Platformer - Only scroll the platforms help.

[DJLad16]

I need to make so just that the platforms I have scroll left or right, not the background as well.
How can I achieve this?
(I've had to removed most of the functions due to character limit).

#include <allegro5/allegro.h>
#include <allegro5/allegro_native_dialog.h>
#include <allegro5/allegro_font.h>
#include <allegro5/allegro_ttf.h>
#include <allegro5/allegro_primitives.h>
#include <allegro5/allegro_image.h>
#include <allegro5/allegro_audio.h>
#include<allegro5/allegro_acodec.h>
#include <cstdlib>
#include <ctime>
#include "objects.h"

#define ScreenWidth 800
#define ScreenHeight 600

//Prototpyes
void initPlayer(Player &player);

void initCoin(Coin &coin1);
void drawCoin(Coin &coin1, ALLEGRO_BITMAP *image);
bool coinCollide(Coin &coin1,Player &player ,int cX, int cY, int cWidth, int cHeight, int pWidth, int pHeight, bool live, int coinCount);

void initCoin2(Coin &coin2);
void drawCoin2(Coin &coin2, ALLEGRO_BITMAP *image);
bool coinCollide2(Coin &coin2,Player &player ,int cX, int cY, int cWidth, int cHeight, int pWidth, int pHeight, bool live, int coinCount);

void initArrow(Arrow arrow[], int size);
void drawArrow(Arrow arrow[], int size);
void fireArrow(Arrow arrow[], int size, Player &player, ALLEGRO_SAMPLE *bowShot);
void updateArrow(Arrow arrow[], int size);

bool collision(Player &player, int ex, int ey, int eWidth, int eHeight, int pWidth, int pHeight);

void cameraUpdate(float *cameraPosition,Player &player, int width, int height);

//Global Variables
enum direction {LEFT, RIGHT};
int dir = LEFT;
int arrowCount = 10;
//const int NUM_ARROW = 10;
const int NUM_ENEMY = 10;
int groundHeight = 545;
static bool fired = false;
bool coinLive = false;

int main()
{
	srand(static_cast<unsigned int>(time(0)));
	
	al_set_new_display_option(ALLEGRO_DEPTH_SIZE, 24, ALLEGRO_REQUIRE);
	ALLEGRO_DISPLAY *display;

	if(!al_init())
	{
		al_show_native_message_box(NULL, NULL, "Error", "Falied to initialize allegro", NULL, NULL);
		return -1;
	}
	
	display = al_create_display(ScreenWidth, ScreenHeight);

	if(!display)
	{
		al_show_native_message_box(NULL, NULL, "Error", "Falied to initialize the display", NULL, NULL);
		return -1;
	}

	Player player;
	Coin coin1;
	Coin coin2;
	Arrow arrow[10];
	bool done = false, active = false, draw = true;
	bool jump = false;
	int sourceX = 32, sourceY = 0;
	int coinCount = 0;
	const float FPS = 55.0;
	float jumpSpeed = 16.5;
	float velX = 0, velY = 0;
	const float gravity = 1;
	float cameraPosition[2] = {0,0};

	al_init_image_addon();
	al_init_primitives_addon();
	al_install_keyboard();
	al_init_font_addon();
	al_init_ttf_addon();
	al_install_audio();
	al_init_acodec_addon();

	initPlayer(player);
	initArrow(arrow, 10);
	initCoin(coin1);
	initCoin2(coin2);

	ALLEGRO_KEYBOARD_STATE keystate;
	ALLEGRO_TRANSFORM camera;
	ALLEGRO_SAMPLE *coinCollect = al_load_sample("coin collect sound.wav");
	ALLEGRO_SAMPLE *bowShot = al_load_sample("bow sound effect.wav");
	ALLEGRO_BITMAP *character = al_load_bitmap("spritesheet(Bow & left + right).png");
	ALLEGRO_BITMAP *background = al_load_bitmap("ayers rock.png");
	ALLEGRO_BITMAP *coin = al_load_bitmap("coin2.png");
	ALLEGRO_BITMAP *ground = al_load_bitmap("Ground.png");
	ALLEGRO_BITMAP *platform = al_load_bitmap("platform(long).png");
	ALLEGRO_BITMAP *platform2 = al_load_bitmap("platform(short).png");
	ALLEGRO_FONT *numArrow = al_load_font("JUNGBN__.TTF", 23, 0);
	ALLEGRO_FONT *numCoin = al_load_font("JUNGBN__.TTF", 23, 0);
	ALLEGRO_TIMER *timer = al_create_timer(1.0/FPS);
	ALLEGRO_EVENT_QUEUE *event_queue = al_create_event_queue();

	al_reserve_samples(2);
	al_set_window_title(display, "Australian Outback");
	al_register_event_source(event_queue, al_get_keyboard_event_source());
	al_register_event_source(event_queue, al_get_timer_event_source(timer));
	al_register_event_source(event_queue, al_get_display_event_source(display));

	al_start_timer(timer);
	while(!done)
	{
		ALLEGRO_EVENT event;
		al_wait_for_event(event_queue, &event);
		al_get_keyboard_state(&keystate);
			
		if(al_key_down(&keystate, ALLEGRO_KEY_ESCAPE))
		{
			done = true;
		}
		else if(event.type == ALLEGRO_EVENT_DISPLAY_CLOSE)
		{
			done = true;
		}
		
		
		else if(event.type == ALLEGRO_EVENT_TIMER)
		{
			active = true;
			updateArrow(arrow, 10);

			if(al_key_down(&keystate, ALLEGRO_KEY_D))
			{
				velX = player.speed;
				dir = RIGHT;
				
