How do objects move along curved lines?

hey,

how to move objects along curved lines from a to b using mouse click objects?

Generally speaking, objects can move along curved lines by utilizing the same data/method you used to draw the line in the first place.

There are many ways to draw or describe a curved line in different situations. How are you making your line?

For example, from what you said in your post, it sounds like you want to click a, and then click b, and have a curved line appear. But how do you determine if the line is curved to the left or the right, and how wide?

Sorry I mean like drag the mouse so this is an example

So I drag the blue object with the mouse to point B and the blue object only can follows a curved line.

if i use drag and drop i can drag it everywhere because i have a path for the object so the object can only drag in the existing path.

it is a lot harder than you would think...

this is an old sample I made a couple years ago in C2. It doesn't seem to work with the C3 runtime, so if you load in into C3 you have to go into the advanced project properties and choose the C2 runtime.

the project links a bunch of dots into a line and forces the object you drag to follow the line. the more dots you add. the better the curve would look.

https://www.rieperts.com/games/forum/DragAlongLine.capx

there are other ways to do this - if you have an equation for the line, then you can calculate a point anywhere along the line. Or if the curve is a segment of a circle you can use sin and cos to calculate where the blue square should be...

i think the example before to hard how about this.

this is still same project

i just want to drag the arrow to blank circle

Maybe this demo will be useful?

howtoconstructdemos.com/draw-a-path-on-the-screen-and-move-your-character-along-it

i think i can't use it, because it's automatic following the line. how about drag the sprites to the target.

ok, I used the image of the slider, and Dop's qarp calculation. But instead of three sprite objects to define the curve, I added image points to the slider graphic where the A, B, and C boxes would go to make the curve work. I also clamp the touch X value so the circle part of the slider can't go past the ends.

if you drop the circle and it is not close enough to the end point, it resets back to its starting position.

https://www.rieperts.com/games/forum/Slider.c3p

Here's another idea to add into the mix of clever ideas posted in this topic.

You can define any path as a bunch of points. Between two consecutive points are lines. Then with a bit of math (vector projection) we can find the spot on a line closest to a point. We can then use that to move along that line, and when we move off the ends of the line we can make it switch to the next or previous lines.

dropbox.com/s/njck4ai7ebh2ivr/drag_along_path.capx