Improve arduino_pong.ino using enum to handle game statuses and switch case for better readibility and little memory improvements

.github/workflows/cd.yml

@@ -0,0 +1,37 @@
+name: Arduino Pong CD
+
+on:
+  push:
+    tags:
+      - 'v*'
+
+permissions:
+  contents: write
+
+jobs:
+  release:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Install Arduino CLI
+        run: |
+          curl -fsSL https://raw.githubusercontent.com/arduino/arduino-cli/master/install.sh | sh
+          echo "./bin" >> $GITHUB_PATH
+
+      - name: Install Board Core and Libs
+        run: |
+          arduino-cli core update-index
+          arduino-cli core install arduino:renesas_uno
+
+      - name: Build Binary
+        run: make compile
+
+      - name: Create Release
+        uses: softprops/action-gh-release@v2
+        with:
+          files: |
+            build/*.bin
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

.github/workflows/ci.yml

@@ -3,17 +3,31 @@ name: Arduino Pong CI
 on:
   push:
     branches: [ master ]
+    paths:
+      - 'arduino_pong.ino'
+      - 'Makefile'
+      - '.github/workflows/ci.yml'
+      - 'src/*.cpp'
+      - 'src/*.h'
 
 jobs:
   build:
-    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        os: [ubuntu-latest, macos-latest, windows-latest]
+
+    runs-on: ${{ matrix.os }}
 
     steps:
       - name: Checkout Code
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Setup Arduino CLI
-        uses: arduino/setup-arduino-cli@v1
+        #uses: arduino/setup-arduino-cli@v2
+        shell: bash
+        run: |
+          curl -fsSL https://raw.githubusercontent.com/arduino/arduino-cli/master/install.sh | sh
+          echo "./bin" >> $GITHUB_PATH
 
       - name: Install UNO R4 Core
         run: |
@@ -21,4 +35,5 @@ jobs:
           arduino-cli core install arduino:renesas_uno
           
       - name: Compile Sketch (via Makefile)
-        run: make compile
+        shell: bash
+        run: make prepare_and_compile

.gitignore

@@ -0,0 +1,4 @@
+.secrets
+.arduino_cache/
+bin/
+build/

Makefile

@@ -1,16 +1,63 @@
+PORT ?= /dev/ttyACM0
+BOARD = arduino:renesas_uno:unor4wifi
+SKETCH = arduino_pong.ino
+CACHE_DIR = $(shell pwd)/.arduino_cache
+BIN_DIR = $(shell pwd)/bin
+CLI = $(BIN_DIR)/arduino-cli --config-file $(CACHE_DIR)/arduino-cli.yaml
+
+YELLOW := \033[0;33m
+GREEN  := \033[0;32m
+CLEAR  := \033[0m
+
+prepare:
+	@mkdir -p $(BIN_DIR)
+	@mkdir -p $(CACHE_DIR)
+	@if [ ! -f $(BIN_DIR)/arduino-cli ]; then \
+		echo -e "📥 $(YELLOW)Downloading arduino-cli...$(CLEAR)"; \
+		curl -fsSL https://raw.githubusercontent.com/arduino/arduino-cli/master/install.sh | BINDIR=$(BIN_DIR) sh; \
+	fi
+	@if [ ! -f $(CACHE_DIR)/arduino-cli.yaml ]; then \
+		echo -e "⚙️ $(YELLOW)Initializing local config...$(CLEAR)"; \
+		$(CLI) config init --dest-dir $(CACHE_DIR); \
+		$(CLI) config set directories.data $(CACHE_DIR)/data; \
+		$(CLI) config set directories.downloads $(CACHE_DIR)/downloads; \
+		$(CLI) config set directories.user $(CACHE_DIR)/user; \
+	fi
+	@if ! $(CLI) core list | grep -q "arduino:renesas_uno"; then \
+		echo -e "$(YELLOW)📥 Installing board core...$(CLEAR)"; \
+		$(CLI) core update-index; \
+		$(CLI) core install arduino:renesas_uno; \
+	fi
+
 compile:
-	arduino-cli compile -b arduino:renesas_uno:unor4wifi ./arduino_pong.ino
+	@mkdir -p build
+	@echo -e "$(GREEN)🛠️  Compiling $(SKETCH)...$(CLEAR)"
+	@$(CLI) compile -b $(BOARD) --output-dir build $(SKETCH)
+
+clean:
+	@echo -e "$(GREEN)🛠️  Removing build files...$(CLEAR)"
+	@rm -rf build/
+
+prepare_and_compile:
+	make prepare --no-print-directory
+	make compile --no-print-directory
 
