Atari Player Missile Graphics

Atari Player Missile Graphics

When I first bought my Atari 65xe computer at the end of 1986 I was astonished to learn about the amazing graphics capability that was accessible in Basic. This article discusses the Atari Player Missile Graphics. Of course at that time I was also learning Basic, but being already accustomed to the Atari 2600, I began to see that I could create even better graphics with my own computer!

Irronically my Atari 65xe could sit directly next to my Atari 2600 and was even that much more powerful. It was an amazing era to live in. At that time 3D graphic models, mobile games, etc. were non-existent. Yet there was this company called Atari that created a game console that had fun games, but the machine I just purchased for a little over $100 could do circles around the Atari 2600.

The Atari 2600 Years

So my segway to this new machine was opening up unbelievable doors, especially when I started learning how to design graphics on the screen. Yet if you are new to the Atari, let’s introduce you to some similar graphic shapes that were common on the Atari 2600.

Let’s evaluate one game I found interesting called Yars Revenge. You control a fly like creature (referred to as a “Yar” and the goal is to infilitrate a barrier to fire a torpedo from the insect’s mouth and destroy what Atari called the evil Quotile. A close examination of the graphic characters in this game would indicate that they were designed with pixels controlled on raster screen displays. So our goal is to explore something Atari calls ‘Player Missile Graphics’ and learn how they operate. 

Atari Graphic Chips

Because the engineers at Atari had implemented a microchip called TIA (Television Interface Adapter), video game players had the ability to control graphic characters on the screen and interact with the environment. Later Atari introduced CTIA and eventually the GTIA chip that managed more missiles with each upgrade. See the hardware article to learn more.   You can also learn more about the raster displays.

My late night obsession with playing the Atari 2600 since my sister and me received it around 1981-1982 (Christmas season) was sending my creativity into overdrive. More or less it was also my complete compulsion to win every game I played, including my neighbor’s cartridges in order to get some type of justification for my sweaty palms and aching hands. This eventually helped me get an idea for creating a game mentally and devising challenges in my inner consciousness. 

Atari Player Missile Graphics

So in this example I am presenting the first Player Missile Graphics program I came across when I began going through the study guides in my Atari 65xe Personal Computer Owner’s Manual. 

After going through a tutorial on printing text/characters, setting controlled timers (FOR/NEXT), sound, and graphics, I eventually arrived on page 81. There I found a type in program called Players and Missiles.

By this time my curiousity was really getting the best of me. I wasn’t the best typist, so I’ll admit it took me around 8 minutes to type in the program listed below. I have added the lines here as text so you can copy them.

When I was done, I saw a large alien graphic character appear on the screen, moving in front of a wall in a smooth motion from left to right. I was blown away by the marvel of a graphic character that I could only move with a joystick when I opted to play my Atari 2600. However, now I was in the driver’s seat! I could instantly send commands in a Basic program and tell the alien which way to move. I would learn later that I could also change the colors, size, and so much more as I began to sink deeper into the strange world of computer programming. An explanation of the program will be added later. For now I just wanted to keep this simple.

10 POKE 764,255:POKE 580,1
20 GRAPHICS 3+16
30 FOR X=16 TO 24:FOR Y=0 TO 23:COLOR
3:PLOT X,Y:NEXT Y:NEXT X
40 MEMTOP=PEEK(741)+256*PEEK(742)-1
50 PMBASE=INT((MEMTOP-1024)/1024)*1024

60 ADJTOP=PMBASE+384
70 POKE 742,INT(ADJTOP/256):POKE 741,A
DJTOP-256*PEEK(742)
80 POKE 54279,PMBASE/256
90 POKE 53277,2
100 POKE 559,34+8
110 P0=PMBASE+512
120 FOR A=P0 TO P0+128:POKE A,0:NEXT A

130 FOR A=P0+60 TO P0+67:READ B:POKE A
,B:NEXT A
140 POKE 53256,3
150 POKE 623,1
160 POKE 704,108
170 POKE 53248,PEEK(20):GOTO 170
180 DATA 60,126,129,153,255,36,66,129

Much later we will be learning how to control the vertical movement of the player missile graphics and add support for joystick movement. Eventually we will also learn how to animate the game characters using string arrays.

Moving the character down the screen requires clearing the bars in the vertical area as the player moves, which is accomplished in a string.

So be sure to bookmark this page for some great upcoming information!

This Post Has 4 Comments

  1. Theron

    Do you have any kind of ideas for writing articles?
    That’s where I always struggle and I simply finish
    up looking vacant display for long time.

    1. smorrowatari

      Find your passion and go with it. It’s actually very simple. When you are writing about something you enjoy, writing will be so easy.

  2. Levi

    Could you tell me what theme are you making use of on your website?
    It looks good.

    1. smorrowatari

      I am using OceanWP. It’s a free theme through WordPress.

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