Hi noobnerd,

It looks incredible, and great work.

What you have done is what i am looking for a long time and trying myself.

But could you help me to complete my demo.

I have found the missing functions

[edit]

**I got it to work.**

But having problems with the alpha/blendmode.

Here is the demo code (no media needed):
set display mode 800,600,32,1
set image colorkey 0,0,0
make image 3,screen width(),screen height()
make image 5,screen width(),screen height()
make image 4,1024,1024
draw to image 4
for r=1 to 512
a2fillcircle 512,512,512-r,rgb(r/2,r/2,r/2)
next r
dim v(6)
for i=0 to 6
v(i)=i
make vector2 v(i)
next i
//v(0) wall pos
//v(1) light to wall dist
//v(2) light to corner dist
//v(3) "
//v(4) light to left corner dist && shadow left corner
//v(5) light to right corner dist && shadow right corner
//v(6) light pos
make image 1,10,10
draw to image 1
a2fillbox 1,1,9,9,RGB(53,27,0)
a2box 0,0,10,10,RGB(0,0,0)
type testdata
w
endtype
global a
global b
a=100
b=100
dim n(a,b) as testdata
for i=1 to a
for j= 1 to b
n(i,j).w=(rnd(100)=1)
next j
next i
dim corner(4)
for i=1 to 4
corner(i)=6+i
make vector2 corner(i)
next i
set vector2 corner(1),5,5
set vector2 corner(2),5,-5
set vector2 corner(3),-5,5
set vector2 corner(4),-5,-5
global density#
density#=8
draw to bitmap 0
hide mouse
do
lightmap(50,59,20,20,100)
lightmap(mousex(),mousey(),100,20,20)
a2drawimage 3,0,0,0,0,0,1,0,rgb(255,255,255) // draw the lightmap
for i = 0 to a
for j = 0 to b
if n(i,j).w then a2drawimage 1,(i-0.5)*density#,(j-0.5)*density#,0,0,0,1,0,RGB(255,255,255) // draw the boxes
next j
next i
loop
function lightmap(x#,y#,cr,cg,cb) ` x#/y# = position of your light , ip/jp = grid position of your light , cr,cg,cb = colors of the light
range# = (cr+cg+cb)*2
set vector2 v(6),x#,y# ` range is calclated from the light strength , v(6) is used to store the light position
draw to image 3 ` draw to some rendertarget with screen dimensions ( make image 3,screen width(),screen height() )
a2setblendmode 2,1,1
a2fillbox 0,0,w,h,rgb(0,0,0) ` set blendmode to normal , this line does the same as "cls" clears the rendertarget
a2drawimage 4,x#,y#,0,512,512,range#/512.0,0,rgb(cr,cg,cb) `paste the light image
for i = 0 to a
for j = 0 to b ` go through all the grid squares ( might be faster if you had a list with just the wall blocks )
if n(i,j).w = 1 and squaredist(i*density#,j*density#,x#,y#) < range#*range# ` if theres a wall and its within range of the light
set vector2 v(0),i*density#,j*density# ` store the walls position in a vector
subtract vector2 v(1),v(0),v(6) ` get the vetor from light to wall
mina1# = 10000000 : mina2# = 10000000 ` set initial values
for n = 1 to 4 ` corner vectors
add vector2 v(2),v(1),corner(n)
l# = length vector2(v(2)) ` goes through all the corners of the wall to determine which 2 are at the "edge" of the square
a# = dot product vector2(v(1),v(2))/l#
if a# < mina1#
mina2# = mina1#
min2 = min1
l2# = l1#
mina1# = a#
min1 = n
l1# = l# `stores the 2 corners in min1 and min2
else
if a# < mina2#
mina2# = a#
min2 = n
l2# = l#
endif
endif
next n
if min1 > 0 and min2 > 0
add vector2 v(2),v(0),corner(min1)
add vector2 v(3),v(0),corner(min2)
endif
add vector2 v(4),v(1),corner(min1)
add vector2 v(5),v(1),corner(min2)
lenvec(v(4),v(4),range#-l1#+150)
lenvec(v(5),v(5),range#-l2#+150)
add vector2 v(4),v(2),v(4)
add vector2 v(5),v(3),v(5) `cast vectors from the corners outward from the light far enough
a2filltriangle x vector2(v(2)),y vector2(v(2)),x vector2(v(3)),y vector2(v(3)),x vector2(v(4)),y vector2(v(4)),rgb(0,0,0) `draw triangles to fill the quad that is the shadow
a2filltriangle x vector2(v(5)),y vector2(v(5)),x vector2(v(3)),y vector2(v(3)),x vector2(v(4)),y vector2(v(4)),rgb(0,0,0)
a2fillbox (i+0.5)*density#,(j+0.5)*density#,(i-0.5)*density#,(j-0.5)*density#,rgb(0,0,0) ` fill the square with a shadow
endif
next j
next i
draw to image 5 `draw to the mainlightmap
a2setblendmode 2,2,1 ` additive blending
a2drawimage 3,0,0,0,0,0,1,0,rgb(255,255,255) ` paste the generated lightmap onto the main lightmap
a2setblendmode 2,1,1
a2dot 0,0,512 `reset the blendmode to normal
draw to bitmap 0 `draw to the main bitmap
endfunction
function squaredist(x1#,y1#,x2#,y2#)
d# = (x1#-x2#)^2+(y1#-y2#)^2
endfunction d#
function lenvec(v,v1,len#)
normalize vector2 v,v1
multiply vector2 v,len#
endfunction

[/edit]

sorry for my English and thank you for sharing with us.