Game controls

Learn how to play Pacman, understand the controls, and master the game mechanics. The game starts with a main menu screen showing the Pacman logo and ghost characters.

Key	Action
`SPACE`	Start the game
`ESC`	Exit to system

The menu features animated ghosts moving across the screen. Wait for them to complete their animation or press SPACE to begin immediately.

Once in the game, use arrow keys to navigate Pacman through the maze.

Movement keys

Arrow keys
System keys

Key	Direction	Code
`↑`	Move up	`SDLK_UP`
`↓`	Move down	`SDLK_DOWN`
`→`	Move right	`SDLK_RIGHT`
`←`	Move left	`SDLK_LEFT`

Key	Action
`ESC`	Exit game

Movement mechanics

The control system has several important characteristics:

Direction input

Press an arrow key to set Pacman’s desired direction:

if (keys[SDLK_UP]) {
  pc.yf = ((pc.y - 1) * 32);
  pc.dir = pc.x + pc.yf;
  if (c_array[(int)pc.dir] != 0.0 && c_array[(int)pc.dir] != P) {
    pc.inc_y = -1;
    pc.inc_x = 0;
  }
}

Movement validation

The game checks if the desired direction is valid (not a wall):

If valid: Pacman moves in that direction
If blocked: Input is buffered until the next valid position

Continuous movement

Pacman continues moving in the current direction until:

You press a different arrow key
A wall blocks the path
You reach a junction

Understanding the movement code

The game uses a grid-based movement system:

Grid size: 32x26 cells (MAXX_A x MAXY_A)
Cell spacing: 8 pixels (ESCALA)
Movement speed: Variable based on level (0.4 to 0.7)

Each direction sets increment values:

pc.inc_x = 1;   // Right
pc.inc_x = -1;  // Left
pc.inc_y = 1;   // Down
pc.inc_y = -1;  // Up

Position updates occur at:

pc.x += pc.inc_x;
pc.y += pc.inc_y;

Gameplay mechanics

Understanding the core game elements and how they interact.

Maze elements

The maze contains several types of elements:

Element	Symbol	Description
Walls	`0`	Impassable barriers
Paths	`C`	Paths with dots to collect
Empty	`N`	Empty spaces (ghost house)
Visited	`J`	Paths where dots were collected
Door	`P`	Ghost house door (closed)
Power pellets	`B`	Large dots that frighten ghosts

Collecting dots

The primary objective is collecting all dots in the maze.

Move over dots

Navigate Pacman over paths marked with dots:

if (c_array[(int)(pc.x + (pc.y * 32))] == C) {
  c_array[(int)(pc.x + (pc.y * 32))] = J;  // Mark as visited
  pc.puntos--;      // Decrease dot counter
  pc.puntuacion += 10;  // Add 10 points
}

Track progress

Total dots to collect: 226 (NUM_PUNTOS)Points per dot: 10Your score increases as you collect each dot.

Complete the level

When all dots are collected (pc.puntos == 0), you advance to the next level:

if (pc.puntos == 0) {
  adelanta_nivel(&fan, &pc);
}

Power pellets

Four large power pellets are positioned at the maze corners. Locations:

Top-left corner: (7, 1)
Top-right corner: (27, 1)
Bottom-left corner: (7, 24)
Bottom-right corner: (27, 24)

Effects when collected:

Scoring
Ghost behavior
Duration

Power pellet value: 50 points

pc.puntuacion += 50;

All normal ghosts become frightened:

pc.estado_pcman = ENFADADO;
for (int i = 0; i < 4; ++i) {
  if (fan.estado_fantasma[i] == NORMAL)
    fan.estado_fantasma[i] = ENFADADO;
}

Ghosts turn blue and flee from Pacman.

Level	Duration (ticks)	Seconds
0	273	~15s
1	198	~11s
2	162	~9s
3	126	~7s
4-12	90	~5s
13+	20	~1s

Power pellet duration decreases significantly at higher levels. Plan your ghost-hunting strategy accordingly.

Ghost mechanics

Four ghosts chase Pacman through the maze, each with distinct behavior.

Ghost types

The four ghosts have different AI patterns:

Blue (Azul)
Red (Rojo)
Yellow (Amarillo)
Gray (Gris)

Index: 0Strategy: Follows Pacman’s previous position

if (fan.estado_fantasma[0] == NORMAL) {
  fan.find_x[0] = pc.old_x;
  fan.find_y[0] = pc.old_y;
}

Behavior: Trails behind where Pacman was, attempting to cut off escape routes.

Index: 1Strategy: Direct pursuit of Pacman

if (fan.estado_fantasma[1] == NORMAL) {
  fan.find_x[1] = pc.x;
  fan.find_y[1] = pc.y;
}

Behavior: Most aggressive ghost. Always targets Pacman’s current position.

