Shockwave wrote this in Freebasic I attempted to translate it into Yabasic. I did this for three reasons
1) To learn how to make a really cool fire effect
2) To learn how to make a really cool fire effect
3) To learn how to make a really cool fire effect
also to cut my teeth with Freebasic by comparing the same code in both Freebasic and Yabasic
man it runs at full speed in the FB but cripples yab even with the resolutions set really low
anyway I thought I would post it all credit goes to Shocky for this one
resx = 320
resy = 240
sz = 640/resx
open window 640, 512
dim buffer(resx*resy)
dim flame_buffer(resx*resy)
dim rd(resx), gr(resx), bl(resx)
dim cool_map(resx*resy)
cool_scroll = 0
generate_colours()
make_cool_map()
ticks = 0
oldtime = timer
repeat
gadd = gadd + 3
V = 50 + 39*cos(gadd/143)
scroll_aa()
m = 120
rem THIS BIT DRAWS THE FIRE ON THE SCREEN
for loopy = 0 to resx
flame_buffer(loopy + (resy/2*resx) ) = resx
next
a = 0
for y = 1 to resy
for x = 1 to resx a = a + 1
f = flame_buffer(a)
setrgb 1, rd(f), gr(f), bl(f)
fill box x*sz,y*sz to x*sz+sz,y*sz+sz
next
next
ticks = ticks + 1
? ticks," ", time$
setdispbuf draw
draw = 1 - draw
setdrawbuf draw
clear window
until (inkey$(0) <> "")
exit
sub scroll_aa()
d = resx*(resy-4) : rem SCREEN BOUNDS
rem MOVE OFFSET!
cool_scroll = cool_scroll + 3
rem RESET OFFSET IF OFF SCREEN
if (cool_scroll>resy) cool_scroll = cool_scroll - resy
rem CONVERT OFFSET INTO VALUE COMPATIBLE WITH OUR 1 DIMENSIONAL ARRAYS.
c = cool_scroll*resx
for a = resx to (resx*(resy-2))
c = c + 1 : rem MOVE ONE LINE DOWN.
rem IF C OFF SCREEN THEN PUT C BACK AT END OF IST SCAN LINE.
if (c>d) c = resx
rem 1280 IS XRES * 2 SO WE SCROLL THE FLAME BUFFER UP 2 LINES AND DARKEN AT SAME TIME TO SAVE SPEED.
flame_buffer(a) = flame_buffer(a+resx*2) - cool_map(c+resx*2)
rem STOP ILLEGAL COLOUR PALETTE REFERENCES.
if (flame_buffer(a)<0) flame_buffer(a) = 0
next
for a = resx to (resx*(resy-2))
rem CHEAP ANTI ALIAS OF FLAME BUFFER
b = (flame_buffer(a-resx) + flame_buffer(a+resx) + flame_buffer(a-1) + flame_buffer(a+1))
b = b/2
b = b/2
rem NB, THIS LOOP COULD PROBABLY BE COMBINED WITH ABOVE LOOP TO INCREASE SPEED MORE.
flame_buffer(a) = b
next
end sub
sub make_cool_map()
rem WE'LL PLOT 4000 POINTS IN THE MAP.
for a = 1 to 4000
rem RANDOM POINT IN COOL MAP = RANDOM VALUE UP TO resx
cool_map(ran((resx-1) * (resy-3))+resx) = ran(resx)
next
for c = 1 TO 10
rem THE NUMBER OF AA PASSES, MORE PASSES = BRIGHTER FLAMES.
for a = resx TO resx*(resy-2)
rem ACTUALLY DARKENS THE CENTRAL PIXEL SLIGHTLY, IS DESIRABLE..
b = (cool_map(a-resx)+cool_map(a+resx)+cool_map(a-1)+cool_map(a+1)+cool_map(a))*.2
if (b<000) b = 0
if (b>500) b = 500
cool_map(a) = int(b)
next
next
end sub
sub generate_colours()
rd = 0
gr = 0
bl = 0
for c = 1 to resx
if (rd<254) rd = rd + sz
if (c>resx/4) and (gr<255) gr = gr + sz
if (c>resx/2) and (bl<255) bl = bl + sz
rd(c) = rd
gr(c) = gr
bl(c) = bl
next
end sub
