1 files changed, 79 insertions, 62 deletions

diff --git a/software/pong3/pong3.c b/software/pong3/pong3.c
index 63ae56c..0e88ac8 100644
--- a/software/pong3/pong3.c
+++ b/software/pong3/pong3.c
@@ -13,59 +13,12 @@ gpu_write (unsigned int reg, unsigned int data)
   IOWR (GPU_0_BASE, reg << 2, data);
 }
 
-static int
-find_intersection (int x, int y, int xd, int yd, int t)
-{
-
-  // super lazy - we should use the power of MATHS
-
-  while (x != t)
-    {
-      x += xd;
-      y += yd;
-
-      if (y < 0)
-        y = 0;
-      if (y > 479)
-        y = 479;
-      if ((y == 479) || (y == 0))
-        yd = -yd;
-
-      if ((x == 639) || (x == 0))
-        xd = -xd;
-    }
-
-  return y;
-}
-
-static int
-dir (int a, int b)
-{
-  if (a > b)
-    return 1;
-  if (a < b)
-    return -1;
-  return 0;
-}
-
-static void
-move_bat (int *b, int db)
-{
-
-  *b += dir (db, *b);
-  if (*b < 20)
-    *b = 20;
-  if (*b > 459)
-    *b = 459;
-
-}
-
 static void
 load_sprite (void)
 {
   //                      RRR GGG BBB
   // set the sprite color 111 010 000 - orange
-  gpu_write (4, 0x01D0);
+  gpu_write (5, 0x01D0);
 
   // squirt the bromium logo into the sprite
   gpu_write (0x10, 0x00C0);
@@ -86,6 +39,60 @@ load_sprite (void)
   gpu_write (0x1f, 0x00C0);
 }
 
+
+static int
+dir (int a, int b)
+{
+  if (a > b)
+    return 1;
+  if (a < b)
+    return -1;
+  return 0;
+}
+
+static void
+move_bat (int *b, int db)
+{
+  *b += dir (db, *b);
+}
+
+static int
+squish (int *v, int min, int max)
+{
+  if (*v < min)
+    {
+      *v = min;
+      return 1;
+    }
+  if (*v >= max)
+    {
+      *v = max - 1;
+      return 1;
+    }
+  return 0;
+}
+
+static int
+find_intersection (int x, int y, int xd, int yd, int t)
+{
+
+  // super lazy - we should use the power of MATHS
+
+  while (x != t)
+    {
+      x += xd;
+      y += yd;
+
+      if (squish (&y, 0, 480))
+        yd = -yd;
+
+      if (squish (&x, 0, 640))
+        xd = -xd;
+    }
+
+  return y;
+}
+
 int
 main (void)
 {
@@ -117,35 +124,45 @@ main (void)
         {
           x += xd;
           y += yd;
-          if (y < 0)
-            y = 0;
-          if (y > 479)
-            y = 479;
-          if ((y == 479) || (y == 0))
+
+
+          if (squish (&y, 0, 480))
             yd = -yd;
 
-          if ((x == 639) || (x == 0))
+          if (squish (&x, 0, 640))
             {
-              xd = -xd;
+              xd = (rand () % 3) + 1;
+              if (x)
+                xd = -xd;
               yd = rand () % 7;
               yd -= 3;
-              dbat0 = find_intersection (x + xd, y + yd, xd, yd, 0);
-              dbat1 = find_intersection (x + xd, y + yd, xd, yd, 639);
+
+              if (x)
+                {
+                  dbat0 = find_intersection (x + xd, y + yd, xd, yd, 0);
+                  dbat1 = 480 / 2;
+                }
+              else
+                {
+                  dbat0 = 480 / 2;
+
+                  dbat1 = find_intersection (x + xd, y + yd, xd, yd, 639);
+                }
             }
 
           move_bat (&bat0, dbat0);
           move_bat (&bat1, dbat1);
 
 
-          gpu_write (0, x);
-          gpu_write (1, y);
+          gpu_write (1, x + 0x80);
+          gpu_write (2, y + 0x80);
+          gpu_write (3, bat0 + 0x80);
+          gpu_write (4, bat1 + 0x80);
 
-          gpu_write (2, bat0);
-          gpu_write (3, bat1);
+          gpu_write (0, 0);
 
           msleep (2);
         }
     }
 }
 
-//-------------------------------------------------------------------------