TextFmtRastPortArgs

Synopsis


next = TextFmtRastPortArgs(rp, TextFmt, left, top, flags, ArgList)
D0                         A1  A0       D0    D1   D2     A2

C Prototype


APTR TextFmtRastPortArgs(struct RastPort *rp, STRPTR TextFmt, LONG left, LONG top, LONG flags, APTR args);

Varargs stub:


APTR TextFmtRastPort(struct RastPort *rp, STRPTR TextFmt, LONG left, LONG top, LONG flags, ...);

Description

Prints a C-style formatted string onto a RastPort. This command allows you to use the string formatting style of the standard C printf function. TextFmtRastPortArgs() uses exec.library/RawDoFmt() to format the string; see the exec.library/RawDoFmt() autodocs for details on format specifiers.

The function supports multiline text (using \n as a line separator) and offers text justification options.

Inputs

rp — Pointer to a RastPort structure.
TextFmt — Address of a C-style format string.
left — X coordinate of the text starting position.
top — Y coordinate of the text starting position.
flags — Additional text display parameters:
- ASJ_LEFT — Left-justify the text.
- ASJ_RIGHT — Right-justify the text.
- ASJ_CENTER — Center the text.
- If NULL, ASJ_LEFT is used as the default. In this version, only justification flags are supported.
ArgList — Array of arguments for the format commands.

Result

next — Returns a pointer to the end of the DataStream just processed, allowing the same DataStream to be used for multiple formatting operations using sequential data.

Implementation

The original 68020 assembly implementation:


; (01-Jan-1995) --- TextFmtRastPortArgs(rp,TextFmt,x,y,flgs,ArgList) (a1,a0,d0,d1,d2,a2)
        STRUCTURE ASMTEXT,0
        WORD    atx_Left                ; Passed in INPUTS via D0
        WORD    atx_Top                 ; Passed in INPUTS via D1
        UWORD   atx_Flags               ; Passed in INPUTS via D2
        APTR    atx_TextFmt             ; Text passed in Inputs/Alloc A0
        APTR    atx_DataStream          ; DataStream passed in Inputs via A2
        APTR    atx_RastPort            ; RastPort passed in Inputs via A1
        WORD    atx_MaxWidth            ; Width of the longest string RESULT private
        WORD    atx_MaxHeight           ; Height of all rows RESULT private
        LABEL   atx_SIZEOF
 
TFP_CON addq.w  #1,(a3)                 ; Count characters.. including final zero
        rts
 
TFP_ROU move.b  d0,(a3)+                ; Stuff routine
        rts
 
_LVOTextFmtRastPortArgs
        movem.l d2-d7/a2-a6,-(sp)      ; Save Regs
        lea     -atx_SIZEOF(sp),sp      ; Create the AsmText struct on the Stack...
        move.l  sp,a4                   ; Stack pointed to by A4
        move.l  a6,a5                   ; Save AsmBase
        movem.w d0-d2,atx_Left(a4)     ; Save Left, Top and Flags...
        move.l  a0,atx_TextFmt(a4)     ; Save fmtstring... TextFmt
        move.l  a1,atx_RastPort(a4)    ; Save RastPort
        move.l  a2,atx_DataStream(a4)  ; Save DataStream...
 
; ** TextFmt ** ROUTINE
;
; This part prints text, referencing the ASMTEXT structure
; A4 = ASMTEXT
; A5 = assemblybase
 
TextFmt move.l  ab_ExecBase(a5),a6      ; Exec in A6/Allocate and format
        move.l  atx_TextFmt(a4),a0     ; Text...
        move.l  atx_DataStream(a4),a1  ; DataStream...
        lea     TFP_CON(pc),a2          ; Routine that counts the characters
        pea     0                       ; clear
        move.l  sp,a3                   ; on the stack
        jsr     _LVORawDoFmt(a6)        ; format
        move.l  (sp)+,d0                ; Number of bytes to allocate
        swap    d0                      ; get them
        addq.w  #5,d0                   ; Align + PackAlloc
        bclr    #0,d0                   ; Even
        move.l  d0,d2                   ; Save Len in D2
        moveq   #MEMF_PUBLIC,d1         ; Allocate memory space
        jsr     _LVOAllocMem(a6)
        tst.l   d0                      ; All OK??
        beq     TFP_EXT                 ; Exit failure...
        move.l  d0,a3
        move.l  d2,(a3)+                ; Pack AllocMem A3 = Buffer
        move.l  atx_TextFmt(a4),a0     ; Text...
        move.l  a3,atx_TextFmt(a4)     ; Save the allocated one
        move.l  atx_DataStream(a4),a1  ; DataStream...
        lea     TFP_ROU(pc),a2          ; Create formatted text...
        jsr     _LVORawDoFmt(a6)
        move.l  d0,atx_DataStream(a4)  ; For RESULT...
        move.l  atx_TextFmt(a4),a0     ; Text in A0
 
; At this point, atx_TextFmt contains the formatted text ready to be BUFFERED
; and PRINTED... atx_DataStream holds the pointer to the next data stream...
 
        moveq   #10,d6                  ; NewLine (\n) Character
        move.l  a0,a1
        move.l  sp,d3                   ; ##private - don't delete!!
        pea     0                       ; Reference, for end of list
 
TFP_ZER tst.b   (a0)+                   ; Go to the end of the string...
        bne.s   TFP_ZER
        subq.l  #1,a0                   ; Position on the zero...
        cmp.b   -1(a0),d6              ; NewLine...
        beq.s   TFP_CES                 ; Buffer the next one...
        subq.l  #1,a0                   ; We skip this address...
 
