Spotlight feature

src/controller.rs

@@ -1,4 +1,7 @@
-use winit::event::{MouseButton, MouseScrollDelta, WindowEvent};
+use winit::{
+	event::{ElementState, MouseButton, MouseScrollDelta, WindowEvent},
+	keyboard::{Key, NamedKey},
+};
 
 use crate::camera::Camera;
 
@@ -12,9 +15,10 @@ pub struct CameraController {
 	cursor_start: (f32, f32),
 	movement: (f32, f32),
 	is_moving: bool,
+	is_ctrl_pressed: bool,
 
 	movement_total: (f32, f32),
-	zoom_total: f32,
+	pub zoom_total: f32,
 }
 
 impl CameraController {
@@ -27,6 +31,7 @@ impl CameraController {
 			cursor_start: (0.0, 0.0),
 			movement: (0.0, 0.0),
 			is_moving: false,
+			is_ctrl_pressed: false,
 
 			movement_total: (0.0, 0.0),
 			zoom_total: 1.0,
@@ -80,20 +85,33 @@ impl CameraController {
 			}
 			WindowEvent::MouseWheel { delta, .. } => match delta {
 				MouseScrollDelta::LineDelta(_, y) => {
+					if !self.is_ctrl_pressed {
 						self.zoom_total += y;
 						if self.zoom_total >= 0.0 && self.zoom_total <= MAX_ZOOM_LEVEL {
 							self.zoom = *y;
 						}
 						self.zoom_total = self.zoom_total.clamp(0.0, MAX_ZOOM_LEVEL);
+					}
 					true
 				}
 				_ => false,
 			},
+			WindowEvent::KeyboardInput { event, .. } => {
+				self.is_ctrl_pressed = false;
+				if event.state == ElementState::Pressed {
+					let key = &event.logical_key;
+					if let Key::Named(NamedKey::Control) = key {
+						self.is_ctrl_pressed = true;
+					}
+				}
+				true
+			}
+
 			_ => false,
 		}
 	}
 
-	pub fn update_camera(&mut self, camera: &mut Camera) {
+	pub fn update(&mut self, camera: &mut Camera) {
 		use cgmath::InnerSpace;
 
 		let forward = camera.target - camera.eye;

src/lib.rs

@@ -4,6 +4,7 @@ use winit::event_loop::{ControlFlow, EventLoop};
 pub mod app;
 pub mod camera;
 pub mod controller;
+pub mod spotlight;
 pub mod state;
 pub mod texture;
 pub mod vertex;

src/shader.wgsl

@@ -29,12 +29,27 @@ fn vs_main(
 
 // Fragment shader
 
+struct SpotlightUniform {
+	cursor_position: vec2<f32>,
+	size: f32,
+	zoom_level: f32,
+	strength: f32
+}
+
 @group(0) @binding(0)
 var t_diffuse: texture_2d<f32>;
 @group(0) @binding(1)
 var s_diffuse: sampler;
+@group(2) @binding(0)
+var<uniform> spotlight: SpotlightUniform;
 
 @fragment
 fn fs_main(in: VertexOutput) -> @location(0) vec4<f32> {
-     return textureSample(t_diffuse, s_diffuse, in.tex_coords);
+	var cursor4 = vec4<f32>(spotlight.cursor_position, 0.0, 1.0);
+	var texColor = textureSample(t_diffuse, s_diffuse, in.tex_coords);
+	var shadowColor = vec4<f32>(0.0, 0.0, 0.0, 1.0);
+	var dist_check = length(cursor4 - in.position) < (spotlight.size * spotlight.zoom_level);
+	var spotlightColor = select(spotlight.strength, 0.0, dist_check);
+	var finalColor = mix(texColor, shadowColor, spotlightColor);
+	return finalColor;
 }

