoa-touch,math,quartz-graphics,quartz-2d,Iphone,Cocoa Touch,Math,Quartz Graphics,Quartz 2d,对于我正在构建的应用程序，我画了两个圆。一个比另一个大一点。我想在这些线之间弯曲文本，以创建一个圆形菜单 我读过很多关于弯曲文本的东西，你必须将文本分割成几个字符，并在脑海中以正确的角度（通过旋转你正在绘制的上下文）绘制每个字符 我就是不知道如何为我的角色找到合适的角度和位置 我在菜单上加了一个截图，显示了菜单目前的样子。只有我添加的文本是从UIImageView中的图像加载的 我希望有人能给我一些起点，让我在某些点上画出白色圆圈中的文字 编辑： 好的，我现在在这一点上： 我通过使用以下代码
- (UIImage*) createMenuRingWithFrame:(CGRect)frame
{
CGRect imageSize = CGRectMake(0,0,300,300);
float perSectionDegrees = 360 / [sections count];
float totalRotation = 90;
char* fontName = (char*)[self.menuItemsFont.fontName cStringUsingEncoding:NSASCIIStringEncoding];
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
CGContextRef context = CGBitmapContextCreate(NULL, imageSize.size.width, imageSize.size.height, 8, 4 * imageSize.size.width, colorSpace, kCGImageAlphaPremultipliedFirst);
CGContextSetTextMatrix(context, CGAffineTransformIdentity);
CGContextSelectFont(context, fontName, 18, kCGEncodingMacRoman);
CGContextSetRGBFillColor(context, 0, 0, 0, 1);
CGPoint centerPoint = CGPointMake(imageSize.size.width / 2, imageSize.size.height / 2);
double radius = (frame.size.width / 2);
CGContextStrokeEllipseInRect(context, CGRectMake(centerPoint.x - (frame.size.width / 2), centerPoint.y - (frame.size.height / 2), frame.size.width, frame.size.height));
for (int index = 0; index < [sections count]; index++)
{
NSString* menuItemText = [sections objectAtIndex:index];
CGSize textSize = [menuItemText sizeWithFont:self.menuItemsFont];
char* menuItemTextChar = (char*)[menuItemText cStringUsingEncoding:NSASCIIStringEncoding];
float x = centerPoint.x + radius * cos(degreesToRadians(totalRotation));
float y = centerPoint.y + radius * sin(degreesToRadians(totalRotation));
CGContextSaveGState(context);
CGContextTranslateCTM(context, x, y);
CGContextRotateCTM(context, degreesToRadians(totalRotation - 90));
CGContextShowTextAtPoint(context, 0 - (textSize.width / 2), 0 - (textSize.height / 2), menuItemTextChar, strlen(menuItemTextChar));
CGContextRestoreGState(context);
totalRotation += perSectionDegrees;
}
CGImageRef contextImage = CGBitmapContextCreateImage(context);
CGContextRelease(context);
CGColorSpaceRelease(colorSpace);
return [UIImage imageWithCGImage:contextImage];
}
- (void) drawStringAtContext:(CGContextRef) context string:(NSString*) text atAngle:(float) angle withRadius:(float) radius
{
CGSize textSize = [text sizeWithFont:self.menuItemsFont];
float perimeter = 2 * M_PI * radius;
float textAngle = textSize.width / perimeter * 2 * M_PI;
angle += textAngle / 2;
for (int index = 0; index < [text length]; index++)
{
NSRange range = {index, 1};
NSString* letter = [text substringWithRange:range];
char* c = (char*)[letter cStringUsingEncoding:NSASCIIStringEncoding];
CGSize charSize = [letter sizeWithFont:self.menuItemsFont];
NSLog(@"Char %@ with size: %f x %f", letter, charSize.width, charSize.height);
float x = radius * cos(angle);
float y = radius * sin(angle);
float letterAngle = (charSize.width / perimeter * -2 * M_PI);
CGContextSaveGState(context);
CGContextTranslateCTM(context, x, y);
CGContextRotateCTM(context, (angle - 0.5 * M_PI));
CGContextShowTextAtPoint(context, 0, 0, c, strlen(c));
CGContextRestoreGState(context);
angle += letterAngle;
}
}
- (UIImage*) createMenuRingWithFrame:(CGRect)frame
{
CGPoint centerPoint = CGPointMake(frame.size.width / 2, frame.size.height / 2);
char* fontName = (char*)[self.menuItemsFont.fontName cStringUsingEncoding:NSASCIIStringEncoding];
CGFloat* ringColorComponents = (float*)CGColorGetComponents(ringColor.CGColor);
CGFloat* textColorComponents = (float*)CGColorGetComponents(textColor.CGColor);
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
CGContextRef context = CGBitmapContextCreate(NULL, frame.size.width, frame.size.height, 8, 4 * frame.size.width, colorSpace, kCGImageAlphaPremultipliedFirst);
CGContextSetTextMatrix(context, CGAffineTransformIdentity);
CGContextSelectFont(context, fontName, 18, kCGEncodingMacRoman);
CGContextSetRGBStrokeColor(context, ringColorComponents[0], ringColorComponents[1], ringColorComponents[2], ringAlpha);
CGContextSetLineWidth(context, ringWidth);
CGContextStrokeEllipseInRect(context, CGRectMake(ringWidth, ringWidth, frame.size.width - (ringWidth * 2), frame.size.height - (ringWidth * 2)));
CGContextSetRGBFillColor(context, textColorComponents[0], textColorComponents[1], textColorComponents[2], textAlpha);
CGContextSaveGState(context);
CGContextTranslateCTM(context, centerPoint.x, centerPoint.y);
float angleStep = 2 * M_PI / [sections count];
float angle = degreesToRadians(90);
textRadius = textRadius - 12;
for (NSString* text in sections)
{
[self drawStringAtContext:context string:text atAngle:angle withRadius:textRadius];
