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Gradient rendering issue with alpha set to something other than one
Gradients with colors that have alpha are not rendered correctly anymore. I made a simple project to illustrate that. Just create Objective C project and paste this code inside the ViewController. `#import <UIKit/UIKit.h> @interface CustomView : UIView @property (nonatomic, strong) NSArray<NSNumber *> *colorsArray; // The color components array // Custom initializer that accepts an NSArray of color components (instancetype)initWithFrame:(CGRect)frame colors:(NSArray<NSNumber *> *)colorsArray; @end @implementation CustomView // Custom initializer (instancetype)initWithFrame:(CGRect)frame colors:(NSArray<NSNumber *> *)colorsArray { self = [super initWithFrame:frame]; if (self) { _colorsArray = colorsArray; // Store the colors array } return self; } (void)drawRect:(CGRect)rect { // Get the current context CGContextRef context = UIGraphicsGetCurrentContext(); // Convert NSArray to a C-style array of CGFloats size_t count = self.colorsArray.count; CGFloat colors[count]; for (size_t i = 0; i < count; i++) { colors[i] = [self.colorsArray[i] floatValue]; } // Create a color space CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB(); // Create the gradient with the passed colors CGGradientRef gradient = CGGradientCreateWithColorComponents(colorSpace, colors, NULL, count / 4); // Define the start and end points of the gradient CGPoint startPoint = CGPointMake(rect.origin.x, rect.origin.y); CGPoint endPoint = CGPointMake(rect.origin.x, rect.origin.y + rect.size.height); // Draw the rectangle with the gradient CGContextSaveGState(context); CGContextAddRect(context, rect); CGContextClip(context); CGContextDrawLinearGradient(context, gradient, startPoint, endPoint, 0); CGContextRestoreGState(context); // Release resources CGGradientRelease(gradient); CGColorSpaceRelease(colorSpace); } @end @interface ViewController : UIViewController @end @implementation ViewController (void)viewDidLoad { [super viewDidLoad]; // Get the screen bounds CGRect screenBounds = [UIScreen mainScreen].bounds; // Define the size of each custom view CGFloat customViewWidth = screenBounds.size.width * 0.75; CGFloat customViewHeight = screenBounds.size.height * 0.75; // Define a dynamic set of colors for the first custom view (red to blue) NSArray<NSNumber *> *colorsArray1 = @[ @1.0, @0.0, @0.0, @1.0, // Red @0.0, @0.0, @1.0, @1.0 // Blue ]; // TODO: This is the bug, there is no transparency NSNumber *alpha = @0.0;// this is the ***** bug **** // Define a dynamic set of colors for the second custom view (green to yellow) NSArray<NSNumber *> *colorsArray2 = @[ @0.0, @1.0, @0.0, alpha, // Green @1.0, @1.0, @0.0, @1.0 // Yellow ]; // Calculate the position for the first view (centered horizontally and vertically, with slight offset) CGRect frame1 = CGRectMake((screenBounds.size.width - customViewWidth) / 2 - customViewWidth * 0.25, (screenBounds.size.height - customViewHeight) / 2 - customViewHeight * 0.25, customViewWidth, customViewHeight); CustomView *customView1 = [[CustomView alloc] initWithFrame:frame1 colors:colorsArray1]; // Calculate the position for the second view (slightly shifted from the first view to partially overlap) CGRect frame2 = CGRectMake((screenBounds.size.width - customViewWidth) / 2 + customViewWidth * 0.25, (screenBounds.size.height - customViewHeight) / 2 + customViewHeight * 0.25, customViewWidth, customViewHeight); CustomView *customView2 = [[CustomView alloc] initWithFrame:frame2 colors:colorsArray2]; // Set autoresizing so they adjust with the screen size customView1.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight; customView2.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight; // Add the custom views to the view controller's view [self.view addSubview:customView1]; [self.view addSubview:customView2]; } @end`
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165
Oct ’24
Xcode 11.3 running on Mac 10.14.6 (18G95) can't compile on devices
My project is huge and I started getting compilation errors all of a sudden on devices (compiling for simulators are fine). So I made a new empty project with one line of code that compiles fine on the simulator but can't on the device. Here is the code:- (void)viewDidLoad { [super viewDidLoad]; // This line compiles fine on simulator but not on device. float s = roundf(233.33); } Error is:- Implicitly declaring library function 'roundf' with type 'float (float)'
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470
Jul ’20