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Libgdx distance field font support on iOS

Using distance field fonts like explained in the Libgdx wiki: https://github.com/libgdx/libgdx/wiki/Distance-field-fonts
Gives good results on android. I’m using the example shader provided.

But when I run the same program on iOS the text is filled up with white everywhere (see image below).
Is distance field not supported by iOS or do I need to add/change something else to get it to work?

distance field problem

shader code font.vert:

uniform mat4 u_projTrans;

attribute vec4 a_position;
attribute vec2 a_texCoord0;
attribute vec4 a_color;

varying vec4 v_color;
varying vec2 v_texCoord;

void main() {
    gl_Position = u_projTrans * a_position;
    v_texCoord = a_texCoord0;
    v_color = a_color;
}

font.frag:

#ifdef GL_ES
    precision mediump float;
#endif

uniform sampler2D u_texture;

varying vec4 v_color;
varying vec2 v_texCoord;

const float smoothing = 1.0/16.0;

void main() {
    float distance = texture2D(u_texture, v_texCoord).a;
    float alpha = smoothstep(0.5 - smoothing, 0.5 + smoothing, distance);
    gl_FragColor = vec4(v_color.rgb, alpha);
}

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Xcode MyProjectName-Bridging-Header.h does not exist

I want to start using Swift in my Objective-C project. So i added a swift class:

import Foundation
@objc class System : NSObject {
    @objc func printSome() {
        println("Print line System");
    }
}

And imported it into a .m file:

#import "MyProjectName-Swift.h"

When building my project i get the following error:

Bridging header 'PathToMyProject/MyProjectName-Bridging-Header.h' does not exist

NOTE: Under “Build Settings->Swift Compiler – Code Generation->Objective-C Briding Header” is set to MyProjectName-Bridging-Header.h

What should i do to solve this issue?

Any help is much appreciated.

EDIT: Bridging-Header file:
#if defined(__has_include) && __has_include()
# include
#endif

#include <objc/NSObject.h>
#include <stdint.h>
#include <stddef.h>
#include <stdbool.h>

#if defined(__has_include) && __has_include(<uchar.h>)
# include <uchar.h>
#elif __cplusplus < 201103L
typedef uint_least16_t char16_t;
typedef uint_least32_t char32_t;
#endif
#if !defined(SWIFT_PASTE)
# define SWIFT_PASTE_HELPER(x, y) x##y
# define SWIFT_PASTE(x, y) SWIFT_PASTE_HELPER(x, y)
#endif
#if !defined(SWIFT_METATYPE)
# define SWIFT_METATYPE(X) Class
#endif

#if defined(__has_attribute) && __has_attribute(objc_runtime_name)
# define SWIFT_RUNTIME_NAME(X) __attribute__((objc_runtime_name(X)))
#else
# define SWIFT_RUNTIME_NAME(X)
#endif
#if !defined(SWIFT_CLASS_EXTRA)
# define SWIFT_CLASS_EXTRA
#endif
#if !defined(SWIFT_PROTOCOL_EXTRA)
# define SWIFT_PROTOCOL_EXTRA
#endif
#if !defined(SWIFT_CLASS)
# if defined(__has_attribute) && __has_attribute(objc_subclassing_restricted) 
#  define SWIFT_CLASS(SWIFT_NAME) SWIFT_RUNTIME_NAME(SWIFT_NAME) __attribute__((objc_subclassing_restricted)) SWIFT_CLASS_EXTRA
# else
#  define SWIFT_CLASS(SWIFT_NAME) SWIFT_RUNTIME_NAME(SWIFT_NAME) SWIFT_CLASS_EXTRA
# endif
#endif

#if !defined(SWIFT_PROTOCOL)
# define SWIFT_PROTOCOL(SWIFT_NAME) SWIFT_RUNTIME_NAME(SWIFT_NAME) SWIFT_PROTOCOL_EXTRA
#endif

#if !defined(SWIFT_EXTENSION)
# define SWIFT_EXTENSION(M) SWIFT_PASTE(M##_Swift_, __LINE__)
#endif

#if !defined(OBJC_DESIGNATED_INITIALIZER)
# if defined(__has_attribute) && __has_attribute(objc_designated_initializer)
#  define OBJC_DESIGNATED_INITIALIZER __attribute__((objc_designated_initializer))
# else
#  define OBJC_DESIGNATED_INITIALIZER
# endif
#endif
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wproperty-attribute-mismatch"

#if defined(__has_feature) && __has_feature(modules)
#endif

#pragma clang diagnostic pop

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Changing tab bar font in Swift

I have been trying to change the font for the tab bar items however I haven’t been able to find any Swift examples. I know that this is how you change it in Objective-C:

[[UITabBarItem appearance] setTitleTextAttributes:[NSDictionary dictionaryWithObjectsAndKeys:[UIFont fontWithName:@"AmericanTypewriter" size:20.0f], UITextAttributeFont, nil] forState:UIControlStateNormal];

But how can I translate this into Swift?

Changing tab bar font in Swift

How do I convert a Swift Array to a String?

I know how to programmatically do it, but I’m sure there’s a built-in way…

Every language I’ve used has some sort of default textual representation for a collection of objects that it will spit out when you try to concatenate the Array with a string, or pass it to a print() function, etc. Does Apple’s Swift language have a built-in way of easily turning an Array into a String, or do we always have to be explicit when stringifying an array?

How do I convert a Swift Array to a String?

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How can I shuffle bits efficiently?

I need to shuffle a 16 bit unsigned integer in a way that the even indexes land in the lower byte, and the odd indexes land in the upper byte.

input:
fedcba98 76543210 (contiguously numbered)

output:
fdb97531 eca86420 (even and odd separated)

My code looks like this at the moment:

typedef unsigned short u16;

u16 segregate(u16 x)
{
    u16 g = (x & 0x0001);
    u16 h = (x & 0x0004) >> 1;
    u16 i = (x & 0x0010) >> 2;
    u16 j = (x & 0x0040) >> 3;
    u16 k = (x & 0x0100) >> 4;
    u16 l = (x & 0x0400) >> 5;
    u16 m = (x & 0x1000) >> 6;
    u16 n = (x & 0x4000) >> 7;

    u16 o = (x & 0x0002) << 7;
    u16 p = (x & 0x0008) << 6;
    u16 q = (x & 0x0020) << 5;
    u16 r = (x & 0x0080) << 4;
    u16 s = (x & 0x0200) << 3;
    u16 t = (x & 0x0800) << 2;
    u16 u = (x & 0x2000) << 1;
    u16 v = (x & 0x8000);

    return g | h | i | j | k | l | m | n | o | p | q | r | s | t | u | v;
}

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