mirror of
https://github.com/ClassiCube/ClassiCube.git
synced 2025-01-22 09:01:57 -05:00
196 lines
6.7 KiB
ArmAsm
196 lines
6.7 KiB
ArmAsm
! r1 = v1, CLOBBERS
|
|
! r2 = v2, CLOBBERS
|
|
! r3 = OUT, CLOBBERS
|
|
! r4 = TMP 1, preserved
|
|
! r5 = TMP 2, preserved
|
|
! r0 = CL0, CLOBBERS
|
|
|
|
! FR0 = 0
|
|
! FR1 = 0
|
|
! FR2 = A.1
|
|
! FR3 = B.1
|
|
! FR4 = 0
|
|
! FR5 = 0
|
|
! FR6 = A.2
|
|
! FR7 = B.2
|
|
! FR8 = 0
|
|
! FR9 = 0
|
|
! FR10 = invT
|
|
! FR11 = t
|
|
|
|
#define TM1 r0 // CLOBBERED, temp register 1
|
|
#define TM2 r4 // PRESERVED, temp register 2
|
|
#define CLO r5 // PRESERVED, output colour
|
|
|
|
#define IN1 r1 // CLOBBERED, input vertex 1
|
|
#define IN2 r2 // CLOBBERED, input vertex 2
|
|
#define OUT r3 // CLOBBERED, output vertex
|
|
|
|
#define CL1 r1 // CLOBBERED, input colour 1
|
|
#define CL2 r2 // CLOBBERED, input colour 2
|
|
|
|
! Calculates the near plane intersection point between two points:
|
|
! float t = fabsf(v1->z) / fabsf(v2->z - v1->z)
|
|
! float invt = 1.0f - t;
|
|
!
|
|
! out->x = invt * v1->x + t * v2->x;
|
|
! out->y = invt * v1->y + t * v2->y;
|
|
! out->z = 0.0f; // clipped against near plane anyways (I.e Z/W = 0 --> Z = 0)
|
|
!
|
|
! out->u = invt * v1->u + t * v2->u;
|
|
! out->v = invt * v1->v + t * v2->v;
|
|
! out->w = invt * v1->w + t * v2->w;
|
|
!
|
|
! out->b = invt * v1->b + t * v2->b;
|
|
! out->g = invt * v1->g + t * v2->g;
|
|
! out->r = invt * v1->r + t * v2->r;
|
|
! out->a = invt * v1->a + t * v2->a;
|
|
! To optimise these calculations, FIPR is used:
|
|
! FIPR = FVm.x*FVn.x + FVm.y*FVn.x + FVm.z*FVn.z + FVm.w*FVn.w --> FVn.w
|
|
! FIPR can be used to accomplish "vout->Q = invt * v1->Q + t * v2->Q" by:
|
|
! - assigning x/y components to 0 for both vectors
|
|
! - assigning t and invT to z/w of FVm vector
|
|
! - assigning v1 and v2 to z/w of FVn vector
|
|
! FIPR = 0*0 + 0*0 + t*v1->Q + invT*v2->Q --> FVn.w
|
|
! FIPR = t*v1->Q + invT*v2->Q --> FVn.w
|
|
|
|
.global _ClipLine
|
|
.align 4
|
|
_ClipLine:
|
|
mov.l r4,@-r15 ! LS, push(r4)
|
|
mov.l r5,@-r15 ! LS, push(r5)
|
|
mov IN1, TM1 ! MT, tmp = &v1
|
|
fldi0 fr4 ! LS, fr4 = 0
|
|
add #12, TM1 ! EX, tmp = &v1->z
|
|
fmov.s @TM1, fr2 ! LS, fr2 = v1->z
|
|
mov IN2, TM1 ! MT, tmp = &v2
|
|
fldi0 fr5 ! LS, fr5 = 0
