posprintf#

posprintf - a condensed version of sprintf for Thumb, esp. GBA

https://www.danposluns.com/gbadev/posprintf

By Dan Posluns, released into the public domain.

Warning

This routine is unsafe, make sure the destination buffer is big enough to hold the output string!

Example:

import natu/[video, irq, bios, tte, posprintf]

let friends = 12
let maxFriends = 50

# write formatted text into a buffer
var buffer: array[100, char]
posprintf(addr buffer, "You found %d out of %d friends.", friends, maxFriends)

# draw the text on background 0
tte.initChr4c(bgnr = 0, initBgCnt(cbb = 0, sbb = 31))
tte.write(addr buffer)

# show background 0
dispcnt = initDispCnt(bg0 = true)

# wait forever:
irq.enable(iiVBlank)
while true:
  VBlankIntrWait()

proc posprintf(dest: cstring, src: cstring)#

src must be a valid zero-terminated C string.
dest must point to a sufficiently large block of memory to contain the result string.

The following format specifiers are valid: ======= ========================================================================= %% print a % symbol %s print a string; parameter must point to a valid zero-terminated C string %d print a 16-bit (short) integer; must be within -65,535 .. 65,535 %l print a 29-bit integer; approximate range -500,000,000 .. 500,000,000 %x print a hexadecimal number (lowercase digits) %X print a hexadecimal number (uppercase digits) ======= =========================================================================

The specifiers %d, %l, %x and %X may be modified as follows:

Digits 1 through 9 indicate number of leading spaces to print, eg. | %5d would print the number 123 as " 123" | %5d would print the number 123456 as "123456" (no leading spaces)
When above digit is prefixed with 0, leading zeros are printed instead of spaces | %05d would print the number 123 as "00123" | %04d would print the number 12345 as "12345" (no leading zeros)
Negative sign consumes a leading space, eg. | %05d would print the number -123 as "-0123" | (Hexadecimal numbers are considered unsigned)