 upload:
-	arduino-cli upload -b arduino:renesas_uno:unor4wifi -p /dev/ttyACM0
+	@echo -e "$(GREEN)🚀  Uploading $(SKETCH)...$(CLEAR)"
+	@$(CLI) upload -b $(BOARD) -p $(PORT)
 
 upload_verbose:
-	arduino-cli upload -b arduino:renesas_uno:unor4wifi -p /dev/ttyACM0 -v
+	@echo -e "$(GREEN)🚀  Uploading (Verbose) $(SKETCH)...$(CLEAR)"
+	@$(CLI) upload -b $(BOARD) -p $(PORT) -v
 
 monitor:
-	arduino-cli monitor -p /dev/ttyACM0
+	@$(CLI) monitor -p $(PORT)
 
 run:
-	make compile
+	make compile --no-print-directory
-	make upload
+	make upload --no-print-directory
-	make monitor
+	make monitor --no-print-directory
+
+run_init:
+	make prepare --no-print-directory
+	make run --no-print-directory

README.md

@@ -2,9 +2,13 @@
 
 A classic implementation of the Pong game developed specifically for the Arduino UNO R4 WiFi, utilizing its built-in 12×8 LED matrix as the game screen.
 
+[![Arduino Pong CI](https://github.com/Dea1993/arduino_pong/actions/workflows/ci.yml/badge.svg?branch=master)](https://github.com/Dea1993/arduino_pong/actions/workflows/ci.yml)
+[![Arduino Pong CD](https://github.com/Dea1993/arduino_pong/actions/workflows/cd.yml/badge.svg)](https://github.com/Dea1993/arduino_pong/actions/workflows/cd.yml)
+[![License: GPL v3](https://img.shields.io/badge/License-GPLv3-blue.svg)](LICENSE)
+
 # 📹 Preview
 
-![Pong](preview.png)
+![Pong](assets/preview.png)
 
 Youtube: https://youtu.be/ouLBTDjpKqc
 
@@ -54,9 +58,11 @@ This project includes a `Makefile` to automate the workflow using `arduino-cli`.
 ### Commands
 | Command | Description |
 | :--- | :--- |
+| `make prepare` | Downloads arduino-cli locally and installs the UNO R4 core. |
 | `make compile` | Compiles the sketch without uploading. |
 | `make upload` | Uploads the compiled binary to `/dev/ttyACM0`. |
 | `make monitor` | Opens the Serial Monitor. |
 | `make run` | Full cycle: Compile + Upload + Monitor. |
+| `make run_init` | Full first-time setup: Prepare env + Compile + Upload + Monitor. |
 
 > **Note:** If your board is on a different port, edit the `Makefile` or override it: `make upload PORT=/dev/ttyUSB0`.

arduino_pong.ino

@@ -1,207 +1,122 @@
 #include "Arduino_LED_Matrix.h"
 
-#define P1_BTN_UP 13
+#include "src/config.h"
-#define P1_BTN_BOTTOM 12
+#include "src/pong_render.h"
-#define P2_BTN_UP 11
+#include "src/pong_player.h"
-#define P2_BTN_BOTTOM 10
+#include "src/pong_ball.h"
 
 // create LED matrix object
 ArduinoLEDMatrix matrix;
 
-// initial pong frame
+// initial pong frame matrix
-byte frame[8][12] = {
+byte frame[MATRIX_HEIGHT][MATRIX_WIDTH] = {
   { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
   { 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
   { 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
-  { 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0 },
+  { 1, 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, 1, 0, 0, 0, 0, 1 },
   { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 },
   { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 },
   { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }
 };
 
 // players coordinates
-int p1_start= 1;
+int players_coords[2]= {1, 4};
-int p1_end= 3;
+int players_scores[2]= {0, 0};
-
-int p2_start= 4;
-int p2_end= 6;
 
 // initials balls coordinates
-int ball_reset_x=6;
+int ball_x= BALL_RESET_X;
-int ball_reset_y=3;
+int ball_y= BALL_RESET_Y;
-int ball_x= ball_reset_x;
-int ball_y= ball_reset_y;
 
