Saturday, September 30, 2017

Unity tutorial: Optimize removes from List


 If you maintain long List of items in your code and you often need to remove some at arbitrary position within it, then you pay performance penalty as all items with higher index have to be copied one position left.

 This is how code for method List.RemoveAt() looks:

        public void RemoveAt(int index) {
            if ((uint)index >= (uint)_size) {
            if (index < _size) {
                Array.Copy(_items, index + 1, _items, index, _size - index);
            _items[_size] = default(T);

 If item you want to remove is not the last one, then Array.Copy() is called. If your list is long and you are removing items at beginning, then performance costs may be high. But, if you do not care about order of items, you can write simple extension method, that will swap item you want to remove with last item in list and then call RemoveAt() on it. As item to remove is now last one, no copying of array is needed. Here is code for FastRemoveAt method:

using System.Collections.Generic;
using UnityEngine;

public static class ListExtensions {

    public static void FastRemoveAt<T>(this IList<T> list, int index) {
        // fast remove swaps item to remove with last item and then removes it
        // it should avoid internal Array.Copy, but changes order of items in List

        int lastIndex = list.Count - 1;

        T tmp = list[index];
        list[index] = list[lastIndex];
        list[lastIndex] = tmp;


 For test I created list with 100k items. Then, in loop, I remove first item in it and also add new item to the end, so it keeps its length. This is test code:

        // test
        var startTime = Time.realtimeSinceStartup;

        var list = new List<int>();
        var val = 0;

        for (; val < 100000; val++) {

        for (int i = 0; i < 1000000; i++) {

        Debug.Log("Time taken = " + (Time.realtimeSinceStartup - startTime));

 With both methods RemoveAt() and FastRemoveAt() I got these results for various number of updates:

 As you can see, FastRemoveAt() is much faster then RemoveAt().

Sunday, September 17, 2017

Pirates! - the match 3 made it into Apple AppStore


 Our game Pirates! - the match 3 is finally finished and its iOS version just made it into Apple AppStore. You can get it here:

 Pirates! is classic match 3 game with many different tasks for players - dig treasures, open chests, fight enemies or fulfil other tasks you are given in each level. It also features lot of gems combinations to produce various gameplay effects. Graphics for game was made by Tomáš Kopecký and music was composed by Juraj Růžička from SoundRoseStudio.

Flat Jewels Match 3 at Yahoo! Japan


 On 11th September our game Flat Jewels Match 3 was published at Yahoo! Japan. Game was published by Worker Bee Inc. and you can play it on their site here.


Wednesday, July 12, 2017

Fruit Dating at Yahoo! Japan


 Our logical puzzle game Fruit Dating was published at Yahoo! Japan today. It was published by Worker Bee Inc. and you can play it here.

Friday, June 30, 2017

Shards available in Windows Store


 Shards - the brickbreaker is now available in Microsoft's Windows Store as UWP aplication for Windows 10 phones.

Get it on Windows 10

Thursday, June 29, 2017

Shards and Fruit Dating is available on Tizen Store


 In June I rewrote our older games Shards and Fruit Dating into Unity engine. Both are now published at Tizen Store and anyone with Tizen device can download and play them!


Shards at Tizen Store

Fruit Dating

Fruit Dating at Tizen Store

Wednesday, April 19, 2017

New games released: Elsa Jewels, JumpTuber and Brick Stacker


 It has been long since I last posted info about games I finished. So, here is list of games finished or released in first quarter of 2017.

Elsa Jewels

 Elsa Jewels was exclusively made for Famobi. It features popular Disney's characters - Anna and Elsa from Frozen. And yes, Olaf is there too!
 You can play the game here.


 JumpTuber is game to promote local youtuber Jirka Kral. Jirka is running from left to right in his youtuber den, picking likes and hamburgers. He has to avoid ducks and other items thrown at him by other youtubers. Game was made for Gamee platform and you can play it here.

Brick Stacker

 Last game in this list is Brick Stacker. It is another game made for Gamee. You have to build as high tower of blocks as possible. Test your building skills here (it is the best to play it on some device with portrait screen).

Monday, January 23, 2017

Phaser tutorial: How to balance random booleans for game


Previous Phaser tutorials and articles:
Phaser tutorial: Fun with bitmap fonts
Phaser tutorial: Using Spriter player for Phaser
Phaser tutorial: Merging fonts into sprite atlas
Phaser: Typescript defs for Phaser Box2D plugin
Phaser tutorial: Spriter Pro features added to Spriter player for Phaser
Phaser tutorial: Using Phaser signals
Phaser tutorial: Breaking the (z-order) law!
Phaser tutorial: Phaser and Spriter skeletal animation
Phaser tutorial: DronShooter - simple game in Typescript - Part 3
Phaser tutorial: DronShooter - simple game in Typescript - Part 2
Phaser tutorial: adding 9-patch image support to Phaser
Phaser tutorial: DronShooter - simple game in Typescript - Part 1
Phaser tutorial: custom easing functions for tweening and easing functions with parameters
Phaser tutorial: sprites and custom properties for atlas frames
Phaser tutorial: manage different screen sizes
Phaser tutorial: How to wrap bitmap text


 Last year I worked on many small games, were obstacles were generated procedurally on the fly. Getting random numbers from random numbers generator played big role in it. Unfortunately, randomness can be sometimes pretty ... random. Let's say you just want to get randomly true or false to place some obstacle to the right or left. Be sure, that very quickly you will encounter situations, when you will not like the result. Sometimes, there will be too many obstacles on one or other side and game may get boring for long time periods.
 Fast fix may be to add some counters to check if not too many obstacles is on one or other side.
 I was solving this often and to make situation worse, clients had requests like: "I want first 5 obstacles to be left and right in turns, so it will be kind of tutorial for player."


