Change flat flag to enum.

src/computed.rs

@@ -1,10 +1,12 @@
 use bevy::prelude::*;
 
+use crate::uniforms::DepthMode;
+
 /// A component for storing the computed depth at which the outline lies.
 #[derive(Clone, Component, Default)]
 pub struct ComputedOutlineDepth {
-    pub(crate) origin: Vec3,
-    pub(crate) flat: bool,
+    pub(crate) world_origin: Vec3,
+    pub(crate) depth_mode: DepthMode,
 }
 
 /// A component which specifies how the outline depth should be computed.
@@ -37,21 +39,22 @@ pub(crate) fn compute_outline_depth(
     child_query: Query<(&Children, Changed<Children>)>,
 ) {
     for (mut computed, transform, changed_transform, set_depth, children) in root_query.iter_mut() {
-        let mut changed = computed.is_added() || changed_transform || set_depth.filter(|(_, c)| *c).is_some();
+        let mut changed =
+            computed.is_added() || changed_transform || set_depth.filter(|(_, c)| *c).is_some();
         if changed {
-            let (origin, flat) = if let Some((sd, _)) = set_depth {
+            let (origin, depth_mode) = if let Some((sd, _)) = set_depth {
                 match sd {
                     SetOutlineDepth::Flat {
                         model_origin: origin,
-                    } => (*origin, true),
-                    SetOutlineDepth::Real => (Vec3::NAN, false),
+                    } => (*origin, DepthMode::Flat),
+                    SetOutlineDepth::Real => (Vec3::NAN, DepthMode::Real),
                 }
             } else {
-                (Vec3::ZERO, true)
+                (Vec3::ZERO, DepthMode::Flat)
             };
             let matrix = transform.compute_matrix();
-            computed.origin = matrix.project_point3(origin);
-            computed.flat = flat;
+            computed.world_origin = matrix.project_point3(origin);
+            computed.depth_mode = depth_mode;
         }
         if let Some((cs, changed_children)) = children {
             changed |= changed_children;

src/draw.rs

@@ -65,7 +65,7 @@ pub(crate) fn queue_outline_stencil_mesh(
             if let Some(mesh) = render_meshes.get(mesh_handle) {
                 let key = base_key
                     .with_primitive_topology(mesh.primitive_topology)
-                    .with_flat_depth(stencil_flags.flat_depth)
+                    .with_depth_mode(stencil_flags.depth_mode)
                     .with_offset_zero(stencil_uniform.offset == 0.0);
                 let pipeline = pipelines
                     .specialize(&mut pipeline_cache, &stencil_pipeline, key, &mesh.layout)
@@ -145,7 +145,7 @@ pub(crate) fn queue_outline_volume_mesh(
                     } else {
                         PassType::Opaque
                     })
-                    .with_flat_depth(volume_flags.flat_depth)
+                    .with_depth_mode(volume_flags.depth_mode)
                     .with_offset_zero(volume_uniform.offset == 0.0);
                 let pipeline = pipelines
                     .specialize(&mut pipeline_cache, &outline_pipeline, key, &mesh.layout)

src/pipeline.rs

@@ -22,7 +22,9 @@ use bevy::{
 };
 use bitfield::{bitfield_bitrange, bitfield_fields};
 
-use crate::uniforms::{OutlineFragmentUniform, OutlineStencilUniform, OutlineVolumeUniform};
+use crate::uniforms::{
+    DepthMode, OutlineFragmentUniform, OutlineStencilUniform, OutlineVolumeUniform,
+};
 use crate::view_uniforms::OutlineViewUniform;
 use crate::ATTRIBUTE_OUTLINE_NORMAL;
 
@@ -49,8 +51,8 @@ impl PipelineKey {
         msaa_samples_minus_one, set_msaa_samples_minus_one: 5, 0;
         primitive_topology_int, set_primitive_topology_int: 8, 6;
         pass_type_int, set_pass_type_int: 10, 9;
-        pub flat_depth, set_flat_depth: 11;
-        pub offset_zero, set_offset_zero: 12;
+        depth_mode_int, set_depth_mode_int: 12, 11;
+        pub offset_zero, set_offset_zero: 13;
     }
 
     pub(crate) fn new() -> Self {
@@ -101,10 +103,18 @@ impl PipelineKey {
         self
     }
 
-    pub(crate) fn with_flat_depth(mut self, flat_depth: bool) -> Self {
-        self.set_flat_depth(flat_depth);
+    pub(crate) fn with_depth_mode(mut self, depth_mode: DepthMode) -> Self {
+        self.set_depth_mode_int(depth_mode as u32);
         self
     }
+
+    pub(crate) fn depth_mode(&self) -> DepthMode {
+        match self.depth_mode_int() {
+            x if x == DepthMode::Flat as u32 => DepthMode::Flat,
+            x if x == DepthMode::Real as u32 => DepthMode::Real,
+            x => panic!("Invalid value for DepthMode: {}", x),
+        }
+    }
 }
 
 #[derive(Resource)]
@@ -214,7 +224,7 @@ impl SpecializedMeshPipeline for OutlinePipeline {
         );
         bind_layouts.push(self.outline_view_bind_group_layout.clone());
         let cull_mode;
-        if key.flat_depth() {
+        if key.depth_mode() == DepthMode::Flat {
             vertex_defs.push("FLAT_DEPTH".to_string());
             cull_mode = Some(Face::Back);
         } else if key.pass_type() == PassType::Stencil {

src/uniforms.rs

@@ -35,14 +35,22 @@ pub(crate) struct OutlineFragmentUniform {
     pub colour: Vec4,
 }
 
+#[derive(Clone, Copy, Default, PartialEq)]
+pub(crate) enum DepthMode {
+    #[default]
+    Invalid = 0,
+    Flat = 1,
+    Real = 2,
+}
+
 #[derive(Component)]
 pub(crate) struct OutlineStencilFlags {
-    pub flat_depth: bool,
+    pub depth_mode: DepthMode,
 }
 
 #[derive(Component)]
 pub(crate) struct OutlineVolumeFlags {
-    pub flat_depth: bool,
+    pub depth_mode: DepthMode,
 }
 
 #[derive(Resource)]
@@ -63,11 +71,11 @@ pub(crate) fn extract_outline_stencil_uniforms(
         commands
             .get_or_spawn(entity)
             .insert(OutlineStencilUniform {
-                origin: computed.origin,
+                origin: computed.world_origin,
                 offset: stencil.offset,
             })
             .insert(OutlineStencilFlags {
-                flat_depth: computed.flat,
+                depth_mode: computed.depth_mode,
             });
     }
 }
@@ -83,14 +91,14 @@ pub(crate) fn extract_outline_volume_uniforms(
         commands
             .get_or_spawn(entity)
             .insert(OutlineVolumeUniform {
-                origin: computed.origin,
+                origin: computed.world_origin,
                 offset: outline.width,
             })
             .insert(OutlineFragmentUniform {
                 colour: outline.colour.as_linear_rgba_f32().into(),
             })
             .insert(OutlineVolumeFlags {
-                flat_depth: computed.flat,
+                depth_mode: computed.depth_mode,
             });
     }
 }