MouseEvent

Represents a mouse input event.

A mouse event is dispatched when the cursor moves, a button is pressed or released, or the scroll wheel is used. It extends the base Event with data specific to mouse input: the interaction type, the cursor position, and optional button information.

Mouse events are dispatched through the Scene hierarchy where nodes can override the Node::OnMouseEvent handler and optionally mark the event as handled. When handled is set to true the event stops propagating to other nodes.

class MyNode : public vglx::Node {
public:
  auto OnMouseEvent(vglx::MouseEvent* event) -> void override {
    if (event->type == vglx::MouseEvent::Type::ButtonPressed) {
      if (event->button == vglx::MouseButton::Left) {
        // Do something...
        event->handled = true; // stop propagation
      }
    }
  }
};

INFO

Derives from Event and inherits all public properties and methods.

Types

MouseEvent::Type enum

Enumerates all mouse event types.

Distinguishes between cursor movement, button transitions, and scroll actions. Engines that support continuous mouse tracking or gesture recognition should implement those behaviors at a higher layer.

Value	Description
Moved	Cursor moved.
ButtonPressed	Button transitioned to the down state.
ButtonReleased	Button transitioned to the up state.
Scrolled	Scroll wheel moved.

Properties

button MouseButton

Mouse button associated with the event, if any.

Identifies which button triggered the event using the mouse button enumeration. Refer to the source code for enum details.

MouseButton button {};

mods int

Modifier keys active during this mouse event.

Indicates which keyboard modifiers were held at the time the event was generated. Multiple modifiers may be active depending on platform and input backend. Refer to the source code for enum details.

int mods {};

position Vector2

Current cursor position in window coordinates.

The coordinate origin is always the top-left corner of the window: X increases to the right and Y increases downward.

Vector2 position {0.0f, 0.0f};

scroll Vector2

Scroll delta since the last scroll event.

The delta is expressed in abstract scroll units normalized such that positive Y values represent upward scrolling.

Vector2 scroll {0.0f, 0.0f};

type MouseEvent::Type

The interaction type for this event.

MouseEvent::Type type {};

window_size Vector2

Size of the window's client area in window coordinates.

Shares the coordinate space of position, so it can be used to normalize cursor positions or drag deltas.

Vector2 window_size {0.0f, 0.0f};

Functions

GetType() Event::Type virtual

Identifies this event as Event::Type::Mouse.

Type vglx::MouseEvent::GetType() const override;