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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

	.col equ ebp-4	;dd      ?

	.x1  equ ebp-6	;dw      ?

	.y1  equ  ebp-8  ;dw      ?;+8

	.x2  equ  ebp-10 ;dw      ?

	.y2  equ  ebp-12 ;dw      ?

	.x3  equ  ebp-14  ;dw      ?

	.y3  equ  ebp-16  ;dw      ?;+16

	.dx12 equ  ebp-20  ;  dd      ?

	.dx13 equ  ebp-24  ;  dd      ?;+24

	.dx23 equ  ebp-28  ;  dd      ?

	mov	ebp,esp

      ;  sub     esp,28

	push	edx

    .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

	push	eax

	push	ebx

	push	ecx

	sub	esp,12

	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	word[.x1],SIZE_X    ; {

	jg	.end_triangle

	cmp	word[.x2],SIZE_X     ; This can be optimized with effort

	jg	.end_triangle

	cmp	word[.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	dword[.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	dword[.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	dword[.dx23],0

	jmp	.yesZero3

    .noZero3:

	idiv	ebx

	mov	[.dx23],eax

    .yesZero3:

	movsx	eax,word[.x1]	; eax - xk1   ;;;

	shl	eax,ROUND

	mov	ebx,eax 	; ebx - xk2   ;;;

	movsx	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:

       mov     esp,ebp

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

	dec	ecx

	jecxz	.last_pix

    .ddraw:			; Drawing horizontally:

	;push    eax

	stosd			; 4 bytes at a time

	dec edi 		; point to the 4th

	loop	.ddraw

    .last_pix:

	stosw

	shr	eax,16

	stosb

;        mov     byte[edi],0     ; The last 4th will be reset

    .end_hor_l:

ret