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r_phase1.gas
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r_phase1.gas
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.long
.dc.l codeend - _ref1_start
_ref1_start::
.gpu
.org $f03100
DIVCONTROL .equ $f0211c
S_LE .ccdef $14 ; PL
U_LE .ccdef $04 ; CC
S_GT .ccdef $18 ; MI
U_GT .ccdef $08 ; CS
S_LT .ccdef $15 ; PL+NE
U_LT .ccdef $05 ; CC+NE
FP .equr r14
scratch .equr r10
scratch2 .equr r11
RETURNVALUE .equr r29
RETURNPOINT .equr r28
MATH_A .equr r27
MATH_B .equr r26
MATH_C .equr r25
MATH_RTS .equr r24
MATH_SIGN .equr r23
alt_swr15 .equr r4
alt_viewx .equr r5
alt_viewy .equr r6
alt_viewangle .equr r7
alt_lastwallcmd .equr r8
alt_nodes .equr r9
alt_subsectors .equr r10
alt_segs .equr r11
.extern _viewx, _viewy, _viewangle
.extern _lastwallcmd
.extern _nodes
.extern _subsectors,_segs
.extern _tantoangle
.extern _viewangletox
.extern _phasetime
.extern _numnodes
.extern _gpucodestart
.extern _samplecount
.extern _ref2_start
;====================
_R_BSP::
;2 dag registers 0 register variables
;localoffset:4 regoffset:4 argoffset:16
;====================
subq #16,FP
;
; load up some constants
;
movei #_viewx,r0
load (r0),r0
movei #_viewy,r1
load (r1),r1
movei #_viewangle,r2
load (r2),r2
movei #_lastwallcmd,r3
load (r3),r3
movei #_nodes,r4
load (r4),r4
movei #_subsectors,r5
load (r5),r5
movei #_segs,r6
load (r6),r6
moveta r0,alt_viewx
moveta r1,alt_viewy
moveta r2,alt_viewangle
moveta r3,alt_lastwallcmd
moveta r4,alt_nodes
moveta r5,alt_subsectors
moveta r6,alt_segs
movei #_solidsegs,r0
movei #-2,r1
store r1,(r0)
movei #_solidsegs+4,r0
movei #-1,r1
store r1,(r0)
movei #_solidsegs+8,r0
movei #160,r1
store r1,(r0)
movei #_solidsegs+8+4,r0
movei #161,r1
store r1,(r0)
movei #_newend,r0
movei #_solidsegs+16,r1
store r1,(r0)
movei #_numnodes,r0
load (r0),r0
subq #1,r0
store r0,(FP) ; arg[]
movei #_R_RenderBSPNode,r0
store r28,(FP+1) ; push ;(RETURNPOINT)
movei #L60,RETURNPOINT
jump T,(r0)
nop ; delay slot
L60:
load (FP+1), RETURNPOINT ; pop
; save local var back out
movei #_lastwallcmd,r3
movefa alt_lastwallcmd,r0
store r0,(r3)
movei #_phasetime+4,r0
movei #_samplecount,r1
load (r1),r1
store r1,(r0)
movei #_gpucodestart,r0
movei #_ref2_start,r1
store r1,(r0)
L53:
jump T,(RETURNPOINT)
addq #16,FP ; delay slot
;=============================================================================
_R_StoreWallRange::
; set sw_start,sw_end as parameters
; only uses R15, but saves and restores it
; destroys r0, r1, and r2
;=============================================================================
sw_start .equr r8
sw_end .equr r9
sw_rw .equr r15
moveta r15,alt_swr15
movefa alt_lastwallcmd,r1
move r1,sw_rw
movei #112,r2
add r2,r1
moveta r1,alt_lastwallcmd ; rw = lastwallcmd++
movei #_curline,r0
load (r0),r0
store r0,(sw_rw) ; rw->seg = curline
store sw_start,(sw_rw+1) ; rw->start = start
movei #_lineangle1,r1
load (r1),r1
store sw_end,(sw_rw+2) ; rw->end = start
store r1,(sw_rw+3) ; rw->angle1 = lineangle1 (delay slot)
jump T,(RETURNPOINT)
movefa alt_swr15,r15
;====================
_R_ClipSolidWallSegment::
;3 dag registers 2 register variables
;localoffset:8 regoffset:8 argoffset:32
;====================
cs_start .equr r14
cs_next .equr r15
