While playing Crimewave for the Saturn recently, it surprised me that the coding for this 
game was done by a single person; Jim Blackler. By doing the regular google search,
I ended up at the website of the Black Cactus studios game Warrior Kings battles.
After an email session it soon became apparent that I was dealing with a very 
experienced SEGA hardware programmer (and a real nice person, I must add) . 
Enjoy this detailed interview!

S.F: Please tell about your past developments, was Crimewave the only title you worked on that was planned for release on a SEGA format? Could you tell us about the other projects? 
(if any)

J.B: I also worked on Prince Of Persia (Megadrive), Bloodshot (Megadrive/Mega CD) and Theme Park (Mega CD). All at Domark software. Bloodshot was my own design, the others 
were conversions.  

S.F: On Prince of persia ; What are the main differences between the Megadrive and 
PC versions?

J.B: Richard Walker the lead programmer rewrote the entire game from scratch. The code was rewritten in 68000, we used the original C as reference. The graphics were mainly retouched versions of the Mac graphics (they had already been enhanced for Mac). The levels were rebuilt by playing the original PC game. I also added some new levels that I designed myself. Other than that they are pretty similar.

S.F: On Bloodshot; Was the game engine written from scratch for Megadrive hardware?

J.B: Yes, the whole thing is written in 68000 entirely by myself.

S.F: Bloodshot is one of the only 3d games for the Megadrive. How powerful was the Megadrive when it came to doing 3D games?

J.B: Not at all. It is a bodge based on the character-based hardware. You had about enough characters to uniquely map about a third of the screen. The ‘polygons’ were inspired by the Wolfenstein 3D approach, they are all made from vertical strips. You might notice that the walls are effectively ‘reflected’ about the centre line using the character map. This is so only half of the walls actually needs to be drawn.  I used a palette effect to disguise the reflection, and sprites for the ceiling light to further hide it. The rasterisation was done with about 750K of pre-generated code in order to reduce the cycle-time per pixel and to draw it all in time. It was quite an innovative effect in my opinion, and as you say it is fairly unique to have 3D on the Megadrive.

S.F: Bloodshot was released in Germany as 'Battle Frenzy' , what was the initial reason for the name change? What are the differences between the two?

J.B: There was a law preventing violent games from being released in Germany , and the distributor thought the name was too violent (!). The problem is there could be only one cartridge image for all territories. You will notice that the language screen comes first – if you select German the game is called Battle Frenzy, and other language Bloodshot. Battle Frenzy was the name in the USA by the way, as there is a comic book by the name of Bloodshot in America .

There are no other differences if I recall correctly.

S.F: What are the main differences between the Megadrive and Mega-CD versions of Bloodshot/Battle Frenzy?

J.B: The first thing is music. The Megadrive version only had ambient sounds, the MegaCD version had an excellent soundtrack by composer Mike Ash. Technically, the Mega CD had much less main RAM than the ROM of the cart, so I had to adapt the game to get it in the lower memory. (You can of course load of the CD but we didn’t have time to do that during the game, plus we were using the CD for the music). I dropped the sample rate of the sound effects for instance. I also redid the levels a bit so that each level was under the target RAM, so there are fewer types of enemy per level. However we were able to include an enemy that we hadn’t had memory to fit on the Megadrive version. The Mega CD had a faster CPU but because I couldn’t have the great big block of pre-generated code I had to go to a slower manual main loop for the renderer, so I think the effect was it was about the same speed.

S.F: Zero Tolerance uses a cable for link up gaming, does Bloodshot support this cable or was it planned? Was there any correspondation between Accolade and you for the use of it?

J.B: Zero Tolerance was of great interest to us during development as that was the only other Megadrive FPS being done that we were aware of. I never saw a link cable or had the SDK. 
I think my view at the time was that split screen mode was better for arcade games.

S.F: On Theme park; What enhancements does the Mega-CD version of Theme park has?

J.B: Music streamed from CD, plus full motion video, plus it’s a bit quicker because of the 
faster CPU.

S.F: What format was used for the added cut scenes in the Mega-CD version of Theme park?

J.B: We used a custom format done for us by developer Interactive Studios, now known as Blitz.

S.F: The Mega-CD had a internal memory function, why wasn't it used for saving? Was the amount of data too large to fit?

J.B: Yes, this was the subject of a heated debate between myself and producers at Acclaim. I would have loved to have used the internal memory for saving but I think I only had about 100K to use and the saves were going to weigh in at several megabytes. Digital compression wasn’t going to be effective enough unfortunately.

