buggy flood fill

include/tools.bm

@@ -1,6 +1,6 @@
 
 
-sub filledPolygon (Points() as single, col as long)
+sub filledPolygon (Points() as long, col as long)
     dim i as integer, j as integer
     dim x1 as single, y1 as single, x2 as single, y2 as single
     dim intersectX as single
@@ -67,8 +67,9 @@ Sub polygon (pa() As Long,col as long)
     For i = 2 To UBound(pa) Step 2
         thickLine pa(i - 2), pa(i - 1),pa(i), pa(i + 1),col
     Next i
-    thickLine pa(i - 1), pa(i - 2),pa(0), pa(1),col
+    thickLine pa(ubound(pa)-1), pa(ubound(pa)),pa(0), pa(1),col
 End Sub
+
 sub thickcircle(x, y, r, col as long)
     if state.brushsize <= 1 then
         circle (x, y), r, col
@@ -143,3 +144,100 @@ sub filledcircle(x,y,r,col as long)
             line (x-tx,y+ty)-(x+tx,y+ty),col
         wend
 end sub
+
+
+sub floodfill (x as integer, y as integer, fillcolor as long)
+    dim as integer leftx, rightx, currenty
+    dim as integer arrsize, stackptr
+    
+    ' Create a stack for storing coordinates
+    arrsize = 1000 ' Adjust based on expected complexity
+    redim stack(1 to arrsize, 1 to 2) as integer
+    stackptr = 0
+    
+    ' Get the color at starting point
+    dim startcolor as long
+    startcolor = point(x, y)
+    
+    ' If starting on boundary color or fill color, exit
+    if startcolor = fillcolor then exit sub
+    
+    ' Push starting point to stack
+    stackptr = stackptr + 1
+    stack(stackptr, 1) = x
+    stack(stackptr, 2) = y
+    
+    ' Process until stack is empty
+    do while stackptr > 0
+        ' Pop a point from stack
+        x = stack(stackptr, 1)
+        y = stack(stackptr, 2)
+        stackptr = stackptr - 1
+        
+        ' Skip if current point is not startcolor
+        if point(x, y) <> startcolor then _continue
+        
+        ' Find leftmost point on this scanline
+        leftx = x
+        do while leftx > 0 and point(leftx - 1, y) = startcolor
+            leftx = leftx - 1
+        loop
+        
+        ' Find rightmost point on this scanline
+        rightx = x
+        do while rightx < _width - 1 and point(rightx + 1, y) = startcolor
+            rightx = rightx + 1
+        loop
+        
+        ' Fill the scanline
+        line (leftx, y)-(rightx, y), fillcolor
+        
+        ' Check scanline above
+        currenty = y - 1
+        if currenty >= 0 then
+            for x = leftx to rightx
+                if point(x, currenty) = startcolor then
+                    ' Push seed point to stack
+                    stackptr = stackptr + 1
+                    if stackptr > arrsize then
+                        ' Resize stack if needed
+                        arrsize = arrsize * 2
+                        redim _preserve stack(1 to arrsize, 1 to 2) as integer
+                    end if
+                    stack(stackptr, 1) = x
+                    stack(stackptr, 2) = currenty
+                    
+                    ' Skip adjacent pixels of same color
+                    do while x <= rightx and point(x, currenty) = startcolor
+                        x = x + 1
+                    loop
+                    x = x - 1 ' Adjust for loop increment
+                end if
+            next x
+        end if
+        
+        ' Check scanline below
+        currenty = y + 1
+        if currenty < _height then
+            for x = leftx to rightx
+                if point(x, currenty) = startcolor then
+                    ' Push seed point to stack
+                    stackptr = stackptr + 1
+                    if stackptr > arrsize then
+                        ' Resize stack if needed
+                        arrsize = arrsize * 2
+                        redim _preserve stack(1 to arrsize, 1 to 2) as integer
+                    end if
+                    stack(stackptr, 1) = x
+                    stack(stackptr, 2) = currenty
+                    
+                    ' Skip adjacent pixels of same color
+                    do while x <= rightx and point(x, currenty) = startcolor
+                        x = x + 1
+                    loop
+                    x = x - 1 ' Adjust for loop increment
+                end if
+            next x
+        end if
+    loop
+end sub