cs_first .equr r17
cs_last .equr r18
cs_scratch .equr r19
cs_SWR .equr r20
cs_saved14 .equr r21
cs_savedreturn .equr r22
move RETURNPOINT,r22
load (FP),cs_first
load (FP+1),cs_last
move FP,cs_saved14
movei #_R_StoreWallRange,cs_SWR
; find the first range that touches the range (adjacent pixels are touching)
move cs_first,cs_scratch
subq #1,cs_scratch
movei #_solidsegs,cs_start
findfirst:
load (cs_start+1),r0
cmp r0,cs_scratch
jr S_LT,findfirst
addq #8,cs_start ; delay slot
subq #8,cs_start ; back up
; add visible pieces and close up holes
load (cs_start),r1 ;(start)
cmp cs_first,r1
movei #L65,scratch
jump EQ,(scratch)
nop
jump MI,(scratch)
nop
load (cs_start),r1 ;(start)
subq #1,r1
cmp cs_last,r1
movei #L67,scratch
jump EQ,(scratch)
nop
jump MI,(scratch)
nop
move cs_first,sw_start
move cs_last,sw_end
move PC,RETURNPOINT
jump T,(cs_SWR)
addq #6,RETURNPOINT
movei #_newend,r0
load (r0),r1
move r1,cs_next ;(next)
addq #8,r1
store r1,(r0)
movei #L70,r0
jump T,(r0)
nop
L69:
move cs_next,r0
subq #8,r0
load (r0),r0
store r0,(cs_next) ;(next)
move cs_next,r1 ;(next)
subq #4,r1
load (r1),r1
btst #0,r1 ;scoreboard
store r1,(cs_next+1)
subq #8,cs_next
L70:
cmp cs_next,cs_start
movei #L69,scratch
jump NE,(scratch)
nop
store cs_first,(cs_next) ;(next)
store cs_last,(cs_next+1)
jump T,(cs_savedreturn)
move cs_saved14,FP ; delay slot
L67:
move cs_first,sw_start
load (cs_start),sw_end
subq #1,sw_end
move PC,RETURNPOINT
jump T,(cs_SWR)
addq #6,RETURNPOINT
store cs_first,(cs_start) ;(start)
L65:
load (cs_start+1),r1
cmp cs_last,r1
movei #L72,scratch
jump MI,(scratch)
nop
jump T,(cs_savedreturn)
move cs_saved14,FP ; delay slot
L72:
move cs_start,cs_next ;(start)(next)
movei #L75,r0
jump T,(r0)
nop
L74:
load (cs_next+1),sw_start
addq #1,sw_start
load (cs_next+2),sw_end
subq #1,sw_end
move PC,RETURNPOINT
jump T,(cs_SWR)
addq #6,RETURNPOINT
addq #8,cs_next
load (cs_next+1),r1
cmp cs_last,r1
movei #L77,scratch
jump MI,(scratch)
nop
load (cs_next+1),r0
btst #0,r0
store r0,(cs_start+1)
movei #L79,r0
jump T,(r0)
nop
L77:
L75:
load (cs_next+2),r1
subq #1,r1
cmp cs_last,r1
movei #L74,scratch
jump EQ,(scratch)
nop
jump MI,(scratch)
nop
load (cs_next+1),sw_start
addq #1,sw_start
move cs_last,sw_end ; local last
move PC,RETURNPOINT
jump T,(cs_SWR)
addq #6,RETURNPOINT
store cs_last,(cs_start+1)
L79:
movei #_newend,r4
load (r4),r3
cmp cs_next,cs_start
movei #L83,scratch
jump NE,(scratch)
nop
jump T,(cs_savedreturn)
move cs_saved14,FP ; delay slot
L82:
addq #8,cs_start
load (cs_next),r0
load (cs_next+1),r1
store r0,(cs_start)
store r1,(cs_start+1)
L83:
cmp cs_next,r3
jr NE,L82
addq #8,cs_next ; delay slot
store cs_start,(r4) ; newend
jump T,(cs_savedreturn)
move cs_saved14,FP ; delay slot
;=============================================================================
_R_ClipPassWallSegment::
;2 dag registers 1 register variables
;localoffset:8 regoffset:8 argoffset:24
;=============================================================================
cp_start .equr r15
cp_first .equr r16
cp_last .equr r17
cp_scratch .equr r18
cp_SWR .equr r19
load (FP),cp_first
load (FP+1),cp_last
subq #12,FP
movei #_R_StoreWallRange,cp_SWR
store RETURNPOINT,(FP+2) ; only save once
; find the first range that touches the range (adjacent pixels are touching)