Index: 2Strategy: Conditional pursuit

if (fabs(pc.x - fan.x[2]) < 9 && fabs(pc.y - fan.y[2]) < 9) {
  fan.find_x[2] = pc.x;
  fan.find_y[2] = pc.y;
} else {
  fan.find_x[2] = rand() % MAXX_A;
  fan.find_y[2] = rand() % MAXY_A;
}

Behavior: Chases only when within 9 cells. Otherwise patrols randomly.

Index: 3Strategy: Wider detection range

if (fabs(pc.x - fan.x[3]) < 12 && fabs(pc.y - fan.y[3]) < 12) {
  fan.find_x[3] = pc.x;
  fan.find_y[3] = pc.y;
} else {
  fan.find_x[3] = rand() % MAXX_A;
  fan.find_y[3] = rand() % MAXY_A;
}

Behavior: Similar to yellow but with 12-cell detection radius.

Ghost states

Ghosts can be in three different states:

Normal state (0)

Appearance: Colored sprites (red, blue, yellow, gray)Behavior:

Chase Pacman according to AI pattern
Deadly on contact
Move at level-specific speed

Collision result:

if (fan.estado_fantasma[who] == NORMAL) {
  pc.num_vidas--;  // Lose a life
  if (pc.num_vidas < 0)
    menu_opciones(FALSE);  // Game over
  inicializa_structuras(pc, fan, FALSE);  // Reset positions
}

Frightened state (1)

Appearance: Blue ghosts (vulnerable)Triggered by: Collecting a power pelletBehavior:

Flee from Pacman
Move to random locations
Can be eaten

Duration: Varies by level (see power pellet duration table)

Dead state (2)

Appearance: Just eyesBehavior:

Return to ghost house
Cannot harm Pacman
Target position (16, 12) - ghost house center

Collision: No effect, ghost passes through

Eating ghosts

When you catch a frightened ghost, you earn points:

if (fan.estado_fantasma[who] == ENFADADO) {
  switch (control_puntos_fan_muerto) {
    case 0: pc.puntuacion += 50;  break;  // 1st ghost
    case 1: pc.puntuacion += 100; break;  // 2nd ghost
    case 2: pc.puntuacion += 150; break;  // 3rd ghost
    case 3: pc.puntuacion += 200; break;  // 4th ghost
  }
  fan.estado_fantasma[who] = MUERTO;
}

Ghost point values:

1st ghost: 50 points
2nd ghost: 100 points
3rd ghost: 150 points
4th ghost: 200 points

Eating all four ghosts during one power pellet gives you a total of 500 bonus points (50+100+150+200).

Special features

Advanced mechanics that affect gameplay.

Tunnels

The maze has vertical tunnels for quick travel:

if (pc.x == 16 && pc.y == 1) {
  pc.x = 16;
  pc.y = 24;  // Teleport to bottom
  pc.inc_y = -1;
} else if (pc.x == 16 && pc.y == 24) {
  pc.x = 16;
  pc.y = 1;   // Teleport to top
  pc.inc_y = 1;
}

Tunnel location: Center column (x=16) at top (y=1) and bottom (y=24) Usage: Move through the tunnel to quickly traverse the maze vertically.

Ghost house

Ghosts start in the central ghost house and are released in sequence: Release timing:

Blue ghost: Ticks 50-100 (leaves first)
Red ghost: Ticks 100-150
Yellow ghost: Ticks 150-200
Gray ghost: Ticks 200-240

Exit strategy:

if (fan.x[who] == 17 && fan.y[who] == 12 && 
    fan.estado_fantasma[who] == NORMAL) {
  if (CntStep2 >= 50 * (who + 1) && CntStep2 <= 50 * (who + 2)) {
    fan.inc_x[who] = 1;  // Move right to exit
    fan.inc_y[who] = 0;
  }
}

Collision detection

The game uses distance-based collision detection:

if (fabs((xf + j[who]) - (old_xp + jp + 1)) < 10 && 
    fabs((yf + i[who]) - (old_yp + ip)) < 10) {
  // Collision detected!
}

Collision radius: ~10 pixels in both X and Y directions

Scoring system

Understand how points are awarded.

Point values

Item	Points
Dot	10
Power pellet	50
1st ghost	50
2nd ghost	100
3rd ghost	150
4th ghost	200

Score calculation

Maximum points per level:

Dots: 226 × 10 = 2,260 points
Power pellets: 4 × 50 = 200 points
All ghosts (4 times): 4 × 500 = 2,000 points (if caught each time)

Theoretical maximum: ~4,460+ points per level

Score display: Your score is displayed at the top of the screen:

writef(40, 25, tablero->pixels, "%5d", pc.puntuacion);

Game progression

How the game difficulty increases.