			}
			else if(al_key_down(&keystate, ALLEGRO_KEY_A))
			{
				velX = -player.speed;
				dir = LEFT;
			}
			else 
			{
				velX = 0;
				active = false;
			}
			if(al_key_down(&keystate, ALLEGRO_KEY_W) && jump)
			{
				velY = -jumpSpeed;
				jump = false;
			}
			if(active)
			{
				sourceX += al_get_bitmap_width(character) / 3;
			}
			else 
			{
				sourceX = 32; 
			}
			if(sourceX >= al_get_bitmap_width(character))
			{
				sourceX = 0;
			}
				sourceY = dir;
					draw = true;
			if(!jump)
				velY += gravity;
			else
				velY = 0;
				player.x += velX;
				player.y += velY;
			
			jump = (player.y >= groundHeight);

			if(jump)
			{
				player.y = groundHeight;
			}

			cameraUpdate(cameraPosition, player, 32, 32);
			al_identity_transform(&camera);
			al_translate_transform(&camera, -cameraPosition[0], -cameraPosition[1]);
			al_use_transform(&camera);

		}
		
		if(al_key_down(&keystate, ALLEGRO_KEY_SPACE))
		{
			fireArrow(arrow, 10, player, bowShot);
		}
		else
		{
			fired = false;
		}
		if(collision(player, 360, 447, 351, 30, 32, 32))
		{
			groundHeight = 435;
			player.y = groundHeight;
		
		}	
		else if(collision(player, 70, 377, 214, 38, 32, 32))
		{
			groundHeight = 365;
			player.y = groundHeight;
		}
		else
		{
			groundHeight = 545;
		}
		
		if(coinCollide(coin1, player, coin1.x, coin1.y, coin1.width, coin1.height, 32, 32, coinLive, coinCount))
		{
			coin1.live = false;
			++coinCount;
			coin1.x = 0;
			coin1.y = 0;
			al_play_sample(coinCollect, 1.0, 0.0, 1.0, ALLEGRO_PLAYMODE_ONCE, 0);
		}
		if(coinCollide2(coin2, player, coin2.x, coin2.y, coin2.width, coin1.height, 32, 32, coinLive, coinCount))
		{
			coin2.live = false;
			++coinCount;
			coin2.x = 0;
			coin2.y = 0;
			al_play_sample(coinCollect, 1.0, 0.0, 1.0, ALLEGRO_PLAYMODE_ONCE, 0);
		}
		
	if(draw && al_is_event_queue_empty(event_queue))
	{
		draw = false;
		al_draw_bitmap_region(character, sourceX, sourceY * al_get_bitmap_height(character) / 2, 32, 32, player.x, player.y, NULL);
		drawArrow(arrow,10);
		drawCoin(coin1, coin);
		drawCoin2(coin2, coin);
		al_draw_textf(numArrow, al_map_rgb(252,209, 22), 10, 10, 0, "Arrows: %i", arrowCount);
		al_draw_textf(numCoin, al_map_rgb(252, 209, 22), 10, 50, 0, "Coins: %i", coinCount);
		al_flip_display();
		al_clear_to_color(al_map_rgb(255, 255, 255));
		al_draw_bitmap(background, 0,0, 0);
		al_draw_bitmap(ground, 0, 549, 0);
		al_draw_bitmap(platform, 360, 447, NULL);
		al_draw_bitmap (platform2, 70, 377, NULL);
		
	}
  }

	al_destroy_bitmap(character);
	al_destroy_bitmap(ground);
	al_destroy_bitmap(coin);
	al_destroy_bitmap(platform);
	al_destroy_sample(coinCollect);
	al_destroy_font(numArrow);
	al_destroy_display(display);
	al_destroy_event_queue(event_queue);
	al_destroy_timer(timer);
	return 0;
}
void initPlayer(Player &player)
{
	player.x = 10;
	player.y = 545;
	player.ID = PLAYER;
	player.lives = 3;
	player.speed = 5;
	player.score = 0;
}
bool collision(Player &player, int ex, int ey, int eWidth, int eHeight, int pWidth, int pHeight)
{
	if((player.x > ex + eWidth - 10) || (player.y > ey + eHeight - 10) ||
		(ex > player.x + pWidth - 10) || (ey > player.y + pHeight - 10))
	{
		return false;
	}
	return true;
}

void cameraUpdate(float *cameraPosition, Player &player, int width, int height)
{
	cameraPosition[0] = -(ScreenWidth / 2) + (player.x + width / 2);
	cameraPosition[1] = -(ScreenHeight / 2) + (player.y + height / 2);

	if(cameraPosition[0] < 0)
		cameraPosition[0] = 0; 
	if(cameraPosition[1] < 0)
		cameraPosition[1] = 0;

}