angle -= angleStep;
}
CGContextRestoreGState(context);
CGImageRef contextImage = CGBitmapContextCreateImage(context);
CGContextRelease(context);
CGColorSpaceRelease(colorSpace);
[self saveImage:[UIImage imageWithCGImage:contextImage] withName:@"test.png"];
return [UIImage imageWithCGImage:contextImage];
}
-（void）drawStringAtContext:（CGContextRef）context string:（NSString*）文本角：（float）带半径的角度：（float）半径
{
CGSize textSize=[text-sizeWithFont:self.menuItemsFont]；
浮动周长=2*M_PI*半径；
浮动textAngle=textSize.width/周长*2*M_PI；
角度+=文本角度/2；
对于（int index=0；索引<[文本长度]；索引++）
{
NSRange range={index，1}；
NSString*字母=[text substringWithRange:range]；
char*c=（char*）[字母cStringUsingEncoding:NSASCIIStringEncoding]；
CGSize charSize=[letter sizeWithFont:self.menuItemsFont]；
NSLog（@“Char%@大小为：%f x%f”，字母，charSize.width，charSize.height）；
浮动x=半径*cos（角度）；
浮动y=半径*sin（角度）；
浮动字体角度=（字符大小、宽度/周长*-2*M_-PI）；
CGContextSaveGState（上下文）；
cgcontexttranslatecm（上下文，x，y）；
CGContextRotateCTM（上下文，（角度-0.5*M_-PI））；
CGContextShowTextAtPoint（上下文，0，0，c，strlen（c））；
CGContextRestoreGState（上下文）；
角度+=字母角度；
}
}
-（UIImage*）createMenuRingWithFrame:（CGRect）帧
{
CGPoint centerPoint=CGPointMake（frame.size.width/2，frame.size.height/2）；
char*fontName=（char*）[self.menuItemsFont.fontName cStringUsingEncoding:NSASCIIStringEncoding]；
CGFloat*ringColorComponents=（float*）CGColorGetComponents（ringColor.CGColor）；
CGFloat*textColorComponents=（float*）CGColorGetComponents（textColor.CGColor）；
CGColorSpaceRef colorSpace=CGColorSpaceCreateDeviceRGB（）；
CGContextRef context=CGBitmapContextCreate（NULL，frame.size.width，frame.size.height，8,4*frame.size.width，colorSpace，KCGIMAGEAlphaPremultipledFirst）；
CGContextSetTextMatrix（上下文，CGAffineTransformity）；
CGContextSelectFont（上下文，fontName，18，kCGEncodingMacRoman）；
CGContextSetRGBStrokeColor（上下文，ringColorComponents[0]，ringColorComponents[1]，ringColorComponents[2]，ringAlpha）；
CGContextSetLineWidth（上下文，环宽）；
CGContextStrokeEllipseInRect（上下文，CGRectMake（环宽，环宽，frame.size.width-（环宽*2），frame.size.height-（环宽*2））；
CGContextSetRGBFillColor（上下文，textColorComponents[0]，textColorComponents[1]，textColorComponents[2]，textAlpha）；
CGContextSaveGState（上下文）；
CGContextTranslateCm（上下文，centerPoint.x，centerPoint.y）；
浮动角度步长=2*M_PI/[截面计数]；
浮动角度=度弧度（90）；
textRadius=textRadius-12；
用于（NSString*节中的文本）
{
[self-drawStringAtContext:context string:text atAngle:angle with Radius:textRadius]；
角度-=角度步长；
}
CGContextRestoreGState（上下文）；
CGImageRef contextImage=CGBitmapContextCreateImage（上下文）；
CGContextRelease（上下文）；
CGCOLORSPACTERELEASE（色彩空间）；
[自我保存图像：[UIImage imageWithCGImage:contextImage]名称：@“test.png”]；
返回[UIImage imageWithCGImage:contextImage]；
}
CoreText也可以在iOS中使用，因此您应该能够实现类似的功能。我试图在纸上快速计算出来，所以我可能错了：） 将字符串的长度转换为屏幕上的单位。因此（字符串长度/圆周长）*2Pi。现在，整个字符串的角度以弧度为单位。（即字符串起点和终点之间的角度） 对于单独的字母，您可以使用相同的方法获得单个字母的角度（弧度）（使用字母宽度） 一旦你有了弧度的角度，你就可以计算出字母的x和y位置（以及旋转） 奖励：对于均匀间距，您甚至可以计算出所有字符串的总长度与整个周长之间的比率。并在字符串之间等分剩余的空间 更新 我使用html5/canvas制作了一个浏览器，所以用一个像样的浏览器来查看：）你应该能够移植它。（请注意，代码没有注释）
wtf：当chrome调试控制台打开时，代码运行正常，当它关闭时失败。（解决方法：打开chrome控制台：ctrl-shift-j并重新加载页面：f5）；FF3.6.8看起来不错，但字母“跳舞”。取内圈的周长。这是要渲染角色底部的圆。我们称之为周长
totalLength- (void) drawStringAtContext:(CGContextRef) context string:(NSString*) text atAngle:(float) angle withRadius:(float) radius
{
CGSize textSize = [text sizeWithFont:self.menuItemsFont];
float perimeter = 2 * M_PI * radius;
float textAngle = textSize.width / perimeter * 2 * M_PI;
angle += textAngle / 2;
for (int index = 0; index < [text length]; index++)
{
NSRange range = {index, 1};
NSString* letter = [text substringWithRange:range];
char* c = (char*)[letter cStringUsingEncoding:NSASCIIStringEncoding];
CGSize charSize = [letter sizeWithFont:self.menuItemsFont];
NSLog(@"Char %@ with size: %f x %f", letter, charSize.width, charSize.height);
float x = radius * cos(angle);
float y = radius * sin(angle);
float letterAngle = (charSize.width / perimeter * -2 * M_PI);
CGContextSaveGState(context);
CGContextTranslateCTM(context, x, y);
CGContextRotateCTM(context, (angle - 0.5 * M_PI));
CGContextShowTextAtPoint(context, 0, 0, c, strlen(c));
CGContextRestoreGState(context);
angle += letterAngle;
}
}
- (UIImage*) createMenuRingWithFrame:(CGRect)frame
{
CGPoint centerPoint = CGPointMake(frame.size.width / 2, frame.size.height / 2);
char* fontName = (char*)[self.menuItemsFont.fontName cStringUsingEncoding:NSASCIIStringEncoding];
CGFloat* ringColorComponents = (float*)CGColorGetComponents(ringColor.CGColor);
CGFloat* textColorComponents = (float*)CGColorGetComponents(textColor.CGColor);
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
CGContextRef context = CGBitmapContextCreate(NULL, frame.size.width, frame.size.height, 8, 4 * frame.size.width, colorSpace, kCGImageAlphaPremultipliedFirst);
CGContextSetTextMatrix(context, CGAffineTransformIdentity);