-// initially ball has no movements
+int need_refresh= true;
-// once game/round starts, balls gets random x and y movements
-int ball_move_x= 0;
-int ball_move_y= 0;
 
-int bar_length= 3;
+int ball_delay= INITIAL_BALL_DELAY;
-int p1_score= 0;
-int p2_score= 0;
-
-int need_refresh= 1;
-
-int initial_loop_delay= 200;
-int loop_delay= initial_loop_delay;
-// used to increase speed when game is too easy
-int hits= 0;
 
 long exec_t2= millis();
 
+enum game_statuses : uint8_t {
+  TIMER,
+  RUN,
+  SCORE,
+  GAMEOVER,
+  WAIT,
+};
+game_statuses game_status= TIMER;
+
+
 void setup() {
-  //Serial.begin(115200);
   Serial.begin(9600);
-  // stard LED matrix
+  // start LED matrix
   matrix.begin();
+
   pinMode(P1_BTN_UP, INPUT_PULLUP);
   pinMode(P1_BTN_BOTTOM, INPUT_PULLUP);
   pinMode(P2_BTN_UP, INPUT_PULLUP);
   pinMode(P2_BTN_BOTTOM, INPUT_PULLUP);
 
-  randomSeed(analogRead(0));
+  randomSeed(millis());
-}
-
-void render_matrix() {
-  if (!need_refresh) return;
-  need_refresh= 0;
-  // clear
-  for (int x=0; x < 12; x++) {
-    for (int y=0; y < 8; y++) {
-      frame[y][x]= 0;
-      frame[y][x]= 0;
-    }
-  }
-  
-  // players coords
-  for (int i= p1_start; i < p1_start+bar_length; i++) {
-    frame[i][0]= 1;
-  }
-  for (int i= p2_start; i < p2_start+bar_length; i++) {
-    frame[i][11]= 1;
-  }
-  
-  // ball coords
-  frame[ball_y][ball_x]= 1;
-
-  matrix.renderBitmap(frame, 8, 12);
-}
-
-void pong_move_p1() {
-  if (digitalRead(P1_BTN_UP) == LOW && p1_start > 0) {
-    p1_start -= 1;
-    need_refresh= 1;
-  }
-  else if (digitalRead(P1_BTN_BOTTOM) == LOW && p1_start < 5) {
-    p1_start += 1;
-    need_refresh= 1;
-  }
-}
-
-void pong_move_p2() {
-  if (digitalRead(P2_BTN_UP) == LOW && p2_start > 0) {
-    p2_start -= 1;
-    need_refresh= 1;
-  }
-  else if (digitalRead(P2_BTN_BOTTOM) == LOW && p2_start < 5) {
-    p2_start += 1;
-    need_refresh= 1;
-  }
-}
-
-int ball_player_collision(int player) {
-  for (int p= player; p < player + bar_length; p++) {
-    if (ball_y == p) {
-      return 1;
-    }
-  }
-  return 0;
-}
-
-void point_scored() {
-  ball_x= ball_reset_x;
-  ball_y= ball_reset_y;
-  Serial.print("P1: ");
-  Serial.print(p1_score);
-  Serial.print(" - ");
-  Serial.print("P2: ");
-  Serial.print(p2_score);
-  Serial.println();
-
-  hits= 0;
-  loop_delay= initial_loop_delay;
-}
-
-void move_ball() {
-  need_refresh= 1;
-  if (ball_x < 0 || ball_x > 11 || ball_y < 0 || ball_y > 7) {
-    // ball out of matrix limits
-    ball_x= ball_reset_x;
-    ball_y= ball_reset_y;
-    return;
-  }
-  
-  // if ball is not moving, get random direction
-  // this is the initial position
-  if (ball_move_x == 0 || ball_move_y == 0) {
-    // extract random number between 0 or 1 to select the directions
-    if (random(2) == 0) ball_move_x= 1;
-    else ball_move_x= -1;
-    if (random(2) == 0) ball_move_y= 1;
-    else ball_move_y= -1;
-  }
-
-  else if (ball_x == 0) {
-    // if p1 collision: reverse x, go left
-    if (!ball_player_collision(p1_start)) {
-      // else p2 score, reset board
-      p2_score += 1;
-      Serial.println("Player 2 Point");
-      point_scored();
-    }
-    else {
-      hits += 1;
-      ball_move_x= ball_move_x * -1;
-    }
-  }
-  else if (ball_x == 11) {
-    if (!ball_player_collision(p2_start)) {
-      // else p1 score, reset board
-      p1_score += 1;
-      Serial.println("Player 1 Point");
-      point_scored();
-    }
-    else {
-      hits += 1;
-      ball_move_x= ball_move_x * -1;
-    }
-  }
-
-  if (ball_y == 0 || ball_y == 7) {
-    // reverse y, go down
-    ball_move_y= ball_move_y * -1;
-  }
-
-  if (hits >= 6 && loop_delay >= 80) {
-    // increase ball speed
-    hits = 0;
-    loop_delay -= 20;
-  }
-
-  ball_x+= ball_move_x;
-  ball_y+= ball_move_y;
 }
 