src/spotlight.rs

@@ -0,0 +1,124 @@
+use wgpu::util::DeviceExt;
+use winit::{
+	event::{ElementState, MouseScrollDelta, WindowEvent},
+	keyboard::{Key, NamedKey},
+};
+
+use crate::controller::CameraController;
+
+pub struct Spotlight {
+	cursor_position: (f32, f32),
+	size: f32,
+
+	is_ctrl_pressed: bool,
+}
+
+pub struct SpotlightInfo {
+	pub uniform: SpotlightUniform,
+	pub buffer: wgpu::Buffer,
+	pub layout: wgpu::BindGroupLayout,
+	pub bind_group: wgpu::BindGroup,
+}
+
+impl Spotlight {
+	pub fn new(device: &wgpu::Device) -> (Self, SpotlightInfo) {
+		let spotlight = Self {
+			cursor_position: (960.0, 540.0),
+			size: 50.0,
+
+			is_ctrl_pressed: false,
+		};
+
+		let layout = device.create_bind_group_layout(&wgpu::BindGroupLayoutDescriptor {
+			entries: &[wgpu::BindGroupLayoutEntry {
+				binding: 0,
+				visibility: wgpu::ShaderStages::FRAGMENT,
+				ty: wgpu::BindingType::Buffer {
+					ty: wgpu::BufferBindingType::Uniform,
+					has_dynamic_offset: false,
+					min_binding_size: None,
+				},
+				count: None,
+			}],
+			label: Some("spotlight_bind_group_layout"),
+		});
+
+		let uniform = SpotlightUniform {
+			cursor_position: [0.0, 0.0],
+			size: 50.0,
+			zoom_level: 1.0,
+			strength: 0.0,
+			padding: 0.0,
+		};
+
+		let buffer = device.create_buffer_init(&wgpu::util::BufferInitDescriptor {
+			label: Some("Spotlight Buffer"),
+			contents: bytemuck::cast_slice(&[uniform]),
+			usage: wgpu::BufferUsages::UNIFORM | wgpu::BufferUsages::COPY_DST,
+		});
+
+		let bind_group = device.create_bind_group(&wgpu::BindGroupDescriptor {
+			layout: &layout,
+			entries: &[wgpu::BindGroupEntry {
+				binding: 0,
+				resource: buffer.as_entire_binding(),
+			}],
+			label: Some("spotlight_bind_group"),
+		});
+
+		let info = SpotlightInfo {
+			layout,
+			bind_group,
+			buffer,
+			uniform,
+		};
+
+		(spotlight, info)
+	}
+
+	pub fn process_events(&mut self, event: &WindowEvent) {
+		match event {
+			WindowEvent::CursorMoved { position, .. } => {
+				self.cursor_position = (position.x as f32, position.y as f32);
+			}
+			WindowEvent::KeyboardInput { event, .. } => {
+				self.is_ctrl_pressed = false;
+				if event.state == ElementState::Pressed {
+					let key = &event.logical_key;
+					if let Key::Named(NamedKey::Control) = key {
+						self.is_ctrl_pressed = true;
+					}
+				}
+			}
+			WindowEvent::MouseWheel { delta, .. } => {
+				if let MouseScrollDelta::LineDelta(_, y) = delta {
+					if self.is_ctrl_pressed {
+						self.size += y * 5.0;
+					}
+				}
+			}
+			_ => {}
+		}
+	}
+
+	pub fn update(&mut self) {}
+}
+
+#[repr(C)]
+#[derive(Debug, Copy, Clone, bytemuck::Pod, bytemuck::Zeroable)]
+pub struct SpotlightUniform {
+	cursor_position: [f32; 2],
+	size: f32,
+	zoom_level: f32,
+	strength: f32,
+	padding: f32,
+}
+
+impl SpotlightUniform {
+	pub fn update(&mut self, spotlight: &Spotlight, controller: &CameraController) {
+		self.cursor_position = [spotlight.cursor_position.0, spotlight.cursor_position.1];
+		self.size = spotlight.size;
+		self.zoom_level = controller.zoom_total.max(1.0);
+		self.strength = if spotlight.is_ctrl_pressed { 0.9 } else { 0.0 };
+	}
+}

src/state.rs

@@ -1,7 +1,7 @@
 use std::sync::Arc;
 
 use pollster::FutureExt;
-use wgpu::util::DeviceExt;
+use wgpu::{util::DeviceExt, DynamicOffset};
 use winit::{
 	event::{ElementState, WindowEvent},
 	keyboard::Key,
@@ -11,6 +11,7 @@ use winit::{
 use crate::{
 	camera::{Camera, CameraInfo},
 	controller::CameraController,
+	spotlight::{Spotlight, SpotlightInfo},
 	texture::Texture,
 	vertex::Vertex,
 };
@@ -54,9 +55,11 @@ pub struct State<'a> {
 	render_pipeline: wgpu::RenderPipeline,
 	vertex_buffer: wgpu::Buffer,
 	index_buffer: wgpu::Buffer,
-	bind_group: wgpu::BindGroup,
+	texture_bind_group: wgpu::BindGroup,
 	pub camera: Camera,
 	pub camera_info: CameraInfo,
+	pub spotlight: Spotlight,
+	pub spotlight_info: SpotlightInfo,
 	pub zoom: f32,
 	pub camera_controller: CameraController,
 }
@@ -117,6 +120,8 @@ impl<'a> State<'a> {
 		let (camera, camera_info) = Camera::new(&config, &device);
 		let camera_controller = CameraController::new(ZOOM_SPEED, MOVE_SPEED);
 
