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Slight improvements to text

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alpine9000
2016-03-27 12:06:45 +11:00
parent 10047f6043
commit cd9f89098f
8 changed files with 131 additions and 131 deletions
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024.simple_text/blittext.s
+75 -102
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@@ -1,53 +1,89 @@
include "includes.i"
xdef DrawText
xdef DrawText8
;; BLTCON? configuration
;; http://amigadev.elowar.com/read/ADCD_2.1/Hardware_Manual_guide/node011C.html
;; blitter logic function minterm truth table
;; fill in D column for desired function
;; A(mask) B(bob) C(bg) D(dest)
;; - - - -
;; 0 0 0 0
;; 0 0 1 1
;; 0 1 0 0
;; 0 1 1 1
;; 1 0 0 0
;; 1 0 1 0
;; 1 1 0 1
;; 1 1 1 1
;; read D column from bottom up = 11001010 = $ca
;; this is used in the LF? bits
BLIT_LF_MINTERM equ $ca
BLIT_DEST equ $100
BLIT_SRCC equ $200
BLIT_SRCB equ $400
BLIT_SRCA equ $800
BLIT_ASHIFTSHIFT equ 12 ;Bit index of ASH? bits
BLIT_BOB_WIDTH equ 32 ; Must blit extra word to allow shifting
BLIT_BOB_HEIGHT equ 10
BLIT_BOB_WIDTH_BYTES equ BLIT_BOB_WIDTH/8
BLIT_BOB_WIDTH_WORDS equ BLIT_BOB_WIDTH/16
;; This will only work for 8 pixel wide fonts
BLIT_LF_MINTERM equ $ca ; cookie cut
BLIT_WIDTH_WORDS equ 2 ; blit 2 words to allow shifting
BLIT_WIDTH_BYTES equ 4
;; BlitText
DrawText8:
;; a0 - bitplane
;; a1 - text
;; d0 - xpos
;; d1 - ypos
movem.l d0/d2/a1,-(sp)
;; blitter config that is shared for every character
move.w #SCREEN_WIDTH_BYTES-BLIT_WIDTH_BYTES,BLTAMOD(a6) ;A modulo
move.w #SCREEN_WIDTH_BYTES-BLIT_WIDTH_BYTES,BLTBMOD(a6) ;B modulo
move.w #SCREEN_WIDTH_BYTES-BLIT_WIDTH_BYTES,BLTCMOD(a6) ;C modulo
move.w #SCREEN_WIDTH_BYTES-BLIT_WIDTH_BYTES,BLTDMOD(a6) ;D modulo
.loop:
move.b (a1)+,d2 ; get next character
cmp.b #0,d2 ; 0 terminates the string
beq .done
jsr DrawChar8 ; draw it
add.w #FONT_WIDTH,d0 ; increment the x position
bra .loop
.done:
movem.l (sp)+,d0/d2/a1
rts
DrawChar8:
;; d0 - xpos
;; d1 - ypos
;; d3 - odd character
;; d2 - char
;; a0 - bitplane
movem.l d0-d5/a0-a2,-(sp)
move.w #'!',d4 ; fontmap offset
sub.w d4,d2 ; index = char - '!'
