ELEC2645 (2019/20)
Final Submission. I have read and agreed with Statement of Academic Integrity.
Dependencies: mbed
Diff: main.cpp
- Revision:
- 9:b160a3de0d00
- Parent:
- 8:dc7b09f23d75
- Child:
- 10:4f204c2ac16c
diff -r dc7b09f23d75 -r b160a3de0d00 main.cpp
--- a/main.cpp Fri Jun 05 18:07:26 2020 +0000
+++ b/main.cpp Fri Jun 05 18:15:28 2020 +0000
@@ -2,11 +2,11 @@
#include "Gamepad.h"
#include "N5110.h"
-//Objects
+///Objects
Gamepad pad;
N5110 lcd;
-//initialise global variables to be used throughout the game
-//initial player position in all levels.
+///initialise global variables to be used throughout the game
+///initial player position in all levels.
char player_char = 'x';
int player_xpos = 8;
int player_ypos = 45;
@@ -20,15 +20,15 @@
int portal_2_xpos;
int portal_2_ypos;
-//initialise x direction movement
+///initialise x direction movement
int move = 0;
-//initialise terminators for menu and game loops.
+///initialise terminators for menu and game loops.
bool choice = false;
bool endgame = false;
-//initialise Game array
+///initialise Game array
char array[84][48];
-/*the characters in the level array's represent the following:
+/**the characters in the level array's represent the following:
'0' = air
'1' = right facing wall
'2' = floor
@@ -40,7 +40,7 @@
'Q' = portal 2
'x' = player
*/
-// level 1
+/// level 1
char _level_1[84][48] = {
{'3','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','2'},
{'3','0','0','0','0','0','0','0','0','0','2','3','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','2'},
@@ -127,7 +127,7 @@
{'3','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','1','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','2'},
{'3','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','2'},
};
- // level 3
+ /// level 3
char _level_3[84][48] = {
{'3','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','2'},
{'3','0','0','0','2','2','0','0','0','0','0','0','0','2','3','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','2','3','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','2'},
@@ -214,7 +214,7 @@
{'3','0','0','0','0','0','0','2','3','0','0','0','0','0','0','0','0','0','0','0','0','2','1','1','1','1','1','1','1','1','2','3','0','0','0','0','0','0','0','D','0','0','0','0','0','0','0','2'},
{'3','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','1','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','2'},
};
- // level 2
+ /// level 2
char _level_2[84][48] = {
{'3','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','4','2'},
{'3','0','0','0','2','2','0','0','0','0','0','0','0','2','3','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','2','0','0','0','0','0','2'},
@@ -303,7 +303,7 @@
};
-//Prototypes
+///Prototypes
void pad_init();
void update_display();
void apply_move();
@@ -316,14 +316,14 @@
void get_portal_angle();
void place_portal_1();
void place_portal_2();
-//Main function
+///Main function
int main()
{
-//initialise the pad
+///initialise the pad
pad_init();
- //loop until player has selected an option from the menu
+ ///loop until player has selected an option from the menu
while(choice == false) {
- //print welcome screen
+ ///print welcome screen
lcd.clear();
lcd.printString("Welcome to",0,0);
lcd.printString("2D Portal!",0,1);
@@ -332,7 +332,7 @@
lcd.printString("X = Level 2",0,4);
lcd.printString("Y = Level 3",0,5);
update_display();
- //cycle LED's whilst on home screen
+ ///cycle LED's whilst on home screen
pad.led(1,1);
wait(0.05);
pad.leds_off();
@@ -351,7 +351,7 @@
pad.led(6,1);
wait(0.05);
pad.leds_off();
- // print the controls for 5 seconds, then return to the menu screen.
+ /// print the controls for 5 seconds, then return to the menu screen.
if(pad.A_pressed() == 1){
lcd.clear();
lcd.printString("Joystick =Move",0,0);
@@ -365,70 +365,70 @@
wait_ms(5000);
choice = false;
}
- //loads level 1.