+		let (spotlight, spotlight_info) = Spotlight::new(&device);
+
 		let shader = device.create_shader_module(wgpu::include_wgsl!("shader.wgsl"));
 
 		let texture = Texture::new(image, &device, &queue);
@@ -124,7 +129,7 @@ impl<'a> State<'a> {
 		let render_pipeline_layout =
 			device.create_pipeline_layout(&wgpu::PipelineLayoutDescriptor {
 				label: Some("Render Pipeline Layout"),
-				bind_group_layouts: &[&texture.layout, &camera_info.layout],
+				bind_group_layouts: &[&texture.layout, &camera_info.layout, &spotlight_info.layout],
 				push_constant_ranges: &[],
 			});
 
@@ -192,9 +197,11 @@ impl<'a> State<'a> {
 			render_pipeline,
 			vertex_buffer,
 			index_buffer,
-			bind_group: texture.group,
+			texture_bind_group: texture.bind_group,
 			camera,
 			camera_info,
+			spotlight,
+			spotlight_info,
 			camera_controller,
 			zoom: 1.0,
 		}
@@ -212,6 +219,7 @@ impl<'a> State<'a> {
 
 	pub fn input(&mut self, event: &winit::event::WindowEvent) -> bool {
 		self.camera_controller.process_events(self.wsize, event);
+		self.spotlight.process_events(event);
 		match event {
 			WindowEvent::KeyboardInput {
 				event: key_event, ..
@@ -232,13 +240,24 @@ impl<'a> State<'a> {
 	}
 
 	pub fn update(&mut self) {
-		self.camera_controller.update_camera(&mut self.camera);
+		self.camera_controller.update(&mut self.camera);
+
 		self.camera_info.uniform.update_view_proj(&self.camera);
 		self.queue.write_buffer(
 			&self.camera_info.buffer,
 			0,
 			bytemuck::cast_slice(&[self.camera_info.uniform]),
 		);
+
+		self.spotlight.update();
+		self.spotlight_info
+			.uniform
+			.update(&self.spotlight, &self.camera_controller);
+		self.queue.write_buffer(
+			&self.spotlight_info.buffer,
+			0,
+			bytemuck::cast_slice(&[self.spotlight_info.uniform]),
+		);
 	}
 
 	pub fn render(&mut self) -> Result<(), wgpu::SurfaceError> {
@@ -274,8 +293,9 @@ impl<'a> State<'a> {
 			});
 
 			render_pass.set_pipeline(&self.render_pipeline);
-			render_pass.set_bind_group(0, &self.bind_group, &[]);
+			render_pass.set_bind_group(0, &self.texture_bind_group, &[]);
 			render_pass.set_bind_group(1, &self.camera_info.bind_group, &[]);
+			render_pass.set_bind_group(2, &self.spotlight_info.bind_group, &[]);
 			render_pass.set_vertex_buffer(0, self.vertex_buffer.slice(..));
 			render_pass.set_index_buffer(self.index_buffer.slice(..), wgpu::IndexFormat::Uint16);
 

src/texture.rs

@@ -2,7 +2,7 @@ use image::GenericImageView;
 
 pub struct Texture {
 	pub layout: wgpu::BindGroupLayout,
-	pub group: wgpu::BindGroup,
+	pub bind_group: wgpu::BindGroup,
 }
 
 impl Texture {
@@ -53,8 +53,7 @@ impl Texture {
 			..Default::default()
 		});
 
-		let texture_bind_group_layout =
+		let layout = device.create_bind_group_layout(&wgpu::BindGroupLayoutDescriptor {
-			device.create_bind_group_layout(&wgpu::BindGroupLayoutDescriptor {
 			entries: &[
 				wgpu::BindGroupLayoutEntry {
 					binding: 0,
@@ -77,7 +76,7 @@ impl Texture {
 		});
 
 		let bind_group = device.create_bind_group(&wgpu::BindGroupDescriptor {
-			layout: &texture_bind_group_layout,
+			layout: &layout,
 			entries: &[
 				wgpu::BindGroupEntry {
 					binding: 0,
@@ -91,9 +90,6 @@ impl Texture {
 			label: Some("diffuse_bind_group"),
 		});
 
-		Self {
+		Self { layout, bind_group }
-			layout: texture_bind_group_layout,
-			group: bind_group,
-		}
 	}
 }