From aea9a53762c03205db229c63505b48a41bf86688 Mon Sep 17 00:00:00 2001
From: orange <mike@sprachgewalt.de>
Date: Sat, 15 Jun 2013 22:26:40 +0200
Subject: [PATCH] paddles!

---
 ncurses-pong.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/ncurses-pong.c b/ncurses-pong.c
index 06e806c..e2d5f96 100644
--- a/ncurses-pong.c
+++ b/ncurses-pong.c
@@ -13,19 +13,37 @@ void xy2rc(float x, float y, int *r, int *c) {
   *r = MAX_R - ((y / MAX_Y) * MAX_R);
 }
 
+float lerp(float from, float to, float t) {
+  return from + t * (to-from);
+}
+
 float ball_x = 0.0;
 float ball_y = 0.0;
 float dir_x = +2.0;
 float dir_y = +1.0;
 
+float pad_l = 0.0;
+float pad_r = 0.0;
+
 void paint_ball() {
   int r, c;
   xy2rc(ball_x, ball_y, &r, &c);
   mvaddch(r, c, ACS_DIAMOND);
 }
 
+void paint_paddles() {
+  int r, c;
+  xy2rc(    0, pad_l, &r, &c);
+  mvaddch(r, c, ACS_VLINE);
+
+  xy2rc(MAX_X, pad_r, &r, &c);
+  c--;
+  mvaddch(r, c, ACS_VLINE);
+}
+
 void paint() {
   clear();
+  paint_paddles();
   paint_ball();
 
   refresh();
@@ -46,6 +64,14 @@ int main() {
       dir_y = -dir_y;
     }
 
+    /* Awesome artificial intelligence working here. */
+    if (ball_x < 0.25f * MAX_X) {
+      pad_l = lerp(pad_l, ball_y, 0.3);
+    }
+    if (ball_x > 0.75f * MAX_X) {
+      pad_r = lerp(pad_r, ball_y, 0.3);
+    }
+
     paint();
     usleep(50000);
   }