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Working on the division and multiplication routines.

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git-svn-id: svn://svn.cc65.org/cc65/trunk@4443 b7a2c559-68d2-44c3-8de9-860c34a00d81
This commit is contained in:
uz
2009-11-04 19:41:54 +00:00
parent 655ba3e6ee
commit 18272c0427
11 changed files with 155 additions and 24 deletions
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libsrc/tgi/tgi_clipline.s
+38 -18
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@@ -11,10 +11,12 @@
.export _tgi_clip_dx, _tgi_clip_dy
.export _tgi_xmax, _tgi_ymax
.import negax, pushax, tosmulax, tosdivax
.import negax, pushax
.import imul16x16r32, idiv32by16r16
.import return0, return1
.include "tgi-kernel.inc"
.include "zeropage.inc"
.macpack longbranch
@@ -65,7 +67,7 @@ CLIP_TOP = $08
sbc _tgi_yres+1
bvs L1
eor #$80
L1: bmi L2
L1: bmi L2
ldy #CLIP_NONE ; No clipping actually
@@ -201,17 +203,26 @@ L4: tya
.proc muldiv_dydx
tax
tya ; Move value into a/x
jsr pushax
sty ptr1 ; lhs
sta ptr1+1
lda _tgi_clip_dy
ldx _tgi_clip_dy+1
jsr tosmulax
jsr pushax
ldx _tgi_clip_dy+1 ; rhs
jsr imul16x16r32 ; Multiplicate
; Move the result of the multiplication into ptr1:ptr2
sta ptr1
stx ptr1+1
ldy sreg
sty ptr2
ldy sreg+1
sty ptr2+1
; Load divisor and divide
lda _tgi_clip_dx
ldx _tgi_clip_dx+1
jmp tosdivax
jmp idiv32by16r16
.endproc
@@ -223,17 +234,26 @@ L4: tya
.proc muldiv_dxdy
tax
tya ; Move value into a/x
jsr pushax
sty ptr1 ; lhs
sta ptr1+1
lda _tgi_clip_dx
ldx _tgi_clip_dx+1
jsr tosmulax
jsr pushax
ldx _tgi_clip_dx+1 ; rhs
jsr imul16x16r32 ; Multiplicate
; Move the result of the multiplication into ptr1:ptr2
sta ptr1
stx ptr1+1
ldy sreg
sty ptr2
ldy sreg+1
sty ptr2+1
; Load divisor and divide
lda _tgi_clip_dy
ldx _tgi_clip_dy+1
jmp tosdivax
jmp idiv32by16r16
.endproc