move cp_first,cp_scratch
subq #1,cp_scratch
movei #_solidsegs,cp_start
L90:
load (cp_start+1),r0
cmp r0,cp_scratch
jr S_LT,L90
addq #8,cp_start ; delay slot
subq #8,cp_start ; back up
;
; cut up the seg around solid pieces
;
load (cp_start),r1 ;(start)
cmp cp_first,r1
movei #L93,scratch
jump EQ,(scratch)
nop
jump MI,(scratch)
nop
load (cp_start),r1 ;(start)
subq #1,r1
cmp cp_last,r1
movei #L95,scratch
jump EQ,(scratch)
nop
jump MI,(scratch)
nop
move cp_first,sw_start ; arg[]
move cp_last,sw_end ; arg[]
movei #L89,RETURNPOINT
jump T,(cp_SWR)
nop
L95:
move cp_first,sw_start ; arg[]
load (cp_start),sw_end ;(start)
subq #1,sw_end
move PC,RETURNPOINT
jump T,(cp_SWR)
addq #6,RETURNPOINT
L93:
load (cp_start+1),r1
cmp cp_last,r1
movei #L89,scratch
jump PL,(scratch)
nop
movei #L100,scratch
jump T,(scratch)
nop
L99:
load (cp_start+1),sw_start
addq #1,sw_start
load (cp_start+2),sw_end
subq #1,sw_end
move PC,RETURNPOINT
jump T,(cp_SWR)
addq #6,RETURNPOINT
addq #8,cp_start
load (cp_start+1),r1
cmp cp_last,r1
movei #L89,scratch
jump PL,(scratch)
nop
L100:
load (cp_start+2),r1
subq #1,r1
cmp cp_last,r1
movei #L99,scratch
jump EQ,(scratch)
nop
jump MI,(scratch)
nop
load (cp_start+1),sw_start
addq #1,sw_start
move cp_last,sw_end
movei #L89,RETURNPOINT
jump T,(cp_SWR)
nop
L89:
load (FP+2), RETURNPOINT ; pop
jump T,(RETURNPOINT)
addq #12,FP ; delay slot
;=============================================================================
_R_PointToAngle:
;
; pass pt_basex, pt_basey parms, toasts r0-r4
;=============================================================================
pt_basex .equr r12
pt_basey .equr r13
pt_scratch .equr r0
numerator .equr r1
denominator .equr r2
absx .equr r3
absy .equr r4
ANG90 .equ $40000000
ANG180 .equ $80000000
ANG270 .equ $c0000000
movefa alt_viewx,r0
sub r0,pt_basex
movefa alt_viewy,r0
sub r0,pt_basey
move pt_basex,absx
move pt_basey,absy
abs absx
abs absy
move absx,numerator
move absy,denominator
cmp numerator,denominator
jr CC,noflip ; numerator must be >= denominator
nop
move numerator,r0
move denominator,numerator
move r0,denominator
noflip:
shlq #3,numerator
shrq #8,denominator
div denominator,numerator
movei #2048,scratch
cmp scratch,numerator
jr U_GT,inrange
nop
move scratch,numerator
inrange:
shlq #2,numerator
movei #_tantoangle,r0
add r0,numerator
load (numerator),numerator
movei #xnegative,scratch2
btst #31,pt_basex
jump NE,(scratch2)
nop
;======= x >= 0
btst #31,pt_basey
jr NE,xpyn
nop
cmp absx,absy
jr CC,xpypyg
nop
;xpypxg:
jump T,(RETURNPOINT)
move numerator,RETURNVALUE ; delay slot
xpypyg:
movei #ANG90-1,RETURNVALUE
jump T,(RETURNPOINT)
sub numerator,RETURNVALUE
xpyn:
cmp absx,absy
jr CC,xpynyg
nop
;xpynxg:
move numerator,RETURNVALUE
jump T,(RETURNPOINT)
neg RETURNVALUE
xpynyg:
movei #ANG270,RETURNVALUE
jump T,(RETURNPOINT)
add numerator,RETURNVALUE
;======= x <= 0
xnegative:
btst #31,pt_basey
movei #xnyn,scratch2
jump NE,(scratch2)
nop
cmp absx,absy
jr CC,xnypyg
nop
;xnypxg:
movei #ANG180-1,RETURNVALUE
jump T,(RETURNPOINT)
sub numerator,RETURNVALUE
xnypyg:
movei #ANG90,RETURNVALUE
jump T,(RETURNPOINT)
add numerator,RETURNVALUE
xnyn:
cmp absx,absy
jr CC,xnynyg
nop
;xnynxg:
movei #ANG180,RETURNVALUE
jump T,(RETURNPOINT)
