Apple Graphics and Arcade Game Design for Apple II.

A programmer s ability to create Apple graphics can be compared to an artist’s ability with a sketchpad or an animator’s skill with animation. Each in their own way creates images that are in some way entertaining. The viewer, however, is only interested in the final effect, not the tedious technical process that the artist or programmer had to apply to produce that effect. The Apple II is a wonderful graphics tool, but unfortunately highly complex to use at any level other than Applesoft BASIC. The scattered magazine articles covering Apple graphics have shown the machine’s complexity without
presenting an adequate solution to the problem of graphics programming concepts. Those who understand the process and have mastered it are too busy writing programs to share their knowledge.
Magical references like “Raster Graphics” and “Bit Mapping” are spoken of as if they are secret techniques practiced only by the top programmers. Their games, such as “Raster Blaster”, “Galaxian”, “Sneakers”, and “PacMan” have both awed wishful game designers and shown them the limitations of their own programming techniques.
This book will allow you to enter the world of Apple graphics, in which your most imaginative ideas can be animated. The various chapters will attempt to present a comprehensive course in Hi-Res graphics and high speed arcade animation. The major part of this material requires the ability to do assembly language programming.

INTRODUCTION — 6
CHAPTER 1 APPLESOFT HI-RES — 9
1. Description and Screen Layout
2. Screen Switches and Control
3. Memory Considerations
4. Colors and Background Fill 5. Page Flipping
6. Apple Shape Tables
A: Designing Shapes
B: Assembling a Directory
7. Graphic Animation Using Shape Tables
8. Character Generators
CHAPTER 2 LO-RES GRAPHICS — 35
1. Introduction
2. Basic Assembly Language
3. Lo-Res Screen Architecture
4. Plotting Dots and Lines
5. Designing the “Breakout Game”
CHAPTER 3 MACHINE LANGUAGE ACCESS TO APPLESOFT
HI-RES ROUTINES — 69
1. Description and ROM Addresses
2. HPLOT Shapes and Animation
3. Apple Shape Tables in Animation
CHAPTER 4 HI-RES SCREEN ARCHITECTURE — 87
1. Screen Design and Layout
2. Raster Graphics (Bit Mapped) Shape Tables
A: Pros and Cons

B: Forming Bit Mapped Shape Tables
C: Shifted Tables for Precise Positioning
D: Color Problems
CHAPTER 5 BIT MAPPED GRAPHICS — 111
1. Drawing Bit Map Shapes to the Hires Screen
2. Color Problems with Horizontal Movement
3. Screen Erase
4. Selective Drawing Control & Drawing Movement Advantages
5. Interfacing Drawing Routines to Applesoft
CHAPTER 6 ARCADE GRAPHICS — 147
1. Introduction
2. Paddle Routines
3. Dropping Bombs and Shooting Bullets
4. The Invaders Type Game
5. Steerable Space Games
6. Steerable and Free Floating Space Ships
7. Debug Package
8. Laser Fire & Paddle Button Triggers
9. Collisions
10. Explosions
1 1 . Scorekeeping
12. Page Flipping
CHAPTER 7 GAMES THAT SCROLL — 237
1. Games That Scroll
2. Hi-Res Screen Scrolling
A: Vertical Scrolling
B: Horizontal Scrolling
CHAPTER 8 WHAT MAKES A GOOD GAME — 281
1. What Makes A Good Game
2. Successful Game Examples