diff --git a/src/mandelbrotshader.cpp b/src/mandelbrotshader.cpp
index 9644659..ce91b75 100644
--- a/src/mandelbrotshader.cpp
+++ b/src/mandelbrotshader.cpp
@@ -53,12 +53,12 @@ void azrp_mandelbrot_close( void )
 struct command {
     uint8_t shader_id;
     uint8_t current_frag;
-    int32_t xmin;
-    int32_t xmax;
-    int32_t ymin;
-    int32_t ymax;
-    int32_t xinc;
-    int32_t yinc;
+    libnum::num xmin;
+    libnum::num xmax;
+    libnum::num ymin;
+    libnum::num ymax;
+    libnum::num xinc;
+    libnum::num yinc;
 };
 
 
@@ -70,12 +70,12 @@ void azrp_mandelbrot( void )
 
     cmd.shader_id = AZRP_SHADER_MANDELBROT;
     cmd.current_frag = 0;
-    cmd.xmin = (int32_t) (65536 * -3.0f);
-    cmd.xmax = (int32_t) (65536 * 2.0f);
-    cmd.ymin = (int32_t) (65536 * -2.0f);
-    cmd.ymax = (int32_t) (65536 * 2.0f);
-    cmd.xinc = (int32_t) (65536 * 5.0f/azrp_width);
-    cmd.yinc = (int32_t) (65536 * 4.0f/azrp_height);
+    cmd.xmin = libnum::num(-1.98f);
+    cmd.xmax = libnum::num(1.98f);
+    cmd.ymin = libnum::num(-1.12f);
+    cmd.ymax = libnum::num(1.12f);
+    cmd.xinc = libnum::num((2*1.98f)/azrp_width);
+    cmd.yinc = libnum::num((2*1.12f)/azrp_height);
     int fragmin = 0;
     int fragcount = (azrp_height >> 4) + 1;
 
@@ -92,12 +92,16 @@ void azrp_shader_mandelbrot( void *uniforms, void *comnd, void *fragment )
     struct command *cmd = (struct command *) comnd;
     uint16_t *frag = (uint16_t *) fragment;
 
-    int maxiter = 60;
+    int maxiter = 256;
 
-    int32_t zr, zi;
-
-    int32_t zrsave = cmd->xmin;
-    int32_t zisave = cmd->ymax - (int32_t) (65536 * (cmd->current_frag*16)*cmd->yinc);
+    libnum::num zr, zr2;
+    libnum::num zi, zi2;
+/*
+    libnum::num cr = libnum::num(-0.480f);
+    libnum::num ci = libnum::num(0.600f);
+*/
+    libnum::num zrsave = cmd->xmin;
+    libnum::num zisave = cmd->ymax - libnum::num(cmd->current_frag*16)*cmd->yinc;
 
     int u;
 
@@ -109,13 +113,62 @@ void azrp_shader_mandelbrot( void *uniforms, void *comnd, void *fragment )
         {
             zr = zrsave;
             zi = zisave;
+/*
+            zr2 = zr * zr;
+            zi2 = zi * zi;
 
-            u = mandelbrot( zr, zi, (2*2)<<16, maxiter );
+            u=0;
 
-            if (u==0) frag[offset + i] = C_RGB(255,255,255);
-            else frag[offset + i] = C_RGB(u*4,u*4,u*4);
+            while((zr2+zi2)<4 && (u<maxiter))
+            {
+                libnum::num temp = zr;
+                zr2 = zr * zr;
+                zi2 = zi * zi;
+                zr = zr2 - zi2 + cr;
+                zi = 2*zi*temp + ci;
+                u++;
+            }
+*/
+            u = mandelbrot( (int) zr, (int) zi, (2*2)<<16, maxiter );
+
+            if(u==maxiter)
+            {
+                frag[offset + i] = 0x0000;
+            }
+            else
+            {
+                int CR, CG, CB;
+
+                if (u<maxiter/4)
+                {
+                    CR = 0;
+                    CG = u*4;
+                    CB = 255;
+                }
+                else if (u<2*maxiter/4)
+                {
+                    CR = 0;
+                    CG = 255;
+                    CB = 255-(u-maxiter)/4;
+                }
+                else if (u<3*maxiter/4)
+                {
+                    CR = (u-2*maxiter)/4;
+                    CG = 255;
+                    CB = 0;
+                }
+                else if (u<4*maxiter/4)
+                {
+                    CR = 255;
+                    CG = 255-(u-3*maxiter)/4;
+                    CB = 0;
+                }
+
+                frag[offset + i] = C_RGB(CR,CG,CB);
+            }
 
             zrsave += cmd->xinc;
+
         }
 
         zrsave = cmd->xmin;