add numerator,RETURNVALUE
xnynyg:
movei #ANG270-1,RETURNVALUE
jump T,(RETURNPOINT)
sub numerator,RETURNVALUE
;============================================================================
_R_RenderBSPNode::
;5 dag registers 2 register variables
;localoffset:4 regoffset:4 argoffset:36
;============================================================================
rb_bsp .equr r15
rb_subsector .equr r15
; if the bspnum has bit 15 set, its a subsector
load (FP),rb_bsp
btst #15,rb_bsp
movei #decisionnode,r0
jump EQ,(r0)
bclr #15,rb_subsector ; harmless delay slot
;===========================
;
; subsector
;
; fp+2: returnpoint (stomps on previous parameter)
; fp+1: stopline
; fp: line (also used as parameter to R_AddLine)
;===========================
store RETURNPOINT,(FP)
subq #8,FP
moveq #12,r0
mult r0,rb_subsector
movefa alt_subsectors,r0
add r0,rb_subsector
movei #_frontsector,r0
load (rb_subsector),r1
store r1,(r0) ; frontsector = subsector->sector
.extern _lastvissubsector
movei #_lastvissubsector,r0
load (r0),r2
store rb_subsector,(r2) ; *lastvissubsector = sub
addq #4,r2
store r2,(r0) ; lastvissubsector++
load (rb_subsector+2),r1
shlq #5,r1
movefa alt_segs,r2
add r2,r1
store r1,(FP) ; line = &segs[sub->firstline]
load (rb_subsector+1),r2 ; count = sub->numlines
shlq #5,r2
add r1,r2
btst #0,r2 ; scoreboard bug
store r2,(FP+1) ; stopline = line+count
nextline:
cmp r1,r2 ; if line == stopline
jr NE,doline
load (FP+2),RETURNPOINT ; harmless delay slot
jump T,(RETURNPOINT)
addq #8,FP ; delay slot
doline:
movei #_R_AddLine,r0
movei #subsecreturn,RETURNPOINT
jump T,(r0)
nop
subsecreturn:
load (FP),r1
addq #16,r1
addq #16,r1
movei #nextline,r0
store r1,(FP) ; line++
jump T,(r0)
load (FP+1),r2 ; r2 = stopline (delay slot)
;===========================
;
; decision node
;
; fp+2: returnpoint (stomps on previous parameter)
; fp+1: bsp
; fp: parameter
;===========================
decisionnode:
store RETURNPOINT,(FP) ; don't need to save again
subq #8,FP
;
; bsp = &nodes[bspnum]
;
movei #56,r0
mult r0,rb_bsp
movefa alt_nodes,r1
add r1,rb_bsp
store rb_bsp,(FP+1) ; don't need to save again
;
; decide which side to render first
;
movefa alt_viewy,r0
load (rb_bsp+1),r1
sub r1,r0
sharq #16,r0 ; r0 = (viewy-bsp->y)>>16
load (rb_bsp+2),r1
sharq #16,r1 ; r1 = bsp->dx>>16
imult r1,r0
movefa alt_viewx,r1
load (rb_bsp),r2
sub r2,r1
sharq #16,r1 ; r1 = (viewx-bsp->x)>>16
load (rb_bsp+3),r2
sharq #16,r2 ; r2 = bsp->dy>>16
imult r2,r1
movei #backside,scratch
cmp r0,r1
jump S_GT,(scratch)
nop
jump EQ,(scratch)
nop
;-----------------
;
; front side first
;
;-----------------
movei #48,r1
add rb_bsp,r1 ; &bsp->children[0]
load (r1),r0
store r0,(FP) ; arg[]
movei #_R_RenderBSPNode,r0
movei #frontdrawn,RETURNPOINT
jump T,(r0)
nop
frontdrawn:
load (FP+1),rb_bsp
movei #32,r0
add rb_bsp,r0 ; &bsp->bbox[1]
store r0,(FP) ; arg[]
movei #_R_CheckBBox,r0
movei #frontcheck,RETURNPOINT
jump T,(r0)
nop
frontcheck:
or RETURNVALUE,RETURNVALUE
movei #exitrbsp,RETURNPOINT
jump EQ,(RETURNPOINT) ; go to exit point
nop
load (FP+1),rb_bsp
movei #52,r1
add rb_bsp,r1 ; &bsp->children[1]
load (r1),r0
store r0,(FP) ; arg[]
movei #_R_RenderBSPNode,r0
jump T,(r0)
nop
;-----------------
;
; back side first
;
;-----------------
backside:
