compile using A86 assembler however you can adapt it for any other one easily... It just draws out a 3D like shape. It was annoying to get the angles right but suggestions on improvement to code is appreciated. :)
Adequately commented so it is understandable not fully as it is very repetitive..
NOTE: To use on vista DOSbox is required to enter graphical mode
~Jon~
; ***********************************
; * *
; * A program that will draw a 3D'ish *
; * shape *
; * *
; ***********************************
jmp start ;start command
;================================================
mode db 18 ;Resolution/Graphical mode
colour db 1 ;1 = Blue
a_x dw 100 ;Point a x coord
a_y dw 100 ;Point a y coord
b_x dw 100
b_y dw 300
c_x dw 180
c_y dw 380
d_x dw 250
d_y dw 25
e_x dw 332
e_y dw 300
;================================================
start:
mov ah,00
mov al,mode ;set graphic mode
int 10h ;enter graphic mode
mov ah,0Ch ;set write dot mode
mov al,colour ;set the colour
mov cx,a_x ;set point a
mov dx,a_y
draw_a_b: ;draw line ab
int 10h
inc dx
cmp dx,b_y
jnz draw_a_b
prep_b_c: ;setup line bc
mov cx,b_x
mov dx,b_y
draw_b_c: ;draw line bc
int 10h
inc cx
inc dx
cmp cx,c_x
jnz draw_b_c
cmp dx,c_y
jnz draw_b_c
prep_c_a: ;setup line ca
mov cx,c_x
mov dx,c_y
draw_c_a: ;draw line ca
int 10h
sub dx,7
sub cx,2
cmp dx,a_y
jnz draw_c_a
cmp cx,a_x
jnz draw_c_a
prep_a_d: ;setup line ad
mov cx,a_x
mov dx,a_y
draw_a_d: ;draw line ad
int 10h
add cx,2
sub dx,1
cmp cx,d_x
jnz draw_a_d
prep_c_e: ;setup line de
mov cx,c_x
mov dx,c_y
draw_c_e: ;draw line ce
int 10h
add cx,2
sub dx,1
cmp cx,e_x
jnz draw_c_e
prep_d_e: ;setup line dw
mov cx,d_x
mov dx,d_y
draw_d_e:
int 10h
add dx,7
add cx,2
cmp cx,e_x
jnz draw_d_e
GetKey:
mov ah,00
int 16h
end:
mov ah,00
mov al,03
int 10h
mov ah,04Ch
mov al,00
int 21h
Can you explain exactly what you want? Or what your problem is!
You are precarious, you draw a diagonal line but step +x,+y, check for x reaching the next waypoint axis exactly (zero flag check), but then check y. If y2-y1 is not equal to x2-x1 then you have a runaway. x is now past the axis and will continue until way off the screen and comes around again!
Instead of what you're doing, how about creating a function.
DrawLine( x1,y1, x2,y2 ). You can then create cool algorithms like a DDA
dx = |x2-x1| dy=|y2-y1|
if (dx < dy)
// step dy
else
// step dxStep on the longest axis and error correct on the sortest axis. Simple Binary math, and no wierd stepping logic.
If you track last x,y then you can also have a
DrawLineTo( x2, y2 )
Hmm, interesting stuff there, i'll look at it for improvement. It wasn't that there was a problem but it was more made available for reference to those who are learning as it could be helpful
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