Added directional light from sun

simulator/src/main.rs

@@ -1,5 +1,5 @@
-use cgmath::Rotation3;
+use cgmath::{Rotation3, Vector3};
-use solar_engine::{Application, Body, Key, KeyState, Simulator};
+use solar_engine::{Application, Body, Key, KeyState, Light, LightType, Simulator};
 use std::sync::{Arc, RwLock};
 use std::thread;
 
@@ -47,14 +47,34 @@ pub async fn run() {
             let sim = simulator_clone.read().unwrap();
             let bodies = &sim.bodies;
 
+            let sun_pos = Vector3::new(
+                (bodies[0].position[0] / 1.496e11) as f32,
+                (bodies[0].position[1] / 1.496e11) as f32,
+                0.0,
+            );
+
+            let light_offset = Vector3::new(0.0, 0.0, 0.1);
+
+            state.light_manager.clear();
+            state.light_manager.add_light(Light {
+                position: sun_pos + light_offset,
+                direction: Vector3::new(0.0, 0.0, 0.0),
+                color: Vector3::from([1.0, 1.0, 0.8]),
+                intensity: 5.0,
+                range: 0.0,
+                inner_cutoff: 0.0,
+                light_type: LightType::Directional,
+                outer_cutoff: 0.0,
+            });
+
             let instances = bodies
                 .iter()
                 .enumerate()
                 .map(|(i, b)| {
                     solar_engine::RenderInstance {
-                        position: cgmath::Vector3::new(
+                        position: Vector3::new(
-                            (b.position[0] / 1.496e11) as f32,
+                            ((b.position[0] / 1.496e11) as f32) - sun_pos.x,
-                            (b.position[1] / 1.496e11) as f32,
+                            ((b.position[1] / 1.496e11) as f32) - sun_pos.y,
                             0.0,
                         ),
                         rotation: cgmath::Quaternion::from_angle_z(cgmath::Deg(0.0)),

solar_engine/src/lib.rs

@@ -5,6 +5,7 @@ mod render;
 mod application;
 mod input;
 mod camera;
+mod light;
 
 pub use body::Body;
 
@@ -22,3 +23,6 @@ pub use input::Key;
 pub use input::map_winit_key;
 pub use input::InputEvent;
 pub use input::KeyState;
+
+pub use light::Light;
+pub use light::LightType;

