bouncing ball

bouncing_ball.c

+/**
+ * bouncing ball
+ */
+#include <graphics.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+int kbhit()
+{
+    struct timeval tv;
+    fd_set fds;
+    tv.tv_sec = 0;
+    tv.tv_usec = 0;
+    FD_ZERO(&fds);
+    FD_SET(STDIN_FILENO, &fds); //STDIN_FILENO is 0
+    select(STDIN_FILENO+1, &fds, NULL, NULL, &tv);
+    return FD_ISSET(STDIN_FILENO, &fds);
+}
+
+int main()
+{
+
+    /* request autodetection */
+    int gdriver = DETECT, gmode, errorcode;
+    /* Local Variables */
+    int x, y;
+    int up = 0;
+    int left = 0;
+
+    /* initialize graphics and local variables */
+    initgraph(&gdriver, &gmode, "");
+
+    /* get mid positions in x and y-axis */
+    x = getmaxx() / 2;
+    y = getmaxy() / 2;
+
+    while (!kbhit()) {
+        if (y >= getmaxy() - 30)
+            up = 1;
+        if (y <= 30)
+            up = 0;
+
+        if (x >= getmaxx() - 30)
+            left = 1;
+        if (x <= 30)
+            left = 0;
+
+        setcolor(RED);
+        circle(x, y, 30);
+        floodfill(x, y, RED);
+
+        /* prepare for next  frame */
+        delay(15);
+        cleardevice();
+
+        if (up)
+            y = y - 5;
+        else
+            y = y + 5;
+
+        if (left)
+            x = x - 5;
+        else
+            x = x + 5;
+    }
+
+    /* clean up */
+    closegraph();
+    return 0;
+}

line.c

@@ -87,6 +87,7 @@ int main()
 
    /* request autodetection */
    int gdriver = DETECT, gmode, errorcode;
+   /* Local Variables */
    int xmax, ymax;
 
    /* initialize graphics and local variables */