I'm not sure if this is a bug, or its intended purpose, but when you set a Sprite to invisible, GetSpriteHit still returns the invisiblt Sprite.

For example, I am using a Sprite as a button, and although I have set it to invisible, if I click the area where the button would be displayed (if it wasn't invisible), GetSpriteHit returns the sprite id. Surely if the Sprite is invisible you shouldn't be able to click it? No?

What do you think?

Hmmm... I've found a work around, simply look for the visibility first using GetSpriteVisible...



Thanks all the same...

Invisible sprites can be usefull, if you walk into an invisible wall, it still hurts, You should move the sprite to some unused coordinates, like -5000,-5000 if it should not be "active", and move it back when you need it again. You can also use the setspriteactive command, but I'm not sure how it will work with collisions and physics, I had problem using the virtual button active/inactive command, so I use the -5000,-5000 trick.

In a project I made for a class, invisible sprites were used for a ton of things.

Detecting whether the player was in line-of-sight of an enemy (no raycasting functions in the language I was using, and it was an introductory course, so I didn't know how to do it myself yet)

Detecting whether the player sprite was in a particular position so an event could trigger.

Plopping down a "Hey, AI, the explosion will be this big" invisible sprite so if they detect that they collide with the sprite they'll try to avoid the explosion.

A "use item" invis-sprite next to the player sprite which checked if usable items collided with it when the player hit the button.

Probably should use Zone Collision in lieu of Invisible Sprites for a lot of this stuff.
http://www.appgamekit.com/documentation/examples/sprites/11_zone_collision.htm

Although I still need invisible sprites or hidden sprites when flipping around stuff. But the above would be good if say your character falls into a lava trap.

I'm just moving my sprites off-screen, as impetus73 suggested. It's even saving me some commands, as a SetSpritePosition() takes the place of both SetSpriteVisible() and SetSpriteActive().