;PUTPIXEL -> RGBPIXEL
locals
n dd ?
d_x dd ?
d_y dd ?
sx dd ? ;ширина буфера в пикселях
pp_inc_1 dd ?
pp_inc_2 dd ?
a dd ? ;register int
if TGL_FEATURE_RENDER_BITS eq 24
r dd ? ;register unsigned int
g dd ?
b dd ?
end if
if INTERP_Z eq 1
pz dd ? ;register unsigned short *
zinc dd ?
z dd ? ;register int
zz dd ?
end if
endl
pushad
mov eax,[p1]
mov ebx,[p2]
mov ecx,[ebx+offs_zbup_y]
cmp [eax+offs_zbup_y], ecx ;if (p1.y > p2.y)
jg @f
jl .end_0 ;if (p1.y != p2.y)
mov ecx,[ebx+offs_zbup_x]
cmp [eax+offs_zbup_x], ecx ;if (p1.x > p2.x)
jle .end_0 ;if (p1.x <= p2.x)
@@: ;if (p1.y > p2.y || (p1.y == p2.y && p1.x > p2.x))
mov [p1],ebx
mov [p2],eax
.end_0:
mov eax,[zb]
mov edx,[eax+offs_zbuf_xsize]
mov [sx],edx
mov ecx,[p1]
mov edi,[eax+offs_zbuf_linesize]
imul edi,[ecx+offs_zbup_y]
mov edx,[ecx+offs_zbup_x]
imul edx,PSZB
add edi,edx
add edi,[eax+offs_zbuf_pbuf] ;edi = (zb.pbuf + zb.linesize*p1.y + p1.x*PSZB)
if INTERP_Z eq 1
mov edx,[ecx+offs_zbup_y]
imul edx,[sx]
add edx,[ecx+offs_zbup_x]
add edx,[eax+offs_zbuf_zbuf]
mov [pz],edx ;pz = zb.zbuf + (p1.y*sx + p1.x)
mov edx,[ecx+offs_zbup_z]
mov [z],edx ;z = p1.z
end if
mov ebx,[p2]
mov eax,[ebx+offs_zbup_x]
sub eax,[ecx+offs_zbup_x]
mov [d_x],eax ;d_x = p2.x - p1.x
mov eax,[ebx+offs_zbup_y]
sub eax,[ecx+offs_zbup_y]
mov [d_y],eax ;d_y = p2.y - p1.y
if TGL_FEATURE_RENDER_BITS eq 24
; for 24 bits, we store the colors in different variables
mov eax,[ebx+offs_zbup_r]
shr eax,8
mov [r],eax ;r = p2.r >> 8
mov eax,[ebx+offs_zbup_g]
shr eax,8
mov [g],eax ;g = p2.g >> 8
mov eax,[ebx+offs_zbup_b]
shr eax,8
mov [b],eax ;b = p2.b >> 8
end if
macro RGBPIXEL
{
if TGL_FEATURE_RENDER_BITS eq 24
mov eax,[r]
mov byte[edi],al
mov eax,[g]
mov byte[edi+1],al
mov eax,[b]
mov byte[edi+2],al
;;; else
;;; mov eax,[color]
;;; mov [edi],eax
end if
}
macro PUTPIXEL
{
if INTERP_Z eq 1
local .end_0
mov eax,[z]
shr eax, ZB_POINT_Z_FRAC_BITS
mov [zz],eax
cmp eax,[pz]
jl .end_0
RGBPIXEL
mov eax,dword[zz]
mov [pz],eax
.end_0:
else ; INTERP_Z
RGBPIXEL
end if ; INTERP_Z
}
macro DRAWLINE d_x,d_y,inc_1,inc_2
{
mov eax,d_x
mov [n],eax
if INTERP_Z eq 1
mov ebx,[p1]
mov eax,[p2]
mov eax,[eax+offs_zbup_z]
sub eax,[ebx+offs_zbup_z]
xor edx,edx
div dword[n]
mov [zinc],eax ;zinc=(p2.z-p1.z)/n
end if
shl dword d_y,1
mov eax, d_y
sub eax, d_x
mov [a],eax ;a=2*d_y-d_x
shl dword d_x,1
mov eax, d_y
sub d_x,eax
mov eax,inc_1
imul eax,PSZB
mov [pp_inc_1],eax ;pp_inc_1 = inc_1*PSZB
mov eax,inc_2
imul eax,PSZB
mov [pp_inc_2],eax ;pp_inc_2 = inc_2*PSZB
local .do_cycle
local .els_0
local .end_0
align 4
.do_cycle:
PUTPIXEL
if INTERP_Z eq 1
mov eax,[zinc]
add [z],eax
end if
cmp dword[a],0
jle .els_0
add edi,[pp_inc_1]
if INTERP_Z eq 1
mov eax,inc_1
add [pz],eax
end if
mov eax,d_x
sub [a],eax
jmp .end_0
.els_0:
add edi,[pp_inc_2]
if INTERP_Z eq 1
mov eax,inc_2
add [pz],eax
end if
mov eax,d_y
add [a],eax
.end_0:
dec dword[n]
cmp dword[n],0
jge .do_cycle
}
; fin macro
mov eax,[d_x]
cmp eax,0
jne .els_0
cmp dword[d_y],0
jne .els_0
;if (d_x==0 && d_y==0)
PUTPIXEL
jmp .end_2
.els_0:
cmp eax,0
jle .els_3
;if (d_x > 0)
mov esi,[sx]
inc esi
cmp eax,[d_y]
jl .els_2
;if (d_x >= d_y)
DRAWLINE [d_x], [d_y], esi, 1
jmp .end_2
.els_2:
DRAWLINE [d_y], [d_x], esi, [sx]
jmp .end_2
.els_3:
xor eax,eax
sub eax,[d_x]
mov [d_x],eax
mov esi,[sx]
dec esi
cmp eax,[d_y]
jl .els_4
;if (d_x >= d_y)
DRAWLINE [d_x], [d_y], esi, -1
jmp .end_2
.els_4:
DRAWLINE [d_y], [d_x], esi, [sx]
.end_2:
popad
ret
endp
restore INTERP_Z
; internal defines
purge DRAWLINE
purge PUTPIXEL
purge RGBPIXEL