SPRITES

BEEBUG GRAPHICS PACKAGE
FOR THE BBC MICRO MODEL B

by Stephen Allen

CONTENTS

1 INTRODUCTION

2 FEATURES OF THE SPRITES PACKAGE

3 GETTING STARTED

4 USER SPRITES

4.1 Overview

4.2 Memory usage

4.3 Initialisation

4.4 Use of variables

4.5 Referencing a sprite

4.6 Drawing a sprite

4.7 Moving a sprite

4.8 Redefining directions

4.9 Deleting a sprite

4.10 Delay routines

4.11 Boundary definitions

5 ADVANCED FEATURES

5.1 Clones

5.2 Animation

5.3 Checking for collisions

5.4 Allocating sprites

5.5 Super sprites

6 DEFINING SPRITES

6.1 Using the definer

6.2 Incorporating User Sprites

7 DEMONSTRATION PROGRAMS

APPENDIX

Programs supplied on cassette

1. INTRODUCTION

The major difference between games written in Basic (or other high level languages) and those written in assembly languages is their speed of operation. This is partly due to their graphics handling. In Basic it is simply not possible to plot intricate objects quickly; even the method of plotting user defined graphics on the screen is clumsy since each colour must be plotted separately. The usual result is that Basic games tend to have jerky graphics, or if they are smooth, the game must be kept simple. Sprites provide an easy way of generating smooth multicoloured graphics.

This sprite package contains routines for creating and moving sprites around the screen at will, for creating sprite clones, and super sprites giving enhanced animation facilities. Special routines are included to check if a sprite collides with another, and all routines are accessible from Basic, allowing arcade style games to be written with a minimum of code. The package also contains a set of example programs.

CONTENTS
1	INTRODUCTION
2	FEATURES OF THE SPRITES PACKAGE
3	GETTING STARTED
4	USER SPRITES
	4.1	Overview
	4.2	Memory usage
	4.3	Initialisation
	4.4	Use of variables
	4.5	Referencing a sprite
	4.6	Drawing a sprite
	4.7	Moving a sprite
	4.8	Redefining directions
	4.9	Deleting a sprite
	4.10	Delay routines
	4.11	Boundary definitions
5	ADVANCED FEATURES
	5.1	Clones
	5.2	Animation
	5.3	Checking for collisions
	5.4	Allocating sprites
	5.5	Super sprites
6	DEFINING SPRITES
	6.1	Using the definer
	6.2	Incorporating User Sprites
7	DEMONSTRATION PROGRAMS
APPENDIX
	Programs supplied on cassette

SPRITES

BEEBUG GRAPHICS PACKAGE FOR THE BBC MICRO MODEL B by Stephen Allen

1. INTRODUCTION

BEEBUG GRAPHICS PACKAGE
FOR THE BBC MICRO MODEL B

by Stephen Allen