Slow Glass Sprite Movement Actions
These commands affect the position and movement of a named sprite.
Move
move {sprite-name}(by |
to) {x} {y} [(in | at) {duration}]` |
Moves the sprite to the given location (to} or to a location relative to the existing location (by). This can happen immediately or over a given duration.
The locations, x and y are integers - they can be negative and can out outside the currently visible area.
The command completes when the movement has been accomplished.
Scroll
If the sprite was created with a view (i.e. a “window” on to the underlying texture then you can use the following command on it:
scroll {sprite-name} by {x} {y} [pixels per second]
scroll {sprite-name} stop
Whilst this does NOT (strictly speaking) move the sprite it does move the _content- of the sprite which can have a similar effect, for example moving clouds across the sky.
If the scrolled window reaches the edge of the underlying texture then it will be repeated as a mirror repeat and hence may appear seemless. If you want ot take advantage of this then use tileable textures.
Rotate
rotate {sprite-name} (by | to | at) {angle} [in {duration}]
Rotates the sprite arounds its centre by, or to the specified angle. The angle is in degrees with zero pointing upwards and the angle increasing clock wise.
The command completes when the rotation is accomplished.
Throw / Drop
(throw | launch) {sprite-name} [at] {angle} [with force {speed}]
throw {sprite-name} stop
These commands work in conjunction with the directives “gravity” and “geound”. TODO Add link
This will cause the sprite to start moving as if under the influence of gravity. Angle is in degrees, with zero upwards and increasing clockwise. Speed is given in pixels per second in the scene coordinates (and will be scaled to match the display coordinates scheme).
The sprite will travel until one of three conditions is met:
- it goes “out of bounds” (by default, more than twice the display size in any direction)
- it goes below the ground level as specified in the directive above
- It is explicitly stopped
Sprite location is measured at the centre of the sprite, not its bounds.
Drop is a convenience command equivalent to throw something at 180 degrees with zero speed.
Although these commands involve moving sprites I think it makes more sense to have the commands complete immediately.
Jiggle
(jiggle | jitter) {sprite-name} [by] {x} {y} {step} [with chance {percentage}]
(jiggle | jitter) stop
This command makes the sprite move in a random walk around its actual position. It will never go more than x or y pixels in either direction, and each step will be no larger than step pixels. The position is updated 25 times per second and will only happen if a random percentage is less than percentage, default 100%, i.e. jiggling every 25th of a second. A percentage of 50 or even lower looks quite effective.
When the sprite position is used, for example in a variable or moving by a relative amount then the intended position is used, the jigglyness is ignored for these purposes.
The command completes immediately although jiggling will continue until the stop command
Sway / Wave
(sway | wave) {sprite-name} [to] {degrees} [in] {duration} [with chance {percentage}]
(sway | wave) stop
This makes a gradual adjustment to the skew angle, going up to the skew angle in the given time, down to zero then to the negative angle in the given time, and repeats. The difference between them is that sway operates in the x axis and wave operates in the y axis. You can apply both at the same time.
The percentage chance determines whether a movement will be made at each update (currently once every 25th of a second).
The sway and wave are calculated separately from any other skew value applied, and if you skew a relative amount, or use the skew value in a variable any extra amount of sway or wave will be ignored.
The command completes immediately although skewing will continue until the stop command
Future Intentions
To have the ability to change the centre of rotation, e.g.
rotate {sprite-name} to 45 around 50 50