solar_engine/src/light.rs

@@ -0,0 +1,118 @@
+use bytemuck::{Pod, Zeroable};
+use cgmath::Vector3;
+
+#[repr(u32)]
+#[derive(Clone, Copy, Debug)]
+pub enum LightType {
+    Directional = 0,
+    Point = 1,
+    Spot = 2
+}
+
+#[repr(C)]
+#[derive(Clone, Copy, Pod, Zeroable, Debug)]
+pub struct GpuLight {
+    pub position: [f32; 3],
+    pub light_type: u32,
+    pub color: [f32; 3],
+    pub intensity: f32,
+    pub direction: [f32; 3],
+    pub range: f32,
+    pub inner_cutoff: f32,
+    pub outer_cutoff: f32,
+}
+
+pub struct Light {
+    pub light_type: LightType,
+    pub position: Vector3<f32>,
+    pub direction: Vector3<f32>,
+    pub color: Vector3<f32>,
+    pub intensity: f32,
+    pub range: f32,
+    pub inner_cutoff: f32,
+    pub outer_cutoff: f32,
+}
+
+impl Light {
+    pub fn to_gpu(&self) -> GpuLight {
+        GpuLight {
+            position: self.position.into(),
+            light_type: self.light_type as u32,
+            color: self.color.into(),
+            intensity: self.intensity,
+            direction: self.direction.into(),
+            range: self.range,
+            inner_cutoff: self.inner_cutoff,
+            outer_cutoff: self.outer_cutoff,
+        }
+    }
+}
+
+pub struct LightManager {
+    pub lights: Vec<Light>,
+    pub buffer: wgpu::Buffer,
+    pub bind_group: wgpu::BindGroup,
+    pub layout: wgpu::BindGroupLayout,
+}
+
+impl LightManager {
+    pub fn new(device: &wgpu::Device, max_lights: usize) -> Self {
+        let buffer = device.create_buffer(&wgpu::BufferDescriptor {
+            label: Some("Light Buffer"),
+            size: (max_lights * size_of::<GpuLight>()) as wgpu::BufferAddress,
+            usage: wgpu::BufferUsages::UNIFORM | wgpu::BufferUsages::COPY_DST,
+            mapped_at_creation: false,
+        });
+
+        let layout = device.create_bind_group_layout(&wgpu::BindGroupLayoutDescriptor {
+            label: Some("Light Bind Group Layout"),
+            entries: &[wgpu::BindGroupLayoutEntry {
+                binding: 0,
+                visibility: wgpu::ShaderStages::VERTEX_FRAGMENT,
+                ty: wgpu::BindingType::Buffer {
+                    ty: wgpu::BufferBindingType::Uniform,
+                    has_dynamic_offset: false,
+                    min_binding_size: None,
+                },
+                count: None,
+            }],
+        });
+
+        let bind_group = device.create_bind_group(&wgpu::BindGroupDescriptor {
+            label: Some("Light Bind Group"),
+            layout: &layout,
+            entries: &[wgpu::BindGroupEntry {
+                binding: 0,
+                resource: buffer.as_entire_binding(),
+            }],
+        });
+
+        Self {
+            lights: Vec::new(),
+            buffer,
+            bind_group,
+            layout,
+        }
+    }
+
+    pub fn add_light(&mut self, light: Light) {
+        self.lights.push(light);
+    }
+
+    pub fn update_gpu(&self, queue: &wgpu::Queue) {
+        let data: Vec<GpuLight> = self.lights.iter().map(|l| l.to_gpu()).collect();
+        queue.write_buffer(&self.buffer, 0, bytemuck::cast_slice(&data));
+    }
+
+    pub fn bind_group(&self) -> &wgpu::BindGroup {
+        &self.bind_group
+    }
+
+    pub fn layout(&self) -> &wgpu::BindGroupLayout {
+        &self.layout
+    }
+    
+    pub fn clear(&mut self) {
+        self.lights.clear();
+    }
+}

solar_engine/src/render.rs

@@ -6,7 +6,6 @@ pub struct Globals {
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
 pub enum Shape {
-    Polygon,
     Circle,
     Sphere,
 }
@@ -74,11 +73,12 @@ impl SampleCount {
 pub struct Vertex {
     pub(crate) position: [f32; 3],
     pub(crate) color: [f32; 3],
+    pub(crate) normal: [f32; 3],
 }
 
 impl Vertex {
-    const ATTRIBS: [wgpu::VertexAttribute; 2] =
+    const ATTRIBS: [wgpu::VertexAttribute; 3] =
-        wgpu::vertex_attr_array![0 => Float32x3, 1 => Float32x3];
+        wgpu::vertex_attr_array![0 => Float32x3, 1 => Float32x3, 2 => Float32x3];
 
     pub(crate) fn desc() -> wgpu::VertexBufferLayout<'static> {
         wgpu::VertexBufferLayout {
@@ -90,14 +90,22 @@ impl Vertex {
 }
 
 pub fn create_circle_vertices(segment_count: usize, radius: f32, color: [f32; 3]) -> (Vec<Vertex>, Vec<u16>) {
-    let mut vertices = vec![Vertex { position: [0.0, 0.0, 0.0], color }];
+    let mut vertices = vec![Vertex {
+        position: [0.0, 0.0, 0.0],
+        color,
+        normal: [0.0, 0.0, 1.0],
+    }];
     let mut indices = vec![];
 
     for i in 0..=segment_count {
         let theta = (i as f32) / (segment_count as f32) * std::f32::consts::TAU;
         let x = radius * theta.cos();
         let y = radius * theta.sin();
-        vertices.push(Vertex { position: [x, y, 0.0], color });
+        vertices.push(Vertex {
+            position: [x, y, 0.0],
+            color,
+            normal: [0.0, 0.0, 1.0],
+        });
     }
 
     for i in 1..=segment_count {
@@ -123,9 +131,12 @@ pub fn create_sphere_vertices(stacks: usize, slices: usize, radius: f32, color:
             let x = r * theta.cos();
             let z = r * theta.sin();
 
