Set magical flag IWDII

[Callirgos]

Hi. I'm trying to set the flag on an item to magical. I'm pretty comfortable patching other things like weight, cost, and abilities, but I can't find an example for the flags

 

00HELMBH

00HFHMBH

 

do not have the "magical" flags set for them

[Mike1072]

The item flags are a 4-byte bitfield at offset 0x18 in the file. The IESDP lists which bits corresponds to which flags here. In the table, Byte 1 is the byte at 0x18, Byte 2 is the byte at 0x19, Byte 3 is the byte at 0x1a, and Byte 4 is the byte at 0x1b. The magical flag is bit 6 of Byte 1, so we only need to worry about that byte.

 

What we want to do is read the byte at 0x18 and set bit 6 to true (1) while leaving its other bits as they are. This is best accomplished using a bitwise operation. A bitwise OR can be used to set specific bits to true (1), while a bitwise AND can be used to set specific bits to false (0). To set bit 6 to true, we will perform a bitwise OR operation using the binary value 01000000 (bits are numbered from the right side starting at 0). This will set bit 6 to 1 and not change any other bits.

 

Using WeiDU TP2 code, we can read the byte, change a single bit, and write the byte using separate commands like this:

READ_BYTE 0x18 flags1 // read first byte of flags
SET flags1 = flags1 | 0b01000000 // set bit 6 (magical flag) to true
WRITE_BYTE 0x18 flags1 // write updated value to file

 

Or we can condense those steps into a single line of code:

WRITE_BYTE 0x18 (THIS | 0b01000000) // set magical flag to true

 

In WeiDU TP2 code, THIS is a substitute for the current value in the file, | is the bitwise OR operator, and 0b01000000 is the binary value 01000000.

[Callirgos]

Thank you for this great explanation!