Working on fixing the 'ball position' bug (turns out it isn't actually fixed)

Makefile

@@ -1,2 +1,4 @@
-build:
-	gcc pong.c -o pong -lallegro_color -lallegro_ttf -lallegro_font -lallegro_image -lallegro_primitives -lallegro
+LDLIBS = -lm -lallegro_color -lallegro_ttf -lallegro_font -lallegro_image -lallegro_primitives -lallegro
+CFLAGS += -g -Wall -Wextra
+
+pong:

pong.c

@@ -1,9 +1,11 @@
 #include <stdio.h>
+#include <stdlib.h>
 #include <allegro5/allegro.h>
 #include <allegro5/allegro_font.h>
 #include <allegro5/allegro_ttf.h>
 #include <allegro5/allegro_image.h>
 #include <allegro5/allegro_primitives.h>
+#include <math.h>
 
 #define WIN_WIDTH 1000
 #define WIN_HEIGHT 600
@@ -21,7 +23,6 @@ void alleg_init() {
 	return;
 }
 
-
 int main(int argc, char** argv) {
 //	Initialization
 
@@ -31,8 +32,11 @@ int main(int argc, char** argv) {
 	al_register_event_source(queue,al_get_keyboard_event_source());
 	ALLEGRO_COLOR black = al_map_rgba(0,0,0,255);
 	ALLEGRO_COLOR white = al_map_rgba(255,255,255,255);
-	ALLEGRO_EVENT event;
-	bool running = true;
+	ALLEGRO_EVENT temp_event;
+	ALLEGRO_FONT* main_font = al_load_ttf_font("/usr/share/fonts/cantarell/Cantarell-VF.otf", 30, 0);
+
+	bool running = false;
+	srand(time(NULL)); // Seed for RNG
 
 	float width = 25;  // Width and height of paddles
 	float height = 150;
@@ -43,11 +47,32 @@ int main(int argc, char** argv) {
 	float velocity_1 = 0;  // Vertical velocity of first paddle
 	float velocity_2 = 0;  // Vertical velocity of second paddle
 
-	float circ_x = WIN_WIDTH / 2; // Center coordinates of ball
-	float circ_y = WIN_HEIGHT / 2;
-	float circ_rad = 10;  // Radius of ball
-	float circ_vel_x = 5; // Horizontal velocity of ball
-	float circ_vel_y = 0; // Vertical velocity of ball
+	float circ_x = 60; // Center coordinates of ball
+	float circ_y = 25;
+	float circ_rad = 15;  // Radius of ball
+	float ball_speed = sqrt(72); // Pythagorean distance travelled by ball in one main-loop iteration
+	float circ_vel_x = (float)(rand())/(float)(RAND_MAX / 3) + 4.0; // Horizontal velocity of ball (Randomly generated, 4 to 7) - borrowed from https://stackoverflow.com/a/13409133
+	float circ_vel_y = sqrt(pow(ball_speed,2) - pow(circ_vel_x,2)); // Vertical velocity of ball - Subtract X velocity from hypotenuse / ball_speed
+
+	int score_1 = 0; // Player 1 score
+	int score_2 = 0; // Player 2 score
+
+//	I reset the ball position here, so that the ball starts from the same place after I press SPACE
+	circ_x = 60;
+	circ_y = 25;
+
+	al_clear_to_color(black);
+	al_draw_filled_rectangle(start_x_1, start_y_1, start_x_1 + width, start_y_1 + height, white);
+	al_draw_filled_rectangle(start_x_2, start_y_2, start_x_2 + width, start_y_2 + height, white);
+	al_draw_filled_circle(circ_x, circ_y, circ_rad, white);
+	al_draw_text(main_font, white, (WIN_WIDTH / 2), (WIN_HEIGHT / 2), ALLEGRO_ALIGN_CENTRE, "Welcome to Pong!\0");
+	al_flip_display();
+
+	do {
+		al_wait_for_event(queue, &temp_event);
+	} while (!(temp_event.type == ALLEGRO_EVENT_KEY_DOWN && temp_event.keyboard.keycode == ALLEGRO_KEY_SPACE));
+
+	running = true;
 