|
|
add #12, TM1 ! EX, tmp = &v2->z
|
|
fmov.s @TM1,fr11 ! LS, fr11 = v2->z
|
|
fsub fr2,fr11 ! FE, fr11 = v2->z - v1->z
|
|
fldi0 fr8 ! LS, fr8 = 0
|
|
fmul fr11,fr11 ! FE, fr11 = (v2->z - v1->z) * (v2->z * v1->z)
|
|
fldi0 fr9 ! LS, fr9 = 0
|
|
fldi0 fr0 ! LS, fr0 = 0
|
|
fldi0 fr1 ! LS, fr1 = 0
|
|
fsrra fr11 ! FE, fr11 = 1 / abs(v2->z - v1->z)
|
|
fabs fr2 ! LS, fr2 = abs(v1->z)
|
|
fmul fr2,fr11 ! FE, fr11 = abs(v1->Z) / abs(v2->z - v1->z) --> t
|
|
add #4, IN1 ! EX, v1 += 4
|
|
fldi1 fr10 ! LS, fr10 = 1
|
|
add #4, IN2 ! EX, v2 += 4
|
|
add #4, OUT ! EX, OUT += 4
|
|
fsub fr11,fr10 ! FE, fr10 = 1.0 - t --> invT
|
|
|
|
fmov.s @IN1+, fr2 ! LS, A1 = v1->x, v1 += 4
|
|
fmov.s @IN2+, fr3 ! LS, B1 = v2->x, v2 += 4
|
|
fipr fv8, fv0 ! FE, LERP(A1, B1)
|
|
fmov.s @IN1+, fr6 ! LS, A2 = v1->y, v1 += 4
|
|
fmov.s @IN2+, fr7 ! LS, B2 = v2->y, v2 += 4
|
|
|
|
fmov.s fr3,@OUT ! LS, OUT->x = LERP
|
|
add #4, OUT ! EX, OUT += 4
|
|
fipr fv8, fv4 ! FE, LERP(A2, B2)
|
|
add #4, IN1 ! EX, v1 += 4
|
|
add #4, IN2 ! EX, v2 += 4
|
|
|
|
fmov.s fr7,@OUT ! LS, OUT->y = LERP
|
|
add #4, OUT ! EX, OUT += 4
|
|
fmov.s fr1,@OUT ! LS, OUT->z = 0
|
|
add #4, OUT ! EX, OUT += 4
|
|
|
|
fmov.s @IN1+, fr2 ! LS, A1 = v1->u, v1 += 4
|
|
fmov.s @IN2+, fr3 ! LS, B1 = v2->u, v2 += 4
|
|
fipr fv8, fv0 ! FE, LERP(A1, B1)
|
|
fmov.s @IN1+, fr6 ! LS, A2 = v1->v, v1 += 4
|
|
fmov.s @IN2+, fr7 ! LS, B2 = v2->v, v2 += 4
|
|
|
|
fmov.s fr3,@OUT ! LS, OUT->u = LERP
|
|
add #4, OUT ! EX, OUT += 4
|
|
fipr fv8, fv4 ! FE, LERP(A2, B2)
|
|
add #4, IN1 ! EX, v1 += 4
|
|
add #4, IN2 ! EX, v2 += 4
|
|
fmov.s @IN1,fr2 ! LS, A1 = v1->w
|
|
fmov.s @IN2,fr3 ! LS, B1 = v2->w
|
|
fmov.s fr7,@OUT ! LS, OUT->v = LERP
|
|
add #8, OUT ! EX, OUT += 8
|
|
|
|
fipr fv8, fv0 ! FE, LERP(A1, B1)
|
|
add #-4, IN1 ! EX, v1 -= 4
|
|
add #-4, IN2 ! EX, v2 -= 4
|
|
fmov.s fr3,@OUT ! LS, OUT->w = lerp
|
|
add #-4, OUT ! EX, OUT -= 4
|
|
|
|
mov.l @IN1,CL1 ! LS, ACOLOR = v1->bgra
|
|
mov.l @IN2,CL2 ! LS, BCOLOR = v2->bgra
|
|
! Bypass interpolation if unnecessary
|
|
cmp/eq CL1,CL2 ! MT, T = ACOLOR == BCOLOR
|
|
bt.s 1f ! BR, if (T) goto 1;
|
|
mov CL1,CLO ! MT, OUTCOLOR = ACOLOR (branch delay instruction)
|
|
! Interpolate B
|
|
extu.b CL1,TM1 ! EX, val = ACOLOR.b
|
|
lds TM1,fpul ! CO, FPUL = val
