Add minimal Gizmo Material (#43)

This is a small feature push that adds a simple Shader for the Gizmo.
This shader only takes one value: the color of the object. Very simple
and fast to compile.

This PR is missing:
- Shader Pre Compiling. This is something that I am looking into now,
however I thought it out of scope for this feature.

Just thought I would drop this real fast. Let me know what y'all think!

---------

Co-authored-by: Danny McGee <dannymcgee@gmail.com>

studio/assets/shaders/gizmo.wgsl

@@ -0,0 +1,9 @@
+#import bevy_pbr::forward_io::VertexOutput
+
+@group(1) @binding(0)
+var<uniform> material_color: vec4<f32>;
+
+@fragment
+fn fragment(mesh: VertexOutput) -> @location(0) vec4<f32> {
+    return material_color;
+}

studio/src/interaction/gizmos/common.rs

@@ -3,6 +3,8 @@ use bevy_mod_picking::prelude::*;
 
 use crate::interaction::TransformSpace;
 
+use super::material::GizmoMaterial;
+
 #[derive(Component, Reflect)]
 pub(super) struct TransformGizmo {
     pub(super) target: Entity,
@@ -67,18 +69,18 @@ impl TransformGizmoBundle {
 
 pub(super) fn on_gizmo_element_hover(
     ev: Listener<Pointer<Over>>,
-    mut ra_mats: ResMut<Assets<StandardMaterial>>,
-    q_target: Query<&Handle<StandardMaterial>>,
+    mut ra_mats: ResMut<Assets<GizmoMaterial>>,
+    q_target: Query<&Handle<GizmoMaterial>>,
 ) {
     let mat = ra_mats.get_mut(q_target.get(ev.target).unwrap()).unwrap();
-    mat.base_color *= 2.;
+    mat.color *= 2.;
 }
 
 pub(super) fn on_gizmo_element_unhover(
     ev: Listener<Pointer<Out>>,
-    mut ra_mats: ResMut<Assets<StandardMaterial>>,
-    q_target: Query<&Handle<StandardMaterial>>,
+    mut ra_mats: ResMut<Assets<GizmoMaterial>>,
+    q_target: Query<&Handle<GizmoMaterial>>,
 ) {
     let mat = ra_mats.get_mut(q_target.get(ev.target).unwrap()).unwrap();
-    mat.base_color *= 0.5;
+    mat.color *= 0.5;
 }

studio/src/interaction/gizmos/material.rs

@@ -0,0 +1,31 @@
+use bevy::{
+    prelude::*,
+    render::render_resource::{AsBindGroup, ShaderRef},
+};
+
+#[derive(Asset, TypePath, AsBindGroup, Debug, Clone)]
+pub struct GizmoMaterial {
+    #[uniform(0)]
+    pub color: Color,
+
+    pub blend_mode: AlphaMode,
+}
+
+impl From<Color> for GizmoMaterial {
+    fn from(color: Color) -> Self {
+        GizmoMaterial {
+            color,
+            blend_mode: AlphaMode::Blend,
+        }
+    }
+}
+
+impl Material for GizmoMaterial {
+    fn fragment_shader() -> ShaderRef {
+        "shaders/gizmo.wgsl".into()
+    }
+
+    fn alpha_mode(&self) -> AlphaMode {
+        self.blend_mode
+    }
+}

studio/src/interaction/gizmos/mod.rs

@@ -6,6 +6,7 @@ use self::{
     camera::{spawn_gizmo_camera, GizmoCamera},
     combo::spawn_combo_translation_rotation_gizmo,
     common::*,
+    material::GizmoMaterial,
     resources::{init_resources, GizmoMats, GizmoMeshes},
     rotation::{spawn_rotation_gizmo, update_ss_ring_rotation},
     translation::spawn_translation_gizmo,
@@ -16,6 +17,7 @@ use super::{Selection, TransformMode, TransformType};
 pub mod camera;
 mod combo;
 mod common;
+mod material;
 mod resources;
 mod rotation;
 mod translation;
@@ -70,6 +72,9 @@ impl Plugin for GizmoPlugin {
             PostUpdate,
             update_ss_ring_rotation.after(TransformSystem::TransformPropagate),
         );
+
+        //This is the material code for the gizmo material
+        app.add_plugins(MaterialPlugin::<GizmoMaterial>::default());
     }
 }
 

studio/src/interaction/gizmos/resources.rs

@@ -2,6 +2,8 @@ use bevy::prelude::*;
 
 use crate::{design_system, math::geo};
 