CGContextSelectFont(context, fontName, 18, kCGEncodingMacRoman);
CGContextSetRGBStrokeColor(context, ringColorComponents[0], ringColorComponents[1], ringColorComponents[2], ringAlpha);
CGContextSetLineWidth(context, ringWidth);
CGContextStrokeEllipseInRect(context, CGRectMake(ringWidth, ringWidth, frame.size.width - (ringWidth * 2), frame.size.height - (ringWidth * 2)));
CGContextSetRGBFillColor(context, textColorComponents[0], textColorComponents[1], textColorComponents[2], textAlpha);
CGContextSaveGState(context);
CGContextTranslateCTM(context, centerPoint.x, centerPoint.y);
float angleStep = 2 * M_PI / [sections count];
float angle = degreesToRadians(90);
textRadius = textRadius - 12;
for (NSString* text in sections)
{
[self drawStringAtContext:context string:text atAngle:angle withRadius:textRadius];
angle -= angleStep;
}
CGContextRestoreGState(context);
CGImageRef contextImage = CGBitmapContextCreateImage(context);
CGContextRelease(context);
CGColorSpaceRelease(colorSpace);
[self saveImage:[UIImage imageWithCGImage:contextImage] withName:@"test.png"];
return [UIImage imageWithCGImage:contextImage];
}
block = max(textWidths)
assert(block * len(textWidths) <= totalLength)
offsets = [(block * i) + ((block-width) / 2) for i, width in enumerate(textWidths)]
def offsetToAngle(pixel):
ratio = pixel / totalLength
angle = math.pi * 2 * ratio # cool kids use radians.
return angle
def angleToPosition(angle, characterWidth):
xNorm = math.sin(angle + circleRotation)
yNorm = math.cos(angle + circleRotation)
halfCWidth = characterWidth / 2
x = xNorm * radius + yNorm * halfCWidth # +y = tangent
y = yNorm * radius - xNorm * halfCWidth # -x = tangent again.
# translate to the circle centre
x += circleCentre.x
y += circleCentre.y
return x,y
for text, offset in zip(textItems, offsets):
pix = offset # start each block at the offset we calculated earlier.
for c in text:
cWidth = measureGlyph(c)
# choose the circumference location of the middle of the character
# this is to match with the tangent calculation of tangentToOffset
angle = offsetToAngle(pix + cWidth / 2)
x,y = angleToPosition(angle, cWidth)
drawGlyph(c, x, y, angle)
pix += cWidth # start of next character in circumference space
/*
File: CoreTextArcView.m (iOS version)
Abstract: Defines and implements the CoreTextArcView custom UIView subclass to
draw text on a curve and illustrate best practices with CoreText.
Based on CoreTextArcView provided by Apple for Mac OS X https://developer.apple.com/library/mac/#samplecode/CoreTextArcCocoa/Introduction/Intro.html
Ported to iOS (& added color, arcsize features) August 2011 by Alec Vance, Juggleware LLC http://juggleware.com/
*/
#import <UIKit/UIKit.h>
#import <CoreText/CoreText.h>
@interface CoreTextArcView : UIView {
@private
UIFont * _font;
NSString * _string;
CGFloat _radius;
UIColor * _color;
CGFloat _arcSize;
CGFloat _shiftH, _shiftV; // horiz & vertical shift
struct {
unsigned int showsGlyphBounds:1;
unsigned int showsLineMetrics:1;
unsigned int dimsSubstitutedGlyphs:1;
unsigned int reserved:29;
} _flags;
}
@property(retain, nonatomic) UIFont *font;
@property(retain, nonatomic) NSString *text;
@property(readonly, nonatomic) NSAttributedString *attributedString;
@property(assign, nonatomic) CGFloat radius;
@property(nonatomic) BOOL showsGlyphBounds;
@property(nonatomic) BOOL showsLineMetrics;
@property(nonatomic) BOOL dimsSubstitutedGlyphs;
@property(retain, nonatomic) UIColor *color;
@property(nonatomic) CGFloat arcSize;
@property(nonatomic) CGFloat shiftH, shiftV;
@end
/*
File: CoreTextArcView.m (iOS version)
*/
#import "CoreTextArcView.h"
#import <AssertMacros.h>
#import <QuartzCore/QuartzCore.h>
#define ARCVIEW_DEBUG_MODE NO
#define ARCVIEW_DEFAULT_FONT_NAME @"Helvetica"
#define ARCVIEW_DEFAULT_FONT_SIZE 64.0
#define ARCVIEW_DEFAULT_RADIUS 150.0
#define ARCVIEW_DEFAULT_ARC_SIZE 180.0
@implementation CoreTextArcView
- (id)initWithFrame:(CGRect)frame {
self = [super initWithFrame:frame];
if (self) {
self.font = [UIFont fontWithName:ARCVIEW_DEFAULT_FONT_NAME size:ARCVIEW_DEFAULT_FONT_SIZE];
self.text = @"Curvaceous Type";
self.radius = ARCVIEW_DEFAULT_RADIUS;
self.showsGlyphBounds = NO;
self.showsLineMetrics = NO;
self.dimsSubstitutedGlyphs = NO;
self.color = [UIColor whiteColor];
self.arcSize = ARCVIEW_DEFAULT_ARC_SIZE;
self.shiftH = self.shiftV = 0.0f;
}
return self;
}
typedef struct GlyphArcInfo {
CGFloat width;
CGFloat angle; // in radians
} GlyphArcInfo;
static void PrepareGlyphArcInfo(CTLineRef line, CFIndex glyphCount, GlyphArcInfo *glyphArcInfo, CGFloat arcSizeRad)
{
NSArray *runArray = (NSArray *)CTLineGetGlyphRuns(line);
// Examine each run in the line, updating glyphOffset to track how far along the run is in terms of glyphCount.