 void loop() {
   long exec_t1= millis();
-  pong_move_p1();
+
-  pong_move_p2();
+  switch (game_status) {
-  render_matrix();
+    case TIMER:
-  if (exec_t1 - exec_t2 > loop_delay) {
+      for (int i = START_TIMER; i >= 0; i--) {
-    move_ball();
+        render_timer(frame, i);
-    exec_t2= exec_t1;
+        delay(1000);
+        matrix.renderBitmap(frame, MATRIX_HEIGHT, MATRIX_WIDTH);
+      }
+      game_status= RUN;
+      // delay the first ball movement
+      exec_t2= millis() + FIRST_START_BALL_DELAY;
+      break;
+
+    case RUN:
+      pong_move_p1(players_coords[0], need_refresh);
+      pong_move_p2(players_coords[1], need_refresh);
+      if (exec_t1 - exec_t2 > ball_delay) {
+        need_refresh= true;
+        bool scored= move_ball(ball_x, ball_y, ball_delay, players_coords, players_scores);
+        if (scored) {
+          game_status= SCORE;
+          // delay the ball movement after score
+          exec_t2= millis() + FIRST_START_BALL_DELAY;
+        } else exec_t2= exec_t1;
+      }
+      // rerender matrix only if something is changed
+      if (need_refresh) {
+        render_matrix(frame, players_coords, ball_x, ball_y);
+        matrix.renderBitmap(frame, MATRIX_HEIGHT, MATRIX_WIDTH);
+        need_refresh= 0;
       }
       delay(50);
+      break;
+
+    case SCORE:
+      render_score(frame, players_scores);
+      matrix.renderBitmap(frame, MATRIX_HEIGHT, MATRIX_WIDTH);
+      delay(1000);
+      if (players_scores[0] >= MAX_POINTS || players_scores[1] >= MAX_POINTS) {
+        game_status= GAMEOVER;
+      }
+      else game_status= RUN;
+      break;
+
+    case GAMEOVER:
+      render_winner(frame, matrix, players_scores);
+      game_status= WAIT;
+      break;
+
+    case WAIT:
+      // keep showing the winner waiting for a restart
+      // restart game once one button is pressed
+      if (digitalRead(P1_BTN_UP) == LOW || digitalRead(P1_BTN_BOTTOM) == LOW || digitalRead(P2_BTN_UP) == LOW || digitalRead(P2_BTN_BOTTOM) == LOW) {
+        game_status= TIMER;
+        players_scores[0]= 0;
+        players_scores[1]= 0;
+      }
+      delay(100);
+      break;
+  }
 }

src/config.h

@@ -0,0 +1,15 @@
+#define P1_BTN_UP 12
+#define P1_BTN_BOTTOM 11
+#define P2_BTN_UP 10
+#define P2_BTN_BOTTOM 9
+
+#define MATRIX_WIDTH 12
+#define MATRIX_HEIGHT 8
+#define BALL_RESET_X (MATRIX_WIDTH / 2)
+#define BALL_RESET_Y (MATRIX_HEIGHT / 2)
+#define BAR_LENGTH 3
+#define INITIAL_BALL_DELAY 200
+
+#define MAX_POINTS 9
+#define START_TIMER 3
+#define FIRST_START_BALL_DELAY 500