+ ///loads level 1.
else if(pad.B_pressed() == 1){
for(int i = 0; i < 84; i ++){
for(int j = 0; j < 48; j ++){
array[i][j] = _level_1[i][j];
choice = true;}}}
- //loads level 2
+ ///loads level 2
else if(pad.X_pressed() == 1){
for(int i = 0; i < 84; i ++){
for(int j = 0; j < 48; j ++){
array[i][j] = _level_2[i][j];
choice = true;}}}
- //loads level 3
+ ///loads level 3
else if(pad.Y_pressed() == 1){
for(int i = 0; i < 84; i ++){
for(int j = 0; j < 48; j ++){
array[i][j] = _level_3[i][j];
choice = true;}}}
- //refresh lcd to display chosen level when menu loop breaks.
+ ///refresh lcd to display chosen level when menu loop breaks.
lcd.refresh();
}
- //Loop runs until the player has solved the puzzle and exited the right hand side of the screen.
+ ///Loop runs until the player has solved the puzzle and exited the right hand side of the screen.
while(endgame == false){
- // converts joystick input into left or right movement.
+ /// converts joystick input into left or right movement.
get_move(move, pad);
- // checks to see if the move is valid and handles teleportation logic.
+ /// checks to see if the move is valid and handles teleportation logic.
collision_detection(move);
- // checks to see if the player has jumped, if they have then the players y pos will descrease by 1
+ /// checks to see if the player has jumped, if they have then the players y pos will descrease by 1
if(pad.A_pressed() == 1){
jump();
}
- //checks to see if the player has placed portal 1, if they have then the portal will be placed in the array
+ ///checks to see if the player has placed portal 1, if they have then the portal will be placed in the array
else if(pad.B_pressed() == 1){
place_portal_1();
- //turns on left red led to show portal 1 has been placed.
+ ///turns on left red led (LED1) to show portal 1 has been placed.
pad.led(1,1);
}
- //checks to see if the player has placed portal 2, if they have then the portal will be placed in the array
+ ///checks to see if the player has placed portal 2, if they have then the portal will be placed in the array
else if(pad.Y_pressed() == 1){
place_portal_2();
- //turns on right red led to show portal 2 has been placed.
+ ///turns on right red led (LED4) to show portal 2 has been placed.
pad.led(4,1);
}
else
- //handles setting the new position of the player in the array and erasing the previous player position from the array.
+ ///handles setting the new position of the player in the array and erasing the previous player position from the array.
apply_move();
- //prints to the lcd
+ ///prints to the lcd
print_screen();
- //refreshes the lcd to display the new screen after movement.
+ ///refreshes the lcd to display the new screen after movement.
update_display();
- // the objective of the game is to open the door and walk through it. as the door is on the right hand side of the screen, when the player
- // xpos exceeds 82, the puzzle is assumed to be solved as the door has to be opened to progress.
+ /// the objective of the game is to open the door and walk through it. as the door is on the right hand side of the screen, when the player
+ /// xpos exceeds 82, the puzzle is assumed to be solved as the door has to be opened to progress.
if(player_xpos > 82){
endgame = true;}
}
- //clear the level and print the win screen
+ ///clear the level and print the win screen
lcd.clear();
lcd.printString("Puzzle solved!",0,0);
lcd.printString("Press reset",0,0);
lcd.printString("To play again",0,0);
lcd.refresh();
}
-//initialise the game array with 0's
+///initialise the game array with 0's
void array_init(){
for(int j = 0; j < 48; j++){
for(int i = 0; i < 84; i++){
@@ -436,17 +436,17 @@
}}}
void apply_move(){
- // removes old player char in the array and increments the value of the player_xpos by the value in move
+ /// removes old player char in the array and increments the value of the player_xpos by the value in move
int old_player_xpos = player_xpos;
player_xpos += move;
array[old_player_xpos][player_ypos] = '0';
- //checks if the player is in the air, if they are then increase y by 1 until the player is on the floor and remove the old player char from the array
+ ///checks if the player is in the air, if they are then increase y by 1 until the player is on the floor and remove the old player char from the array
int old_player_ypos = player_ypos;
if(array[player_xpos][player_ypos+1] == '0'){
player_ypos += 1;
array[player_xpos][old_player_ypos] = '0';
}
- //checks if the player has landed on spikes and displays the end game screen with instructions for how to restart the game if they have.