+use super::material::GizmoMaterial;
+
 #[derive(Resource, Reflect, Debug, Default)]
 #[reflect(Resource)]
 pub(super) struct GizmoMeshes {
@@ -17,24 +19,24 @@ pub(super) struct GizmoMeshes {
 #[derive(Resource, Reflect, Debug, Default)]
 #[reflect(Resource)]
 pub(super) struct GizmoMats {
-    pub translate_x: Handle<StandardMaterial>,
-    pub translate_y: Handle<StandardMaterial>,
-    pub translate_z: Handle<StandardMaterial>,
-    pub translate_yz: Handle<StandardMaterial>,
-    pub translate_xz: Handle<StandardMaterial>,
-    pub translate_xy: Handle<StandardMaterial>,
-    pub translate_ss: Handle<StandardMaterial>,
-    pub rotate_x: Handle<StandardMaterial>,
-    pub rotate_y: Handle<StandardMaterial>,
-    pub rotate_z: Handle<StandardMaterial>,
-    pub rotate_trackball: Handle<StandardMaterial>,
-    pub rotate_ss: Handle<StandardMaterial>,
+    pub translate_x: Handle<GizmoMaterial>,
+    pub translate_y: Handle<GizmoMaterial>,
+    pub translate_z: Handle<GizmoMaterial>,
+    pub translate_yz: Handle<GizmoMaterial>,
+    pub translate_xz: Handle<GizmoMaterial>,
+    pub translate_xy: Handle<GizmoMaterial>,
+    pub translate_ss: Handle<GizmoMaterial>,
+    pub rotate_x: Handle<GizmoMaterial>,
+    pub rotate_y: Handle<GizmoMaterial>,
+    pub rotate_z: Handle<GizmoMaterial>,
+    pub rotate_trackball: Handle<GizmoMaterial>,
+    pub rotate_ss: Handle<GizmoMaterial>,
 }
 
 pub(super) fn init_resources(
     mut cmd: Commands,
     mut ra_meshes: ResMut<Assets<Mesh>>,
-    mut ra_mats: ResMut<Assets<StandardMaterial>>,
+    mut ra_mats: ResMut<Assets<GizmoMaterial>>,
 ) {
     let translate_line = ra_meshes.add(Mesh::from(shape::Cylinder {
         radius: 0.03,
@@ -86,71 +88,22 @@ pub(super) fn init_resources(
         rotate_ss,
     });
 
-    let translate_x = ra_mats.add(StandardMaterial {
-        base_color: design_system::Color::RED,
-        unlit: true,
-        ..default()
-    });
-    let translate_yz = ra_mats.add(StandardMaterial {
-        base_color: design_system::Color::RED,
-        unlit: true,
-        ..default()
-    });
+    let translate_x = ra_mats.add(design_system::Color::RED.into());
+    let translate_yz = ra_mats.add(design_system::Color::RED.into());
 
-    let translate_y = ra_mats.add(StandardMaterial {
-        base_color: design_system::Color::GREEN,
-        unlit: true,
-        ..default()
-    });
-    let translate_xz = ra_mats.add(StandardMaterial {
-        base_color: design_system::Color::GREEN,
-        unlit: true,
-        ..default()
-    });
+    let translate_y = ra_mats.add(design_system::Color::GREEN.into());
+    let translate_xz = ra_mats.add(design_system::Color::GREEN.into());
 