CFIndex glyphOffset = 0;
for (id run in runArray) {
CFIndex runGlyphCount = CTRunGetGlyphCount((CTRunRef)run);
// Ask for the width of each glyph in turn.
CFIndex runGlyphIndex = 0;
for (; runGlyphIndex < runGlyphCount; runGlyphIndex++) {
glyphArcInfo[runGlyphIndex + glyphOffset].width = CTRunGetTypographicBounds((CTRunRef)run, CFRangeMake(runGlyphIndex, 1), NULL, NULL, NULL);
}
glyphOffset += runGlyphCount;
}
double lineLength = CTLineGetTypographicBounds(line, NULL, NULL, NULL);
CGFloat prevHalfWidth = glyphArcInfo[0].width / 2.0;
glyphArcInfo[0].angle = (prevHalfWidth / lineLength) * arcSizeRad;
// Divide the arc into slices such that each one covers the distance from one glyph's center to the next.
CFIndex lineGlyphIndex = 1;
for (; lineGlyphIndex < glyphCount; lineGlyphIndex++) {
CGFloat halfWidth = glyphArcInfo[lineGlyphIndex].width / 2.0;
CGFloat prevCenterToCenter = prevHalfWidth + halfWidth;
glyphArcInfo[lineGlyphIndex].angle = (prevCenterToCenter / lineLength) * arcSizeRad;
prevHalfWidth = halfWidth;
}
}
// ensure that redraw occurs.
-(void)setText:(NSString *)text{
[_string release];
_string = [text retain];
[self setNeedsDisplay];
}
//set arc size in degrees (180 = half circle)
-(void)setArcSize:(CGFloat)degrees{
_arcSize = degrees * M_PI/180.0;
}
//get arc size in degrees
-(CGFloat)arcSize{
return _arcSize * 180.0/M_PI;
}
- (void)drawRect:(CGRect)rect {
// Don't draw if we don't have a font or string
if (self.font == NULL || self.text == NULL)
return;
// Initialize the text matrix to a known value
CGContextRef context = UIGraphicsGetCurrentContext();
//Reset the transformation
//Doing this means you have to reset the contentScaleFactor to 1.0
CGAffineTransform t0 = CGContextGetCTM(context);
CGFloat xScaleFactor = t0.a > 0 ? t0.a : -t0.a;
CGFloat yScaleFactor = t0.d > 0 ? t0.d : -t0.d;
t0 = CGAffineTransformInvert(t0);
if (xScaleFactor != 1.0 || yScaleFactor != 1.0)
t0 = CGAffineTransformScale(t0, xScaleFactor, yScaleFactor);
CGContextConcatCTM(context, t0);
CGContextSetTextMatrix(context, CGAffineTransformIdentity);
if(ARCVIEW_DEBUG_MODE){
// Draw a black background (debug)
CGContextSetFillColorWithColor(context, [UIColor blackColor].CGColor);
CGContextFillRect(context, self.layer.bounds);
}
NSAttributedString *attStr = self.attributedString;
CFAttributedStringRef asr = (CFAttributedStringRef)attStr;
CTLineRef line = CTLineCreateWithAttributedString(asr);
assert(line != NULL);
CFIndex glyphCount = CTLineGetGlyphCount(line);
if (glyphCount == 0) {
CFRelease(line);
return;
}
GlyphArcInfo * glyphArcInfo = (GlyphArcInfo*)calloc(glyphCount, sizeof(GlyphArcInfo));
PrepareGlyphArcInfo(line, glyphCount, glyphArcInfo, _arcSize);
// Move the origin from the lower left of the view nearer to its center.
CGContextSaveGState(context);
CGContextTranslateCTM(context, CGRectGetMidX(rect)+_shiftH, CGRectGetMidY(rect)+_shiftV - self.radius / 2.0);
if(ARCVIEW_DEBUG_MODE){
// Stroke the arc in red for verification.
CGContextBeginPath(context);
CGContextAddArc(context, 0.0, 0.0, self.radius, M_PI_2+_arcSize/2.0, M_PI_2-_arcSize/2.0, 1);
CGContextSetRGBStrokeColor(context, 1.0, 0.0, 0.0, 1.0);
CGContextStrokePath(context);
}
// Rotate the context 90 degrees counterclockwise (per 180 degrees)
CGContextRotateCTM(context, _arcSize/2.0);
// Now for the actual drawing. The angle offset for each glyph relative to the previous glyph has already been calculated; with that information in hand, draw those glyphs overstruck and centered over one another, making sure to rotate the context after each glyph so the glyphs are spread along a semicircular path.
