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JoshuaSullivan / Outputter.swift
Created June 1, 2024 14:58
Function to write image directly to URL
import Foundation
import UIKit
import CoreImage
import Metal
class Outputter {
private lazy var context: CIContext = {
guard
let device = MTLCreateSystemDefaultDevice(),
@JoshuaSullivan
JoshuaSullivan / Renderer.swift
Created May 28, 2024 14:46
Metal-backed CoreImage Renderer
import UIKit
import CoreImage
import Metal
public class Renderer {
public enum Error: Swift.Error {
case failedToCreateRenderer
case infiniteRenderRect
case failedToRenderImage
@JoshuaSullivan
JoshuaSullivan / Grid.swift
Last active May 10, 2024 15:57
A data structure representing a 2D grid of homogeneous values. Has methods for examining data geometrically and avoids out-of-range exceptions that are common when working with Arrays.
/// Represents a point on a grid.
///
/// - Note: Instances of this type are not bound to any particular Grid and may be invalid depending on the size of the grid.
///
public struct GridCoordinate: Equatable, Hashable, CustomStringConvertible {
/// The origin point of the grid.
public static let zero = GridCoordinate(x: 0, y: 0)
/// The column (East/West) position of this coordinate.
@JoshuaSullivan
JoshuaSullivan / midjourney-quickstart.md
Last active July 29, 2023 20:55
Midjourney Quick-Start Guide

Midjourney Quick-Start Guide

Midjourney is a commercial image generation and transformation AI service. Similar services include:

  • DALL-E 2 (Microsoft)
  • Nightcafe
  • Stable Diffusion (Open Source)

Midjourney is a somewhat opinionated AI and tends to try to create "art". It has a very high level of coherence, which means elements in the resulting images tend to have natural relationships with a low level of glitches and random weirdness. In my opinion, Midjourney has much higher quality "out of the box", trouncing the competition unless the user is quite advanced at effectively utilizing both positive and negative prompt particles.

@JoshuaSullivan
JoshuaSullivan / DataParser.swift
Last active November 21, 2020 17:13
A helper for translating Advent of Code puzzle input into usable values.
import Foundation
/// A type that can be initialized from a string value.
///
public protocol StringInitable {
/// Initialize the object with a string.
///
/// - Note: This operation can fail if the string is not valid for this object type.
///
init?(_ string: String)
@JoshuaSullivan
JoshuaSullivan / ColorAbsoluteDifference.txt
Created October 11, 2020 22:44
Enumerations of the 3 new CoreImage Filters in iOS 14.0
=========================
Color Absolute Difference
=========================
[Availability]
iOS: 14
macOS: 11.0
[Categories]
Color Adjustment, Video, Interlaced, Non-Square Pixels, Still Image, Built-In
@JoshuaSullivan
JoshuaSullivan / CoreImageFilterEnumeration.swift
Created October 11, 2020 22:35
A Swift Playground that will enumerate the properties of all of the CoreImage filters.
import Foundation
import CoreImage
struct FilterInput {
struct ValueRange {
let minValue: Float
let maxValue: Float
let sliderMin: Float?
let sliderMax: Float?
@JoshuaSullivan
JoshuaSullivan / synonym-search.swift
Created March 30, 2020 22:21
Uses the NaturalLanguage framework combined with a thesaurus API to replace adjectives in a sentence with synonyms. This is designed to be run in a Swift Playground.
import UIKit
import NaturalLanguage
import PlaygroundSupport
//: Your secret API key from `https://dictionaryapi.com` goes here.
//: THIS WON'T WORK UNLESS YOU GET A KEY.
let thesaurusKey = ""
//: The string you want to work on.
var testString = "The bright sun set behind the green hills. Thin clouds streaked the red sky."
@JoshuaSullivan
JoshuaSullivan / display-link-combine-playground.swift
Created November 10, 2019 00:14
This gist demonstrates how we can wrap CADisplayLink to get frame refresh events via a published stream rather than the traditional `target:selector:` methodology.
@JoshuaSullivan
JoshuaSullivan / core-image-filters-ios-13.md
Last active March 19, 2024 15:17
An enumeration of iOS 13 Core Image filters.

Core Image Filters

iOS 13 has 218 filters.

New Filters in iOS 13

  • CIDocumentEnhancer
  • CIGaborGradients
  • CIKeystoneCorrectionCombined
  • CIKeystoneCorrectionHorizontal
  • CIKeystoneCorrectionVertical