use crate::{
extract_resource::ExtractResource,
render_resource::{ShaderType, UniformBuffer},
renderer::{RenderDevice, RenderQueue},
Extract, RenderApp, RenderStage,
};
use bevy_app::{App, Plugin};
use bevy_core::FrameCount;
use bevy_ecs::prelude::*;
use bevy_reflect::Reflect;
use bevy_time::Time;
pub struct GlobalsPlugin;
impl Plugin for GlobalsPlugin {
fn build(&self, app: &mut App) {
if let Ok(render_app) = app.get_sub_app_mut(RenderApp) {
render_app
.init_resource::<GlobalsBuffer>()
.init_resource::<Time>()
.add_system_to_stage(RenderStage::Extract, extract_time)
.add_system_to_stage(RenderStage::Prepare, prepare_globals_buffer);
}
}
}
fn extract_time(mut commands: Commands, time: Extract<Res<Time>>) {
commands.insert_resource(time.clone());
}
#[derive(Default, Clone, Resource, ExtractResource, Reflect, ShaderType)]
#[reflect(Resource)]
pub struct GlobalsUniform {
time: f32,
delta_time: f32,
frame_count: u32,
#[cfg(feature = "webgl")]
_wasm_padding: f32,
}
#[derive(Resource, Default)]
pub struct GlobalsBuffer {
pub buffer: UniformBuffer<GlobalsUniform>,
}
fn prepare_globals_buffer(
render_device: Res<RenderDevice>,
render_queue: Res<RenderQueue>,
mut globals_buffer: ResMut<GlobalsBuffer>,
time: Res<Time>,
frame_count: Res<FrameCount>,
) {
let buffer = globals_buffer.buffer.get_mut();
buffer.time = time.elapsed_seconds_wrapped();
buffer.delta_time = time.delta_seconds();
buffer.frame_count = frame_count.0;
globals_buffer
.buffer
.write_buffer(&render_device, &render_queue);
}