-    let translate_z = ra_mats.add(StandardMaterial {
-        base_color: design_system::Color::BLUE,
-        unlit: true,
-        ..default()
-    });
-    let translate_xy = ra_mats.add(StandardMaterial {
-        base_color: design_system::Color::BLUE,
-        unlit: true,
-        ..default()
-    });
+    let translate_z = ra_mats.add(design_system::Color::BLUE.into());
+    let translate_xy = ra_mats.add(design_system::Color::BLUE.into());
 
-    let translate_ss = ra_mats.add(StandardMaterial {
-        base_color: Color::WHITE,
-        unlit: true,
-        ..default()
-    });
+    let translate_ss = ra_mats.add(Color::WHITE.into());
 
-    let rotate_x = ra_mats.add(StandardMaterial {
-        base_color: design_system::Color::RED,
-        unlit: true,
-        ..default()
-    });
-    let rotate_y = ra_mats.add(StandardMaterial {
-        base_color: design_system::Color::GREEN,
-        unlit: true,
-        ..default()
-    });
-    let rotate_z = ra_mats.add(StandardMaterial {
-        base_color: design_system::Color::BLUE,
-        unlit: true,
-        ..default()
-    });
-    let rotate_trackball = ra_mats.add(StandardMaterial {
-        base_color: Color::NONE,
-        emissive: Color::WHITE,
-        alpha_mode: AlphaMode::Add,
-        ..default()
-    });
-    let rotate_ss = ra_mats.add(StandardMaterial {
-        base_color: Color::WHITE,
-        unlit: true,
-        ..default()
-    });
+    let rotate_x = ra_mats.add(design_system::Color::RED.into());
+    let rotate_y = ra_mats.add(design_system::Color::GREEN.into());
+    let rotate_z = ra_mats.add(design_system::Color::BLUE.into());
+    let rotate_trackball = ra_mats.add(Color::WHITE.with_a(0.0).into());
+    let rotate_ss = ra_mats.add(Color::WHITE.into());
 
     cmd.insert_resource(GizmoMats {
         translate_x,

studio/src/interaction/gizmos/rotation.rs

@@ -14,8 +14,8 @@ use crate::{
 };
 
 use super::{
-    on_gizmo_element_hover, on_gizmo_element_unhover, GizmoMats, GizmoMeshes, InitialTransform,
-    TransformGizmo, TransformGizmoBundle, GIZMO_RENDER_LAYER,
+    material::GizmoMaterial, on_gizmo_element_hover, on_gizmo_element_unhover, GizmoMats,
+    GizmoMeshes, InitialTransform, TransformGizmo, TransformGizmoBundle, GIZMO_RENDER_LAYER,
 };
 
 #[derive(Component)]
@@ -159,20 +159,20 @@ pub(super) fn update_ss_ring_rotation(
 
 fn on_trackball_hover(
     ev: Listener<Pointer<Over>>,
-    mut ra_mats: ResMut<Assets<StandardMaterial>>,
-    q_target: Query<&Handle<StandardMaterial>>,
+    mut ra_mats: ResMut<Assets<GizmoMaterial>>,
+    q_target: Query<&Handle<GizmoMaterial>>,
 ) {
     let mat = ra_mats.get_mut(q_target.get(ev.target).unwrap()).unwrap();
-    mat.base_color.set_a(0.2);
+    mat.color.set_a(0.05);
 }
 
 fn on_trackball_unhover(
     ev: Listener<Pointer<Out>>,
-    mut ra_mats: ResMut<Assets<StandardMaterial>>,
-    q_target: Query<&Handle<StandardMaterial>>,
+    mut ra_mats: ResMut<Assets<GizmoMaterial>>,
+    q_target: Query<&Handle<GizmoMaterial>>,
 ) {
     let mat = ra_mats.get_mut(q_target.get(ev.target).unwrap()).unwrap();
-    mat.base_color.set_a(0.);
+    mat.color.set_a(0.);
 }
 
 pub(super) fn on_rotation_start(