Rasm Z80 assembler

[Fessor]

IMHO, structs are meant to save you the work of calculating the index numbers and so that you don't always have to remember these index numbers when you want to work with LD (IX+num)/(IY+num).

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struct spritedef
    ptrGFXdata defw
    coordx     defb
    coordy     defb
endstruct

struct spritedef Sprite1

     org 0x4000
     ld ix,Sprite1
     ld a,(ix+spritedef.coordx)
     ld b,(ix+spritedef.coordy)
     ...
     ...
     ret

Sprite1
    defw 0xc000
    defb 20
    defb 10(If I understood the documentary correctly)

With LD a,(ix+spritedef.coordx) you know immediately where you stand instead of ld a,(ix+3).

[roudoudou]

Ok, thanks. I need the offset structure. The naming as object is just a (misleading) coincidence.

 So, object.item3 point to memory position (in this case defb = 1 Byte + defw = 2 Bytes  = #00 + 3)?


Out of curiosity: what is the difference between structure and object declaration you mentioned?

an object is located in memory so calling him will return his absolute address

a structure is only a definition of offset

in fact the structure definition is a hack, it's kindah like

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nocode
org 0
random_structname
.offset1 defb 0
.offset2 defb 0
.offset3 defb 0
code
then random_structname.offset3 will be equal to 2