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Simplifying char blit

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alpine9000
2016-04-01 15:58:29 +11:00
parent a79566d429
commit 34bcded682
1 changed files with 13 additions and 17 deletions
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025.scroll_text/blitchar.s
+13 -17
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@@ -19,7 +19,7 @@ BlitChar8:
;; d0 - xpos
;; d1 - ypos
;; d2 - char
movem.l d0-d7/a0-a4,-(sp)
movem.l d0-d5/a0-a2,-(sp)
WaitBlitter
;; blitter config that is shared for every character
@@ -32,24 +32,21 @@ BlitChar8:
mulu.w #BITPLANE_WIDTH_BYTES*SCREEN_BIT_DEPTH,d1 ; ypos bytes
move.w #$ffff,BLTAFWM(a6) ; don't mask first word
move.l #font,a1 ; font pointer
move.l #fontMask,d7 ; font mask pointer
move.w #FONTMAP_WIDTH_BYTES*SCREEN_BIT_DEPTH*FONT_HEIGHT,d3 ; bytes per font line
move.l #fontMask,a2 ; font mask pointer
move.l a0,a4 ; bitplane pointer
bsr DrawChar8 ; draw it
movem.l (sp)+,d0-d7/a0-a4
movem.l (sp)+,d0-d5/a0-a2
rts
DrawChar8:
;; kills d2,d4,d5,a1,a2,a4
;; kills d2,d4,d5,a0,a1,a2
;; d0 - xpos
;; d1 - ypos bytes
;; d2* - char
;; d3 - bytes per font line
;; a4* - bitplane
;; a0 - bitplane
;; a1 - #font
;; d7 - #fontMask
;; a2 - #fontMask
sub.w #'!',d2 ; index = char - '!'
move.w d2,d5
@@ -59,10 +56,9 @@ DrawChar8:
add.l #1,d5 ; while we have a weird font image, '!' starts on second line
mulu.w d3,d5 ; d5 *= #FONTMAP_WIDTH_BYTES*SCREEN_BIT_DEPTH*FONT_HEIGHT
mulu.w #FONTMAP_WIDTH_BYTES*SCREEN_BIT_DEPTH*FONT_HEIGHT,d5 ; d5 *= #FONTMAP_WIDTH_BYTES*SCREEN_BIT_DEPTH*FONT_HEIGHT
if MASKED_FONT==1
move.l d7,a2 ; #fontMask
if MASKED_FONT==1
add.w d5,a2 ; add y offset in lines to fontMask address
endif
@@ -102,13 +98,13 @@ DrawChar8:
move.l a1,BLTBPTH(a6) ; source bitplane
add.l d4,a4 ; dest += XPOS_BYTES
add.l d1,a4 ; dest += YPOS_BYTES
add.l d4,a0 ; dest += XPOS_BYTES
add.l d1,a0 ; dest += YPOS_BYTES
add.l #(FONT_HEIGHT*SCREEN_BIT_DEPTH*BITPLANE_WIDTH_BYTES)-BITPLANE_WIDTH_BYTES+0,a4
add.l #(FONT_HEIGHT*SCREEN_BIT_DEPTH*BITPLANE_WIDTH_BYTES)-BITPLANE_WIDTH_BYTES+0,a0
move.l a4,BLTCPTH(a6) ; background top left corner
move.l a4,BLTDPTH(a6) ; destination top left corner
move.l a0,BLTCPTH(a6) ; background top left corner
move.l a0,BLTDPTH(a6) ; destination top left corner
move.w #(FONT_HEIGHT*SCREEN_BIT_DEPTH)<<6|(BLIT_WIDTH_WORDS),BLTSIZE(a6) ;rectangle size, starts blit
rts