Diff: Engine/Engine.cpp

Revision:

26:4253656c0755

Parent:

23:ff9073e12106

Child:

27:c920c5ec31af

--- a/Engine/Engine.cpp	Wed Apr 24 17:58:35 2019 +0000
+++ b/Engine/Engine.cpp	Fri May 03 09:33:34 2019 +0000
@@ -1,7 +1,8 @@
 #include "Engine.h"
 
 // Reference for the technique used to generate random numbers.
-// [1] "rand" cplusplus. [Online] Available: http://www.cplusplus.com/reference/cstdlib/rand/ [Accessed: 22 April 2019]. 
+// [1] "rand" cplusplus. [Online] Available: 
+// http://www.cplusplus.com/reference/cstdlib/rand/ [Accessed: 22 April 2019]. 
 
 // Buffer to print updated score.
 char buffer[14];   
@@ -20,15 +21,17 @@
 void Engine::check_reset(N5110 &lcd, Gamepad &gamepad) {
   // If reset flag is true, end and restart the game.
   if (_skater.get_reset_flag()) {
+    gamepad.leds_on();
     execute_dying_sequence(lcd, gamepad);
-    wait(1);
+    wait(1);  // Short pause.
     reset_skater();
     reset_engine();
   }
 }
 
 void Engine::execute_dying_sequence(N5110 &lcd, Gamepad &gamepad) {
-  wait(1);
+  wait(1);  // Short pause.
+  gamepad.leds_off();
   lcd.clear();
   for (int i = 0; i < 40; i = i + 8) {  // Counter for y direction, sweeps top 
   // to bottom.
@@ -38,8 +41,8 @@
       lcd.printString("TRY AGAIN",30,5);  
       lcd.refresh();
       gamepad.tone(int(1099 - 15.4*j - 1.2*i), 0.05);  // Frequnecy of tone is 
-      // dependent on counters. 
-      wait(0.001);
+      // dependent on counters.
+      wait(0.001);  // Control speed of the sequence.
       sprintf(buffer,"%2d",_player_score); 
       lcd.printString(buffer,0,5);
     }  
@@ -51,7 +54,7 @@
   _start_platform_flag = true;  // For printing start text in EngineController.
   _skater.set_reset_flag(false);
   _moving_counter = 0;
-  _jump_counter = 20; 
+  _jump_counter = 20;  // Start game falling onto the platform. 
   _fall_flag = false;
 }  
 
@@ -65,16 +68,18 @@
   _fire.init();
   _coin_collision_flag = false;
   _player_score = 0;
+  _fire_height = 0;
 }  
 
 void Engine::read_input(Gamepad &gamepad) {
+  // Set up the input struct.
   _input.coord = gamepad.get_mapped_coord(); 
   _input.A_flag = gamepad.check_event(Gamepad::A_PRESSED);
 } 
 
 void Engine::process_y(Gamepad &gamepad) {
   // Sets the y coord by first checking if the skater should be falling.
-  set_fall_flag();
+  set_fall_flag();  // Update the fall flag dependent on skater position.
   if (_fall_flag) {
     _skater.fall(_fall_flag, gamepad);
   } else {
@@ -88,15 +93,19 @@
 