CGPoint textPosition = CGPointMake(0.0, self.radius);
CGContextSetTextPosition(context, textPosition.x, textPosition.y);
CFArrayRef runArray = CTLineGetGlyphRuns(line);
CFIndex runCount = CFArrayGetCount(runArray);
CFIndex glyphOffset = 0;
CFIndex runIndex = 0;
for (; runIndex < runCount; runIndex++) {
CTRunRef run = (CTRunRef)CFArrayGetValueAtIndex(runArray, runIndex);
CFIndex runGlyphCount = CTRunGetGlyphCount(run);
Boolean drawSubstitutedGlyphsManually = false;
CTFontRef runFont = CFDictionaryGetValue(CTRunGetAttributes(run), kCTFontAttributeName);
// Determine if we need to draw substituted glyphs manually. Do so if the runFont is not the same as the overall font.
if (self.dimsSubstitutedGlyphs && ![self.font isEqual:(UIFont *)runFont]) {
drawSubstitutedGlyphsManually = true;
}
CFIndex runGlyphIndex = 0;
for (; runGlyphIndex < runGlyphCount; runGlyphIndex++) {
CFRange glyphRange = CFRangeMake(runGlyphIndex, 1);
CGContextRotateCTM(context, -(glyphArcInfo[runGlyphIndex + glyphOffset].angle));
// Center this glyph by moving left by half its width.
CGFloat glyphWidth = glyphArcInfo[runGlyphIndex + glyphOffset].width;
CGFloat halfGlyphWidth = glyphWidth / 2.0;
CGPoint positionForThisGlyph = CGPointMake(textPosition.x - halfGlyphWidth, textPosition.y);
// Glyphs are positioned relative to the text position for the line, so offset text position leftwards by this glyph's width in preparation for the next glyph.
textPosition.x -= glyphWidth;
CGAffineTransform textMatrix = CTRunGetTextMatrix(run);
textMatrix.tx = positionForThisGlyph.x;
textMatrix.ty = positionForThisGlyph.y;
CGContextSetTextMatrix(context, textMatrix);
if (!drawSubstitutedGlyphsManually) {
CTRunDraw(run, context, glyphRange);
}
else {
// We need to draw the glyphs manually in this case because we are effectively applying a graphics operation by setting the context fill color. Normally we would use kCTForegroundColorAttributeName, but this does not apply as we don't know the ranges for the colors in advance, and we wanted demonstrate how to manually draw.
CGFontRef cgFont = CTFontCopyGraphicsFont(runFont, NULL);
CGGlyph glyph;
CGPoint position;
CTRunGetGlyphs(run, glyphRange, &glyph);
CTRunGetPositions(run, glyphRange, &position);
CGContextSetFont(context, cgFont);
CGContextSetFontSize(context, CTFontGetSize(runFont));
CGContextSetRGBFillColor(context, 0.25, 0.25, 0.25, 0.5);
CGContextShowGlyphsAtPositions(context, &glyph, &position, 1);
CFRelease(cgFont);
}
// Draw the glyph bounds
if ((self.showsGlyphBounds) != 0) {
CGRect glyphBounds = CTRunGetImageBounds(run, context, glyphRange);
CGContextSetRGBStrokeColor(context, 0.0, 0.0, 1.0, 1.0);
CGContextStrokeRect(context, glyphBounds);
}
// Draw the bounding boxes defined by the line metrics
if ((self.showsLineMetrics) != 0) {
CGRect lineMetrics;
CGFloat ascent, descent;
CTRunGetTypographicBounds(run, glyphRange, &ascent, &descent, NULL);
// The glyph is centered around the y-axis
lineMetrics.origin.x = -halfGlyphWidth;
lineMetrics.origin.y = positionForThisGlyph.y - descent;
lineMetrics.size.width = glyphWidth;
lineMetrics.size.height = ascent + descent;
CGContextSetRGBStrokeColor(context, 0.0, 1.0, 0.0, 1.0);
CGContextStrokeRect(context, lineMetrics);
}
}
glyphOffset += runGlyphCount;
}
CGContextRestoreGState(context);
free(glyphArcInfo);
CFRelease(line);
}
-(void)dealloc
{
[_font release];
[_string release];
[_color release];
[super dealloc]
}
@synthesize font = _font;
@synthesize text = _string;
@synthesize radius = _radius;
@synthesize color = _color;
@synthesize arcSize = _arcSize;
@synthesize shiftH = _shiftH;
@synthesize shiftV = _shiftV;
@dynamic attributedString;
- (NSAttributedString *)attributedString {
// Create an attributed string with the current font and string.
assert(self.font != nil);
assert(self.text != nil);
// Create our attributes...