movei #52,r1
add rb_bsp,r1 ; &bsp->children[1]
load (r1),r0
store r0,(FP) ; arg[]
movei #_R_RenderBSPNode,r0
movei #backdrawn,RETURNPOINT
jump T,(r0)
nop
backdrawn:
load (FP+1),rb_bsp
addq #16,rb_bsp ; &bsp->bbox[0]
store rb_bsp,(FP) ; arg[]
movei #_R_CheckBBox,r0
movei #backcheck,RETURNPOINT
jump T,(r0)
nop
backcheck:
or RETURNVALUE,RETURNVALUE
movei #exitrbsp,RETURNPOINT
jump EQ,(RETURNPOINT)
nop
load (FP+1),rb_bsp
movei #48,r1
add rb_bsp,r1 ; &bsp->children[0]
load (r1),r0
store r0,(FP) ; arg[]
movei #_R_RenderBSPNode,r0
jump T,(r0)
nop
;
; done
;
exitrbsp:
load (FP+2), RETURNPOINT ; pop
jump T,(RETURNPOINT)
addq #8,FP ; delay slot
;==============================================================================
_R_AddLine::
;4 dag registers 7 register variables
;localoffset:8 regoffset:8 argoffset:56
;
; fp+4 parm: line
; fp+3 saved angle1
; fp+2 saved returnpoint
; fp+1 arg 2
; fp arg 1
;==============================================================================
CLIPANGLE .equ 537395200
DOUBLECLIPANGLE .equ 1074790400
al_backsector .equr r15
al_angle1 .equr r16
al_angle2 .equr r17
al_tspan .equr r18
al_x1 .equr r19
al_x2 .equr r20
al_span .equr r21
al_clipangle .equr r8
al_doubleclipangle .equr r7
subq #16,FP
nop ; scoreboard bug
store RETURNPOINT,(FP+2) ; only save once
load (FP+4),r1 ; local line
movei #_curline,r0
store r1,(r0) ; curline = line
;
; get angle 1
;
load (r1),r0
load (r0),pt_basex
addq #4,r0
load (r0),pt_basey
movei #_R_PointToAngle,r0
move PC,RETURNPOINT
jump T,(r0)
addq #6,RETURNPOINT
move RETURNVALUE,al_angle1
;
; get angle2
;
load (FP+4),r0 ; local line
addq #4,r0
load (r0),r0
load (r0),pt_basex
addq #4,r0
load (r0),pt_basey
movei #_R_PointToAngle,r0
move PC,RETURNPOINT
jump T,(r0)
addq #6,RETURNPOINT
move RETURNVALUE,al_angle2
;
; clip to view edges
;
move al_angle1,al_span
sub al_angle2,al_span
movei #addlinereturn,r0
jump MI,(r0) ; if span >= ANG180 return
nop
movei #_lineangle1,r0
store al_angle1,(r0)
movefa alt_viewangle,r0
sub r0,al_angle1
sub r0,al_angle2
movei #CLIPANGLE,al_clipangle
movei #DOUBLECLIPANGLE,al_doubleclipangle
move al_angle1,al_tspan
add al_clipangle,al_tspan
cmp al_tspan,al_doubleclipangle
movei #L911,scratch
jump CC,(scratch)
nop
sub al_doubleclipangle,al_tspan
cmp al_tspan,al_span
movei #L913,scratch
jump U_LT,(scratch)
nop
movei #addlinereturn,r0
jump T,(r0)
nop
L913:
move al_clipangle,al_angle1
L911:
move al_clipangle,al_tspan
sub al_angle2,al_tspan
cmp al_tspan,al_doubleclipangle ;(tspan)
movei #L915,scratch
jump CC,(scratch)
nop
sub al_doubleclipangle,al_tspan
cmp al_tspan,al_span ;(tspan)(span)
movei #L917,scratch
jump U_LT,(scratch)
nop
movei #addlinereturn,r0
jump T,(r0)
nop
L917:
move al_clipangle,al_angle2
neg al_angle2
;
; the seg is in the view range, but not necessarily visible
;
L915:
; angle1 = (angle1+ANG90)>>ANGLETOFINESHIFT;
; angle2 = (angle2+ANG90)>>ANGLETOFINESHIFT;
movei #1073741824,r0
add r0,al_angle1
shrq #19,al_angle1
add r0,al_angle2
shrq #19,al_angle2
; x1 = viewangletox[angle1];
; x2 = viewangletox[angle2];
move al_angle1,r1 ;(angle1)
shlq #2,r1
movei #_viewangletox,r2
add r2,r1
load (r1),al_x1
move al_angle2,r1 ;(angle2)
shlq #2,r1
add r2,r1
load (r1),al_x2
; if (x1 == x2) return
cmp al_x1,al_x2 ;(x1)(x2)