Scripting: Keyboard and Mouse I/O

Now that you've mastered the basics, it's time to learn how to handle user input! This allows your scripts to respond to keyboard presses and mouse clicks, making your games truly interactive.

We'll cover both events (which trigger automatically) and functions (which you can check manually).

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Keyboard Input

Keyboard Events

These events trigger automatically when keys are pressed:

onKeyPressed(keycode, key, scancode)

Triggers every time a key is pressed:

//#CLIENTSIDE
function onKeyPressed(keycode, key, scancode) {
    player.chat = "I just pressed " @ key @ " guys!!";
}

onWeaponFired()

Triggers when the weapon key is pressed (make sure you have a weapon equipped!):

//#CLIENTSIDE
// Fireball Weapon Example
function onWeaponFired() {
    setani("grab", "");
    shootfireball(player.dir);
    freezeplayer(0.1);
    sleep(0.1);
    setani("idle", "");
}

Keyboard Functions

keydown(keyvalue)

Check if a specific key is currently being held down:

//#CLIENTSIDE
function onKeyPressed() {
    if (keydown(5)) { // S key (Attack/Sword)
        player.chat = "Shishishaww!";
    }
}

Key Values Reference

Key Value	Key Name	Description
0	Up	Up arrow key
1	Left	Left arrow key
2	Down	Down arrow key
3	Right	Right arrow key
4	D	Weapon key
5	S	Attack/Sword key
6	A	Grab key
7	M	Map key
8	TAB	Chat bar toggle
9	Q	Inventory key
10	Pause	Pause key

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Keyboard Examples

Example 1: Simple Key Detection

//#CLIENTSIDE
function onKeyPressed() {
    if (keydown(5)) { // S key
        player.chat = "Attack button pressed!";
    }
    if (keydown(6)) { // A key
        player.chat = "Grab button pressed!";
    }
}

Example 2: Custom Movement System

//#CLIENTSIDE
function onKeyPressed() {
    setTimer(0.05); // Start checking for held keys
}

function onTimeout() {
    temp.moved = false;

    // Loop through directional keys (0-3)
    for (temp.i = 0; temp.i < 4; temp.i++) {
        if (keydown(temp.i)) {
            // Move player in that direction
            player.x += vecx(temp.i);
            player.y += vecy(temp.i);
            temp.moved = true;
        }
    }

    // Continue looping if still moving
    if (temp.moved) {
        setTimer(0.05);
    }
}

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Mouse Input

Mouse Events

onMouseDown(mousevalue)

Triggers when a mouse button is pressed:

//#CLIENTSIDE
function onMouseDown(mousevalue) {
    if (mousevalue == "left") {
        player.chat = "Left click at: " @ mousex @ ", " @ mousey;
    }
    if (mousevalue == "right") {
        player.chat = "Right click detected!";
    }
}

onMouseUp(mousevalue)

Triggers when a mouse button is released:

//#CLIENTSIDE
function onMouseUp(mousevalue) {
    if (mousevalue == "left") {
        player.chat = "Left mouse button released!";
    }
}

Mouse Values

Mouse Value	Description
"left"	Left mouse button
"right"	Right mouse button
"middle"	Middle mouse button
"double"	Double-left click

Mouse Variables

Variable	Type	Description
leftmousebutton	boolean	True if left button is held down
rightmousebutton	boolean	True if right button is held down
middlemousebutton	boolean	True if middle button is held down
mousex	float	Mouse X position in world coordinates
mousey	float	Mouse Y position in world coordinates
mousescreenx	integer	Mouse X position on screen
mousescreeny	integer	Mouse Y position on screen
mousewheeldelta	integer	Mouse wheel scroll amount

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Mouse Examples

Example 1: Click to Place Blocks

//#CLIENTSIDE
function onCreated() {
    this.counter = 0;
}

function onMouseDown(mousevalue) {
    if (mousevalue == "left") {
        // Place a block at mouse position
        showimg(200 + this.counter, "block.png", mousex - 1, mousey - 1);
        this.counter++;
        if (this.counter > 20) this.counter = 0; // Reuse image IDs
    }
}

Example 2: Interactive Block with Mouse

//#CLIENTSIDE
function onCreated() {
    // Create a block that follows the mouse
    temp.img = showimg(200, "block.png", mousescreenx - 16, mousescreeny - 16);
    temp.img.layer = 4;
    setTimer(0.05);
}

function onTimeout() {
    // Update block position to follow mouse
    with (findimg(200)) {
        x = mousescreenx;
        y = mousescreeny;
    }

    // Left click: Make block larger
    if (leftmousebutton) {
        findimg(200).zoom += 0.05;
    }

    // Right click: Make block smaller
    if (rightmousebutton) {
        findimg(200).zoom -= 0.05;
    }

    // Middle click: Rotate block
    if (middlemousebutton) {
        findimg(200).rotation += 0.05;
    }

    setTimer(0.05);
}

Example 3: Drawing System

//#CLIENTSIDE
function onCreated() {
    this.drawing = false;
    this.drawCounter = 0;
}

function onMouseDown(mousevalue) {
    if (mousevalue == "left") {
        this.drawing = true;
        setTimer(0.05);
    }
}

function onMouseUp(mousevalue) {
    if (mousevalue == "left") {
        this.drawing = false;
    }
}

function onTimeout() {
    if (this.drawing && leftmousebutton) {
        // Draw dots where the mouse is
        temp.dot = showimg(300 + this.drawCounter, "dot.png", mousex, mousey);
        temp.dot.alpha = 0.8;

        this.drawCounter++;
        if (this.drawCounter > 100) this.drawCounter = 0;

        setTimer(0.05);
    }
}

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Advanced Techniques

Combining Keyboard and Mouse

//#CLIENTSIDE
function onCreated() {
    this.mode = "normal";
    setTimer(0.05);
}

function onTimeout() {
    // Hold SHIFT (or any key) for different behavior
    if (keydown(5)) { // S key held
        this.mode = "attack";
    } else {
        this.mode = "normal";
    }

    // Mouse behavior changes based on mode
    if (leftmousebutton) {
        if (this.mode == "attack") {
            // Attack at mouse position
            shootfireball(player.dir);
        } else {
            // Normal interaction
            player.chat = "Clicked at: " @ mousex @ ", " @ mousey;
        }
    }

    setTimer(0.05);
}

Input Validation

//#CLIENTSIDE
function onMouseDown(mousevalue) {
    // Only allow clicks within a certain area
    if (mousex >= 10 && mousex <= 50 && mousey >= 10 && mousey <= 50) {
        player.chat = "Valid click area!";
    } else {
        player.chat = "Click inside the designated area!";
    }
}

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Remember: Input handling is what makes games feel responsive and fun. Practice these examples and experiment with different combinations to create engaging interactive experiences!