@echo off

rem
rem  Triangle rasterization.bat  
rem  (c) 2008 Aleksej Borisov aka Imp5
rem


set tex0=.............................................................
set tex4=0000000000000000000000000000000000000000000000000000000000000

set /a width=61
set /a height=24

set /a width100=width*100
set /a height100=height*100


set /a trix1=40
set /a triy1=40
set /a trix2=40
set /a triy2=40
set /a trix3=40
set /a triy3=40
set /a tridx1=100
set /a tridy1=200
set /a tridx2=300
set /a tridy2=400
set /a tridx3=500
set /a tridy3=300


:main_loop

call :clear_buf
call :render_triangle_subpix %trix1% %triy1% %trix2% %triy2% %trix3% %triy3 tex4
call :flip_buf

set /a trix1+=tridx1
set /a triy1+=tridy1
if %trix1% LEQ -100 set /a tridx1=-tridx1
if %triy1% LEQ -100 set /a tridy1=-tridy1
if %trix1% GTR %width100% set /a tridx1=-tridx1
if %triy1% GTR %height100% set /a tridy1=-tridy1

set /a trix2+=tridx2
set /a triy2+=tridy2
if %trix2% LEQ -100 set /a tridx2=-tridx2
if %triy2% LEQ -100 set /a tridy2=-tridy2
if %trix2% GTR %width100% set /a tridx2=-tridx2
if %triy2% GTR %height100% set /a tridy2=-tridy2

set /a trix3+=tridx3
set /a triy3+=tridy3
if %trix3% LEQ -100 set /a tridx3=-tridx3
if %triy3% LEQ -100 set /a tridy3=-tridy3
if %trix3% GTR %width100% set /a tridx3=-tridx3
if %triy3% GTR %height100% set /a tridy3=-tridy3

goto main_loop



:clear_buf
	set scan0=%tex0%
	set scan1=%tex0%
	set scan2=%tex0%
	set scan3=%tex0%
	set scan4=%tex0%
	set scan5=%tex0%
	set scan6=%tex0%
	set scan7=%tex0%
	set scan8=%tex0%
	set scan9=%tex0%
	set scan10=%tex0%
	set scan11=%tex0%
	set scan12=%tex0%
	set scan13=%tex0%
	set scan14=%tex0%
	set scan15=%tex0%
	set scan16=%tex0%
	set scan17=%tex0%
	set scan18=%tex0%
	set scan19=%tex0%
	set scan20=%tex0%
	set scan21=%tex0%
	set scan22=%tex0%
	set scan23=%tex0%
	set scan24=%tex0%
goto EOF

:flip_buf
	cls
	echo %scan0%
	echo %scan1%
	echo %scan2%
	echo %scan3%
	echo %scan4%
	echo %scan5%
	echo %scan6%
	echo %scan7%
	echo %scan8%
	echo %scan9%
	echo %scan10%
	echo %scan11%
	echo %scan12%
	echo %scan13%
	echo %scan14%
	echo %scan15%
	echo %scan16%
	echo %scan17%
	echo %scan18%
	echo %scan19%
	echo %scan20%
	echo %scan21%
	echo %scan22%
	echo %scan23%
	echo %scan24%
goto EOF

:render_triangle_subpix
	set /a x1=%1
	set /a y1=%2
	set /a x2=%3
	set /a y2=%4
	set /a x3=%5
	set /a y3=%6

	if %y1% GTR %y2% (
		set /a tmp=y1
		set /a y1=y2
		set /a y2=tmp
		set /a tmp=x1
		set /a x1=x2
		set /a x2=tmp
	)

	if %y2% GTR %y3% (
		set /a tmp=y2
		set /a y2=y3
		set /a y3=tmp
		set /a tmp=x2
		set /a x2=x3
		set /a x3=tmp
	)

	if %y1% GTR %y2% (
		set /a tmp=y1
		set /a y1=y2
		set /a y2=tmp
		set /a tmp=x1
		set /a x1=x2
		set /a x2=tmp
	)

	set /a dx1=((x2-x1)*100)/(y2-y1+3)
	set /a dx2=((x3-x1)*100)/(y3-y1+3)
	set /a curx1=x1
	set /a curx2=x1
	set /a cury=y1
	
	:top_tri_loop
		set /a s_curx1=(curx1+50)/100
		set /a s_curx2=(curx2+50)/100
		set /a s_cury=(cury+50)/100
		call :horz_line %s_curx1% %s_curx2% %s_cury% %7
		set /a cury+=100
		set /a curx1+=dx1
		set /a curx2+=dx2
	if %cury% LEQ %y2% goto top_tri_loop


	set /a cury=y3
	set /a curx1=x3
	set /a curx2=x3
	set /a dx1=((x3-x2)*100)/(y3-y2+3)
	set /a dx2=((x3-x1)*100)/(y3-y1+3)
	:bottom_tri_loop
		set /a s_curx1=(curx1+50)/100
		set /a s_curx2=(curx2+50)/100
		set /a s_cury=(cury+50)/100
		call :horz_line %s_curx1% %s_curx2% %s_cury% %7
		set /a cury-=100
		set /a curx1-=dx1
		set /a curx2-=dx2
	if %cury% GEQ %y2% goto bottom_tri_loop

goto EOF

:horz_line
	if %3 LEQ -1 goto EOF
	if %3 GTR %height% goto EOF
	set /a xx1=%1
	set /a xx2=%2
	if %xx1% GTR %xx2% (
		set /a tmp=xx1
		set /a xx1=xx2
		set /a xx2=tmp
	)
	if %xx1% GTR %width% goto EOF
	if %xx2% LEQ -1 goto EOF
	if %xx1% LEQ -1 set /a xx1=0
	if %xx2% GTR %width% set /a xx2=width
	if %xx2% LSS %xx1% goto EOF
	set /a len=xx2-xx1
	set /a last=width-xx2
	call set fragment=%%%4:~0,%len%%%
	call set scan%3=%%scan%3:~0,%xx1%%%%fragment%%%scan%3:~%xx2%,%last%%%
goto EOF

:EOF