src/font.h

@@ -0,0 +1,184 @@
+#ifndef FONT_H
+#define FONT_H
+
+#include <Arduino.h>
+
+const uint32_t pone_wins[][4] = {
+	{
+		0x78,
+		0xc4847844,
+		0x440e000,
+		500
+	},
+	{
+		0x11,
+		0x1101501,
+		0x501f0000,
+		500
+	},
+	{
+		0xe,
+		0x400400,
+		0x400e0000,
+		500
+	},
+	{
+		0x9,
+		0xd00b00,
+		0x90090000,
+		500
+	},
+	{
+		0xf,
+		0x800f00,
+		0x100f0000,
+		500
+	}
+};
+const uint32_t ptwo_wins[][4] = {
+	{
+		0x79,
+		0xe48279e4,
+		0x1041e000,
+		500
+	},
+	{
+		0x11,
+		0x1101501,
+		0x501f0000,
+		500
+	},
+	{
+		0xe,
+		0x400400,
+		0x400e0000,
+		500
+	},
+	{
+		0x9,
+		0xd00b00,
+		0x90090000,
+		500
+	},
+	{
+		0xf,
+		0x800f00,
+		0x100f0000,
+		500
+	}
+};
+
+const byte font_pong[10][8][3] = {
+  // Number 0
+  {
+    { 0, 0, 0 },
+    { 0, 0, 0 },
+    { 1, 1, 1 },
+    { 1, 0, 1 },
+    { 1, 0, 1 },
+    { 1, 0, 1 },
+    { 1, 1, 1 },
+    { 0, 0, 0 }
+  },
+  // Number 1
+  {
+    { 0, 0, 0 },
+    { 0, 0, 0 },
+    { 1, 1, 0 },
+    { 0, 1, 0 },
+    { 0, 1, 0 },
+    { 0, 1, 0 },
+    { 1, 1, 1 },
+    { 0, 0, 0 }
+  },
+  // Number 2
+  {
+    { 0, 0, 0 },
+    { 0, 0, 0 },
+    { 1, 1, 1 },
+    { 0, 0, 1 },
+    { 1, 1, 1 },
+    { 1, 0, 0 },
+    { 1, 1, 1 },
+    { 0, 0, 0 }
+  },
+  // Number 3
+  {
+    { 0, 0, 0 },
+    { 0, 0, 0 },
+    { 1, 1, 1 },
+    { 0, 0, 1 },
+    { 1, 1, 1 },
+    { 0, 0, 1 },
+    { 1, 1, 1 },
+    { 0, 0, 0 }
+  },
+  // Number 4
+  {
+    { 0, 0, 0 },
+    { 0, 0, 0 },
+    { 1, 0, 1 },
+    { 1, 0, 1 },
+    { 1, 1, 1 },
+    { 0, 0, 1 },
+    { 0, 0, 1 },
+    { 0, 0, 0 }
+  },
+  // Number 5
+  {
+    { 0, 0, 0 },
+    { 0, 0, 0 },
+    { 1, 1, 1 },
+    { 1, 0, 0 },
+    { 1, 1, 1 },
+    { 0, 0, 1 },
+    { 1, 1, 1 },
+    { 0, 0, 0 }
+  },
+  // Number 6
+  {
+    { 0, 0, 0 },
+    { 0, 0, 0 },
+    { 1, 0, 0 },
+    { 1, 0, 0 },
+    { 1, 1, 1 },
+    { 1, 0, 1 },
+    { 1, 1, 1 },
+    { 0, 0, 0 }
+  },
+  // Number 7
+  {
+    { 0, 0, 0 },
+    { 0, 0, 0 },
+    { 1, 1, 1 },
+    { 0, 0, 1 },
+    { 0, 0, 1 },
+    { 0, 0, 1 },
+    { 0, 0, 1 },
+    { 0, 0, 0 }
+  },
+  // Number 8
+  {
+    { 0, 0, 0 },
+    { 0, 0, 0 },
+    { 1, 1, 1 },
+    { 1, 0, 1 },
+    { 1, 1, 1 },
+    { 1, 0, 1 },
+    { 1, 1, 1 },
+    { 0, 0, 0 }
+  },
+  // Number 9
+  {
+    { 0, 0, 0 },
+    { 0, 0, 0 },
+    { 1, 1, 1 },
+    { 1, 0, 1 },
+    { 1, 1, 1 },
+    { 0, 0, 1 },
+    { 0, 0, 1 },
+    { 0, 0, 0 }
+  },
+};
+
+#endif

