Let's bounce

Saturday 13th August 2011

I am feeling afresh from my 2 week break in Somerset. Now I am ready for some more programming and music composing. On Thursday (Although I didn't mention it in the blog) I have been drawing some test graphics and sprites for the "Horizontal scrolling platform framework" for the 16KB cartridge game for the RGCD competition, which is currently in progress (And I am aiming to get it released down there in November). I also designed a map for the framework. Looks very basic and sort of rubbish graphics, but well, it's not the actual game graphics for Woolly Jumper. As Shaun's working on those :)

Today I felt like doing some more programming on the platform scroll engine. Although on Thursday I did add the new map to the project, I decided to update the scroll engine slightly. It appeared that I was using the KERNAL IRQ vectors, using #$37 as the $01 value. Because this was limited. I decided to switch off the basic KERNAL vectors, by simply changing the value of $01 to #$35 and then I changed all $0314 and $0315 vectors to $fffe and $ffff. I also add pointers to $fffa and $fffb to disable the RESTORE key from crashing the program. As soon as I was happy with the interrupts, I added an extra interrupt in which uses a standard multicolour for the water, and also a different colour scheme for the platforms. I made the default map colour to use a red scheme. Okay, not really bad. :) I tested the scroll and the scroll seems to work well.

There appears to be something missing. Those of which are SPRITES :). I imported the test sprites into the source code, as raw sprites. Then I got the sprites to display on to the screen. Well, just the player sprite for now that is :). Next I worked on the joystick read routine, so that the player can move up/down left or right (no shooting yet). Once I did that, the next job was to program in the self-modifying Sprite to background collision detection. So I check the value of the character sets which were being used for the top of the platform. The basic idea is to test to see if the player touches any part of the upper charset that represents the platform (anywhere on screen). If the player touches it, the sheep will flash until it is off the background.

After testing the routine was working, I programmed some additional routines that will make the sheep jump continuously. So that I could get the jumping slightly more at an accurate level. After a lot of tweaking with the jumping routine, I altered the joystick routine even more and got the player jumping and falling perfectly. Finally I added the moving aliens (Which still require a variety of movements, which will be implemented later on this week.) I also enabled the player to be able to fire bullets as well. After assembly of the framework so far, things are starting to take shape quite nicely. Enjoy the video! :)

16KB Cartridge Game compo - Ideas. Now which should I choose?

26th June 2011

While I feel to have the urge to finish of Super Tau Zeta for Psytronik Software this week (If I finish from work at 4pm on an 8am - 4pm shift). Another game idea has come to my mind. It is also something for the 16KB cart game competition. I attempted a few things when it came to Commodore 64 assembly programming. It all started with moving sprites around and having to dodge them. The crappy "Target-X" series (I actually did do a Target-X 3 in 2001, but it never came to the light - the disk had died on me at the time), the Gravity series, and in 2004-2008, a pure milestone of a shoot 'em up with varied challenges called "Sub Hunter". I also did a couple of psychedelic games, like Sheepoid and Camels in Space, created in the Jeff Minter style mode (Except for the graphics, which used my own sprites and multicoloured all the way through).

There was however one type of game, which I never actually produced, and it is something retro gamers mainly loved in the 8-bit world. We have seen many of those, but this genre does not die out whatsoever. "What is this retro geek, called Richard/TND talking about then?" you may ask. Well, it is the "PLATFORMER". The question is what type of platform game could I write, and how would I come around it?

Well, I could I suppose, do a single screen which uses the Lode Runner style of mode, in which you're a player having to grab dots. Well, this could be quite appealing. Or perhaps I should do a platform game which uses the horizontal scrolling map. Come to thinking about it, I can only scroll 256 chars. Block/Map scrolling is very tricky. Thankfully I can refer to a framework source which was used for the Ultimate Stunt Boat Challenge source code. Or perhaps I could do a simple single screen platform game. Well, I have a few ideas, but I would need to think about what I could implement for the C64 16KB competition. Here are some simple ideas I have come up with - theoretically.

The Death Saw Challenge

An evil scientist has created several rooms, which consist of moving circular saws, which move along the walls, horizontally, vertically or possibly diagonally. Your player must move around the platform maze, climbing up and down ladders having to flick the switches to disable all of the saws. The only problem is that if you flick one particular switch, a saw may stop, but other saws may keep on moving. This would be quite a gory idea, but sounds quite appealing. Later levels could have faster moving saws, and also some trick switches, that will trigger traps.

Sheepoid II - Wooly Jumper

A psychedelic platform game with a slight twist. You are a Sheep which has to get across several levels. The platforms will move at a constant pace, while your sheep is happily bouncing up and down. The player must avoid falling off the edge. Also to make things more interesting, alien ships can fly across the screen in both directions, sapping the player's energy. The sheep can collect laser pods to fight back the aliens.

Put the Kettle On

I remember a classic VIC20 game called "Wacky Waiters" by Imagine software. Now, I'd love to do a C64 conversion, but I had something completely different in mind. It's a funny game idea in the mode of Wacky Waiters, but instead, you are going to one of the kitchens, and then try and serve cups of tea to the customers who are waiting. The only problem is that you have to carefully enter the lifts which are moving up or down. There could be various objects appearing in the background to slow you down, such as banana skins, bottles, etc.

However, I think Wooly Jumper could be the game I may possibly create for this competition. It sounds like a good laugh and ... but you will have to wait and see what gets released near to November time for the RGCD 16kb cart compo :)