 	al_clear_to_color(black);
 	al_draw_filled_rectangle(start_x_1, start_y_1, start_x_1 + width, start_y_1 + height, white);
@@ -56,10 +81,11 @@ int main(int argc, char** argv) {
 	al_flip_display();
 
 	while (running) {
+		ALLEGRO_EVENT event;
 		// Code borrowed from: https://stackoverflow.com/a/30078011
 
 		while (!al_is_event_queue_empty(queue)) {
-			al_wait_for_event(queue, &event);
+			al_get_next_event(queue, &event);
 
 			if (event.type == ALLEGRO_EVENT_KEY_DOWN) {
 				switch (event.keyboard.keycode) {
@@ -68,7 +94,7 @@ int main(int argc, char** argv) {
 						break;
 					case ALLEGRO_KEY_S:
 						velocity_1 += 5;
-						break; 
+						break;
 					case ALLEGRO_KEY_UP:
 						velocity_2 -= 5;
 						break;
@@ -107,12 +133,6 @@ int main(int argc, char** argv) {
 		((velocity_2 < 0 && start_y_2  > 0) || (velocity_2 > 0 && start_y_2 + height < WIN_HEIGHT)) && (start_y_2 += velocity_2);
 		circ_x += circ_vel_x;
 		circ_y += circ_vel_y;
-		
-		//Redraw shapes
-		al_draw_filled_rectangle(start_x_1, start_y_1, start_x_1 + width, start_y_1 + height + velocity_1, white);		
-		al_draw_filled_rectangle(start_x_2, start_y_2, start_x_2 + width, start_y_2 + height + velocity_2, white);		
-		al_draw_filled_circle(circ_x, circ_y, circ_rad, white);
-		al_flip_display();
 
 		if (circ_x + circ_rad >= WIN_WIDTH - 10 - width) { // FOR PADDLE 2: If the circle has reached the point where the paddle would be...
 			if (circ_y > start_y_2 && circ_y < start_y_2 + height) { // If the circle is touching the paddle...
@@ -120,15 +140,42 @@ int main(int argc, char** argv) {
 			}
 		} else if (circ_x - circ_rad <= 10 + width) { // FOR PADDLE 1
 			if (circ_y > start_y_1 && circ_y < start_y_1 + height) {
-				circ_vel_x =- circ_vel_x;
+				circ_vel_x = -circ_vel_x;
 			}
 		}
 
+		if ((circ_y + circ_rad >= WIN_HEIGHT) || (circ_y - circ_rad <= 0)) {
+			circ_vel_y = -circ_vel_y;
+		}
+
+		if (circ_x - circ_rad <= 0 || circ_x + circ_rad >= WIN_WIDTH) {
+			if (circ_x - circ_rad <= 0) {
+				score_2++;
+			}
+			if (circ_x + circ_rad >= WIN_WIDTH) {
+				score_1++;
+			}
+			printf("Player 1: %d\n",score_1);
+			printf("Player 2: %d\n\n", score_2);
+			circ_x = 60;
+			circ_y = 25;
+			circ_vel_x = (float)(rand())/(float)(RAND_MAX / 3) + 4.0;
+			circ_vel_y = sqrt(pow(ball_speed,2) - pow(circ_vel_x,2));
+			sleep(1);
+		}
+
+		//Redraw shapes
+		al_draw_filled_rectangle(start_x_1, start_y_1, start_x_1 + width, start_y_1 + height + velocity_1, white);
+		al_draw_filled_rectangle(start_x_2, start_y_2, start_x_2 + width, start_y_2 + height + velocity_2, white);
+		al_draw_filled_circle(circ_x, circ_y, circ_rad, white);
+		al_flip_display();
+
+	printf("Ball x: %.0f y: %.0f\n", circ_x, circ_y);
 	}
 
 //	Clean up
 	al_destroy_display(disp);
-	al_destroy_event_queue(queue);	
-	
+	al_destroy_event_queue(queue);
+
 	return 0;
 }