rendering code and api crate

crates/bevy_xr/src/camera.rs

@@ -0,0 +1,102 @@
+use bevy::app::{App, Plugin};
+use bevy::core_pipeline::core_3d::graph::Core3d;
+use bevy::core_pipeline::core_3d::Camera3d;
+use bevy::core_pipeline::tonemapping::{DebandDither, Tonemapping};
+use bevy::ecs::bundle::Bundle;
+use bevy::ecs::component::Component;
+use bevy::ecs::reflect::ReflectComponent;
+use bevy::math::{Mat4, Vec3A};
+use bevy::reflect::Reflect;
+use bevy::render::camera::{
+    Camera, CameraMainTextureUsages, CameraProjection, CameraProjectionPlugin, CameraRenderGraph,
+    Exposure,
+};
+use bevy::render::primitives::Frustum;
+use bevy::render::view::{ColorGrading, VisibleEntities};
+use bevy::transform::components::{GlobalTransform, Transform};
+
+pub struct XrCameraPlugin;
+
+impl Plugin for XrCameraPlugin {
+    fn build(&self, app: &mut App) {
+        app.add_plugins(CameraProjectionPlugin::<XrProjection>::default());
+    }
+}
+
+#[derive(Clone, Copy, Component, Reflect, Debug)]
+#[reflect(Component)]
+pub struct XrProjection {
+    pub projection_matrix: Mat4,
+    pub near: f32,
+    pub far: f32,
+}
+
+impl Default for XrProjection {
+    fn default() -> Self {
+        Self {
+            near: 0.1,
+            far: 1000.,
+            projection_matrix: Mat4::IDENTITY,
+        }
+    }
+}
+
+/// Marker component for an XR view. It is the backends responsibility to update this.
+#[derive(Clone, Copy, Component, Debug, Default)]
+pub struct XrView;
+
+impl CameraProjection for XrProjection {
+    fn get_projection_matrix(&self) -> Mat4 {
+        self.projection_matrix
+    }
+
+    fn update(&mut self, _width: f32, _height: f32) {}
+
+    fn far(&self) -> f32 {
+        self.far
+    }
+
+    // TODO calculate this properly
+    fn get_frustum_corners(&self, _z_near: f32, _z_far: f32) -> [Vec3A; 8] {
+        Default::default()
+    }
+}
+
+#[derive(Bundle)]
+pub struct XrCameraBundle {
+    pub camera: Camera,
+    pub camera_render_graph: CameraRenderGraph,
+    pub projection: XrProjection,
+    pub visible_entities: VisibleEntities,
+    pub frustum: Frustum,
+    pub transform: Transform,
+    pub global_transform: GlobalTransform,
+    pub camera_3d: Camera3d,
+    pub tonemapping: Tonemapping,
+    pub dither: DebandDither,
+    pub color_grading: ColorGrading,
+    pub exposure: Exposure,
+    pub main_texture_usages: CameraMainTextureUsages,
+    pub view: XrView,
+}
+
+impl Default for XrCameraBundle {
+    fn default() -> Self {
+        Self {
+            camera_render_graph: CameraRenderGraph::new(Core3d),
+            camera: Default::default(),
+            projection: Default::default(),
+            visible_entities: Default::default(),
+            frustum: Default::default(),
+            transform: Default::default(),
+            global_transform: Default::default(),
+            camera_3d: Default::default(),
+            tonemapping: Default::default(),
+            color_grading: Default::default(),
+            exposure: Default::default(),
+            main_texture_usages: Default::default(),
+            dither: DebandDither::Enabled,
+            view: XrView,
+        }
+    }
+}