S.F: Did you also work on other Megadrive/Mega-CD releases that were cancelled?

J.B: Funnily enough no, I was quite lucky there.


^Just some of the games Jim worked on

S.F: Could you tell a little more about Saturn Crimewave, was it an all new game or a port of 
an earlier version?

J.B: It was an all new game, designed by the team (myself, Joe Groombridge and David Banner) specifically for the Saturn. The reason it was on the Saturn is that the devkits were cheaper so we couldn’t get a PlayStation kit at the time. The idea was to do an isometric type game with 3D hardware. Because the perspective was fixed we could pre-render the cars as sprites (we used 3D Studio). I though that was a neat idea but everyone was doing full 3D then and the isometric view was never all that popular. I really liked driving combat games and large environments which is where the idea for the streaming continuous environment came from. It is fair to say the game didn’t come out the way I liked – the team was too small to do what we wanted. I made a lot of mistakes on the project.

S.F: One of the main criticisms Crimewave got was the low frame rate it ran on. Why was this?
Was it a lack of RAM or main processor speed? Does it use both SH2 processors?

J.B: It’s a fair criticism. I made a bad decision to attempt to stream the graphics from disk without limiting the quantity of graphics in each sector. I worked for months on trying to improve the frame rate but I had tied my own hands on the early decisions. I was really unhappy with the frame rate and the stalling.

S.F: Crimewave sports a two player mode which uses split screen, wouldn't the Saturn link-up
cable be something that could've been used to great extend here?

J.B: It would’ve been, unfortunately the view is it wouldn’t have added enough sales.

S.F: The Japanese copy of Crimewave supports the Arcade racer and Mission stick but wouldn't the analogue pad have been a better option? What are the other notable differences between the different versions?

J.B: I agree, I didn’t get an analog stick to work with until we had finished the game. The reason there is a little bit more in the Japanese version is this one had several months development over the other versions.

^Clockwise from top left:: Prince of Persia (MD/Genesis) , Bloodshot (Mega-CD) , Theme park (Mega-CD) 
and Crimewave (Saturn)

S.F: Crimewave features a screen rotation option; a nod at the days of vertical arcade cabinet screens?

J.B: Absolutely. It was just a silly idea I came up with and implemented, we left it in the game on 
a cheat code for fun.  I wouldn’t recommend having your monitor in its side for too long though, they don’t seem to benefit from it.

S.F: What was working with the Saturn hardware like for you and which equipment was used during Crimewave development?

J.B: I liked the Saturn but it is a hellishly complicated machine to work with, with the dual processors and everything. I didn’t even use the Sega libraries (which was typical of the way I used to program back then). To be fair though it’s probably no more complicated than the PS2 to work with but there was only me working on Crimewave for the most part. The equipment used was one of the original Saturn devkits and SNASM if I recall correctly.

S.F: Any tidbits? Artwork, early screens, missing featuring we should know about?

J.B: There’s nothing hidden in the game other than the cheats which are widely available. Pretty much everything we modeled made it into the game, apart from a train that I couldn’t work out how to program in time. The only thing to mention is the shop fronts in the red light district areas that feature risqué artwork. The artist Joe Groombridge used to see how far we could go before they’d tell us to take it out – and they never did. We did have to take out a confederate flag on 
top of a car for the American release because they thought some people might be offended.

It is worth mentioning that the levels were made by the artist and designer David Banner on an ordinary Saturn using a built in level editor. We used to save to a 128K memory cartridge. I toyed with the idea of leaving that in on a cheat but didn’t.

S.F: Which game (out of all projects on SEGA machines) are you most proud of?

J.B: It would have to be Bloodshot because there was so much innovation in the way it was programmed.

S.F: Tell us about the games have you worked on since Crimewave, such as Warrior Kings: Battles?

J.B: Many thanks for your interest. After Crimewave I designed a game at Eidos but since Crimewave tanked they didn’t want me to do it, so I left and went to Sony where I worked on the original This Is Football (PlayStation), mainly on the physics. I then went to Black Cactus and worked on Warrior Kings. After that I had a spell at Climax on a great game called The Final Option (multi platforms) but the client ran out of money and the game was cancelled.

S.F: What can we expect from Jim Blackler in the future? Any next generation console 
titles planned?

J.B: I’ve been working at Criterion on RenderWare since The Final Option was cancelled. 
I don’t rule out a move back into games in the future.

Many, many thanks to Jim for this interview.
For more information on Warrior Kings: Battles 
visit Http://www.warriorkingsbattles.com