 void Engine::set_fall_flag() {
   // Set the fall flag to true if the skater is not on one of the lower 
-  // platforms.
+  // platforms. The start platform condition has been offset by 6 to account for 
+  // skater sprite size.
+  // If the skater is between platform 1 and 2, and on the lower level. 
   if (((_lower_line_1.x_end < _skater_x) 
       && (_skater_x < (_lower_line_2.x_start - 6)))  
-      && _skater_y == 23) {
+      && _skater_y == 23) {  
     _fall_flag = true; 
+  // If the skater is between platforms 2 and 3, and on the lower level.  
   } else if (((_lower_line_2.x_end < _skater_x) 
              && (_skater_x < (_lower_line_3.x_start - 6))) 
              && _skater_y == 23) {
     _fall_flag = true;
+  // If the skater is between platforms 3 and 1, and on the lower level.  
   } else if (((_lower_line_3.x_end < _skater_x) 
              && (_skater_x < (_lower_line_1.x_start - 6))) 
              && _skater_y == 23) {
@@ -112,9 +121,11 @@
     _input.coord.y);
   _skater_x = _skater.get_x_position();
   _moving_counter = _skater.get_moving_counter();  // Update moving counter.
-  _speed_divider = int(-0.05*_player_score + 4);
+  _speed_divider = int(-0.05*_player_score + 4);  // Speed divider is calculated
+  // from player score.
+  // Move the skater along with platforms at rate determined by speed divider if
+  // the skater is not moving left.
   if ((game_counter % _speed_divider == 0) && (_input.coord.x > -0.1)) {  
-  // Move the skater along with platforms at rate determined by speed divider.
     _moving_counter--;
   }
 }
@@ -128,13 +139,17 @@
 
 void Engine::set_level_condition() {
   // If the skater is under or on top of any of the upper platforms, set
-  // level condition to 1.
+  // level condition to 1. 
+  // Offset of 6 is to account for sprite size.
+  // If the skater is between start and end of upper platform 1.  
   if (((_upper_line_1.x_start - 6) <= _skater_x) 
       && (_skater_x <= _upper_line_1.x_end)) {
     _level_condition = 1; 
+  // If the skater is between start and end of upper platform 2. 
   } else if (((_upper_line_2.x_start - 6) <= _skater_x) 
              && (_skater_x <= _upper_line_2.x_end)) {
     _level_condition = 1;
+  // If the skater is between start and end of upper platform 3.   
   } else if (((_upper_line_3.x_start - 6) <= _skater_x) 
              && (_skater_x <= _upper_line_3.x_end)) {
     _level_condition = 1;
@@ -144,21 +159,50 @@
 }
     
 void Engine::generate_level(int game_counter) {
+  // Generate properties for the level.
   generate_lower_lines();
   generate_upper_lines();
   _coin.generate_coin();
   generate_fire(game_counter);
 }
 
+void Engine::draw_screen_fire(int game_counter, N5110 &lcd) {
+  // Prints the dynamic fire at the bottom of the screen.
+  // Restricts the max fire height multiplier, which is dependent on player 
+  // score. 
+  if (_player_score < 15) {
+    _fire_height = _player_score;
+  } else {
+    _fire_height = 14;
+  }
+  // i corresponds to horizontal positions of pixels.
+  for (int i = 1; i < 84; i++) {
+    if (i % 4 == 0) {
+      // j corresponds to vertical height of pixels, and the max height is
+      // dependent on game counter (0 to 99) so changes every loop, and is 
+      // scaled.
+      for (int j = 0; j < game_counter*0.01*_fire_height; j++) {
+        lcd.setPixel(i + (rand() % 8 + 1) ,50 - j*1.3,true);  // Horizontal 
+        // position of pixel is constrained random [1], multiplier on j varies 
+        // local height. 
+        lcd.setPixel(i - (rand() % 8 + 1) ,50 - j*1.2,true);  // [1].
+        lcd.setPixel(i - (rand() % 8 + 1) ,50 - j*1.6,true);  // [1].
+        lcd.setPixel(i + (rand() % 8 + 1) ,50 - j*1.1,true);  // [1].
+        lcd.setPixel(i - (rand() % 8 + 1) ,50 - j*1.4,true);  // [1].
+      }  
+    }
+  }    
+}
+
 void Engine::generate_lower_lines() {
   // Use a scaled random number to generate the length of the lower lines.
-  _length_1 = (rand() %20) + 10; // [1].   
+  _length_1 = (rand() %20) + 10;  // [1].   
   _lower_platforms.set_line_1(_length_1);
   _lower_line_1 = _lower_platforms.get_line_1(); 
-  _length_2 = (rand() %20) + 10; // [1].      
+  _length_2 = (rand() %20) + 10;  // [1].      
   _lower_platforms.set_line_2(_length_2);
   _lower_line_2 = _lower_platforms.get_line_2();
-  _length_3 = (rand() %20) + 10; // [1].      
+  _length_3 = (rand() %20) + 10;  // [1].      
   _lower_platforms.set_line_3(_length_3);
   _lower_line_3 = _lower_platforms.get_line_3();
 }
@@ -177,11 +221,12 @@
 void Engine::generate_fire(int game_counter) {
   // Generates the x and y coordinate of the fire. Y oscillates from 5 to 23.
   _fire.generate_fire(); // Generates X coord of fire.
+  // Y is calculated from parabolic relation to game counter.
   _fire_y = int(-0.0073*game_counter*game_counter + 0.73*game_counter + 5);  
-  // Y is calculated from parabolic relation to game counter. 
 }
 
