D-Pad and Buttons

Read digital button presses from the player-one controller. GoSprite64 polls controller state once per frame automatically, so these functions always reflect the current frame's input.

import gs "github.com/drpaneas/gosprite64"

Button constants

The N64 controller has 14 digital buttons. Each constant is a ButtonMask bitmask, so you can combine them with bitwise OR when needed.

Checking held buttons

IsButtonDown returns true for every frame the button is physically held down:

func (g *Game) Update() {
    if gs.IsButtonDown(gs.ButtonDPadRight) {
        player.X += speed
    }
    if gs.IsButtonDown(gs.ButtonDPadLeft) {
        player.X -= speed
    }
    if gs.IsButtonDown(gs.ButtonDPadUp) {
        player.Y -= speed
    }
    if gs.IsButtonDown(gs.ButtonDPadDown) {
        player.Y += speed
    }
}

Use IsButtonDown for continuous actions like movement - the callback fires every frame while the button is pressed.

Detecting a fresh press

IsButtonJustPressed returns true only on the first frame the button transitions from released to pressed. It will not fire again until the player releases and re-presses the button.

func (g *Game) Update() {
    if gs.IsButtonJustPressed(gs.ButtonA) {
        player.Jump()
    }
    if gs.IsButtonJustPressed(gs.ButtonB) {
        player.Attack()
    }
    if gs.IsButtonJustPressed(gs.ButtonStart) {
        g.TogglePause()
    }
}

Use IsButtonJustPressed for one-shot actions like jumping, attacking, or opening a menu - actions that should not repeat while the button is held.

Combining both

A common pattern uses IsButtonJustPressed for the initial action and IsButtonDown for sustained behavior:

func (g *Game) Update() {
    // Charge attack: start on press, charge while held
    if gs.IsButtonJustPressed(gs.ButtonB) {
        player.StartCharge()
    }
    if gs.IsButtonDown(gs.ButtonB) {
        player.AddCharge(1)
    }

    // D-Pad movement (continuous)
    if gs.IsButtonDown(gs.ButtonDPadRight) {
        player.X += 2
    }

    // Menu navigation (one tap per press)
    if gs.IsButtonJustPressed(gs.ButtonDPadDown) {
        menu.MoveDown()
    }
}

Port-zero convenience

IsButtonDown and IsButtonJustPressed read from controller port 0 (the first controller). For multiplayer input, see Multi-Controller Support.