src/pong_ball.cpp

@@ -0,0 +1,97 @@
+#include <Arduino.h>
+#include "config.h"
+#include "pong_player.h"
+
+// used to increase speed when game is too easy
+int hits= 0;
+
+// initially ball has no movements
+// once game/round starts, balls gets random x and y movements
+int ball_move_x= 0;
+int ball_move_y= 0;
+
+void random_ball_movement(int &ball_move_x, int &ball_move_y) {
+  if (random(2) == 0) ball_move_x= 1;
+  else ball_move_x= -1;
+  if (random(2) == 0) ball_move_y= 1;
+  else ball_move_y= -1;
+}
+
+void point_scored(int &ball_x, int &ball_y, int &ball_delay, int players_scores[2], int &ball_move_x, int &ball_move_y) {
+  ball_x= BALL_RESET_X;
+  ball_y= BALL_RESET_Y;
+  random_ball_movement(ball_move_x, ball_move_y);
+
+  Serial.print("P1: ");
+  Serial.print(players_scores[0]);
+  Serial.print(" - ");
+  Serial.print("P2: ");
+  Serial.print(players_scores[1]);
+  Serial.println();
+
+  hits= 0;
+  ball_delay= INITIAL_BALL_DELAY;
+}
+
+bool move_ball(int &ball_x, int &ball_y, int &ball_delay, int players_coords[2], int players_scores[2]) {
+  if (ball_x < 0 || ball_x > MATRIX_WIDTH-1 || ball_y < 0 || ball_y > MATRIX_HEIGHT-1) {
+    // ball out of matrix limits
+    ball_x= BALL_RESET_X;
+    ball_y= BALL_RESET_Y;
+    return false;
+  }
+
+  bool scored= false;
+  
+  // if ball is not moving, get random direction
+  // this is the initial position
+  if (ball_move_x == 0 || ball_move_y == 0) {
+    // extract random number between 0 or 1 to select the directions
+    random_ball_movement(ball_move_x, ball_move_y);
+  }
+
+  else if (ball_x == 0) {
+    // if p1 collision: reverse x, go left
+    if (!ball_player_collision(players_coords[0], ball_y)) {
+      // else p2 score, reset board
+      players_scores[1] += 1;
+      scored= true;
+      Serial.println("Player 2 Scores");
+      point_scored(ball_x, ball_y, ball_delay, players_scores, ball_move_x, ball_move_y);
+      return true;
+    }
+    else {
+      hits += 1;
+      ball_move_x= ball_move_x * -1;
+    }
+  }
+  else if (ball_x == MATRIX_WIDTH-1) {
+    if (!ball_player_collision(players_coords[1], ball_y)) {
+      // else p1 score, reset board
+      players_scores[0] += 1;
+      scored= true;
+      Serial.println("Player 1 Scores");
+      point_scored(ball_x, ball_y, ball_delay, players_scores, ball_move_x, ball_move_y);
+      return true;
+    }
+    else {
+      hits += 1;
+      ball_move_x= ball_move_x * -1;
+    }
+  }
+
+  if (ball_y == 0 || ball_y == MATRIX_HEIGHT-1) {
+    // reverse y, go down
+    ball_move_y= ball_move_y * -1;
+  }
+
+  if (hits >= 6 && ball_delay >= 80) {
+    // increase ball speed
+    hits= 0;
+    ball_delay-= 20;
+  }
+
+  ball_x+= ball_move_x;
+  ball_y+= ball_move_y;
+  return scored;
+}

src/pong_ball.h

@@ -0,0 +1,6 @@
+#ifndef PONG_BALL_H
+#define PONG_BALL_H
+
+bool move_ball(int &ball_x, int &ball_y, int &loop_delay, int players_coords[2], int players_scores[2]);
+void foo(); 
+#endif

src/pong_player.cpp

@@ -0,0 +1,33 @@
+#include <Arduino.h>
+#include "config.h"
+
+int ball_player_collision(int player, int ball_y) {
+  for (int p= player; p < player + BAR_LENGTH; p++) {
+    if (ball_y == p) {
+      return 1;
+    }
+  }
+  return 0;
+}
+
+int pong_move_p1(int &p1_start, int &need_refresh) {
+  if (digitalRead(P1_BTN_UP) == LOW && p1_start > 0) {
+    p1_start -= 1;
+    need_refresh= true;
+  }
+  else if (digitalRead(P1_BTN_BOTTOM) == LOW && p1_start < 5) {
+    p1_start += 1;
+    need_refresh= true;
+  }
+}
+
+int pong_move_p2(int &p2_start, int &need_refresh) {
+  if (digitalRead(P2_BTN_UP) == LOW && p2_start > 0) {
+    p2_start -= 1;
+    need_refresh= true;
+  }
+  else if (digitalRead(P2_BTN_BOTTOM) == LOW && p2_start < 5) {
+    p2_start += 1;
+    need_refresh= true;
+  }
+}