+ ///checks if the player has landed on spikes and displays the end game screen with instructions for how to restart the game if they have.
else if(array[player_xpos][player_ypos+1] == 'S'){
lcd.clear();
lcd.printString("Spike hit!",0,0);
@@ -454,14 +454,14 @@
lcd.printString("Try again!",0,2);
lcd.refresh();
wait_ms(1000000000);
- //places the player char in the array
+ ///places the player char in the array
add_player_array();
}
}
-// converts the chars in the array to on or off pixels, dependant on the type of object in the array. i.e walls are a dark pixel and portals are a light pixel
-// this helps to distinguis where the portals are.
+/// converts the chars in the array to on or off pixels, dependant on the type of object in the array. i.e walls are a dark pixel and portals are a light pixel
+/// this helps to distinguis where the portals are.
void print_screen(){
for(int j = 0; j < 48; j++){
for(int i = 0; i < 84; i++){
@@ -488,9 +488,9 @@
lcd.setPixel(i,j, true);
}
}}
- // finds the position pot(2) is aiming at and prints the aim assist line
+ /// finds the position pot(2) is aiming at and prints the aim assist line
get_portal_angle();
- // prints the player sprite
+ /// prints the player sprite
lcd.setPixel(player_xpos,player_ypos-1, true);
lcd.setPixel(player_xpos-1,player_ypos-2, true);
lcd.setPixel(player_xpos-1,player_ypos-3, true);
@@ -504,7 +504,7 @@
-//initilise the pad and LCD
+///initilise the pad and LCD
void pad_init()
{
lcd.init();
@@ -512,14 +512,14 @@
lcd.clear();
pad.init();
}
-//places the player char in the array
+///places the player char in the array
void add_player_array()
{
array[player_xpos][player_ypos] = player_char;
}
-// takes the input from the joystick and converts it into left/rigth movments
+/// takes the input from the joystick and converts it into left/rigth movments
void get_move(int, Gamepad &pad)
{
char d = pad.get_direction();
@@ -534,61 +534,61 @@
}
-// refreshes the display with the updated game screen
+/// refreshes the display with the updated game screen
void update_display()
{
- lcd.refresh(); //Refreshes the lcd so the pixels appear
- wait_ms(150); //Frame rate of game
+ lcd.refresh(); ///Refreshes the lcd so the pixels appear
+ wait_ms(150); ///Frame rate of game
}
void collision_detection(int)
{
- //check if the player is moving into any object other than air. if they are then x direction movement = 0
+ ///check if the player is moving into any object other than air. if they are then x direction movement = 0
char dir = pad.get_direction();
if(array[player_xpos+1][player_ypos] != '0' && dir == E){
move = 0;}
else if(array[player_xpos-1][player_ypos] != '0' && dir == W){
move = 0;}
- // checks if the player is directly next to a portal and runs the logic to check where the player should be teleported to. This is dependant on the surfaces the second portal is placed on.
+ /// checks if the player is directly next to a portal and runs the logic to check where the player should be teleported to. This is dependant on the surfaces the second portal is placed on.
if(array[player_xpos+1][player_ypos] == 'P' || array[player_xpos-1][player_ypos] == 'P' || array[player_xpos][player_ypos-1] == 'P' || array[player_xpos][player_ypos+1] == 'P' ){
move = 0;
- // removes the old player char from the array
+ /// removes the old player char from the array
array[player_xpos][player_ypos] = '0';
- //logic for entering portal 1
- // if the position horizontally next to portal 2 is a '3' then portal 2 has been placed on a ceiling and the player must be placed below portal 2.
