By default, Django creates integer primary keys (32 bits) when used with PostgreSQL database. These fields are incremented automatically and work perfectly well in a local environment. A problem that appears when you create an API is the fact that sequential and numeric IDs expose details of your database.

Imagine your client has ID 1; they can imagine (and rightly so) that it’s their first client. The same can be used by competitors to know how many new clients you’ve obtained in a certain period, just by creating a new account. This may generate an uncontrollable desire in some people to explore the values of your keys.

By default, Django creates integer primary keys (32 bits) when used with PostgreSQL database. These fields are incremented automatically and work perfectly well in a local environment. A problem that appears when you create an API is the fact that sequential and numeric IDs expose details of your database.

Imagine your client has ID 1; they can imagine (and rightly so) that it’s their first client. The same can be used by competitors to know how many new clients you’ve obtained in a certain period, just by creating a new account. This may generate an uncontrollable desire in some people to explore the values of your keys.

In this third part, we have the following objectives:

• Clean up the classes
• Multiple planes
• Multiple shots.
• Generalize the game objects into a superclass
• Display a score
• Assign keys to shoot and play again or exit

In the version of Part II, the classes have a lot of repeated code. By analyzing each of them, we can reach a conclusion about a common behavior regarding how to draw and update the objects. A method to remove the object from the game is also used.

In this third part, we have the following objectives:

• Clean up the classes
• Multiple planes
• Multiple shots.
• Generalize the game objects into a superclass
• Display a score
• Assign keys to shoot and play again or exit

In the version of Part II, the classes have a lot of repeated code. By analyzing each of them, we can reach a conclusion about a common behavior regarding how to draw and update the objects. A method to remove the object from the game is also used.

In this second post, we’re going to improve our game.

Although the new version runs in Python, it still looks like an old 80s game. The first thing to fix is the animation. Since we’re using a 280 by 192 point coordinate system to simulate Apple coordinates, we multiply each coordinate by 4 when drawing. To make it look similar to the original Apple, I reduced the number of frames to 8 per second. That’s why the animation looks so jerky! To get it running at 60 frames, we need to multiply the velocities by the ratio between the old and new frame numbers: 8/60. The new version defines some constants for this:

In this second post, we’re going to improve our game.

Although the new version runs in Python, it still looks like an old 80s game. The first thing to fix is the animation. Since we’re using a 280 by 192 point coordinate system to simulate Apple coordinates, we multiply each coordinate by 4 when drawing. To make it look similar to the original Apple, I reduced the number of frames to 8 per second. That’s why the animation looks so jerky! To get it running at 60 frames, we need to multiply the velocities by the ratio between the old and new frame numbers: 8/60. The new version defines some constants for this:

The nostalgia of 80s computers is something I have never stopped feeling. As a child, I was fortunate to use several 8-bit computers, such as the ZX-81, ZX-Spectrum, Apple II, and MSX, or rather, their national clones (TK-85, TK-90X, TK2000), since Brazil was experiencing the era of the Informatics Market Reserve.

In a time when there was no Internet, we spent our time typing programs. A series of books on game programming was published by the Lutécia publishing house in Brazil, but the original American versions were released by Usborne.

The nostalgia of 80s computers is something I have never stopped feeling. As a child, I was fortunate to use several 8-bit computers, such as the ZX-81, ZX-Spectrum, Apple II, and MSX, or rather, their national clones (TK-85, TK-90X, TK2000), since Brazil was experiencing the era of the Informatics Market Reserve.

In a time when there was no Internet, we spent our time typing programs. A series of books on game programming was published by the Lutécia publishing house in Brazil, but the original American versions were released by Usborne.

It’s time to write about a more complete project. I’ll show you the websockets module for Python 3.4, which works very well with asyncio. To avoid interface problems, I decided to write the chat client in JavaScript. The example client was downloaded here. As usual, examples are very simple and leave us wanting more about what we could really do. Who has already tried writing a chat in JavaScript knows that WebSockets are a hand on the wheel.

It’s time to write about a more complete project. I’ll show you the websockets module for Python 3.4, which works very well with asyncio. To avoid interface problems, I decided to write the chat client in JavaScript. The example client was downloaded here. As usual, examples are very simple and leave us wanting more about what we could really do. Who has already tried writing a chat in JavaScript knows that WebSockets are a hand on the wheel.