Proposal: Add difficulty level select function

[cyblue9]

Hi, @flxbe !

I created difficulty level select function. After intro, It promote for player to select difficulty level.

Change the value of the invaders_shoot_cycles variable according to the selected difficulty level.

example1(easy level):

example2(hard level):

What do you think?

[flxbe]

Very nice feature!

I am only available on my phone for the next days. As soon as I have access to my laptop I will review the PR.

[flxbe]

Do you have any additional feature ideas or comments on the project? During the next days, I will create a few issues for the features I still have in mind.

I am currently pretty occupied with my master's thesis up to December. After this, I could imagine investing a little more time. Do you plan to also spent more time on this project in the future? If so, we should probably talk about a mid-term direction we are both happy with.

[cyblue9]

I love assembly, and I want to write code more! so, I want to spent more time on this project in the future.

I have some feature idea.

• Coding other than x86 assembly
• Recoding of score (time , number of killed invader etc)
• Adding game sound
• Coloring characters etc (reference: https://www.youtube.com/watch?v=MLSSxLe_AFE&)

Other than this project

• Creating other games in assembly (And creating games pack)
• Creating Educational tools of assembly(Because, many young people want to understand assembly but they think that it is difficult to understand assembly in japan(maybe around the world), so Educational tools that to learn by writing code are very useful for them)

Your code is nice and there are many things to learn! Let's do the project for a long time!