+ ///logic for entering portal 1
+ /// if the position horizontally next to portal 2 is a '3' then portal 2 has been placed on a ceiling and the player must be placed below portal 2.
if (array[portal_2_xpos-1][portal_2_ypos] == '3'){
player_xpos = portal_2_xpos;
player_ypos = portal_2_ypos+2;}
- // if the position horizontally next to portal 2 is a '2' then portal 2 has been placed on a floor and the player must be placed above and to the side of portal 2 so they dont fall back in.
+ /// if the position horizontally next to portal 2 is a '2' then portal 2 has been placed on a floor and the player must be placed above and to the side of portal 2 so they dont fall back in.
else if(array[portal_2_xpos-1][portal_2_ypos] == '2'){
player_xpos = portal_2_xpos + 1;
player_ypos = portal_2_ypos-1;}
- // if the position vertically next to portal 2 is a '1' then portal 2 has been placed on a right facing wall and the player must be placed on the left of portal 2.
+ /// if the position vertically next to portal 2 is a '1' then portal 2 has been placed on a right facing wall and the player must be placed on the left of portal 2.
else if(array[portal_2_xpos][portal_2_ypos - 1] == '1'){
player_xpos = portal_2_xpos - 2;
player_ypos = portal_2_ypos;}
- // if the position vertically next to portal 2 is a '4' then portal 2 has been placed on a left facing wall and the player must be placed on the right of portal 2.
+ /// if the position vertically next to portal 2 is a '4' then portal 2 has been placed on a left facing wall and the player must be placed on the right of portal 2.
else if(array[portal_2_xpos][portal_2_ypos - 1] == '4'){
player_xpos = portal_2_xpos + 2;
player_ypos = portal_2_ypos;}
}
- // logic for entering portal 2
+ /// logic for entering portal 2
else if(array[player_xpos+1][player_ypos] == 'Q' || array[player_xpos-1][player_ypos] == 'Q' || array[player_xpos][player_ypos-1] == 'Q' || array[player_xpos][player_ypos+1] == 'Q' ){
move = 0;
array[player_xpos][player_ypos] = '0';
- // if the position horizontally next to portal 1 is a '3' then portal 1 has been placed on a ceiling and the player must be placed below portal 1.
+ /// if the position horizontally next to portal 1 is a '3' then portal 1 has been placed on a ceiling and the player must be placed below portal 1.
if (array[portal_1_xpos-1][portal_1_ypos] == '3'){
player_xpos = portal_1_xpos;
player_ypos = portal_1_ypos+2;}
- // if the position horizontally next to portal 1 is a '2' then portal 1 has been placed on a floor and the player must be placed above and to the side of portal 1 so they dont fall back in.
+ /// if the position horizontally next to portal 1 is a '2' then portal 1 has been placed on a floor and the player must be placed above and to the side of portal 1 so they dont fall back in.
else if(array[portal_1_xpos-1][portal_1_ypos] == '2'){
player_xpos = portal_1_xpos + 1;
player_ypos = portal_1_ypos-1;}
- // if the position vertically next to portal 1 is a '1' then portal 1 has been placed on a right facing wall and the player must be placed on the left of portal 1.
+ /// if the position vertically next to portal 1 is a '1' then portal 1 has been placed on a right facing wall and the player must be placed on the left of portal 1.
else if(array[portal_1_xpos][portal_1_ypos - 1] == '1'){
player_xpos = portal_1_xpos - 2;
player_ypos = portal_1_ypos;}
- // if the position vertically next to portal 1 is a '4' then portal 1 has been placed on a left facing wall and the player must be placed on the right of portal 1.
+ /// if the position vertically next to portal 1 is a '4' then portal 1 has been placed on a left facing wall and the player must be placed on the right of portal 1.
else if(array[portal_1_xpos][portal_1_ypos - 1] == '4'){
player_xpos = portal_1_xpos + 2;
player_ypos = portal_1_ypos;}
@@ -598,16 +598,16 @@
- //removes the old player char from the array and replaces it with zero
+ ///removes the old player char from the array and replaces it with zero
erase_old_sprites(player_xpos, player_ypos);
- //checks if the player has stepped on the button, if they have then the button and door are replaced by air and the route to the exit is open.
