This index contains every deep dive article on this site, grouped by category. If you want to learn how Elite works under the hood, then this is the section for you.
Dashboard
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- The 3D scanner - The maths behind Elite's famous 3D elliptical scanner
- The dashboard indicators - How the bar-based dashboard indicators display their data
Drawing circles
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- Drawing circles - The routines that draw planets and the hyperspace and docking tunnels
- The ball line heap - How we remember the lines used to draw circles so they can be redrawn
Drawing lines
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- Bresenham's line algorithm - The main line-drawing algorithm used to draw non-horizontal lines
- Line-clipping - Efficiently clipping an extended line to the part that's on-screen
Drawing pixels
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- Drawing colour pixels in mode 5 - Poking screen memory to display colour pixels in the dashboard view
- Drawing monochrome pixels in mode 4 - Poking screen memory to display monochrome pixels in the space view
- Extended screen coordinates - The extended 16-bit screen coordinate system behind the space view
Drawing planets
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- Drawing craters - The algorithms behind the huge craters of planets like Diso
- Drawing meridians and equators - The algorithms behind the meridians and equators of planets like Lave
Drawing ships
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- Back-face culling - How Elite draws solid-looking 3D ships by only drawing visible faces
- Calculating vertex coordinates - Determining whether a ship's vertex is visible or hidden from us
- Drawing explosion clouds - Drawing and storing explosion clouds for ships whose luck runs out...
- Drawing ships - The main routine for drawing 3D wiremesh ships in space
- Ship blueprints - Specifications for all the different types of ship in the universe
Drawing suns
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- Drawing the sun - Drawing and storing the sun, and the systems on the Short-range Chart
Flight
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- Docking checks - The checks that determine whether we are docking... or just crashing
- Flipping axes between space views - Details of how the different space views are implemented
Keyboard
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- The key logger - Supporting concurrent in-flight key presses using a key logger
Main loop
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- Program flow of the main game loop - The sequence of events in the main game loop and the main flight loop
- Scheduling tasks with the main loop counter - How the main loop counter controls what we do and when we do it
- The Elite memory map - A map of memory usage, details of unused memory locations, and notes on BBC Micro and Acorn Atom label names
Market
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- Market item prices and availability - The algorithms behind the generation of each system's cargo market
Maths (Arithmetic)
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- Adding sign-magnitude numbers - Doing basic arithmetic with sign-magnitude numbers
- Calculating square roots - The algorithm behind the square root routine
- Shift-and-add multiplication - The main algorithm behind Elite's many multiplication routines
- Shift-and-subtract division - The main algorithm behind Elite's many division routines
Maths (Geometry)
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- The sine, cosine and arctan tables - The lookup tables used for the planet-drawing trigonometric functions
Moving
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- Orientation vectors - The three vectors that determine a ship's orientation in space
- Pitching and rolling - Applying our pitch and roll to another ship's orientation in space
- Pitching and rolling by a fixed angle - How other ships manage to pitch and roll in space
- Program flow of the ship-moving routine - A breakdown of the routine that moves the entire universe around us
- Rotating the universe - What happens to the rest of the universe when we rotate our ship?
- Tidying orthonormal vectors - Making the orientation vectors orthonormal, and why this matters
Save and load
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- The competition code - All the information that's hidden in the Elite competition code
Screen mode
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- The split-screen mode - Elite's famous split-screen mode, dissected and explained in detail
Stardust
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- Stardust in the front view - The algorithms behind the stardust particles in the front view
- Stardust in the side views - The algorithms behind the stardust particles in the side views
Tactics
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- In the crosshairs - How the game knows whether an enemy is being hit by our laser fire
- Program flow of the tactics routine - How ships and missiles work out attack patterns... or how to run away
Text
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- Printing decimal numbers - How to print big decimal numbers with decimal points and padding
- Printing text tokens - Printing recursive text tokens, two-letter tokens and control codes
Universe
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- Galaxy and system seeds - How system data is extracted from the galaxy and system seeds
- Generating system data - The algorithms behind the procedural generation of system data
- Generating system names - Producing system names from twisted seeds and two-letter tokens
- Ship data blocks - Storing data for each of the ships in the local bubble of universe
- The local bubble of universe - The data structures used to simulate the universe around our ship
- Twisting the system seeds - How the system seeds are twisted to produce entire galaxies of stars
Utility routines
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- Generating random numbers - The algorithm behind Elite's random number generation routines