Diff: main.cpp

Revision:

1:6fab471dffd5

Parent:

0:f2f2c76b9816

--- a/main.cpp	Sun Dec 07 10:17:42 2014 +0000
+++ b/main.cpp	Mon Dec 08 11:37:21 2014 +0000
@@ -1,3 +1,5 @@
+/** maze_vt100 a simple maze using vt100 and MMA8451Q libraries
+ */
 #include "mbed.h"
 #include "MMA8451Q.h"
 #include "vt100.h"
@@ -9,8 +11,6 @@
 #define DIR_RIGHT 3 
 #define DIR_LEFT  4
 
-
-
 #define MMA8451_I2C_ADDRESS (0x1D<<1)
 
 typedef struct _pos {
@@ -20,7 +20,23 @@
 
 MMA8451Q acc(PTE25, PTE24, MMA8451_I2C_ADDRESS) ;
 vt100 tty ;
+float threshold = 0.2 ;
 
+/** Check if two pos_type values are same
+ * @param pos_type a
+ * @param pos_type b
+ * @returns if a and b are same position
+ */
+bool isSame(pos_type a, pos_type b)
+{
+    return((a.x == b.x)&&(a.y == b.y)) ;
+}
+
+/** Draw the maze defined in the "maze.h"
+ * @param pos_type *current actually the start point
+ * @param pos_type *goal the position of the goal
+ * @note those params are actually returned by this function
+ */
 void drawTextMaze(pos_type *current, pos_type *goal) 
 {
     int x, y ;
@@ -33,27 +49,30 @@
     for (y = 0 ; y < MAZE_H ; y++ ) {
         for (x = 0 ; x < MAZE_W ; x++ ) {
             switch(maze[y][x]) {
-            case 0:  
+            case 0:  // path
                 c = ' ' ; 
-                break ; // path
-            case 1:  
+                break ; 
+            case 1:  // wall
                 c = ' ' ; 
                 tty.setBG(0) ; // set background to black
                 tty.setFG(7) ; // set foreground to white
-                break ; // wall
-            case 2:  c = 'S' ;
+                break ; 
+            case 2: // Start point  
+                c = 'S' ;
                 current->x = x ;
                 current->y = y ; 
                 break ; // start
-            case 3:  c = 'G' ;
+            case 3: // Goal  
+                c = 'G' ;
                 tty.green() ;
                 goal->x = x ;
                 goal->y = y ; 
-                break ; // goal
-            default: c = '?' ; break ; // wth?
+                break ; 
+            default: // should not be here 
+                c = '?' ; 
+                break ; // wth?
             }
-            tty.locate(x+1, y+1) ;
-            printf("%c", c) ;
+            tty.putChar(x+1, y+1, c) ;
             tty.setBG(7) ; // set background to white
             tty.setFG(0) ; // set foreground to black
         }
@@ -61,17 +80,23 @@
     }
 }
 
+/** Filter out too little move 
+ * @param float in returned value from the acc
+ * @returns float result filtered value of in
+ */
 float filterVal(float in)
 {
     float result = 0.0 ;
-    if ((-0.2 < in)&&(in < 0.2)) {
-        result = 0.0 ;
-    } else {
+    if ((-threshold > in)||(in > threshold)) {
         result = in ;
     }
     return( result ) ;
 }
 
+/** Decide which direction to go
+ * @param float res[] acc value of x, y 
+ * @returns int direction to move 
+ */
 int getDirection(float res[])
 {
     float dx, dy ;
@@ -80,25 +105,26 @@
     dy = filterVal(res[1]) ;
 
     if ((dx*dx) > (dy*dy)) { // holizontal move
-        if (dx == 0.0) {
-            //
-        } else if (dx > 0.0) {
+        if (dx > 0.0) {
             direction = DIR_DOWN ;
-        } else {
+        } else if (dx < 0.0) {
             direction = DIR_UP ;
         }
     } else { // vertical move
-        if (dy == 0.0) {
-            //      
-        } else if (dy > 0) {
+        if (dy > 0.0) {
             direction = DIR_RIGHT ;
-        } else {
+        } else if (dy < 0.0) {
             direction = DIR_LEFT ;
         }
     }
     return(direction) ;
 }
 
+/** Get next positon to move to
+ * @param pos_type current where we are now
+ * @param int direction which way we'd like to move
+ * @returns the candidate positon for the next move
+ */
 pos_type getNext(pos_type current, int direction) 
 {
     pos_type next = current ;
@@ -118,7 +144,7 @@
     case DIR_RIGHT: 
         if (next.x < (MAZE_W - 1)) { 
             next.x++ ; 
-        } ; 
+        } 
         break ;
     case DIR_LEFT: 
         if (next.x > 0) { 
@@ -131,6 +157,21 @@
     return( next ) ;
 }
 
+/** Notice of the goal
+ */
+void showGoal(void)
+{
+    tty.blue() ;
+    tty.frame((MAZE_W/2)-4,(MAZE_H/2)-1,(MAZE_W/2)+4,(MAZE_H/2)+1) ;
+    tty.red() ;
+    tty.locate((MAZE_W/2)-3, (MAZE_H/2)) ;
+    printf("G O A L\n\r") ;
+}
+
+/** Check if we can move to the next position
+ * @param pos_type next the position we'd like to move next
+ * @returns if the position is empty (movable)
+ */
 bool checkMove(pos_type next) 
 {
     bool result = false ;
@@ -148,7 +189,9 @@
     } 
     return( result ) ;
 }
-    
+
+/** main a simple maze program
+ */
 int main() {
     float res[3] ;
     pos_type current, next, goal ;
@@ -156,36 +199,29 @@
     
     tty.cls() ;
     drawTextMaze(&current, &goal) ;
-    tty.locate(current.x+1, current.y+1) ;
     tty.black() ;
-    printf("@") ;
+    tty.putChar(current.x+1, current.y+1, '@') ;
     printf("\r\n") ;
     
     for (;;) {
         acc.getAccAllAxis(res) ;
         direction = getDirection(res) ;
         next = getNext(current, direction) ;
-        if (((next.x != current.x)||(next.y != current.y)) && checkMove(next)) {
-           tty.locate(current.x+1, current.y+1) ;
-            printf(" ") ;
-            tty.locate(next.x+1, next.y+1) ;
-            printf("@") ;
-            tty.green() ;
-            tty.locate(1, MAZE_H+1) ;
-            printf("\r\n") ;
-            tty.black() ;
-            current = next ;
-            if ((next.x == goal.x)&&(next.y == goal.y)) {
-                break ;
-            }
+        if ((!isSame(current, next)) && checkMove(next)) {
+           tty.putChar(current.x+1, current.y+1, ' ') ;
+           tty.putChar(next.x+1, next.y+1, '@') ;
+           tty.green() ;
+           tty.putStr(1, MAZE_H+1, "\r\n") ;
+           tty.black() ;
+           current = next ;
+           if (isSame(next, goal)) {
+             break ; // goal in!
+           }
         }
         wait(0.1) ;
     }
-    tty.blue() ;
-    tty.frame((MAZE_W/2)-4,(MAZE_H/2)-1,(MAZE_W/2)+4,(MAZE_H/2)+1) ;
-    tty.red() ;
-    tty.locate((MAZE_W/2)-3, (MAZE_H/2)) ;
-    printf("G O A L\n\r") ;
+    showGoal() ;
     for (;;) {
+        // wait for ever for reset
     }
 }