+ ///checks if the player has stepped on the button, if they have then the button and door are replaced by air and the route to the exit is open.
if(array[player_xpos][player_ypos+1] == 'B'){
for(int i = 0; i < 84; i++){
for(int j = 0; j < 48; j++){
if(array[i][j] == 'D' || array[i][j] == 'B'){
array[i][j] = '0';}}}}
}
-// removes the old player character from the array.
+/// removes the old player character from the array.
void erase_old_sprites(char,char)
{
int old_player_xpos = player_xpos;
@@ -619,114 +619,114 @@
void jump()
-{ //if the space beneath the player = floor, then increase ypos by 1. Apply move causes the player to fall again shortly after on the next loop.
+{ ///if the space beneath the player = floor, then increase ypos by 1. Apply move causes the player to fall again shortly after on the next loop.
if(array[player_xpos][player_ypos+1] == '2'){
int old_player_ypos = player_ypos;
player_ypos += -1;
- //removes old player char from the array
+ ///removes old player char from the array
array[player_xpos][old_player_ypos] = '0';
}
}
-// next steps are to turn pot into degrees and make a function which chechks which pixel the pot is pointing at.
-// this function takes the pot(2) input range and converts it into 45 degree segments, after which the aim detector is sent out until it hits another object
+/// next steps are to turn pot into degrees and make a function which chechks which pixel the pot is pointing at.
+/// this function takes the pot(2) input range and converts it into 45 degree segments, after which the aim detector is sent out until it hits another object
void get_portal_angle()
{
- //take pot(2) val as a double to allow for more precise segments.
+ ///take pot(2) val as a double to allow for more precise segments.
double angle_input = pad.read_pot2();
- //position the player is aiming at
+ ///position the player is aiming at
aim_xpos = player_xpos;
aim_ypos = player_ypos;
- // if pot(2) is between 0 and 45 degrees, aim detection is projected at the floor,
+ /// if pot(2) is between 0 and 45 degrees, aim detection is projected at the floor,
if(angle_input > 0 && angle_input < 0.125){
- // The aim_ypos will increment until it is next to a surface that isnt the air.
+ /// The aim_ypos will increment until it is next to a surface that isnt the air.
while(array[aim_xpos][aim_ypos + 1] == '0'){
aim_ypos = player_ypos + 1;
}
- // increment once more to place portal in the surface
+ /// increment once more to place portal in the surface
aim_ypos = player_ypos + 1;
}
- // if pot(2) is between 45 and 90 degrees, aim detection is diagonally down left
+ /// if pot(2) is between 45 and 90 degrees, aim detection is diagonally down left
else if(angle_input > 0.125 && angle_input < 0.25){
while(array[aim_xpos -1 ][aim_ypos + 1] == '0'){
- // performs relevant increments and decrements for downward diagonal left movement.
+ /// performs relevant increments and decrements for downward diagonal left movement.
aim_xpos += - 1;
aim_ypos += 1;
}
- // performs increments and decrements once more to place portal in the surface
+ /// performs increments and decrements once more to place portal in the surface
aim_xpos += - 1;
aim_ypos += 1;
}
- // if pot(2) is between 90 and 135 degrees, aim detection is projected towards the left
+ /// if pot(2) is between 90 and 135 degrees, aim detection is projected towards the left
else if(angle_input > 0.25 && angle_input < 0.375){
while(array[aim_xpos -1 ][aim_ypos] == '0'){
- // The aim_xpos will decrement until it is next to a surface that isnt the air.
+ /// The aim_xpos will decrement until it is next to a surface that isnt the air.
aim_xpos += - 1;
}
- // decrement once more to place portal in the surface
+ /// decrement once more to place portal in the surface
aim_xpos += - 1;
}
- // if pot(2) is between 135 and 180 degrees, aim detection is diagonally up left
+ /// if pot(2) is between 135 and 180 degrees, aim detection is diagonally up left
else if(angle_input > 0.375 && angle_input < 0.5){
while(array[aim_xpos -1 ][aim_ypos-1] == '0'){
- // performs relevant decrements for upward diagonal left movement.
