我正在创作绘画..我可以撤消，并在上面添加颜色。但是当我用我的手指画画时，笔画不是那么平滑并且有边缘线，
这是我的代码。我可以在视图上绘制，撤消，更改颜色和不透明度。
stroke.h
#import <UIKit/UIKit.h>
@interface stroke : UIView{
NSMutableArray *strokeArray;
UIColor *strokeColor;
int strokeSize;
float strokeAlpha;
int strokeAlpha2;
IBOutlet UISlider *slides;
float red;
float green;
float blue;
CGPoint mid1;
CGPoint mid2;
CGPoint endingPoint,previousPoint1,previousPoint2;
CGPoint currentTouch;
}
@property (nonatomic, retain) UIColor *strokeColor;
@property (nonatomic) int strokeSize;
@property (nonatomic, retain) NSMutableArray *strokeArray;
- (IBAction)changeAlphaValue;
-(void)loadSLider;
-(void)blueColor;
-(void)darkvioletColor;
-(void)violetColor;
-(void)pinkColor;
-(void)darkbrownColor;
-(void)redColor;
-(void)magentaRedColor;
-(void)lightBrownColor;
-(void)lightOrangeColor;
-(void)OrangeColor;
-(void)YellowColor;
-(void)greenColor;
-(void)lightYellowColor;
-(void)darkGreenColor;
-(void)TurquioseColor;
-(void)PaleTurquioseColor;
-(void)skyBlueColor;
-(void)whiteColor;
-(void)DirtyWhiteColor;
-(void)SilverColor;
-(void)LightGrayColor;
-(void)GrayColor;
-(void)LightBlackColor;
-(void)BlackColor;
@end
stroke.m
#import "stroke.h"
@implementation stroke
@synthesize strokeColor;
@synthesize strokeSize;
@synthesize strokeArray;
- (void) awakeFromNib{
self.strokeArray = [[NSMutableArray alloc] init];
self.strokeColor = [UIColor colorWithRed:0 green:0 blue:232 alpha:1];
self.strokeSize = 3;
}
- (void)drawRect:(CGRect)rect{
NSMutableArray *stroke;
for (stroke in strokeArray) {
CGContextRef contextRef = UIGraphicsGetCurrentContext();
CGContextSetLineWidth(contextRef, [[stroke objectAtIndex:1] intValue]);
CGFloat *color = CGColorGetComponents([[stroke objectAtIndex:2] CGColor]);
CGContextSetRGBStrokeColor(contextRef, color[0], color[1], color[2], color[3]);
CGContextBeginPath(contextRef);
CGPoint points[[stroke count]];
for (NSUInteger i = 3; i < [stroke count]; i++) {
points[i-3] = [[stroke objectAtIndex:i] CGPointValue];
}
CGContextAddLines(contextRef, points, [stroke count]-3);
CGContextStrokePath(contextRef);
}
}
-(void)loadSLider{
}
- (IBAction)changeAlphaValue{
strokeAlpha2 =((int)slides.value);
}
-(void)blueColor{
red = 0/255.0;
green = 0/255.0;
blue = 255/255.0;
}
-(void)darkvioletColor{
red = 75/255.0;
green = 0/255.0;
blue = 130/255.0;
}
-(void)violetColor{
red = 128/255.0;
green = 0/255.0;
blue = 128/255.0;
}
-(void)pinkColor{
red = 255/255.0;
green = 0/255.0;
blue = 255/255.0;
}
-(void)darkbrownColor{
red = 0.200;
green = 0.0;
blue = 0.0;
}
-(void)redColor{
red = 255/255.0;
green = 0/255.0;
blue = 0/255.0;
}
-(void)magentaRedColor{
red = 0.350;
green = 0.0;
blue = 0.0;
}
-(void)lightBrownColor{
red = 0.480;
green = 0.0;
blue = 0.0;
}
-(void)lightOrangeColor{
red = 0.600;
green = 0.200;
blue = 0.0;
}
-(void)OrangeColor{
red = 1.0;
green = 0.300;
blue = 0.0;
}
-(void)YellowColor{
red = 0.950;
green = 0.450;
blue = 0.0;
}
-(void)greenColor{
red = 0.0;
green = 1.0;
blue = 0.0;
}
-(void)lightYellowColor{
red = 1.0;
green = 1.0;
blue = 0.0;
}
-(void)darkGreenColor{
red = 0.0;
green = 0.500;
blue = 0.0;
}
-(void)TurquioseColor{
red = 0.0;
green = 0.700;
blue = 0.200;
}
-(void)PaleTurquioseColor{
red = 0.0;
green = 0.700;
blue = 0.600;
}
-(void)skyBlueColor{
red = 0.0;
green = 0.400;
blue = 0.800;
}
-(void)whiteColor{
red = 1.0;
green = 1.0;
blue = 1.0;
}
-(void)DirtyWhiteColor{
red = 0.800;
green = 0.800;
blue = 0.800;
}
-(void)SilverColor{
red = 0.600;
green = 0.600;
blue = 0.600;
}
-(void)LightGrayColor{
red = 0.500;
green = 0.500;
blue = 0.500;
}
-(void)GrayColor{
red = 0.300;
green = 0.300;
blue = 0.300;
}
-(void)LightBlackColor{
red = 0.150;
green = 0.150;
blue = 0.150;
}
-(void)BlackColor{
red = 0.0;
green = 0.0;
blue = 0.0;
}
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch;
NSEnumerator *counter = [touches objectEnumerator];
while ((touch = (UITouch *)[counter nextObject])) {
switch (strokeAlpha2) {
case 1:
strokeAlpha = .1;
break;
case 2:
strokeAlpha = .2;
break;
case 3:
strokeAlpha = .3;
break;
case 4:
strokeAlpha = .4;
break;
case 5:
strokeAlpha = .5;
break;
case 6:
strokeAlpha = .6;
break;
case 7:
strokeAlpha = .7;
break;
case 8:
strokeAlpha = .8;
break;
case 9:
strokeAlpha = .9;
break;
case 10:
strokeAlpha = 1;
break;
default:
strokeAlpha = 1;
break;
}
self.strokeColor = [UIColor colorWithRed:red green:green blue:blue alpha:strokeAlpha];
NSValue *touchPos = [NSValue valueWithCGPoint:[touch locationInView:self]];
UIColor *color = [UIColor colorWithCGColor:strokeColor.CGColor];
NSNumber *size = [NSNumber numberWithInt:strokeSize];
NSMutableArray *stroke = [NSMutableArray arrayWithObjects: touch, size, color, touchPos, nil];
[strokeArray addObject:stroke];
}
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch;
NSEnumerator *counter = [touches objectEnumerator];
while ((touch = (UITouch *)[counter nextObject])) {
NSMutableArray *stroke;
for (stroke in strokeArray) {
if ([stroke objectAtIndex:0] == touch) {
[stroke addObject:[NSValue valueWithCGPoint:[touch locationInView:self]]];
}
[self setNeedsDisplay];
}
}
}
@end
答案 0 :(得分：0)
不应使用CGContextAddLines()，而应使用CGContextAddCurveToPoint()创建贝塞尔路径。你需要用4个点构建它，所以你可能需要使用前一个和后两个点，或者沿着这些点的东西。