It's really cool to design all those NOR gates using thermionic valves, as shown in the schematics in the middle of the article. I just wonder if using two regular diodes in the input paths of each NOR gate and another diode in the output path is a little bit of "cheating", since diodes are somewhat newer technology than thermionic valves.
I wonder if he really was afraid of the government, or if he was just tried to keep his brother from loading the games.
The part where he actually cuts the physical tape is great.
The funny thing is that, without cutting the tape, anybody can load the games any way, just like this:
Rewind the tape. LOAD the first program (i.e. the password program). Note that the tape is positioned after the password program now. Reset the C64. Enter LOAD to load the actual game.
Everything the C64 demo scene produces is cataloged and archived at https://csdb.dk/
You can find the latest releases here: https://csdb.dk/latestreleases.php - The C64 demo scene is still very active. There are nearly 40 releases from the last 4 days.
Yes, it is very rewarding to program your own graphics routines or your own simple implementation of a raytracer and then see the correctly rendered scene on screen for the first time.
It's so cool: A scene that took 10 minutes to render in 1995 - nowadays you can see that scene through a moving camera raytraced in real time in your browser!
On 6502, JMP uses 3 cycles. A branch uses 3 cycles if no page boundary is crossed, and 4 cycles if a page boundary is crossed. So there, JMP is "faster".
Nice one! Converting Binary to Hexadecimals is easy when you've got experience from coding assembler on your Commodore 64.
Just remember the 4 bits for each hexadecimal digit. Then enter the 4 bits of the first digit with your left hand and the 4 bits of the seconds digit with your right hand.
In Commodore BASIC, the PRINT command is tokenized and stored as a single byte $99 - see this wiki: http://www.c64-wiki.com/index.php?title=BASIC_token
When you use "?", this gets stored as the same token $99 as well. When you LIST the program then, you see PRINT.
Very nice! There's also a JavaScript remake of the classic C64 game "Boulder Dash" by the same author: http://boulderdash.krissz.hu/
It even comes with a Construction Kit.
Real time ray tracing is also my dream since 1994. I'm very glad that IQ launched ShaderToy.com recently. That inspired me to give real time ray tracing another try, and I'm really happy that you can trace 1000 mirrored spheres in real time today. Have a look here: https://www.shadertoy.com/view/lds3z8