+ /// performs relevant decrements for upward diagonal left movement.
aim_xpos += - 1;
aim_ypos += - 1;
}
- // performs decrements once more to place portal in the surface
+ /// performs decrements once more to place portal in the surface
aim_xpos += - 1;
aim_ypos += -1;
}
- // if pot(2) is between 180 and 225 degrees, aim detection is upwards
+ /// if pot(2) is between 180 and 225 degrees, aim detection is upwards
else if(angle_input > 0.5 && angle_input < 0.625){
while(array[aim_xpos][aim_ypos-1] == '0'){
- // The aim_ypos will decrement until it is next to a surface that isnt the air.
+ /// The aim_ypos will decrement until it is next to a surface that isnt the air.
aim_ypos += - 1;
}
- // decrement once more to place portal in the surface
+ /// decrement once more to place portal in the surface
aim_ypos += -1;
}
- // if pot(2) is between 225 and 270 degrees, aim detection is diagonally up right
+ /// if pot(2) is between 225 and 270 degrees, aim detection is diagonally up right
else if(angle_input > 0.625 && angle_input < 0.75){
while(array[aim_xpos+1][aim_ypos-1] == '0'){
- // performs relevant increments and decrements for downward diagonal left movement.
+ /// performs relevant increments and decrements for downward diagonal left movement.
aim_ypos += - 1;
aim_xpos += 1;
}
- // performs increments and decrements once more to place portal in the surface.
+ /// performs increments and decrements once more to place portal in the surface.
aim_ypos += -1;
aim_xpos += 1;
}
- // if pot(2) is between 270 and 315 degrees, aim detection is to the right
+ /// if pot(2) is between 270 and 315 degrees, aim detection is to the right
else if(angle_input > 0.75 && angle_input < 0.875){
while(array[aim_xpos+1][aim_ypos] == '0'){
- // The aim_xpos will increment until it is next to a surface that isnt the air.
+ /// The aim_xpos will increment until it is next to a surface that isnt the air.
aim_xpos += 1;
}
- // The aim_xpos will increment once more to place the portal in the surface.
+ /// The aim_xpos will increment once more to place the portal in the surface.
aim_xpos += 1;
}
- // if pot(2) is between 315 and 360 degrees, aim detection is diagonally down right
+ /// if pot(2) is between 315 and 360 degrees, aim detection is diagonally down right
else if(angle_input > 0.875 && angle_input < 1){
while(array[aim_xpos+1][aim_ypos + 1] == '0'){
- // performs relevant increments for downward diagonal left movement.
+ /// performs relevant increments for downward diagonal left movement.
aim_xpos += 1;
aim_ypos += 1;
}
- // performs increments once more to place portal in the surface
+ /// performs increments once more to place portal in the surface
aim_xpos += 1;
aim_ypos += 1;
}
- // draw the aim assist dashed line to give a visual representation of where the player is aiming the portal gun
- // this code allows for dynamic drawing of the aim assist relevant to the players position and the aim direction given by the potentiometer
+ /// draw the aim assist dashed line to give a visual representation of where the player is aiming the portal gun
+ /// this code allows for dynamic drawing of the aim assist relevant to the players position and the aim direction given by the potentiometer
lcd.drawLine((player_xpos),(player_ypos), aim_xpos,aim_ypos,2);
lcd.refresh();
}
-//removed the old portal 1 and places the new one where the aim assist is pointed.
+///removed the old portal 1 and places the new one where the aim assist is pointed.
void place_portal_1()
{
int old_p1_xpos = portal_1_xpos;
@@ -736,7 +736,7 @@
portal_1_ypos = aim_ypos;
array[portal_1_xpos][portal_1_ypos] = 'P';}
-//removed the old portal 2 and places the new one where the aim assist is pointed.
+///removed the old portal 2 and places the new one where the aim assist is pointed.
void place_portal_2()
{
int old_p2_xpos = portal_2_xpos;