| 43 | } |
| 44 | |
| 45 | fn logic(engine: &mut Engine, _: &mut GameState) { |
| 46 | if let Some(sprite) = engine.sprites.get_mut("Race Car") { |
| 47 | // Use the latest state of the mouse buttons to rotate the sprite |
| 48 | let mut rotation_amount = 0.0; |
| 49 | if engine.mouse_state.pressed(MouseButton::Left) { |
| 50 | rotation_amount += ROTATION_SPEED * engine.delta_f32; |
| 51 | } |
| 52 | if engine.mouse_state.pressed(MouseButton::Right) { |
| 53 | rotation_amount -= ROTATION_SPEED * engine.delta_f32; |
| 54 | } |
| 55 | sprite.rotation += rotation_amount; |
| 56 | |
| 57 | // Use the latest state of the mouse wheel to scale the sprite |
| 58 | if let Some(location) = engine.mouse_state.location() { |
| 59 | sprite.translation = location |
| 60 | } |
| 61 | |
| 62 | // Honestly, this is probably the one "state" thing that you should ignore in favor of |
| 63 | // processing each event instead (see the mouse_events example), since you can then handle |
| 64 | // fast spins of the wheel. But here is how to use the mouse wheel state sort of like a |
| 65 | // button. `wheel_direction` will be `1.0`, `0.0`, or `-1.0` depending on what's going on |
| 66 | // with the mouse wheel. |
| 67 | let wheel_direction = engine.mouse_state.wheel().y; |
| 68 | sprite.scale *= 1.0 + (wheel_direction * 0.1); |
| 69 | sprite.scale = sprite.scale.clamp(0.1, 4.0); |
| 70 | } |
| 71 | |
| 72 | // Offset the move indicator from the move indicator origin to visually represent the relative |
| 73 | // mouse motion for the frame |
| 74 | if let Some(sprite) = engine.sprites.get_mut("move indicator") { |
| 75 | let motion = engine.mouse_state.motion(); |
| 76 | // There seems to be a Bevy 0.6 bug where every other frame we don't receive any mouse |
| 77 | // motion events, so ignore those frames. |
| 78 | // TODO: Follow up on this bug in upstream Bevy |
| 79 | if motion != Vec2::ZERO { |
| 80 | sprite.translation = motion + Vec2::from(ORIGIN_LOCATION); |
| 81 | } |
| 82 | } |
| 83 | } |