Oh lord. How NOT to do string pointers (6502).

[Gideon Zhi]

Helping out an anon in the IRC channel dig through Legend of the River King for the NES. He was looking for the text; I went a step further and found the pointers. This is pretty funny.

Code Select Expand


$AD18:A2 A6     LDX #$A6
$AD1A:A0 34     LDY #$34
$AD1C:4C DB B0  JMP $B0DB
$AD1F:A2 B3     LDX #$B3
$AD21:A0 40     LDY #$40
$AD23:4C DB B0  JMP $B0DB
$AD26:A2 B3     LDX #$B3
$AD28:A0 55     LDY #$55
$AD2A:4C DB B0  JMP $B0DB
$AD2D:A2 B3     LDX #$B3
$AD2F:A0 6B     LDY #$6B
$AD31:4C DB B0  JMP $B0DB
$AD34:A2 B3     LDX #$B3
$AD36:A0 7B     LDY #$7B
$AD38:4C DB B0  JMP $B0DB
v-- this right here is the pointer for the text belonging to the balding NPC outside the player's home (B38A)
$AD3B:A2 B3     LDX #$B3
$AD3D:A0 8A     LDY #$8A
$AD3F:4C DB B0  JMP $B0DB
$AD42:A2 B3     LDX #$B3
$AD44:A0 9D     LDY #$9D
$AD46:4C DB B0  JMP $B0DB
$AD49:A2 B3     LDX #$B3
$AD4B:A0 AD     LDY #$AD
$AD4D:4C DB B0  JMP $B0DB
$AD50:A2 B3     LDX #$B3
$AD52:A0 C0     LDY #$C0
$AD54:4C DB B0  JMP $B0DB
$AD57:A2 B3     LDX #$B3
$AD59:A0 D5     LDY #$D5
$AD5B:4C DB B0  JMP $B0DB
$AD5E:A2 B3     LDX #$B3
$AD60:A0 EB     LDY #$EB
$AD62:4C DB B0  JMP $B0DB


It goes on like this for several hundred bytes in either direction.

[BRPXQZME]

"All problems in computer science can be solved by another level of indirection."—Wheeler (allegedly)
"... except for the problem of too many layers of indirection."—(also) Wheeler (also allegedly)

[Bregalad]

Mmh, pretty funny. They sure weren't too familiar with the 6502, and/or they used tools to generate such shitty code.

[snarfblam]

I've seen some similar things before, but never on such a magnificent scale. I can only imagine it's the product of a macro or tool, though, and going back and making code prettier doesn't pay the bills, so that's what we get.

[Bregalad]

I've seen some similar things before, but never on such a magnificent scale. I can only imagine it's the product of a macro or tool, though, and going back and making code prettier doesn't pay the bills, so that's what we get.

Making the game fit into a ROM which is one power of two smaller WOULD have saved costs. Now if you are anywhere remote form 2 power of two values for your ROM, wasting or preserving it will have not much effect.

[BRPXQZME]

Maybe they forgot how to fill it with ones and were too embarrassed to ask