move.w d2,d5
lsr.w #5,d5 ; fontmap y offset
move.w d5,d4
lsl.w #5,d4 ; start of line
sub.w d4,d2 ;
add.w #1,d5 ; while we have a weird font image, '!' starts on second line
lea font,a1
lea fontMask,a2
mulu.w #SCREEN_WIDTH_BYTES*SCREEN_BIT_DEPTH*FONT_HEIGHT,d5
add.w d5,a2
add.w d5,a1
btst #0,d2 ; blitter does words only, so we need to know if its an odd or even character
beq .even ; then shift it into position with the blitter shift
.odd:
move.b #1,d3
bra .c1
.even:
move.b #0,d3
.c1
add.w d2,a1
add.w d2,a2
jsr BlitChar8
movem.l (sp)+,d0-d5/a0-a2
rts
BlitChar8:
;; kills a0,d0,d3
;; d0 - xpos
;; d1 - ypos
;; d3 - odd character = 1, even character = 0
;; a0 - display
;; a1 - object
;; a2 - mask
BlitText:
movem.l d0-a6,-(sp)
;; a2 - mask
jsr WaitBlitter
;; d0 = XPOS
;; d1 = YPOS
;; d3 = odd character
;; d4 = XPOS_BYTES
move.w d0,d4 ; d4 = XPOS
move.l d0,d4 ; d4 = XPOS
lsr.w #3,d4 ; d4 = XPOS_BYTES
cmp.b #1,d3
@@ -56,7 +92,7 @@ BlitText:
sub.w #8,d0
move.w #$00FF,BLTAFWM(a6) ; no mask for first word
move.w #$0000,BLTALWM(a6) ; mask out last word
sub.l #1,a0
subq #1,a0
bra .continue
.evenChar:
move.w #$ff00,BLTAFWM(a6) ; no mask for first word
@@ -71,13 +107,6 @@ BlitText:
ori.w #BLIT_SRCA|BLIT_SRCB|BLIT_SRCC|BLIT_DEST|BLIT_LF_MINTERM,d0
move.w d0,BLTCON0(A6)
move.w #SCREEN_WIDTH_BYTES-BLIT_BOB_WIDTH_BYTES,BLTAMOD(a6) ;A modulo
move.w #SCREEN_WIDTH_BYTES-BLIT_BOB_WIDTH_BYTES,BLTBMOD(a6) ;B modulo
move.w #SCREEN_WIDTH_BYTES-BLIT_BOB_WIDTH_BYTES,BLTCMOD(a6) ;C modulo
move.w #SCREEN_WIDTH_BYTES-BLIT_BOB_WIDTH_BYTES,BLTDMOD(a6) ;D modulo
move.l a2,BLTAPTH(a6) ; mask bitplane
move.l a1,BLTBPTH(a6) ; bob bitplane
@@ -85,69 +114,13 @@ BlitText:
mulu.w d1,d3 ; d3 = YPOS*SCREEN_WIDTH_BYTES*SCREEN_BIT_DEPTH
move.l a0,d0 ; d0 = #bitplanes
add.w d4,d0 ; d0 = #bitplanes+XPOS_BYTES
add.w d3,d0 ; d0 = #bitplanes+XPOS_BYTES+(YPOS*SCREEN_WIDTH_BYTES*SCREEN_BIT_DEPTH)
add.l d4,d0 ; d0 = #bitplanes+XPOS_BYTES
add.l d3,d0 ; d0 = #bitplanes+XPOS_BYTES+(YPOS*SCREEN_WIDTH_BYTES*SCREEN_BIT_DEPTH)
move.l d0,BLTCPTH(a6) ;background top left corner
move.l d0,BLTDPTH(a6) ;destination top left corner
move.w #(BLIT_BOB_HEIGHT*SCREEN_BIT_DEPTH)<<6|(BLIT_BOB_WIDTH_WORDS),BLTSIZE(a6) ;rectangle size, starts blit
movem.l (sp)+,d0-a6
rts
DrawText:
;; a0 - bitplane
;; a1 - text
;; d0 - xpos
;; d1 - ypos
.loop:
clr.l d2
move.b (a1)+,d2
cmp.b #0,d2
beq .done
jsr DrawChar
add.l #FONT_WIDTH,d0
bra .loop
.done:
rts
DrawChar:
;; d0 - xpos
;; d1 - ypos
;; d2 - char
;; a0 - bitplane
movem.l d0-a6,-(sp)
move.l #'!',d4 ; fontmap offset
sub.l d4,d2 ; index = char - '!'
move.l d2,d5
lsr.l #5,d5 ; fontmap y offset
move.l d5,d4
lsl.l #5,d4 ; start of line
sub.l d4,d2 ;
add.l #1,d5 ; temp marker first line xx
lea font,a1
lea fontMask,a2
mulu.w #SCREEN_WIDTH_BYTES*SCREEN_BIT_DEPTH*BLIT_BOB_HEIGHT,d5
add.l d5,a2
add.l d5,a1
btst.l #0,d2
beq .even
.odd:
move.b #1,d3
bra .c1
.even:
move.b #0,d3
.c1
add.l d2,a1
add.l d2,a2
jsr BlitText
movem.l (sp)+,d0-a6
move.w #(FONT_HEIGHT*SCREEN_BIT_DEPTH)<<6|(BLIT_WIDTH_WORDS),BLTSIZE(a6) ;rectangle size, starts blit
rts
font: