A Game Development Blog by Nickolas Marentes for the Tandy Color Computer 3.

      This blog will primarily focus on the creative and technical design aspects I employ to create this game.
      Due to time constraints, I will not be delving into the actual coding details.


Chapter 07 - Player Movements

This chapter covers the player's character movements.

The player's character now walks left and right along the platforms, he can jump over small obstacles, across platform gaps and between moving elevator platforms. He can take a short fall down to another elevator or platform, but too big a fall and he falls to his doom. He even exerts a short grunt sound when he makes a jump and a thump when he lands again.

A downward movement of the joystick swings his arm out to throw an EMF bomb (no actual bomb as yet) and when the doors are operating, an upward movement of the joystick will have him open the door and enter.

I've been testing his movements to ensure all joystick controls are instant and easy to do and adjusting the jump distance to be enough to easily negotiate short gaps between platforms.

Jumping between moving elevators presents an interesting challenge in that the player must take into account that the distance between the 2 points could be getting dynamically closer or further apart depending on the directions of each platform.

I can tweak many settings as I go along but I am quite happy with all of the settings at the moment.

Ground Mechanics

The player's character looks at the surface under the character's feet to determine if he is supported or if he is falling. It doesn't base it on the tile matrix position but uses this method to provide a more realistic representation of the ground that the player's character is walking on.

Your player's character walks on any surface deemed to be solid ground. Solid ground is defined in the game as any byte location containing a solid white of color 15. I have 2 whites defined in the game's palette. Color 3 is also white and used anywhere I wish to display as white but not a walking support surface. The areas of color 15 is used exclusively for walking support surfaces.

The fixed platforms, moving elevators and a few special areas have color 15 that your player can walk on.

The player's character can also fall a short distance and land on a solid surface but too great a fall, and he falls to his doom to the bottom of the screen just as I did in my game Rupert Rythym.

But wait there's more!

The player's character routine went together fairly quickly and so I decided to slip in some extras to squeeze into this chapter.

I decided to add the 1-way moving elevators and animated rollers in Level 1. These elevators don't stop and reverse direction as most of the elevators in the game. These operate more like the elevators on the 2nd level of Donkey Kong. If you don't jump off them in time, you get pushed into the spinning rollers and subsequently fall to your doom. (No blood in this game to keep it child friendly)  :)

But enough of my droning, click on the image below to see a YouTube video of my progress for this chapter.

This video was recorded running under the latest version of the VCC emulator. There is an annoying click after each sound effect. This is a fault with VCC and does not occur when running on a real CoCo3. Ultimately, I want to get the GIME-X upgrade from Ed Snider so that I can record via the S-Video output directly from my CoCo3.

Copyright 2021 by Nickolas Marentes