Now a further version which contains aliens that can be shot.
About user interface: press on the bottom area on the left or right side to position your ship; touch above the ship to shot. Try to kill all aliens!
still some things are missing...
Code: Select all
graphics
option base 1
randomize
pi=3.1415926
adjust_loop:
points=0
stars=40
shots=10
aliens=10
explosions=5
explosionpoints=20
sx=screen_width()
sy=screen_height()
cx=sx/2
u=(sx+sy)/40
dim stars_x(stars)
dim stars_y(stars)
dim step(stars)
dim shot_x(shots)
dim shot_y(shots)
dim shot_step(shots)
dim alien_x(aliens)
dim alien_y(aliens)
dim alien_step(aliens)
dim alien_angle(aliens)
dim alien_cnt(aliens)
dim explosion_x(explosions)
dim explosion_y(explosions)
dim explosion_size(explosions)
dim explosion_px(explosionpoints)
dim explosion_py(explosionpoints)
for i=1 to explosionpoints
explosion_px(i)=rnd(1)-rnd(1)
explosion_py(i)=rnd(1)-rnd(1)
next i
gosub init_stars
for lp=1 to 5
gosub add_alien
next lp
loop:
graphics lock
graphics clear 0,0,0
if cx<u then cx=u
if cx>sx-u then cx=sx-u
gosub stars
gosub ship
gosub alien
' check left, right and shot touch
for t=0 to 1
ty=touch_y(t)
if ty>=sy-5*u and ty<=sy then
tx=touch_x(t)
if tx<5*u then
cx=cx-u/2
else
if tx>sx-5*u then cx=cx+u/2
end if
else
if ty>0 then
shotstep=-u/3
shotx=cx
shoty=sy-u*2
gosub add_shot
end if
end if
next t
gosub shot
gosub display
gosub explosion
graphics unlock
if sx=screen_width() then goto loop
goto adjust_loop
ship:
draw color 1,1,1
draw size 5
draw line cx-u,sy to cx+u,sy
draw line to cx,sy-2*u
draw line to cx-u,sy
return
stars:
draw size 2
for i=1 to stars
draw color rnd(1),rnd(1),rnd(1)
y=stars_y(i)
draw pixel stars_x(i),y
y=y+step(i)
if y>sy then y=0
stars_y(i)=y
next i
return
init_stars:
for i=1 to stars
step(i)=rnd(1)*2
stars_x(i)=rnd(sx)
stars_y(i)=rnd(sy)
next i
return
alien:
for i=1 to aliens
c=alien_cnt(i)
if c>0 then
x=alien_x(i)
y=alien_y(i)
draw color 1,rnd(0.5)+0.5,rnd(0.5)+0.5
draw size 5
draw line x-2*u,y to x,y-2*u
draw line to x+2*u,y
draw line to x,y+2*u
draw line to x-2*u,y
s=alien_step(i)
h=(alien_angle(i)-90)/180*pi
x=x+s*cos(h)
y=y+s*sin(h)
if x<0 then
x=sx
else
if x>sx then x=0
end if
alien_x(i)=x
alien_y(i)=y
c=c-1
if c=0 then
c=rnd(15*u)+1
alien_angle(i)=rnd(360)
alien_step(i)=rnd(1)*3
shotx=x
shoty=y
shotstep=u/3
gosub add_shot
else
if y<0 or y>sy/2 then
a=alien_angle(i)-180
if a<0 then a=a+360
alien_angle(i)=a
end if
end if
alien_cnt(i)=c
end if
next i
return
add_alien:
found=0
for i=1 to aliens
if alien_cnt(i)=0 and found=0 then found=i
next i
if found>0 then
alien_x(found)=rnd(sx)
alien_y(found)=0
alien_angle(found)=rnd(90)+135
alien_step(found)=rnd(1)*3
alien_cnt(found)=rnd(u*15)+1
end if
return
add_explosion:
found=0
for ei=1 to explosions
if explosion_size(ei)=0 then found=ei
next ei
if found>0 then
explosion_x(found)=explosionx
explosion_y(found)=explosiony
explosion_size(found)=1
end if
return
explosion:
for ei=1 to explosions
s=explosion_size(ei)
if s>0 then
x=explosion_x(ei)
y=explosion_y(ei)
draw size 5
for ex=1 to explosionpoints
if rnd(1)<0.5 then
draw color 1,0,0
else
draw color 1,1,0
end if
draw pixel x+explosion_px(ex)*s,y+explosion_py(ex)*s
next ex
s=s+2
if s>=u*4 then s=0
end if
explosion_size(ei)=s
next ei
return
shot:
for i=1 to shots
x=shot_x(i)
y=shot_y(i)
if y>0 and y<sy then
draw color rnd(1),rnd(1),rnd(1)
draw line x,y+u to x,y
stp=shot_step(i)
y=y+stp
if stp<0 then
f=0
for ai=1 to aliens
if alien_cnt(ai)>0 and f=0 then
ax=alien_x(ai)
ay=alien_y(ai)
if x>=ax-2*u and x<=ax+2*u and y>=ay-2*u and y<=ay+2*u then
explosionx=x
explosiony=y
gosub add_explosion
y=0
alien_cnt(ai)=0
f=ai
points=points+1000
end if
end if
next ai
else
end if
shot_y(i)=y
end if
next i
return
add_shot:
' do not allow new shots if one lower shot is still visible
found=0
for si=1 to shots
y=shot_y(si)
if y<=0 or y>sy then found=si
if shot_step(si)<0 and y>sy-5*u then return
next si
if found>0 then
shot_x(found)=shotx
shot_y(found)=shoty
shot_step(found)=shotstep
end if
return
display:
fill color 1,1,0.5
draw color 1,0,0
fill rect 0,0 to sx,20
draw text "SCORE: "& points at 10,0
return