+            let normal = [x, y, z];
+
             vertices.push(Vertex {
                 position: [x * radius, y * radius, z * radius],
                 color,
+                normal,
             });
         }
     }

solar_engine/src/shader.wgsl

@@ -1,6 +1,7 @@
 struct VertexInput {
     @location(0) position: vec3<f32>,
     @location(1) color: vec3<f32>,
+    @location(2) normal: vec3<f32>,
 };
 
 struct InstanceInput {
@@ -13,7 +14,9 @@ struct InstanceInput {
 
 struct VSOutput {
     @builtin(position) position: vec4<f32>,
-    @location(0) color: vec3<f32>,
+    @location(0) frag_color: vec3<f32>,
+    @location(1) world_pos: vec3<f32>,
+    @location(2) normal: vec3<f32>,
 };
 
 struct Globals {
@@ -23,21 +26,52 @@ struct Globals {
 @group(0) @binding(0)
 var<uniform> globals: Globals;
 
+struct GpuLight {
+    position: vec3<f32>,
+    color: vec3<f32>,
+    intensity: f32,
+};
+
+@group(1) @binding(0)
+var<uniform> lights: array<GpuLight, 10>;
+
 @vertex
 fn vs_main(vertex: VertexInput, instance: InstanceInput) -> VSOutput {
     var out: VSOutput;
+
     let model = mat4x4<f32>(
         instance.model_row0,
         instance.model_row1,
         instance.model_row2,
         instance.model_row3
     );
-    out.position = globals.view_proj * model * vec4<f32>(vertex.position, 1.0);
+
-    out.color = instance.color;
+    let world_position = (model * vec4<f32>(vertex.position, 1.0)).xyz;
+    let normal_matrix = mat3x3<f32>(
+        instance.model_row0.xyz,
+        instance.model_row1.xyz,
+        instance.model_row2.xyz
+    );
+
+    out.position = globals.view_proj * vec4<f32>(world_position, 1.0);
+    out.frag_color = instance.color * vertex.color;
+    out.world_pos = world_position;
+    out.normal = normalize(normal_matrix * vertex.normal);
+
     return out;
 }
 
 @fragment
 fn fs_main(input: VSOutput) -> @location(0) vec4<f32> {
-    return vec4<f32>(input.color, 1.0);
+    var lighting: vec3<f32> = vec3<f32>(0.0);
+
+    for (var i = 0u; i < 10u; i = i + 1u) {
+        let light = lights[i];
+        let light_dir = normalize(light.position - input.world_pos);
+        let diff = max(dot(input.normal, light_dir), 0.0);
+        lighting += light.color * light.intensity * diff;
+    }
+
+    let final_color = input.frag_color * lighting;
+    return vec4<f32>(final_color, 1.0);
 }

solar_engine/src/state.rs

@@ -9,6 +9,7 @@ use wgpu::{Adapter, Device, Instance, PresentMode, Queue, Surface, SurfaceCapabi
 use winit::dpi::PhysicalSize;
 use winit::window::{Window};
 use crate::camera::Camera;
+use crate::light::{GpuLight, LightManager};
 use crate::render::{create_circle_vertices, create_sphere_vertices, Geometry, Globals, InstanceRaw, RenderInstance, SampleCount, Shape, Vertex};
 
 pub struct State<'a> {
@@ -32,6 +33,8 @@ pub struct State<'a> {
 
     camera: Camera,
     depth_texture: wgpu::TextureView,
+
+    pub light_manager: LightManager,
 }
 
 impl<'a> State<'a> {
@@ -83,7 +86,9 @@ impl<'a> State<'a> {
             label: Some("Global Bind Group"),
         });
 
