Programming adventures in VIC-20.

Verb Examine

Examine (EX) is one of the main verbs in any text adventure. It is the main source of information. The player will want to examine everything.

My EXamine subroutine (first) check if player wants to examine an object. In that case, subroutine cheeks if player carry that object and shows its description.

In other case, there is a chain of jumps to evaluate particular conditions. I will talk you about chains in the next section.

Here is a fragment of the code.

  
;---------
Search_CMD
        ; Player is in the garden'
        cmp #LOC_GARDEN
        bne @Next_Search_1

        ; LEaf is hidden
        ldx #LEAF_IND
        jsr Item_is_Hidden
        bne @Next_Search_1

        ; Move LEaf to the garden
        lda loc
        sta obj_status,x

        jsr PrintObjs
        rts

@Next_Search_1
        ; Search symbols in the lounge

        ; Player is in the lounge
        lda loc
        cmp #LOC_LOUNGE
        bne @Next_Search_2

        ; Player had the the dream
        ; Flag 1 is set
        ldy #$1
        jsr read_flag_y
        beq @Next_Search_2 ; es cero

        ; You find the symbols under a carpet
        ; You need the buried key and the magic word
        lda #str_find_symbols
        jsr PRTSTR

        rts