 So, I decided to solve it once and forever with small class, which I named RandomBooleanBalancer. Here is complete code for it in TypeScript:

namespace Helper {

    export class RandomBooleanBalancer {

        private _rnd: Phaser.RandomDataGenerator;
        private _lbound: number;
        private _ubound: number;
        private _currentBalance: number;

        // -------------------------------------------------------------------------
        // balancer - how many consecutive same values maximally
        public constructor(rnd: Phaser.RandomDataGenerator, balancer: number) {
            this._rnd = rnd;

        // -------------------------------------------------------------------------
        public reset(balancer: number): void {

            let lbound = Math.ceil(balancer / 2);
            this._lbound = -lbound;
            this._ubound = balancer - lbound;

            this._currentBalance = balancer === 0 ? this._rnd.integerInRange(-1, 0) : 0;

        // -------------------------------------------------------------------------
        public getBoolean(): boolean {

            let result = this._currentBalance + this._rnd.integerInRange(this._lbound, this._ubound);

            //console.log("lbound = " + (this._lbound + this._currentBalance) + ", ubound = " + (this._ubound + this._currentBalance) +
            //    ", currentBalance = " + this._currentBalance + ", value = " + (result >= 0));

            this._currentBalance += result >= 0 ? -1 : 1;

            return result >= 0;

 In constructor it takes random numbers generator and "magic number" called balancer. This number is your request, how many consecutive same values it shall return when you repeatedly call getBoolean() method.

 For example, if you want true or false maximally two times after each other, then set it to 2.

 reset() method allows you to change this request during runtime.


 Let's do some tests. Our test code will be simple loop with 50 iterations - it just prints string with 50 comma separated results, where true / false is converted to 1 / 0 to shorten output. We will start with balancer value equal 1:

            let randomBalancer = new Helper.RandomBooleanBalancer(this.rnd, 1);
            let result = "";
            for (let i = 0; i < 50; i++) {
                result += (randomBalancer.getBoolean() ? "1" : "0") + (i < 50 - 1 ? ", " : "");

 Here is output from console:

0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1

 As our request was to have maximally 1 consecutive true or false, we got them switching regularly. If you run this test multiple times, you will notice, that whole sequence starts randomly with true or false.

 Now, change number in constructor to 2 and run the test again. This is console output:

0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1

 As you can see, returned values are random, but you get maximally two randoms of the same value after each other.

 Now, change requested value in constructor to 5. You may get something like this:

1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 0, 1, 0, 1, 0, 1, 1, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 1, 1, 0, 0, 1, 1, 1, 0, 1, 0, 0, 1, 1, 1, 0, 0, 0

 In my run I did not get any sequence of 5 ones or zeroes. This is another nice feature of this class. As you get more and more, let's say, ones, there is decreasing probability, that next random will be also one. It is more and more probable it will be zero. But of course, it is possible to get true or false 5 times in row - but this is cap, as you requested: "5 times true or false in row, but no more".


 I hope this small code snippet will make your life easier. If you are interested in how it works, you can uncomment debug output in getBoolean() method and watch it after each call.

Mobile Income Report #30 - December 2016

previous parts
  Mobile Income Report #29 - November 2016
  Mobile Income Report #28 - October 2016
  Mobile Income Report #27 - September 2016
  Mobile Income Report #26 - August 2016 
  Mobile Income Report #25 - July 2016
  Mobile Income Report #24 - June 2016
  Mobile Income Report #23 - May 2016
  Mobile Income Report #22 - April 2016
  Mobile Income Report #21 - March 2016
  Mobile Income Report #20 - February 2016
  Mobile Income Report #19 - January 2016
  Mobile Income Report #18 - December 2015

  Mobile Income Report #1 - June 2014
  Apps page - Portfolio (what are my assets?)

 If you do not want to miss any of my Income Reports you can follow me on Twitter. Just click the button above.

 Under Apps page you can see my portfolio. It is list of the games that are then reported in Income Reports.

What I did in December

  • as usual, I was working on client projects. One of them, one-button game Little Plane, was already published at Gamee

  • worked on both Unity and HTML5 version of our match-3 game Pirates! 58 of 62 levels in world 1 are finished and we are doing finishing touches like adding more particle effects. Our friend Juraj from SoundRose studio made music tracks for game and is now working on sound effects.

Create procedural endless runner in Phaser with TypeScript


 As already announced in November, this is last income report. I decided to end it, because it started as income report from mobile games, but it is more and more about HTML5 games as income from mobile ones is still pretty low. Picking such a small figures from many internet consoles is boring and time consuming. I decided to invest saved time into writing more tutorials and technical articles.

 Figures for December are here:

  There is again decrease compared to November ($107,3). But, as I already said in past, I did nothing with this my mobile portfolio for very long time. I hope this will change in 2017 as I plan to focus more on Unity and spread my time between it and Phaser.
 Most of the income is still from ad in Shards - the brickbreaker game.

 Income from HTML5 hired work and HTML5 licences for December is $1 968,3.

 Income from my book for December is $252,6.

 Total income for December is $2 303,0. It is 28,9% increase, compared to November ($1 787,0).


 In January I am still working on some games for clients and continue with levels and finishing touches for first world of Pirates! I am also taking some Unity video courses I purchased on Udemy.