-void Engine::update_lcd(N5110 &lcd){
+void Engine::update_lcd(N5110 &lcd, int game_counter){
+  // Draw all sprites, screen fire, platforms and player score. 
   lcd.drawSprite(_skater_x,_skater_y,17,10,
                 (int *)_skater.get_sprite(_skater_sprite));
   lcd.drawSprite(_coin.get_coin_x(),_coin.get_coin_y(),5,5,
@@ -201,36 +246,41 @@
                _upper_line_3.y,FILL_BLACK);
   sprintf(buffer,"%2d",_player_score);
   lcd.printString(buffer,0,0);
+  draw_screen_fire(game_counter, lcd);
 }
 
 bool Engine::get_start_platform_flag() {
-  if (_input.A_flag) _start_platform_flag = false;  // Means starting platform 
-  // will vanish after first jump of the game.
+  if (_input.A_flag) _start_platform_flag = false;  // Makes starting platform 
+  // vanish after first jump of the game.
   return _start_platform_flag;
 }
 
 void Engine::check_coin_collision(Gamepad &gamepad) {
+  // If skater x and y coord matches the coin's. Small adjustment for Y coord
+  // compensates for skater sprite size.
   if (_skater_x == _coin.get_coin_x() 
-      && (_skater_y == _coin.get_coin_y() - 10)) {  // Small adjustment for Y 
-  // coord compensates for skater sprite size.
+      && (_skater_y == _coin.get_coin_y() - 10)) {  
     _coin_collision_flag = true;
     _player_score++;
     _coin.set_coin((rand() % 100),(abs(rand() % 100 - 20)));  // Place coin 
     // on a constrained random position, [1].
-    gamepad.tone(1500, 0.05);  // Make noise on buzzer.
+    gamepad.tone(1500, 0.05);  // Make collection noise on buzzer.
     wait(0.05);
     gamepad.tone(3000, 0.05);   
   }
 }
 
-void Engine::check_fire_collision(Gamepad &gamepad) {
+void Engine::check_fire_collision(Gamepad &gamepad, int game_counter) {
+  // If skater is not ducking, has same x coord and within a range of y coord 
+  // as fire.
   if (_input.coord.y > -0.1 
       && _skater_x == _fire.get_fire_x() 
       && _skater_y > _fire_y - 10 
-      && _skater_y < _fire_y + 10) {  // If skater is not ducking. A range of Y 
-  // coords to make collision more frequent.
+      && _skater_y < _fire_y + 10
+      ) {  // A range of Y coords to make collision 
+  // more frequent.
     _skater.set_reset_flag(true);
-    gamepad.tone(400, 0.25); // Make noise on buzzer.
+    gamepad.tone(400, 0.25); // Make collision noise on buzzer.
     wait(0.05);
     gamepad.tone(200, 0.25);
   } else if ( _skater_x < -10 || _skater_x > 84 ) { // If skater goes off the 
@@ -238,6 +288,11 @@
     _skater.set_reset_flag(true);
     gamepad.tone(200, 0.5);
   }
+  // If the skater collides with the scaled peak of the background fire. 
+  if (_skater_y > (50 - game_counter*_fire_height*0.023)) {
+    _fall_flag = true;
+    wait(0.05);  // Slow down falling sequence. 
+  } 
 }
 
 int Engine::get_player_score() {