Math & utilities

Geometry helpers, the console's deterministic RNG and CRC-32 helpers. Math polyfills are listed on the System page.

Conventions on every page: Availability says whether a symbol exists on the console BIOS, the emulator, or both. c8b and C8B are the same table.

Contents#

• Geometry (c8b.geometry)
  • c8b.geometry.rect.new
  • c8b.geometry.rect.fast_intersection
  • c8b.geometry.rect:unpack
  • c8b.geometry.rect:copy
  • c8b.geometry.rect:offset
  • c8b.geometry.rect:offsetBy
  • c8b.geometry.rect:inset
  • c8b.geometry.rect:insetBy
  • c8b.geometry.rect:isEmpty
  • c8b.geometry.rect:containsPoint
  • c8b.geometry.rect:intersects
  • c8b.geometry.rect:intersection
  • c8b.geometry.rect:union
  • c8b.geometry.rect:centerPoint
  • c8b.geometry.point.new
  • c8b.geometry.point:unpack
  • c8b.geometry.point:copy
  • c8b.geometry.point:offset
  • c8b.geometry.point:distanceToPoint
• Deterministic RNG (c8b.rng, console only)
  • c8b.rng.seed
  • c8b.rng.next
  • c8b.rng.nextInt
  • c8b.rng.nextFloat
  • c8b.rng.state
  • c8b.rng.calls
• Low-level bindings (C8B.*)
  • C8B.Util_crc32
  • C8B.Util_crc32Hex
  • C8B.Util_crc32File
  • C8B.Util_crc32FileHex

Geometry (c8b.geometry)#

c8b.geometry.rect.new#

c8b.geometry.rect.new(x, y, width, height) | c8b.geometry.rect(x, y, w, h)

Creates a rect {x, y, width, height}.

• Returns: rect
• Availability: Console (BIOS) and emulator

c8b.geometry.rect.fast_intersection#

c8b.geometry.rect.fast_intersection(ax, ay, aw, ah, bx, by, bw, bh)

Intersection of two rects given as numbers.

• Returns: x, y, width, height
• Availability: Console (BIOS) and emulator

c8b.geometry.rect:unpack#

rect:unpack()

x, y, width, height.

• Availability: Console (BIOS) and emulator

c8b.geometry.rect:copy#

rect:copy()

New rect.

• Availability: Console (BIOS) and emulator

c8b.geometry.rect:offset#

rect:offset(dx, dy)

Moves in place.

• Availability: Console (BIOS) and emulator

c8b.geometry.rect:offsetBy#

rect:offsetBy(dx, dy)

Moved copy.

• Availability: Console (BIOS) and emulator

c8b.geometry.rect:inset#

rect:inset(dx, dy)

Shrinks in place.

• Availability: Console (BIOS) and emulator

c8b.geometry.rect:insetBy#

rect:insetBy(dx, dy)

Shrunk copy.

• Availability: Console (BIOS) and emulator

c8b.geometry.rect:isEmpty#

rect:isEmpty()

Width or height <= 0.

• Availability: Console (BIOS) and emulator

c8b.geometry.rect:containsPoint#

rect:containsPoint(x, y) | (point)

Point inside (right/bottom edges exclusive).

• Availability: Console (BIOS) and emulator

c8b.geometry.rect:intersects#

rect:intersects(r)

Overlap test.

• Availability: Console (BIOS) and emulator

c8b.geometry.rect:intersection#

rect:intersection(r)

Overlap rect (empty rect 0,0,0,0 if none).

• Availability: Console (BIOS) and emulator

c8b.geometry.rect:union#

rect:union(r)

Bounding rect.

• Availability: Console (BIOS) and emulator

c8b.geometry.rect:centerPoint#

rect:centerPoint()

Centre as a point.

• Availability: Console (BIOS) and emulator

c8b.geometry.point.new#

c8b.geometry.point.new(x, y)

Creates a point {x, y}.

• Returns: point
• Availability: Console (BIOS) and emulator

c8b.geometry.point:unpack#

point:unpack()

x, y.

• Availability: Console (BIOS) and emulator

c8b.geometry.point:copy#

point:copy()

New point.

• Availability: Console (BIOS) and emulator

c8b.geometry.point:offset#

point:offset(dx, dy)

Moves in place.

• Availability: Console (BIOS) and emulator

c8b.geometry.point:distanceToPoint#

point:distanceToPoint(p)

Euclidean distance.

• Availability: Console (BIOS) and emulator

Deterministic RNG (c8b.rng, console only)#

c8b.rng.seed#

c8b.rng.seed(n)

Seeds the generator (for lock-step multiplayer).

• Availability: Console (BIOS) only
• Note: Not available in the emulator.

c8b.rng.next#

c8b.rng.next()

Next raw 32-bit value.

• Returns: integer
• Availability: Console (BIOS) only

c8b.rng.nextInt#

c8b.rng.nextInt(min, max)

Integer in [min, max].

• Returns: integer
• Availability: Console (BIOS) only

c8b.rng.nextFloat#

c8b.rng.nextFloat()

Float in [0, 1).

• Returns: number
• Availability: Console (BIOS) only

c8b.rng.state#

c8b.rng.state()

Current state (for sync checks).

• Returns: integer
• Availability: Console (BIOS) only

c8b.rng.calls#

c8b.rng.calls()

Number of values drawn since seeding.

• Returns: integer
• Availability: Console (BIOS) only

Low-level bindings (C8B.*)#

C8B.Util_crc32#

C8B.Util_crc32(data)

CRC-32 of a string.

• Returns: 1 value(s): integer
• Availability: Console (BIOS) and emulator

C8B.Util_crc32Hex#

C8B.Util_crc32Hex(data)

CRC-32 of a string as 8 hex digits.

• Returns: 1 value(s): string
• Availability: Console (BIOS) and emulator

C8B.Util_crc32File#

C8B.Util_crc32File(path)

CRC-32 of a file.

• Returns: 1 value(s): integer
• Availability: Console (BIOS) and emulator

C8B.Util_crc32FileHex#

C8B.Util_crc32FileHex(path)

CRC-32 of a file as hex.

• Returns: 1 value(s): string
• Availability: Console (BIOS) and emulator