From ad05e6d1f2d38dcb016a570e999bfaeef96665ce Mon Sep 17 00:00:00 2001
From: RustyStriker <avivr903@tutanota.com>
Date: Wed, 24 Aug 2022 23:03:11 +0300
Subject: [PATCH] grid size scale with zoom

---
 assets/shaders/grid.wgsl | 49 ++++++++++++++++++++++++++++++++++++++++
 src/infinite_grid.rs     |  8 +++++--
 2 files changed, 55 insertions(+), 2 deletions(-)

diff --git a/assets/shaders/grid.wgsl b/assets/shaders/grid.wgsl
index 947434c..f7c6b54 100644
--- a/assets/shaders/grid.wgsl
+++ b/assets/shaders/grid.wgsl
@@ -8,6 +8,55 @@ let grid_color: vec4<f32> = vec4<f32>(1.0, 1.0, 1.0, 0.3);
 let x_color: vec4<f32> = vec4<f32>(1.0, 0.0, 0.0, 1.0);
 let y_color :vec4<f32> = vec4<f32>(0.0, 1.0, 0.0, 1.0);
 
+
+#import bevy_sprite::mesh2d_view_bindings
+#import bevy_sprite::mesh2d_bindings
+
+// NOTE: Bindings must come before functions that use them!
+#import bevy_sprite::mesh2d_functions
+
+struct Vertex {
+    @location(0) position: vec3<f32>,
+    @location(1) normal: vec3<f32>,
+    @location(2) uv: vec2<f32>,
+#ifdef VERTEX_TANGENTS
+    @location(3) tangent: vec4<f32>,
+#endif
+#ifdef VERTEX_COLORS
+    @location(4) color: vec4<f32>,
+#endif
+    @builtin(vertex_index) index: u32,
+};
+
+struct VertexOutput {
+    @builtin(position) clip_position: vec4<f32>,
+    #import bevy_sprite::mesh2d_vertex_output
+}
+
+@vertex
+fn vertex(vertex: Vertex) -> VertexOutput {
+    var out: VertexOutput;
+    out.uv = vertex.uv;
+    out.world_position = mesh2d_position_local_to_world(mesh.model, vec4<f32>(vertex.position, 1.0));
+    out.clip_position = mesh2d_position_world_to_clip(out.world_position);
+    var grid_plane = array<vec3<f32>, 4>(
+        vec3<f32>(-1., -1., 1.),
+        vec3<f32>(-1., 1., 1.),
+        vec3<f32>(1., -1., 1.),
+        vec3<f32>(1., 1., 1.)
+    );
+    out.clip_position = vec4<f32>(grid_plane[vertex.index].xyz, 1.0);
+
+    out.world_normal = mesh2d_normal_local_to_world(vertex.normal);
+#ifdef VERTEX_TANGENTS
+    out.world_tangent = mesh2d_tangent_local_to_world(vertex.tangent);
+#endif
+#ifdef VERTEX_COLORS
+    out.color = vertex.color;
+#endif
+    return out;
+}
+
 @fragment
 fn fragment(
     @builtin(position) position: vec4<f32>,
diff --git a/src/infinite_grid.rs b/src/infinite_grid.rs
index c270a9d..e60b10b 100644
--- a/src/infinite_grid.rs
+++ b/src/infinite_grid.rs
@@ -29,8 +29,8 @@ pub fn spawn_grid(
 ) {
 
     coms.spawn().insert_bundle(MaterialMesh2dBundle {
-        mesh: meshes.add(Mesh::from(shape::Cube { size: 1000.0 })).into(),
-        transform: Transform::from_xyz(0.0, 0.0, 0.0),
+        mesh: meshes.add(Mesh::from(shape::Plane { size: 1000.0 })).into(),
+        transform: Transform::from_rotation(Quat::from_rotation_x(std::f32::consts::FRAC_PI_2)),
         material: mats.add(GridMaterial { width: 2.0, size: Vec2::splat(15.0), visible: 1 }),
         ..default()
     });
@@ -40,11 +40,15 @@ pub fn update_grid_shader(
     snap_grid: Res<crate::SnapGrid>,
     handles: Query<&Handle<GridMaterial>>,
     mut mats: ResMut<Assets<GridMaterial>>,
+    projection: Query<&OrthographicProjection, With<MainCamera>>,
 ) {
+    let zoom = projection.get_single().map(|p| p.scale).unwrap_or(1.0);
+
     for h in handles.iter() {
         if let Some(mut m) = mats.get_mut(h) {
             m.size = Vec2::new(snap_grid.width, snap_grid.height);
             m.visible = snap_grid.visible as u32;
+            m.width = zoom;
         }
     }
 }