X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?a=blobdiff_plain;f=examples%2Fmandelbrot.4th;fp=examples%2Fmandelbrot.4th;h=d31b028cacac3b5b1000b30cf3ccae6382b64de5;hb=3497073ce4fa8c523c05c4959b0c574c3c3bebcc;hp=5707acb5ff15b719efe5f422ba4d8a7c51e23d26;hpb=8da6476a6cfd583220ad70d1f8360ae404ea1c6f;p=forth.jl.git

diff --git a/examples/mandelbrot.4th b/examples/mandelbrot.4th
index 5707acb..d31b028 100644
--- a/examples/mandelbrot.4th
+++ b/examples/mandelbrot.4th
@@ -32,19 +32,22 @@
 
 : csq 2dup c* ;
 
+
+: conj ( x y -- x -y )
+    negate
+;
+
 : cmagsq ( x1 y1 -- mag )
-    csq abs
+    2dup conj c* +
 ;
 
 ( --- Mandelbrot set calculations  --- )
 
 : iterate ( cr ci zr zi -- cr ci z'r z'i )
-    csq c+
+    2over 2swap csq c+
 ;
 
 : inSet? ( cr ci -- res )
-    DEBUGON
-
     0 0     ( z_0 = 0 )
     
     true    ( flag indicating set membership )
@@ -53,7 +56,7 @@
 
         iterate
         2dup cmagsq
-        4 >scaled > if
+        4 0 >scaled > if
             false ( not in set )
             leave
         then
@@ -66,19 +69,30 @@
 ;
 
 : xsteps 100 ;
-: ysteps 50 ;
+: ysteps 30 ;
 
 ( Draw the Mandelbrot Set!)
 : mandel ( x1 y1 x2 y2 -- )
 
-    1 pick 4 pick -
-    2 pick 5 pick do
-        i 0 inSet? if
-            42 emit
-        else
-            '.' emit
-        then
+    0 pick 3 pick - ysteps /
+    1 pick 4 pick do
+
+        2 pick 5 pick - xsteps /
+        3 pick 6 pick do
+
+            i j inSet? if
+                42 emit
+            else
+                space
+            then
+
+        dup +loop
+        drop
+
+        cr
+
     dup +loop
+    drop
 ;
 
 ( Clean up - hide non-standard multiplication def. )