-        let render_pipeline = Self::create_render_pipeline(&device, &config, sample_count.0, &global_bind_group_layout);
+        let light_manager = LightManager::new(&device, 10);
+
+        let render_pipeline = Self::create_render_pipeline(&device, &config, sample_count.0, &global_bind_group_layout, &light_manager);
         let geometries = Self::create_geometries(&device);
 
         let instances = vec![];
@@ -112,9 +117,15 @@ impl<'a> State<'a> {
             instance_buffer,
             camera,
             depth_texture,
+            light_manager
         }
     }
 
+    fn update_lights(&mut self) {
+        let light_data: Vec<GpuLight> = self.light_manager.lights.iter().map(|l| l.to_gpu()).collect();
+        self.queue.write_buffer(&self.light_manager.buffer, 0, bytemuck::cast_slice(&light_data));
+    }
+
     fn create_depth_texture(device: &Device, width: u32, height: u32, sample_count: u32) -> wgpu::TextureView {
         let texture = device.create_texture(&wgpu::TextureDescriptor {
             label: Some("Depth Texture"),
@@ -136,18 +147,6 @@ impl<'a> State<'a> {
     fn create_geometries(device: &Device) -> HashMap<Shape, Geometry> {
         let mut geometries = HashMap::new();
 
-        let polygon_vertices = vec![
-            Vertex { position: [-0.0868241, 0.49240386, 0.0], color: [0.5, 0.0, 0.5] },
-            Vertex { position: [-0.49513406, 0.06958647, 0.0], color: [0.5, 0.0, 0.5] },
-            Vertex { position: [-0.21918549, -0.44939706, 0.0], color: [0.5, 0.0, 0.5] },
-            Vertex { position: [0.35966998, -0.3473291, 0.0], color: [0.5, 0.0, 0.5] },
-            Vertex { position: [0.44147372, 0.2347359, 0.0], color: [0.5, 0.0, 0.5] },
-        ];
-        let polygon_indices = vec![0, 1, 4, 1, 2, 4, 2, 3, 4];
-
-        let polygon_geometry = Self::create_geometry(device, &polygon_vertices, &polygon_indices);
-        geometries.insert(Shape::Polygon, polygon_geometry);
-
         let (circle_vertices, circle_indices) = create_circle_vertices(512, 0.5, [0.5, 0.5, 0.5]);
         let circle_geometry = Self::create_geometry(device, &circle_vertices, &circle_indices);
         geometries.insert(Shape::Circle, circle_geometry);
@@ -207,7 +206,7 @@ impl<'a> State<'a> {
         })
     }
     
-    fn create_render_pipeline(device: &Device, config: &SurfaceConfiguration, sample_count: u32, global_bind_group_layout: &wgpu::BindGroupLayout) -> wgpu::RenderPipeline {
+    fn create_render_pipeline(device: &Device, config: &SurfaceConfiguration, sample_count: u32, global_bind_group_layout: &wgpu::BindGroupLayout, light_manager: &LightManager) -> wgpu::RenderPipeline {
         let shader = device.create_shader_module(wgpu::ShaderModuleDescriptor {
             label: Some("Shader"),
             source: wgpu::ShaderSource::Wgsl(include_str!("shader.wgsl").into()),
@@ -216,7 +215,7 @@ impl<'a> State<'a> {
         let render_pipeline_layout =
             device.create_pipeline_layout(&wgpu::PipelineLayoutDescriptor {
                 label: Some("Render Pipeline Layout"),
-                bind_group_layouts: &[&global_bind_group_layout],
+                bind_group_layouts: &[&global_bind_group_layout, &light_manager.layout],
                 push_constant_ranges: &[],
             });
 
@@ -394,6 +393,10 @@ impl<'a> State<'a> {
             render_pass.set_pipeline(&self.render_pipeline);
             render_pass.set_bind_group(0, &self.global_bind_group, &[]);
             
+            // Update the light manager buffer
+            self.light_manager.update_gpu(&self.queue);
+            render_pass.set_bind_group(1, &self.light_manager.bind_group, &[]);
+
             for shape in self.geometries.keys().copied() {
                 let geometry = &self.geometries[&shape];