kolibrios/programs/demos/3DS/FLAT3.ASM
ataualpa 0ceaac39cf Some programs now use window style Y=4
git-svn-id: svn://kolibrios.org@661 a494cfbc-eb01-0410-851d-a64ba20cac60
2007-10-20 18:12:58 +00:00

189 lines
3.5 KiB
NASM

draw_triangle:
;----------in - eax - x1 shl 16 + y1
;------------- -ebx - x2 shl 16 + y2
;---------------ecx - x3 shl 16 + y3
;---------------edx - color 0x00rrggbb
;---------------edi - pointer to screen buffer
@ch3:
cmp ax,bx
jg @ch1
@ch4: ; sort parameters
cmp bx,cx
jg @ch2
jle @chEnd
@ch1:
xchg eax,ebx
jmp @ch4
@ch2:
xchg ebx,ecx
jmp @ch3
@chEnd:
mov dword[@y1],eax ; ....and store to user friendly variables
mov dword[@y2],ebx
mov dword[@y3],ecx
mov [@col],edx
mov edx,eax ; eax,ebx,ecx are ORd together into edx which means that
or edx,ebx ; if any *one* of them is negative a sign flag is raised
or edx,ecx
test edx,80008000h ; Check both X&Y at once
jne @end_triangle
cmp [@x1],SIZE_X ; {
jg @end_triangle
cmp [@x2],SIZE_X ; This can be optimized with effort
jg @end_triangle
cmp [@x3],SIZE_X
jg @end_triangle ; }
shr eax,16
shr ebx,16
shr ecx,16
neg ax ; calculate delta 12
add ax,bx
cwde
shl eax,ROUND
cdq
mov bx,[@y2]
mov cx,[@y1]
sub bx,cx
;cmp ebx,0
jne @noZero1
mov [@dx12],0
jmp @yesZero1
@noZero1:
idiv ebx
mov [@dx12],eax
@yesZero1:
mov ax,[@x3] ; calculate delta 13
sub ax,[@x1]
cwde
shl eax,ROUND
cdq
mov bx,[@y3]
mov cx,[@y1]
sub bx,cx
;cmp ebx,0
jne @noZero2
mov [@dx13],0
jmp @yesZero2
@noZero2:
idiv ebx
mov [@dx13],eax
@yesZero2:
mov ax,[@x3] ; calculate delta 23 [dx23]
sub ax,[@x2]
cwde
shl eax,ROUND
cdq
mov bx,[@y3]
mov cx,[@y2]
sub bx,cx
;cmp ebx,0
jne @noZero3
mov [@dx23],0
jmp @yesZero3
@noZero3:
idiv ebx
mov [@dx23],eax
@yesZero3:
movzx eax,word[@x1] ; eax - xk1
shl eax,ROUND
mov ebx,eax ; ebx - xk2
movzx esi,word[@y1] ; esi - y
@next_line1:
mov ecx,eax ; ecx - x11
sar ecx,ROUND
mov edx,ebx ; edx - x12
sar edx,ROUND
cmp ecx,edx
jle @nochg
xchg ecx,edx
@nochg:
pusha
mov ebx,ecx
sub edx,ecx
mov ecx,edx
mov edx,esi
mov eax,[@col]
call @horizontal_line
popa
add eax,[@dx13]
add ebx,[@dx12]
inc esi
cmp si,[@y2]
jl @next_line1
movzx esi,word[@y2]
movzx ebx,word[@x2]
shl ebx,ROUND
@next_line2:
mov ecx,eax
sar ecx,ROUND
mov edx,ebx
sar edx,ROUND
cmp ecx,edx
jle @nochg1
xchg ecx,edx
@nochg1:
pusha
mov ebx,ecx
sub edx,ecx
mov ecx,edx
mov edx,esi
mov eax,[@col]
call @horizontal_line
popa
add eax,[@dx13]
add ebx,[@dx23]
inc esi
cmp si,[@y3]
jl @next_line2
@end_triangle:
ret
@horizontal_line:
;---------in
;---------eax - color of line, 0x00RRGGBB
;---------ebx - x1 - x position of line begin
;---------ecx - lenght of line
;---------edx - y position of line
;---------edi - pointer to buffer
jcxz @end_hor_l
; or edx,edx
; jl @end_hor_l
cmp edx,SIZE_Y
jg @end_hor_l
push eax
mov eax,SIZE_X*3
mul edx
add edi,eax ; calculate line begin adress
;add edi,ebx
;shl ebx,1
lea edi,[edi+ebx*2]
add edi,ebx
pop eax
cld
;mov dword[edi-3],0000FF00h
@ddraw: ; Drawing horizontally:
;push eax
stosd ; 4 bytes at a time
dec edi ; point to the 4th
;shr eax,16
;stosb
;pop eax
;pusha ; If you want to draw pixel-by-pixel
; mov eax,7 ; put image
; mov ebx,screen
; mov ecx,SIZE_X shl 16 + SIZE_Y
; mov edx,5 shl 16 + 20
; int 0x40
;popa
loop @ddraw
mov byte[edi],0 ; The last 4th will be reset
@end_hor_l:
ret