5acebed731
Transform and GlobalTransform are now Similarities. This resolves precision errors and simplifies the api Co-authored-by: Carter Anderson <mcanders1@gmail.com>
54 lines
1.5 KiB
Rust
54 lines
1.5 KiB
Rust
use super::Node;
|
|
use bevy_ecs::{Entity, Query, With, Without};
|
|
use bevy_transform::{
|
|
hierarchy,
|
|
prelude::{Children, Parent, Transform},
|
|
};
|
|
|
|
pub const UI_Z_STEP: f32 = 0.001;
|
|
|
|
pub fn ui_z_system(
|
|
mut root_node_query: Query<With<Node, Without<Parent, Entity>>>,
|
|
mut node_query: Query<(Entity, &Node, &mut Transform)>,
|
|
children_query: Query<&Children>,
|
|
) {
|
|
let mut current_global_z = 0.0;
|
|
|
|
// PERF: we can probably avoid an allocation here by making root_node_query and node_query non-overlapping
|
|
let root_nodes = (&mut root_node_query.iter())
|
|
.iter()
|
|
.collect::<Vec<Entity>>();
|
|
|
|
for entity in root_nodes {
|
|
if let Some(result) = hierarchy::run_on_hierarchy(
|
|
&children_query,
|
|
&mut node_query,
|
|
entity,
|
|
Some(current_global_z),
|
|
Some(current_global_z),
|
|
&mut update_node_entity,
|
|
) {
|
|
current_global_z = result;
|
|
}
|
|
}
|
|
}
|
|
|
|
fn update_node_entity(
|
|
node_query: &mut Query<(Entity, &Node, &mut Transform)>,
|
|
entity: Entity,
|
|
parent_result: Option<f32>,
|
|
previous_result: Option<f32>,
|
|
) -> Option<f32> {
|
|
let mut z = UI_Z_STEP;
|
|
let parent_global_z = parent_result.unwrap();
|
|
if let Some(previous_global_z) = previous_result {
|
|
z += previous_global_z - parent_global_z;
|
|
};
|
|
let global_z = z + parent_global_z;
|
|
|
|
let mut transform = node_query.get_mut::<Transform>(entity).ok()?;
|
|
transform.translation.set_z(z);
|
|
|
|
Some(global_z)
|
|
}
|