// font
CTFontRef fontRef = CTFontCreateWithName((CFStringRef)self.font.fontName, self.font.pointSize, NULL);
// color
CGColorRef colorRef = self.color.CGColor;
// pack it into attributes dictionary
NSDictionary *attributesDict = [NSDictionary dictionaryWithObjectsAndKeys:
(id)fontRef, (id)kCTFontAttributeName,
colorRef, (id)kCTForegroundColorAttributeName,
nil];
assert(attributesDict != nil);
// Create the attributed string
NSAttributedString *attrString = [[NSAttributedString alloc] initWithString:self.text attributes:attributesDict];
CFRelease(fontRef);
return [attrString autorelease];
}
@dynamic showsGlyphBounds;
- (BOOL)showsGlyphBounds {
return _flags.showsGlyphBounds;
}
- (void)setShowsGlyphBounds:(BOOL)show {
_flags.showsGlyphBounds = show ? 1 : 0;
}
@dynamic showsLineMetrics;
- (BOOL)showsLineMetrics {
return _flags.showsLineMetrics;
}
- (void)setShowsLineMetrics:(BOOL)show {
_flags.showsLineMetrics = show ? 1 : 0;
}
@dynamic dimsSubstitutedGlyphs;
- (BOOL)dimsSubstitutedGlyphs {
return _flags.dimsSubstitutedGlyphs;
}
- (void)setDimsSubstitutedGlyphs:(BOOL)dim {
_flags.dimsSubstitutedGlyphs = dim ? 1 : 0;
}
@end
-(void)layoutSublayersOfLayer:(CALayer*)layer
{
if ( layer != self.layer )
{
return;
}
self.layer.sublayers = nil;
LOG( @"Laying out sublayers..." );
CGFloat xcenter = self.frame.size.width / 2;
CGFloat ycenter = self.frame.size.height / 2;
float angle = arcStart;
float angleStep = arcSize / [self.text length];
for ( NSUInteger i = 0; i < [self.text length]; ++i )
{
NSRange range = { .location = i, .length = 1 };
NSString* c = [self.text substringWithRange:range];
CGFloat yoffset = sin( DEGREES_TO_RADIANS(angle) ) * radius;
CGFloat xoffset = cos( DEGREES_TO_RADIANS(angle) ) * radius;
CGFloat rotAngle = 90 - angle;
if ( clockwise )
{
yoffset = -yoffset;
rotAngle = -90 + angle;
}
CATextLayer* tl = [[CATextLayer alloc] init];
if ( debugMode )
{
tl.borderWidth = 1;
tl.cornerRadius = 3;
tl.borderColor = [UIColor whiteColor].CGColor;
}
tl.frame = CGRectMake( shiftH + xcenter - xoffset, shiftV + ycenter + yoffset, 20, 20 );
tl.font = self.font.fontName;
tl.fontSize = self.font.pointSize;
tl.foregroundColor = self.color.CGColor;
tl.string = c;
tl.alignmentMode = @"center";
tl.transform = CATransform3DMakeAffineTransform( CGAffineTransformMakeRotation( DEGREES_TO_RADIANS(rotAngle) ) );
if ( debugMode )
{
CATextLayer* debugLayer = [self debugLayerWithText:[NSString stringWithFormat:@"%u: %.0f°", i, angle]];
debugLayer.transform = CATransform3DMakeAffineTransform( CGAffineTransformMakeRotation( DEGREES_TO_RADIANS(-rotAngle) ) );
[tl addSublayer:debugLayer];
}
[self.layer addSublayer:tl];
angle += angleStep;
}
}
- (id)initWithFrame:(CGRect)frame font:(UIFont *)font text:(NSString *)text radius:(float)radius arcSize:(float)arcSize color:(UIColor *)color;
- (void)sizeToFit{
[super sizeToFit];
CGFloat width = ceilf( fabsf((self.radius*2)) + self.font.lineHeight) + 3.0;
CGRect f = self.frame;
f.size = CGSizeMake(width,width);
self.frame = f;
[self setNeedsDisplay];
}
CGContextTranslateCTM(context, CGRectGetMidX(rect)+_shiftH, CGRectGetMidY(rect)+_shiftV - self.radius / 2.0);
CGContextTranslateCTM(context, CGRectGetMidX(rect)+_shiftH, CGRectGetMidY(rect)+_shiftV);
CGContextRotateCTM(context, _arcSize/2.0);
CGContextRotateCTM(context, M_PI_2);
- (id)initWithFrame:(CGRect)frame font:(UIFont *)font text:(NSString *)text color:(UIColor *)color{
self = [super initWithFrame:frame];
if (self) {
self.font = font;
self.text = text;
self.radius = -1 * (frame.size.width > frame.size.height ? frame.size.height / 2 : frame.size.width / 2);
_arcSize = 2* M_PI;
self.showsGlyphBounds = NO;
self.showsLineMetrics = NO;
self.dimsSubstitutedGlyphs = NO;
self.color = color;
self.shiftH = self.shiftV = 0.0f;
}
return self;
}
// this constants come from a single case ( fontSize = 22 | circle diameter = 250px | lower circle diameter 50px | 0.12f is a proportional acceptable value of 250px diameter | 0.18f is a proportional acceptable value of 50px | 0.035f is a proportional acceptable value of "big" chars
#define kReferredCharSpacing 0.12f
#define kReferredFontSize 22.f
#define kReferredMajorDiameter 250.f
#define kReferredMinorDiameter 50.f
#define kReferredMinorSpacingFix 0.18f
#define kReferredBigCharSpacingFix 0.035f
static void PrepareGlyphArcInfo(UIFont* font,CGFloat containerRadius,CTLineRef line, CFIndex glyphCount, GlyphArcInfo *glyphArcInfo, CGFloat arcSizeRad)
{
NSArray *runArray = (NSArray *)CTLineGetGlyphRuns(line);
CGFloat curMaxTypoWidth = 0.f;
CGFloat curMinTypoWidth = 0.f;
// Examine each run in the line, updating glyphOffset to track how far along the run is in terms of glyphCount.
CFIndex glyphOffset = 0;
for (id run in runArray) {
CFIndex runGlyphCount = CTRunGetGlyphCount((CTRunRef)run);
// Ask for the width of each glyph in turn.