TFP_CES cmp.l   a1,a0                   ; Have we returned to the beginning??
        beq.s   TFP_EBU                 ; Ok, End Buffering...
        cmp.b   -(a0),d6
        bne.s   TFP_CES
        pea     1(a0)
        bra.s   TFP_CES
 
TFP_EBU move.l  a0,-(sp)                ; The last (first) address...
 
; Buffering complete, now on the stack we have as many addresses as there are
; lines, or rather as many NewLine (\n) characters were present, this list ends with a
; LONG = NULL. Now, let's check if any text justification was requested, either
; right or centered. Otherwise there's no issue and we can print directly.
 
        move.l  atx_RastPort(a4),a3    ; RastPort
        move.l  ab_GfxBase(a5),a6      ; The rest is handled by Graphics...
        move.w  atx_Flags(a4),d0       ; Take Flags
        andi.w  #TEXTF_PRIVATE|3,d0    ; Bit 0 and Bit 1/J_RIGHT/J_CENTER
        beq.s   NOJUST                  ; No justification type...
        move.l  sp,a2                   ; Strings to print
        moveq   #0,d5                   ; Width...
        moveq   #0,d2                   ; Height...
 
CAL_LOP move.l  (a2)+,d4                ; String addresses finished???
        beq.s   CAL_EXT                 ; Done...
        move.l  (a2),d7                 ; D7=Next address...
        bne.s   CAL_THE
        move.l  d4,a1
 
CAL_LEN tst.b   (a1)+
        bne.s   CAL_LEN
        move.l  a1,d7
 
CAL_THE sub.w   d4,d7                   ; length in characters
        subq.w  #1,d7                   ; -1 for NewLine (\n)
        move.l  a3,a1
        move.l  d4,a0
        move.w  d7,d0
        jsr     _LVOTextLength(a6)
        add.w   rp_TxHeight(a3),d2     ; Count pixels in Height...
        cmp.w   d0,d5                   ; Which one is larger???
        bge.s   CAL_LOP                 ; D5
        move.w  d0,d5                   ; D0...
        bra.s   CAL_LOP
 
; At this point we haven't actually printed anything, but at least we know
; how wide the longest string is... D5
 
CAL_EXT move.w  d5,atx_MaxWidth(a4)    ; Num. of pixels Width Max
        move.w  d2,atx_MaxHeight(a4)   ; Num. of pixels Height Max
        BTSTW   TEXTB_PRIVATE,atx_Flags(a4)
        bne     TPRIV                   ; Exit - PRIVATE USE ONLY!!!
 
; Now, since we still have our string addresses on the SP, let's go ahead and
; actually print, justifying the text if requested...
 
NOJUST  movem.w atx_Left(a4),d2-d3    ; D2 = Left | D3 = Top
        moveq   #0,d5                   ; No Justification...
 
TFP_LOP move.l  (sp)+,d4                ; String addresses finished???
        beq.s   TFP_FRE
        move.l  (sp),d7                 ; D7=Next address...
        bne.s   TFP_THE
        move.l  d4,a1
 
TFP_LEN tst.b   (a1)+
        bne.s   TFP_LEN
        move.l  a1,d7
 
TFP_THE sub.w   d4,d7                   ; length in characters
        subq.w  #1,d7                   ; -1 for NewLine (\n)
        move.b  atx_Flags+1(a4),d0
        andi.b  #3,d0
        beq.s   NoGiust
        move.l  a3,a1
        move.l  d4,a0
        move.w  d7,d0
        jsr     _LVOTextLength(a6)
        move.w  atx_MaxWidth(a4),d5
        sub.w   d0,d5
        BTSTW   1,atx_Flags(a4)
        beq.s   NoGiust
        asr.w   #1,d5
 
NoGiust move.w  d2,d0                   ; LeftEdge
        add.w   d5,d0                   ; Center...
        movem.w d0/d3,rp_cp_x(a3)     ; SPECIAL MOVE Replace
        ori.w   #RPF_ONE_DOT,rp_Flags(a3)
        move.b  #$F,rp_linpatcnt(a3)
        move.l  a3,a1                   ; RastPort
        move.l  d4,a0                   ; String
        move.w  d7,d0                   ; length
        jsr     _LVOText(a6)
        add.w   rp_TxHeight(a3),d3     ; Next line...
        bra.s   TFP_LOP
 
TFP_FRE move.l  atx_TextFmt(a4),a1
        move.l  -(a1),d0
        move.l  ab_ExecBase(a5),a6
        jsr     _LVOFreeMem(a6)
        move.l  atx_DataStream(a4),d0
        move.l  atx_MaxWidth(a4),d1    ; Private RESULT...
 
TFP_EXT lea     atx_SIZEOF(sp),sp
        movem.l (sp)+,d2-d7/a2-a6
        rts
 
TPRIV   move.l  d3,sp                   ; This part is the exit in case
        move.l  atx_TextFmt(a4),a1    ; private data was requested: A1^TextFmt
        move.l  atx_DataStream(a4),d0  ; D0 = Next DataStream
        move.l  atx_MaxWidth(a4),d1    ; D1 = WidthHeight
        lea     atx_SIZEOF(sp),sp
        movem.l (sp)+,d2-d7/a2-a6
        rts

TextFmtRastPortArgs

Synopsis

C Prototype

Description

Inputs

Result

See Also

Implementation

DOCUMENTATION

RESOURCES

MODULES