diff --git a/organism/src/main.cpp b/organism/src/main.cpp
index 8bd7c2e..ee05d84 100644
--- a/organism/src/main.cpp
+++ b/organism/src/main.cpp
@@ -3,6 +3,7 @@
 #include <ESP32-HUB75-MatrixPanel-I2S-DMA.h>
 
 #include "main.h"
+#include "overlay.h"
 
 #define R1 42
 #define G1 40
@@ -57,6 +58,16 @@ void init_attractant() {
   //  int y = 15 + round(10 * cos(angle));
   //  attractant[x][y] = 15.0;
   //}
+
+  // draw a bitmap
+  //for(int x = 0; x < PANEL_WIDTH; x++) {
+  //  for(int y = 0; y < PANEL_HEIGHT; y++) {
+  //    int pixel_num = (y * PANEL_WIDTH) + x;
+  //    if(overlay[ pixel_num / 8 ] & (1 << (7 - (pixel_num % 8)) ) ){
+  //      attractant[x][y] = 15.0;
+  //    }
+  //  }
+  //}
 }
 
 void init_agents() {
@@ -150,16 +161,17 @@ void setupGaussianKernel(float* kernel, int width, float sigma) {
 
 #define GAUSS_WIDTH 5
 #define GAUSS_SIGMA 1.0
-#define DECAY_FACTOR 0.95
+#define DECAY_FACTOR 0.9
+float first_pass[PANEL_WIDTH][PANEL_HEIGHT];
 void gaussian_blur() {
   float kernel[GAUSS_WIDTH];
-  uint8_t first_pass[PANEL_WIDTH][PANEL_HEIGHT];
-  memset(first_pass, (uint8_t) 0, sizeof first_pass);
+   //  first_pass[PANEL_WIDTH][PANEL_HEIGHT];
+  memset(first_pass, 0.0, sizeof first_pass);
   setupGaussianKernel(kernel, GAUSS_WIDTH, GAUSS_SIGMA);
   // horizontal pass
   for (int x = 0; x < PANEL_WIDTH; x++) {
     for(int y = 0; y < PANEL_HEIGHT; y++) {
-      float sum = attractant[x][y] * kernel[0]; //0.0;
+      float sum = attractant[x][y] * DECAY_FACTOR * kernel[0]; //0.0;
       int additions = 1;
       for (int x_offset = 1; x_offset < GAUSS_WIDTH; x_offset++) {
         if (is_in_bounds(x+x_offset, y)) {
@@ -171,7 +183,7 @@ void gaussian_blur() {
           additions++;
         }
       }
-      first_pass[x][y] = (int) round(sum/GAUSS_WIDTH * DECAY_FACTOR);
+      first_pass[x][y] = sum/GAUSS_WIDTH;
     }
   }
   // vertical pass
@@ -189,13 +201,12 @@ void gaussian_blur() {
           additions++;
         }
       }
-      attractant[x][y] = (sum/GAUSS_WIDTH) * DECAY_FACTOR;
+      attractant[x][y] = sum/GAUSS_WIDTH;
     } 
   }
 }
 
 #define BLUR_KERNEL_SIZE 3
-float first_pass[PANEL_WIDTH][PANEL_HEIGHT];
 void box_blur() {
   //Serial.println("memset: starting");
   memset(first_pass, 0.0, sizeof first_pass);
@@ -204,7 +215,7 @@ void box_blur() {
   for (int x = 0; x < PANEL_WIDTH; x++) {
     for(int y = 0; y < PANEL_HEIGHT; y++) {
       float sum;
-      sum = attractant[x][y]; //0.0;
+      sum = attractant[x][y] * DECAY_FACTOR; //0.0;
       int additions = 1;
       for (int x_offset = 1; x_offset < BLUR_KERNEL_SIZE; x_offset++) {
         if (is_in_bounds(x+x_offset, y)) {
@@ -238,13 +249,13 @@ void box_blur() {
       float result = (sum/additions); // * DECAY_FACTOR;
       //Serial.printf("result: %f", result); //additions: %d\n", sum, additions);
       attractant[x][y] = (((8.0*attractant[x][y]) + result) / 9.0);
-      attractant[x][y] = attractant[x][y] * DECAY_FACTOR;
     } 
   }
 }
 
 void loop() {
   matrix ->flipDMABuffer();
+  delay(10);
   //matrix->clearScreen();
   matrix->fillScreenRGB888(15, 0, 10);
 
@@ -289,7 +300,6 @@ void loop() {
       agents[a].heading += AGENT_ANGLE * (PI * 2);
     }
   }
-  delay(10);
   iterations++;
   if (iterations > 64 && iterations % 64 == 0) { // (( == 0) {
     //gaussian_blur();
diff --git a/organism/src/overlay.h b/organism/src/overlay.h
new file mode 100644
index 0000000..f87ab77
--- /dev/null
+++ b/organism/src/overlay.h
@@ -0,0 +1,19 @@
+const unsigned char overlay [] PROGMEM = {
+	// 'bw2, 64x32px
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x1c, 0x00, 0x00, 
+	0x01, 0xf8, 0x00, 0x00, 0x00, 0x1c, 0x03, 0x80, 0x01, 0xfe, 0x00, 0x00, 0x00, 0x1c, 0x03, 0x80, 
+	0x01, 0xff, 0x00, 0x00, 0x00, 0x1c, 0x03, 0x80, 0x01, 0xc7, 0x80, 0x00, 0x00, 0x1c, 0x00, 0x00, 
+	0x01, 0xc3, 0x80, 0x00, 0x00, 0x1c, 0x00, 0x00, 0x01, 0xc3, 0x8f, 0xe1, 0xbe, 0x1c, 0x7b, 0x80, 
+	0x01, 0xc3, 0x8f, 0xe1, 0xff, 0x1c, 0x73, 0x80, 0x01, 0xc3, 0x88, 0x71, 0xe7, 0x1c, 0xe3, 0x80, 
+	0x01, 0xc3, 0x80, 0x71, 0xc3, 0x9d, 0xe3, 0x80, 0x01, 0xff, 0x00, 0x71, 0xc3, 0x9d, 0xc3, 0x80, 
+	0x01, 0xff, 0x03, 0xf1, 0xc3, 0x9f, 0x83, 0x80, 0x01, 0xfc, 0x0f, 0xf1, 0xc3, 0x9f, 0xc3, 0x80, 
+	0x01, 0xc0, 0x1f, 0x71, 0xc3, 0x9f, 0xc3, 0x80, 0x01, 0xc0, 0x3c, 0x71, 0xc3, 0x9d, 0xe3, 0x80, 
+	0x01, 0xc0, 0x38, 0x71, 0xc3, 0x9c, 0xe3, 0x80, 0x01, 0xc0, 0x38, 0x71, 0xc3, 0x9c, 0xf3, 0x80, 
+	0x01, 0xc0, 0x1c, 0xf1, 0xc3, 0x9c, 0x73, 0x80, 0x01, 0xc0, 0x1f, 0xf1, 0xc3, 0x9c, 0x7b, 0x80, 
+	0x01, 0xc0, 0x0f, 0xb1, 0x83, 0x9c, 0x3b, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
+};