CFIndex runGlyphIndex = 0;
for (; runGlyphIndex < runGlyphCount; runGlyphIndex++) {
glyphArcInfo[runGlyphIndex + glyphOffset].width = CTRunGetTypographicBounds((CTRunRef)run, CFRangeMake(runGlyphIndex, 1), NULL, NULL, NULL);
if (curMaxTypoWidth < glyphArcInfo[runGlyphIndex + glyphOffset].width)
curMaxTypoWidth = glyphArcInfo[runGlyphIndex + glyphOffset].width;
if (curMinTypoWidth > glyphArcInfo[runGlyphIndex + glyphOffset].width || curMinTypoWidth == 0)
curMinTypoWidth = glyphArcInfo[runGlyphIndex + glyphOffset].width;
}
glyphOffset += runGlyphCount;
}
//double lineLength = CTLineGetTypographicBounds(line, NULL, NULL, NULL);
glyphArcInfo[0].angle = M_PI_2; // start at the bottom circle
CFIndex lineGlyphIndex = 1;
// based on font size. (supposing that with fontSize = 22 we could use 0.12)
CGFloat maxCharSpacing = font.pointSize * kReferredCharSpacing / kReferredFontSize;
// for diameter minor than referred 250
if ((fabsf(containerRadius)*2) < kReferredMajorDiameter)
maxCharSpacing = maxCharSpacing + kReferredMinorSpacingFix * kReferredMinorDiameter / (fabsf(containerRadius)*2);
CGFloat startAngle = fabsf(glyphArcInfo[0].angle);
CGFloat endAngle = startAngle;
for (; lineGlyphIndex < glyphCount; lineGlyphIndex++) {
CGFloat deltaWidth = curMaxTypoWidth - glyphArcInfo[lineGlyphIndex].width;
// fix applied to large characters like uppercase letters or symbols
CGFloat bigCharFix = (glyphArcInfo[lineGlyphIndex-1].width == curMaxTypoWidth || (glyphArcInfo[lineGlyphIndex-1].width+2) >= curMaxTypoWidth ? kReferredBigCharSpacingFix : 0 );
glyphArcInfo[lineGlyphIndex].angle = - (maxCharSpacing * (glyphArcInfo[lineGlyphIndex].width + deltaWidth ) / curMaxTypoWidth) - bigCharFix;
endAngle += fabsf(glyphArcInfo[lineGlyphIndex].angle);
}
// center text to bottom
glyphArcInfo[0].angle = glyphArcInfo[0].angle + (endAngle - startAngle ) / 2;
}
- (void)drawRect:(CGRect)rect {
// Don't draw if we don't have a font or string
if (self.font == NULL || self.text == NULL)
return;
// Initialize the text matrix to a known value
CGContextRef context = UIGraphicsGetCurrentContext();
//Reset the transformation
//Doing this means you have to reset the contentScaleFactor to 1.0
CGAffineTransform t0 = CGContextGetCTM(context);
CGFloat xScaleFactor = t0.a > 0 ? t0.a : -t0.a;
CGFloat yScaleFactor = t0.d > 0 ? t0.d : -t0.d;
t0 = CGAffineTransformInvert(t0);
if (xScaleFactor != 1.0 || yScaleFactor != 1.0)
t0 = CGAffineTransformScale(t0, xScaleFactor, yScaleFactor);
CGContextConcatCTM(context, t0);
CGContextSetTextMatrix(context, CGAffineTransformIdentity);
NSAttributedString *attStr = self.attributedString;
CFAttributedStringRef asr = (CFAttributedStringRef)attStr;
CTLineRef line = CTLineCreateWithAttributedString(asr);
assert(line != NULL);
CFIndex glyphCount = CTLineGetGlyphCount(line);
if (glyphCount == 0) {
CFRelease(line);
return;
}
GlyphArcInfo * glyphArcInfo = (GlyphArcInfo*)calloc(glyphCount, sizeof(GlyphArcInfo));
PrepareGlyphArcInfo(self.font, self.radius, line, glyphCount, glyphArcInfo, _arcSize);
// Move the origin from the lower left of the view nearer to its center.
CGContextSaveGState(context);
CGContextTranslateCTM(context, CGRectGetMidX(rect)+_shiftH, CGRectGetMidY(rect)+_shiftV);
if(ARCVIEW_DEBUG_MODE){
// Stroke the arc in red for verification.
CGContextBeginPath(context);
CGContextAddArc(context, 0.0, 0.0, self.radius, M_PI_2+_arcSize/2.0, M_PI_2-_arcSize/2.0, 1);
CGContextSetRGBStrokeColor(context, 1.0, 0.0, 0.0, 1.0);
CGContextStrokePath(context);
}
// Rotate the context 90 degrees counterclockwise (per 180 degrees)
CGContextRotateCTM(context, M_PI_2);
// Now for the actual drawing. The angle offset for each glyph relative to the previous glyph has already been calculated; with that information in hand, draw those glyphs overstruck and centered over one another, making sure to rotate the context after each glyph so the glyphs are spread along a semicircular path.
CGPoint textPosition = CGPointMake(0.0, self.radius);
CGContextSetTextPosition(context, textPosition.x, textPosition.y);
CFArrayRef runArray = CTLineGetGlyphRuns(line);
CFIndex runCount = CFArrayGetCount(runArray);
CFIndex glyphOffset = 0;
CFIndex runIndex = 0;
for (; runIndex < runCount; runIndex++) {
CTRunRef run = (CTRunRef)CFArrayGetValueAtIndex(runArray, runIndex);
CFIndex runGlyphCount = CTRunGetGlyphCount(run);
Boolean drawSubstitutedGlyphsManually = false;
CTFontRef runFont = CFDictionaryGetValue(CTRunGetAttributes(run), kCTFontAttributeName);
// Determine if we need to draw substituted glyphs manually. Do so if the runFont is not the same as the overall font.
if (self.dimsSubstitutedGlyphs && ![self.font isEqual:(UIFont *)runFont]) {
drawSubstitutedGlyphsManually = true;
}
CFIndex runGlyphIndex = 0;
for (; runGlyphIndex < runGlyphCount; runGlyphIndex++) {
CFRange glyphRange = CFRangeMake(runGlyphIndex, 1);
CGContextRotateCTM(context, -(glyphArcInfo[runGlyphIndex + glyphOffset].angle));
// Center this glyph by moving left by half its width.