|
|
float fpul,fr2 ! EX, fr2 = float(FPUL)
|
|
extu.b CL2,TM1 ! EX, val = BCOLOR.b
|
|
lds TM1,fpul ! CO, FPUL = val
|
|
float fpul,fr3 ! EX, fr3 = float(FPUL)
|
|
fipr fv8, fv0 ! FE, LERP(A1, B1)
|
|
shlr8 CL1 ! EX, ACOLOR >>= 8
|
|
ftrc fr3,fpul ! FE, FPUL = int(lerp)
|
|
shlr8 CL2 ! EX, BCOLOR >>= 8
|
|
sts fpul,TM2 ! CO, tmp = FPUL
|
|
! Interpolate G
|
|
extu.b CL1,TM1 ! EX, val = ACOLOR.g
|
|
lds TM1,fpul ! CO, FPUL = val
|
|
float fpul,fr2 ! EX, fr2 = float(FPUL)
|
|
extu.b CL2,TM1 ! EX, val = BCOLOR.g
|
|
lds TM1,fpul ! CO, FPUL = val
|
|
float fpul,fr3 ! EX, fr3 = float(FPUL)
|
|
fipr fv8, fv0 ! FE, LERP(A1, B1)
|
|
shlr8 CL1 ! EX, ACOLOR >>= 8
|
|
ftrc fr3,fpul ! FE, FPUL = int(lerp)
|
|
extu.b TM2,TM2 ! EX, tmp = (uint8)tmp
|
|
mov TM2,CLO ! MT, OUTCOLOR.b = tmp
|
|
shlr8 CL2 ! EX, BCOLOR >>= 8
|
|
sts fpul,TM2 ! CO, tmp = FPUL
|
|
! Interpolate R
|
|
extu.b CL1,TM1 ! EX, val = ACOLOR.r
|
|
lds TM1,fpul ! CO, FPUL = val
|
|
float fpul,fr2 ! EX, fr2 = float(FPUL)
|
|
extu.b CL2,TM1 ! EX, val = BCOLOR.r
|
|
lds TM1,fpul ! CO, FPUL = val
|
|
float fpul,fr3 ! EX, fr3 = float(FPUL)
|
|
fipr fv8, fv0 ! FE, LERP(A1, B1)
|
|
shlr8 CL1 ! EX, ACOLOR >>= 8
|
|
ftrc fr3,fpul ! FE, FPUL = int(lerp)
|
|
extu.b TM2,TM2 ! EX, tmp = (uint8)tmp
|
|
shll8 TM2 ! EX, tmp <<= 8
|
|
or TM2,CLO ! EX, OUTCOLOR.g |= tmp
|
|
shlr8 CL2 ! EX, BCOLOR >>= 8
|
|
sts fpul,TM2 ! CO, tmp = FPUL
|
|
! Interpolate A
|
|
extu.b CL1,TM1 ! EX, val = ACOLOR.a
|
|
lds TM1,fpul ! CO, FPUL = val
|
|
float fpul,fr2 ! EX, fr2 = float(FPUL)
|
|
extu.b CL2,TM1 ! EX, val = BCOLOR.a
|
|
lds TM1,fpul ! CO, FPUL = val
|
|
float fpul,fr3 ! EX, fr3 = float(FPUL)
|
|
fipr fv8, fv0 ! FE, LERP(A1, B1)
|
|
ftrc fr3,fpul ! FE, FPUL = int(lerp)
|
|
extu.b TM2,TM2 ! EX, tmp = (uint8)tmp
|
|
shll16 TM2 ! EX, tmp <<= 16
|
|
or TM2,CLO ! EX, OUTCOLOR.r |= tmp
|
|
sts fpul,TM2 ! CO, tmp = FPUL
|
|
extu.b TM2,TM2 ! EX, tmp = (uint8)tmp
|
|
shll16 TM2 ! EX, tmp <<= 16
|
|
shll8 TM2 ! EX, tmp <<= 8
|
|
or TM2,CLO ! EX, OUTCOLOR.a |= tmp
|
|
|
|
1:
|
|
mov.l CLO,@OUT ! LS, OUT->color = OUTCOLOR
|
|
mov.l @r15+,r5 ! LS, pop(r5)
|
|
rts ! CO, return after executing instruction in delay slot
|
|
mov.l @r15+,r4 ! LS, pop(r4)
|
|
|
|
.size _ClipLine, .-_ClipLine
|
|
.type _ClipLine,%function
|