src/pong_player.h

@@ -0,0 +1,8 @@
+#ifndef PONG_PLAYER_H
+#define PONG_PLAYER_H
+
+int ball_player_collision(int player, int ball_y);
+int pong_move_p1(int &p1_start, int &need_refresh);
+int pong_move_p2(int &p2_start, int &need_refresh);
+
+#endif

src/pong_render.cpp

@@ -0,0 +1,75 @@
+#include <Arduino.h>
+#include "Arduino_LED_Matrix.h"
+#include "config.h"
+#include "font.h"
+
+void clear_matrix(byte frame[MATRIX_HEIGHT][MATRIX_WIDTH]) {
+  for (int x=0; x < MATRIX_WIDTH; x++) {
+    for (int y=0; y < MATRIX_HEIGHT; y++) {
+      frame[y][x]= 0;
+    }
+  }
+}
+
+void render_matrix(byte frame[MATRIX_HEIGHT][MATRIX_WIDTH], int players_coords[2], int ball_x, int ball_y) {
+  clear_matrix(frame);
+  int player_one= players_coords[0];
+  int player_two= players_coords[1];
+  // players coords
+  for (int i= player_one; i < player_one+BAR_LENGTH; i++) {
+    frame[i][0]= 1;
+  }
+  for (int i= player_two; i < player_two+BAR_LENGTH; i++) {
+    frame[i][MATRIX_WIDTH-1]= 1;
+  }
+  
+  // ball coords
+  frame[ball_y][ball_x]= 1;
+}
+
+void render_score(byte frame[MATRIX_HEIGHT][MATRIX_WIDTH], int players_scores[2]) {
+  clear_matrix(frame);
+  int player_one= players_scores[0];
+  int player_two= players_scores[1];
+  if (player_one > 9) player_one = 9;
+  if (player_two > 9) player_two = 9;
+  
+  // player score separator (-)
+  frame[4][5]= 1;
+  frame[4][6]= 1;
+
+  for (int h=0; h < 8; h++) {
+    for (int w=0; w < 3; w++) {
+      frame[h][w+1]= font_pong[player_one][h][w];
+    }
+  }
+  for (int h=0; h < 8; h++) {
+    for (int w=0; w < 3; w++) {
+      frame[h][w+8]= font_pong[player_two][h][w];
+    }
+  }
+}
+
+void render_timer(byte frame[MATRIX_HEIGHT][MATRIX_WIDTH], int seconds) {
+  clear_matrix(frame);
+
+  for (int h=0; h < 8; h++) {
+    for (int w=0; w < 3; w++) {
+      frame[h][w+5]= font_pong[seconds][h][w];
+    }
+  }
+}
+
+void render_winner(byte frame[MATRIX_HEIGHT][MATRIX_WIDTH], ArduinoLEDMatrix &matrix, int players_scores[2]) {
+  clear_matrix(frame);
+  // check winner 
+  if (players_scores[0] > players_scores[1]) {
+    Serial.println("Player 1 wins!!!");
+    matrix.loadSequence(pone_wins);
+  }
+  else {
+    Serial.println("Player 2 wins!!!");
+    matrix.loadSequence(ptwo_wins);
+  }
+  matrix.play(true);
+}

src/pong_render.h

@@ -0,0 +1,13 @@
+#ifndef PONG_RENDER_H
+#define PONG_RENDER_H
+
+#include <Arduino.h>
+#include "Arduino_LED_Matrix.h"
+#include "config.h"
+
+void render_matrix(byte frame[MATRIX_HEIGHT][MATRIX_WIDTH], int players_coords[2], int ball_x, int ball_y);
+void render_score(byte frame[MATRIX_HEIGHT][MATRIX_WIDTH], int players_scores[2]);
+void render_timer(byte frame[MATRIX_HEIGHT][MATRIX_WIDTH], int seconds);
+void render_winner(byte frame[MATRIX_HEIGHT][MATRIX_WIDTH], ArduinoLEDMatrix &matrix, int players_scores[2]);
+
+#endif