exavolt

Modularizing your apps

Why do we want modularize our apps? Jump to the last section of this article for the rationale.

Imagine we have a two app projects. One of them is a task management app (tasker) while the other is a chat app (messenger).

We have this for the tasker app:

.
├── models

exavolt

FROM golang:1.13-alpine

# VARIANT can be either 'hugo' for the standard version or 'hugo_extended' for the extended version.
ARG VARIANT=hugo_extended
# VERSION can be either 'latest' or a specific version number
ARG VERSION=latest

RUN apk add --update --no-cache ca-certificates openssl git curl && \
    case ${VERSION} in \
    latest) \

exavolt

Choice Chip Bar for Flutter

While Flutter already provides ChoiceChip, it's a bare-bone component. We would need to wire them ourselves to create a group of choices. This widget, ChoiceChipBar, means to provide a self-contained widget for a group of choice chips, so the ancestor widget won't need to manage the state; just provide the choices and a callback to onChanged.

exavolt

// source
// https://github.com/filipeglfw/material-palette-generator/blob/master/src/index.js

import 'dart:math' as math;

// Main API.
//
//   generateMaterialPalette(RGBColor.fromInt(0xffe91e63)).map<Color>((c) => Color(c.toInt()));
//
List<RGBColor> generateMaterialPalette(RGBColor rgbColor) {

exavolt

import 'package:flutter/material.dart';
import 'package:shared_preferences/shared_preferences.dart';

// Wrap your application instance with this class.
//
//   class MyApp extends StatelessWidget {
//     // This widget is the root of your application.
//     @override
//     Widget build(BuildContext context) {
//       return ThemeModeApp((BuildContext context, ThemeMode themeMode) {

exavolt

//

import 'package:flutter/material.dart';

class ColorChoiceController extends ValueNotifier<ColorChoiceValue> {
  ColorChoiceController([int index])
      : super(index != null ? ColorChoiceValue(index) : null);

  Color get color => this.value?.color;

exavolt

package main

import (
	"fmt"
	"path/filepath"
	"strings"

	"gopkg.in/src-d/go-billy.v4/osfs"
	"gopkg.in/src-d/go-git.v4"
	"gopkg.in/src-d/go-git.v4/plumbing/cache"

exavolt

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <math.h>

#include <SDL2/SDL.h>
#include <SDL2/SDL_opengl.h>

exavolt

// ported from http://alienryderflex.com/intersect/

public static function LineIntersection(a:Point, b:Point, c:Point, d:Point):Point
{
	var distAB:Number, cos:Number, sin:Number, newX:Number, ABpos:Number;
	if ((a.x == b.x && a.y == b.y) || (c.x == d.x && c.y == d.y)) return null;

	if ( a == c || a == d || b == c || b == d ) return null;

	b = b.clone();

exavolt

Di sini kita akan membahas seputar pergerakan object di dalam game yang digerakkan dengan cara mengklik titik tujuan kemana object harus bergerak. Cara input seperti ini banyak digunakan untuk game-game RTS dan RPG.

Secara garis besar bisa kita jelaskan sebagai: menggerakkan object ke arah yang dituju. Cukup simpel. Tapi kalo menggampangkan, hasilnya tidak seperti yang kita harapkan; misal, ketika sampai di tujuan, object-nya bergerak bolak-balik.

Semisal object yang akan kita gerakkan berada di posisi A. Kita ingin menggerakkan object ini ke titik B.

Pertama kali, simpan titik tujuan ini, koordinat titik B, sebagai atribute dari sang object.

Langkah selanjutnya kita lakukan adalah mengurangkan koordinat titik tujuan dengan koordinat titik awal. Di sini kita akan mendapatkan (non-normalized) vector dari titik awal ke titik tujuan.