worn forum
I don't quite understand how extrusion works, I could extrude and turn into a mesh for some primitive 2D shapes but not others:
e.g. Here I can create an extrusion but I get error on the last line because it can't be converted to a mesh
let l: Line2d = Line2d { direction: Dir2::X };
let e = Extrusion::new(l, 4.0)
meshes.add(e)
Do I need to do something else to turn this into a mesh? whats the point in being able to turn it into an Extrusion if I can't turn it into a mesh after?
glacial latch
Although you could extrude a line, I feel like you'd need a direction instead of just a depth. Lines don't have a natural "normal" direction like say a plane or triangle does. Also when it was extruded, what would it generate? A plane, right? You'd have to extrude twice to get an actual 3d shape from a line.
worn forum
Thanks for your response!
It would not graphically generate anything is the problem
On meshes.add(e), I would get error:
the trait From<bevy::prelude::Extrusion<bevy::prelude::Line2d>> is not implemented for bevy::prelude::Mesh, which is required by bevy::prelude::Extrusion<bevy::prelude::Line2d>: Into<bevy::prelude::Mesh>
worn forum
Although you could extrude a line, I feel like you'd need a direction instead of...
How should I do the extrusion twice?
glacial latch
I don’t think you can extrude twice. I’d suggest you create the Rectangle directly instead of extruding from a line. Then extrude that.
worn forum
I don’t think you can extrude twice. I’d suggest you create the Rectangle direct...
Is there a way I can create arbitrary 2d shapes and extrude that?
glacial latch
Yeah, try using Polygon.
worn forum
Yeah, try using Polygon.
Is this what you were referring to?
https://docs.rs/bevy/latest/bevy/math/prelude/struct.RegularPolygon.html
It seems to only be able to do regular shapes and not irregular ones
Also, found this plugin, this seems to do more or less what I was looking for
Is this possible to do without a plugin?
https://github.com/nilaysavant/bevy_mesh_drawing
worn forum
https://docs.rs/bevy/latest/bevy/math/prelude/struct.Polygon.html
This gives me a similar error to what I began with, the extrusion can not be turned into a mesh:
let points2d = vec!
[
vec2(-6., 2.),
vec2(-2., 4.),
vec2(-3., 5.)
];
let p = Polygon::new(points2d);
let e = Extrusion::new(p, 2.0);
let mesh_handle: Handle<Mesh> = meshes.add(e);
The error message:
the trait From<bevy::prelude::Extrusion<bevy::prelude::Polygon<_>>> is not implemented for bevy::prelude::Mesh, which is required by bevy::prelude::Extrusion<bevy::prelude::Polygon<_>>: Into<bevy::prelude::Mesh>
glacial latch
Hmm. Looks like it's not implemented for Polygon. Huh. https://docs.rs/bevy/latest/bevy/render/mesh/trait.Extrudable.html
Maybe they don't want to deal with non-convex or intersecting boundaries, but it seems like those ought to look fine with extrusion.
worn forum
Maybe they don't want to deal with non-convex or intersecting boundaries, but it...
Sorry, what do you mean by non-convex?
glacial latch
In a convex shape, a line between any two points within the shape never crosses to the outside. A circle is convex; a circle with a missing quadrant is not convex. It's a really nice property mathematically.
Personally I think added Polygon support would make for a good pull request.
worn forum
What would be wrong with creating extrusions on non-convex shapes?
glacial latch
Nothing visually, but maybe there's a complication for dealing with bounds or ray casting that I'm not aware of.
worn forum
Hmmm interesting, I follow what you are saying but idk enough about gamedev to think about this more or create a pull request haha
glacial latch
Yeah, I'd just use the crate you linked to and see if that'll work for you.
You can be assured that the very reasonable thing you want to do isn't supported in bevy yet.
worn forum
Ah okay, no worries thanks for your effor!