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I believe that the original Star Raiders collision detection was done in the core 3D spacial coordinates. The SRII Lasers are done in screen coordinates and I'd have to look at the code to see if I used a simple scale for the target size. I would also want to check the code to see the # of required hits. It has been many years, but I think that the ships were done in a cylindrical space using sines and cosines but using 0-255 degrees. The 3D star field is using a different coordinate system that allows you to rotate a point around the center with a simple addition and then a divide by 256. Using 16 bit values, you get the divide for free by just taking the high byte. This method does deteriorate over time, but I had thought about doing the ships in this format which would have allowed rotations in any dimension. That might have allowed for more realistic movement, but I would have had to find a way to reset the ships on occasion since the rotate is destructive over time. The best way to view this rotate is to go into the long range scan, set your engine speed to 0, and just rotate. If instead of stars, these were the endpoints of the ships, you could do rotations in all 3 dimensions. The file upload system doesn't like spreadsheets soI have attached an image of one I created that shows the rotation. Note the loss of accuracy after the full rotation.

I was at Corp Research and frustrated with the project, Gossip, I was asked to implement so when I finished the work I resigned. Before I left, Chris Horseman, who worked for Lyle Rains in Coin-Op, hired me to implement SRII. Our team started in an office in a warehouse where the games were stored before trucks came in to pick them up. I wish I had a photo since it was not unlike the warehouse at the end of Raiders of the Lost Ark, but with rows of coin-op machines for over a hundred yards. Later we moved into the main Coin-Op building in what I think was Milpitas. While I don't remember Chris Horseman providing significant input on the design of SRII, I remember putting his name before mine on the design document since he was my boss. I believe that Chris' was married to Kim Whitmore. Her background was in optics, and my boss at Corp Research didn't think my implementation of Gossip was correct, so he hired Kim to go through the code and check my math. I heard later that Kim couldn't find any problems with my implementation, just that the design was flawed from the beginning. Re: secret projects, someone described working for a company where the right hand didn't know what the left hand was doing. At Atari, I think it was more the case that the right hand didn't even know that there was a left hand. I didn't work on the 7800, but after the original Ballblazer programmer left Lucasfilm Games, we had a request to build cartridges for what I think was called the 65XE. I was asked to put this together and to the original coder's credit, I don't remember the changes being particularly difficult. Ballblazer was a case of the engineer creating the special effect, and then developing a game to match. The engineer came up with the grid using a specific coding trick on the graphics card. Then he needed a game to put on top, and I heard that other designers were brought in to help. Since the game was so dependent on this graphic trick, implementing Ballblazer on other platforms was really difficult. Re: Tramiels, I was in Coin-Op when I was Riffed. There had been 8,000 employees when I started, and fewer than 500 when I left, so I didn't take it too personally. I only remember meeting with the Tramiel's twice. Once shortly after leaving Coin-Op to get permission to continue working on the game. About a month later I met with them again to show them the progress and to sort out the business side, and it became clear that they weren't going to agree to anything. Shortly after this I found myself invited to meet with the team at Lucasfilm Games. I do believe that at the second meeting they showed me a prototype of the Atari ST.

Please contact TheRedEye.... He currently has the drive. http://atariage.com/forums/topic/246591-wilmunders-star-raiders-ii-released/?p=3389084

I don't remember there being a specific count of the number of pixels since drawing the pixel is just part of the work of the CPU, the other part is determining where to draw it. The decision was based on a judgement of the framerate since this was a real-time simulation. The goal was to support up to 2 ships, the star field, an explosion, and laser fire without slowing significantly. In terms of CPU usage, solid line draws are not too bad, they can be done with integer arithmetic, but the longer the line gets, the more pixels, so the longer the draw takes. I wrote the code to calculate the endpoints and tried solid lines and sure enough when the ships got closer, they slowed down which defeated the goal to have a constant and high frame rate. I needed a plan B. I came up with a different approach that was both fast and easy to implement. I remembered how you could find the midpoint of a line segment by using the Midpoint Formula. This is (x1+x2)/2, (y1+y2)/2. Well the 6502 couldn't do divides, but a binary right-shift will do an integer divide by 2, so with two adds and a shift per dimension, I had the midpoint of my line. Now take that midpoint and one of the endpoints and do it again, and repeat this a few times and you get the dotted lines you see in the ships. Since the number of points don't change, the framerate stays constant. I didn't work on Fractalus directly but when I was at Atari I got to know the teams working on Fractals & Ballblazer and I worked on the fractal code for Koronis Rift. There is another story behind this.... Loren Carpenter was doing the fractal code for the Genesis effect used in the movie Wrath of Kahn. David Fox was working on a game design and they were working in the same building. David admired Loren's work and lamented that the 800 didn't have the CPU to do fractal fly-overs. What David didn't realize was that Loren admired video game programmers because while he was using a bank of computers that might need 24 hours to generate a single video frame, we were using a 6502 and creating a new frame every 30th of a second. While David thought that doing fractals would be impossible, Loren really wanted to try, and a few weeks later they had a demonstration of the code. Loren and David faced a problem that the terrain rendering code worked by drawing vertical stripes so you couldn't rotate the screen. This is why you can only bank your ship a limited amount and even this was done by simply increasing or decreasing the y-position of the points based on their distance from the center of the screen. The screen is actually sheared, not rotated.