Level system

Starting configuration:

pc.nivel = 0;           // Starting level
pc.num_vidas = 2;       // 2 lives (displayed as 3 total)
pc.puntuacion = 0;      // Starting score

Speed progression

Ghost speed increases with each level:

float velocidades[14] = {
4,    // Level 0
4231, // Level 1
4462, // Level 2
4692, // Level 3
4923, // Level 4
5154, // Level 5
5385, // Level 6
5615, // Level 7
5846, // Level 8
6077, // Level 9
6308, // Level 10
6538, // Level 11
6769, // Level 12
7     // Level 13+
};

Pacman speed: 0.5 (constant)

At level 13+, ghosts move faster than Pacman (0.7 vs 0.5), making the game extremely challenging.

Lives system

You start with 2 lives (3 total including current):

if (fan.estado_fantasma[who] == NORMAL) {
  pc.num_vidas--;
  if (pc.num_vidas < 0)
    menu_opciones(FALSE);  // Game over
}

Life loss: Getting caught by a normal ghost Game over: When num_vidas < 0 (all lives lost)

Strategy tips

Master the game with these proven strategies.

Dot collection strategy

Clear corners first

Start by clearing dots near power pellets, saving the pellets for when ghosts get close.

Plan your route

Try to clear the maze systematically rather than randomly wandering.

Use tunnels

The center tunnel (x=16) is excellent for escaping pursuing ghosts.

Ghost evasion

Know your enemies

Red ghost is most dangerous - always knows your position
Blue ghost follows where you were - change direction frequently
Yellow and gray ghosts only chase when close - keep distance

Cornering technique

When a ghost is approaching:

Wait at a junction
Let the ghost commit to a direction
Quickly turn perpendicular to escape

Power pellet timing

Optimal usage

Best times to grab a power pellet:

When multiple ghosts are nearby
When trapped with limited escape routes
When you can position yourself to catch multiple ghosts

Avoid wasting pellets when ghosts are far away.

Ghost hunting

After eating a power pellet:

Red ghost - Easiest to catch (always coming toward you)
Chase other ghosts quickly before effect wears off
Remember: 4 ghosts = 500 bonus points

Advanced techniques

Ghost house timing

Remember ghost release timing:

Early game: Fewer ghosts active
Wait for ghosts to exit before entering central area
Use this time to clear nearby dots safely

Speed advantage

Early levels (0-12): You’re faster or equal to ghosts

Use your speed to your advantage
Circle back on slower ghosts
Create distance when needed

Level 13+: Ghosts are faster

Rely more on strategy than speed
Use walls and turns to break line of sight
Power pellets become essential

Animation and visuals

Understanding the visual feedback.

Pacman animation

Pacman has 3 animation frames per direction:

if (CntStep3 == 0) 
  putico(old_xp + jp, old_yp, pc_der, vaddr, 14, 15);   // Open
else if (CntStep3 == 1) 
  putico(old_xp + jp, old_yp, pc_der2, vaddr, 11, 15);  // Half open
else 
  putico(old_xp + jp, old_yp, bola, vaddr, 15, 15);     // Closed (circle)

This creates the classic “chomping” animation.

Ghost animation

Ghosts alternate between 2 frames:

const int frame = (CntStep % 2 == 0) ? 0 : 1;

Each ghost has sprites for all 4 directions × 2 frames = 8 sprites each.

Visual states

Normal gameplay
Frightened mode
Death

Colored ghosts (red, blue, yellow, gray)
Pacman chomping in movement direction
Dots and power pellets visible

Next steps

Now that you understand the controls and mechanics:

Review the building guide to compile the game
Check the running guide for launch options
Explore src/teclado.c for input handling details
Study src/mov_fig.c for movement mechanics

Getting Started

Guides

Technical Details

Reference

Development

​Menu controls

​Main menu

​Game controls

​Movement keys

​Movement mechanics

​Gameplay mechanics

​Maze elements

​Collecting dots

​Power pellets

​Ghost mechanics

​Ghost types

​Ghost states

​Eating ghosts

​Special features

​Tunnels

​Ghost house

​Collision detection

​Scoring system

​Point values

​Score calculation

​Game progression

​Level system

​Speed progression

​Lives system

​Strategy tips

​Dot collection strategy

​Ghost evasion

​Power pellet timing

​Advanced techniques

​Animation and visuals

​Pacman animation

​Ghost animation

​Visual states

​Next steps

Build docs developers (and LLMs) love

Menu controls

Main menu

Game controls

Movement keys

Movement mechanics

Gameplay mechanics

Maze elements

Collecting dots

Power pellets

Ghost mechanics

Ghost types

Ghost states

Eating ghosts

Special features

Tunnels

Ghost house

Collision detection

Scoring system

Point values

Score calculation

Game progression

Level system

Speed progression

Lives system

Strategy tips

Dot collection strategy

Ghost evasion

Power pellet timing

Advanced techniques

Animation and visuals

Pacman animation

Ghost animation

Visual states

Next steps