Do
// Clear the screen
Cls

// Set line1StartX, line1StartY, line1EndX, and line1EndY to variables
line1StartX=100
line1StartY=100
line1EndX = mousex()
line1EndY = mousey()

// Set line2StartX, line2StartY, line2EndX, and line2EndY to variables
line2StartX=20
line2StartY=200
line2EndX=1000
line2EndY=700

// Draw line1 in black
linec line1StartX, line1StartY, line1EndX, line1EndY,-1

// Draw line2 in green
linec line2StartX, line2StartY, line2EndX, line2EndY,$00ff00

// Check if lines intersect
State,x#,y#=Lines_Intersect(line1StartX, line1StartY, line1EndX, line1EndY,_
            line2StartX, line2StartY, line2EndX, line2EndY)

// Print intersect state
print State

// If lines intersect, draw a red circle at intersect point
if State
	Circlec X#,y#,10,true,$ff0000
endif

// Display the screen

sync
loop spacekey()

	end


 
Function Lines_Intersect(line1StartX, line1StartY, line1EndX, line1EndY, line2StartX, line2StartY, line2EndX, line2EndY)

// Initialize variables
intersects = False
intersectX = 0
intersectY = 0
s1_x# = line1EndX - line1StartX
s1_y# = line1EndY - line1StartY
s2_x# = line2EndX - line2StartX
s2_y# = line2EndY - line2StartY

// Calculate s and t
s# = (-s1_y# * (line1StartX - line2StartX) + s1_x# * (line1StartY - line2StartY)) / (-s2_x# * s1_y# + s1_x# * s2_y#)
t# = ( s2_x# * (line1StartY - line2StartY) - s2_y# * (line1StartX - line2StartX)) / (-s2_x# * s1_y# + s1_x# * s2_y#)

// Check if s and t are within valid range
if s# >= 0 and s# <= 1 and t# >= 0 and t# <= 1
	// Set intersects to true and calculate intersectX and intersectY
    intersects = True
    intersectX# = line1StartX + (t# * s1_x#)
    intersectY# = line1StartY + (t# * s1_y#)
EndIf

// Return intersects, intersectX, and intersectY

EndFunction intersects, intersectX#, intersectY#