Two years ago I spent a day with game archivists including members of this forum and brought the Corvus drive with me. It seemed to spin up just fine, but it didn't boot. We didn't know if the problem was in the controller or even the joystick ports. I did find the warranty card, but I don't think that will help much. I'll leave that project up to people in this forum and I'll work on looking for the printout of the source and floppies. We had talked about releasing the game, I've always been a bit worried since this was work I did for Atari and copyrights are for 70 years. My idea was to do a presentation at the Games Developers Conference on the 3D model used in the original game, and the original game dynamics and then as a finale bring out the sequel.... Attaching the file to an email with Kevin and clicking 'Send' took a lot less effort, though I have to admit that I did hesitate a bit. I have been pretty open about my work on the game and even made a reference to my working on it on my website. I am fortunate to have worked on a long list of top games and so I am usually asked about those projects and not about ones that never shipped. If you add in the release of The Last Starfighter as SRII, and unless you really know your game history, the story is a bit confusing.

Let's see what I can do to answer some of the questions that have come up... On the inverted flight controls for default, I am really glad someone found and posted the additional settings. I struggled with how to make a flight control also a targeting system and I was never fully satisfied with the results. I have also been an RC pilot since I was a teen, and I know when you hear someone yell, "Pull Up!", they are really describing what to do with the stick. You may be able to plug the tablet and paddle controls into the second controller port. I had worked opposite from the team that did the Star Wars arcade game and I got my hands on one of their controls. I replaced the 100Ohm pots with the 10Ohm ones used in the Atari paddle controllers so I could control SRII like the Star Wars arcade. It was fun in the first-person areas, but nearly impossible to control the galactic chart. I've seen a number of comments about making a cartridge. I designed the game so it could be shipped either on floppy or in a cartridge format and I'll explain how. Atari 800 cartridges were limited to 16K. As one poster pointed out, the game image is 22K. Atari had a cartridge in development that had a fixed 8K block of memory and the ability to swap in 1 of 3 other 8K blocks so you were only using 16K at a time. I re-arranged my code to put the common graphics, controls, and sound code in the primary block and the Damage Control screen in another, and I think the planet flyover in another. I burned a set of EPROMS and the cartridge worked great. At one point I was in touch with a journalist who wanted to write a story about SRII and I loaned him the cartridge but never heard from him again. If we can get the Corvus Hard drive with the source code working, making a cartridge might be possible, same with supporting the 5200. I didn't know that the GTIA Damage Control screen wasn't working with PAL. That image was added late in the process and there wasn't time to fix the rectangle that appears around it when the shields are up. There should also be another ship image for machines that didn't have the GTIA chips. Perhaps someone can capture and post that for others to see. I was trying to do some shield effect similar to a scene in the movie Wrath of Kahn. I didn't know that Jack Palevich was at Google. He and I would get together with Landon Dyer when they were working on DigDug while I was at Corp Research. I was a fan of Dandy and I have a copy of the early design document for Gauntlet but it was called 'Dungeons' at the time. Apparently someone who reviewed the document wasn't too fond of the game idea since the copy I have was rubber stamped with a frown face. Jack's wedding gift was a check for the amount of 65 dollars and 2 cents. My wife thought it was odd, but I understood right away. On why this was released now, well there's a bit of a funny story. When I started work on SRII my boss tracked down a copy of the source code for the original Star Raiders. By this point I had already figured out how to do the star field and ships so I put it in the back of my desk. When I left Atari, I dumped my desk into a box that ended up in my garage. At one point Doug Neubauer, the author of SR, posted a photo of the first page of the code and I was able to match the date or version # with my copy so I was pretty sure my source was valid. About 3 weeks ago, I spotted a link to a Github project where a team is trying to recreate the source code for the original Star Raiders. I was excited to see this and assumed that the project was based on Doug Neubauer's copy of the source. Then I saw a scan of the first page and there is a hand-written note that says 'Final Source' that looked like the handwriting on my copy. After I had gotten in touch with Kevin and did the interview and decided to release the disk image for SRII, only then did I learn where the Github source had come from. About 10 years ago I was working on the T-Mobile Sidekick phone. One of my co-workers heard that I had worked for Atari and he brought in his 800 and a floppy drive. I went into my garage and pulled out that box of floppies along with the source code and brought that in to show. Another of my co-workers and I had been friends for many years and he had developed 800 games at Synapse. He saw the source code for Star Raiders and asked if he could make a copy. This was so long ago that I forgot that there was a third copy out there. Now I have to go find that box since if we can't get the Corvus Hard Drive to work, there should be a printout or maybe even a floppy of the source out in the garage. My only concern is that it may not be from an earlier version.