CGFloat glyphWidth = glyphArcInfo[runGlyphIndex + glyphOffset].width;
CGFloat halfGlyphWidth = glyphWidth / 2.0;
CGPoint positionForThisGlyph = CGPointMake(textPosition.x - halfGlyphWidth, textPosition.y);
// Glyphs are positioned relative to the text position for the line, so offset text position leftwards by this glyph's width in preparation for the next glyph.
textPosition.x -= glyphWidth;
CGAffineTransform textMatrix = CTRunGetTextMatrix(run);
textMatrix.tx = positionForThisGlyph.x;
textMatrix.ty = positionForThisGlyph.y;
CGContextSetTextMatrix(context, textMatrix);
CTRunDraw(run, context, glyphRange);
}
glyphOffset += runGlyphCount;
}
CGContextSetFillColorWithColor(context, [UIColor clearColor].CGColor);
CGContextSetAlpha(context,0.0);
CGContextFillRect(context, rect);
CGContextRestoreGState(context);
free(glyphArcInfo);
CFRelease(line);
}
[self drawCurvedStringOnLayer:self.layer withAttributedText:incident atAngle:angle withRadius:300];
- (void)drawCurvedStringOnLayer:(CALayer *)layer
withAttributedText:(NSAttributedString *)text
atAngle:(float)angle
withRadius:(float)radius {
// angle in radians
CGSize textSize = CGRectIntegral([text boundingRectWithSize:CGSizeMake(CGFLOAT_MAX, CGFLOAT_MAX)
options:(NSStringDrawingUsesLineFragmentOrigin|NSStringDrawingUsesFontLeading)
context:nil]).size;
float perimeter = 2 * M_PI * radius;
float textAngle = (textSize.width / perimeter * 2 * M_PI);
float textRotation;
float textDirection;
if (angle > degreesToRadians(10) && angle < degreesToRadians(170)) {
//bottom string
textRotation = 0.5 * M_PI ;
textDirection = - 2 * M_PI;
angle += textAngle / 2;
} else {
//top string
textRotation = 1.5 * M_PI ;
textDirection = 2 * M_PI;
angle -= textAngle / 2;
}
for (int c = 0; c < text.length; c++) {
NSRange range = {c, 1};
NSAttributedString* letter = [text attributedSubstringFromRange:range];
CGSize charSize = CGRectIntegral([letter boundingRectWithSize:CGSizeMake(CGFLOAT_MAX, CGFLOAT_MAX)
options:(NSStringDrawingUsesLineFragmentOrigin|NSStringDrawingUsesFontLeading)
context:nil]).size;
float letterAngle = ( (charSize.width / perimeter) * textDirection );
float x = radius * cos(angle + (letterAngle/2));
float y = radius * sin(angle + (letterAngle/2));
CATextLayer *singleChar = [self drawTextOnLayer:layer
withText:letter
frame:CGRectMake(layer.frame.size.width/2 - charSize.width/2 + x,
layer.frame.size.height/2 - charSize.height/2 + y,
charSize.width, charSize.height)
bgColor:nil
opacity:1];
singleChar.transform = CATransform3DMakeAffineTransform( CGAffineTransformMakeRotation(angle - textRotation) );
angle += letterAngle;
}
}
- (CATextLayer *)drawTextOnLayer:(CALayer *)layer
withText:(NSAttributedString *)text
frame:(CGRect)frame
bgColor:(UIColor *)bgColor
opacity:(float)opacity {
CATextLayer *textLayer = [[CATextLayer alloc] init];
[textLayer setFrame:frame];
[textLayer setString:text];
[textLayer setAlignmentMode:kCAAlignmentCenter];
[textLayer setBackgroundColor:bgColor.CGColor];
[textLayer setContentsScale:[UIScreen mainScreen].scale];
[textLayer setOpacity:opacity];
[layer addSublayer:textLayer];
return textLayer;
}
/** Degrees to Radian **/
#define degreesToRadians(degrees) (( degrees ) / 180.0 * M_PI )
/** Radians to Degrees **/
#define radiansToDegrees(radians) (( radians ) * ( 180.0 / M_PI ) )
#import <Cocoa/Cocoa.h>
@interface CircleTextCell : NSCell {
}
@end
#import "CircleTextCell.h"
#define PI (3.141592653589793)
@implementation CircleTextCell
- (void)drawWithFrame: (NSRect)cellFrame inView: (NSView*)controlView
{
NSAttributedString *str = [self attributedStringValue];
NSSize stringSize = [str size];
NSUInteger chars = [[str string] length];
CGFloat radius = (stringSize.width + 5 * chars) / (2 * PI);
CGFloat diameter = 2*radius;
NSPoint scale = {1,1};
if (diameter > cellFrame.size.width)
{
scale.x = cellFrame.size.width / diameter;
}
if (diameter > cellFrame.size.height)
{
scale.y = cellFrame.size.height / diameter;
}
NSAffineTransform *transform = [NSAffineTransform transform];
NSAffineTransformStruct identity = [transform transformStruct];
[transform scaleXBy: scale.x yBy: scale.y];
[transform translateXBy: radius yBy: 0];
[NSGraphicsContext saveGraphicsState];
[transform concat];
NSPoint origin = {0,0};
CGFloat angleScale = 360 / (stringSize.width + (5 * chars));
for (NSUInteger i=0 ; i<chars ; i++)
{
NSAttributedString *substr =
[str attributedSubstringFromRange: NSMakeRange(i, 1)];
[substr drawAtPoint: origin];
[transform setTransformStruct: identity];
CGFloat displacement = [substr size].width + 5;
[transform translateXBy: displacement yBy: 0];
[transform rotateByDegrees: angleScale * displacement];
[transform concat];
}
[NSGraphicsContext restoreGraphicsState];
}
@end
#import <Cocoa/Cocoa.h>
@class CircleTextCell;
@interface CircleTextView : NSView {
CircleTextCell *cell;
}
@end
#import "CircleTextView.h"
#import "CircleTextCell.h"
@implementation CircleTextView
- (void)awakeFromNib
{
NSDictionary *attributes =
[NSDictionary dictionaryWithObject: [NSFont fontWithName: @"Zapfino"
size:32]
forKey: NSFontAttributeName];
NSAttributedString *str =
[[NSAttributedString alloc] initWithString: @"Hello World! This is a very long text string that will be wrapped into a circle by a cell drawn in a custom view"
attributes: attributes];
cell = [[CircleTextCell alloc] init];
[cell setAttributedStringValue: str];
}
- (void)drawRect:(NSRect)rect
{
[[NSColor whiteColor] setFill];
[NSBezierPath fillRect: rect];
[cell drawWithFrame: [self bounds] inView: self];
}
@end