Blinker

implement simple, fast computer players
Parent da21aee
Stefan Schuermans

Stefan Schuermans commited on 2019-06-10 18:25:59
Showing 2 changed files, with 72 additions and 0 deletions.

src/common/Pong.cpp
View file @ ae99ab3
... ... 
@@ -108,6 +108,10 @@ void Pong::redraw()
108 108 
 /// callback when requested time reached
109 109 
 void Pong::timeCall()
110 110 
 {
111 
+  // computer player: move pads
112 
+  computerLeft();
113 
+  computerRight();
114 
+
111 115 
   // bounce ball
112 116 
   bounceBall();
113 117
... ... 
@@ -122,6 +126,68 @@ void Pong::timeCall()
122 126 
   planTimeCall();
123 127 
 }
124 128
129 
+/// computer player for left pad
130 
+void Pong::computerLeft()
131 
+{
132 
+  // ball not moving towards pad: do not move
133 
+  if (m_ballDirX >= 0) {
134 
+    return;
135 
+  }
136 
+
137 
+  // compute expected ball position at pad
138 
+  int expectedY = m_ballPosY + (m_ballPosX - 1) * m_ballDirY;
139 
+
140 
+  // compute pad position to hit ball with center of pad
141 
+  int padY = expectedY - m_padSize / 2;
142 
+
143 
+  // do not move pad out of field
144 
+  if (padY < 0) {
145 
+    padY = 0;
146 
+  }
147 
+  if (padY > m_height - m_padSize) {
148 
+    padY = m_height - m_padSize;
149 
+  }
150 
+
151 
+  // move pad
152 
+  if (m_leftPosY < padY) {
153 
+    ++m_leftPosY;
154 
+  }
155 
+  else if (m_leftPosY > padY) {
156 
+    --m_leftPosY;
157 
+  }
158 
+}
159 
+
160 
+/// computer player for right pad
161 
+void Pong::computerRight()
162 
+{
163 
+  // ball not moving towards pad: do not move
164 
+  if (m_ballDirX <= 0) {
165 
+    return;
166 
+  }
167 
+
168 
+  // compute expected ball position at pad
169 
+  int expectedY = m_ballPosY + (m_width - 2 - m_ballPosX) * m_ballDirY;
170 
+
171 
+  // compute pad position to hit ball with center of pad
172 
+  int padY = expectedY - m_padSize / 2;
173 
+
174 
+  // do not move pad out of field
175 
+  if (padY < 0) {
176 
+    padY = 0;
177 
+  }
178 
+  if (padY > m_height - m_padSize) {
179 
+    padY = m_height - m_padSize;
180 
+  }
181 
+
182 
+  // move pad
183 
+  if (m_rightPosY < padY) {
184 
+    ++m_rightPosY;
185 
+  }
186 
+  else if (m_rightPosY > padY) {
187 
+    --m_rightPosY;
188 
+  }
189 
+}
190 
+
125 191 
 /// bounce ball
126 192 
 void Pong::bounceBall()
127 193 
 {
src/common/Pong.h
View file @ ae99ab3
... ... 
@@ -61,6 +61,12 @@ protected:
61 61 
   /// callback when requested time reached
62 62 
   virtual void timeCall();
63 63
64 
+  /// computer player for left pad
65 
+  void computerLeft();
66 
+
67 
+  /// computer player for right pad
68 
+  void computerRight();
69 
+
64 70 
   /// bounce ball
65 71 
   void bounceBall();
66 72
67 73