render: implement PCF for point lights, support per-light shadow settings

examples/shadows/src/main.rs

@@ -5,8 +5,11 @@ use lyra_engine::{
         Action, ActionHandler, ActionKind, ActionMapping, ActionMappingId, ActionSource,
         InputActionPlugin, KeyCode, LayoutId, MouseAxis, MouseInput,
     },
-    math::{self, Transform, Vec3},
-    render::light::directional::DirectionalLight,
+    math::{self, Quat, Transform, Vec3},
+    render::{
+        graph::{ShadowCasterSettings, ShadowFilteringMode},
+        light::{directional::DirectionalLight, PointLight},
+    },
     scene::{
         CameraComponent, FreeFlyCamera, FreeFlyCameraPlugin, WorldTransform,
         ACTLBL_LOOK_LEFT_RIGHT, ACTLBL_LOOK_ROLL, ACTLBL_LOOK_UP_DOWN,
@@ -189,19 +192,27 @@ fn setup_scene_plugin(game: &mut Game) {
             light_tran,
         ));
 
-        /* world.spawn((
-            //cube_mesh.clone(),
+        world.spawn((
+            cube_mesh.clone(),
             PointLight {
                 enabled: true,
                 color: Vec3::new(0.133, 0.098, 0.91),
                 intensity: 2.0,
-                range: 9.0,
+                range: 10.0,
                 ..Default::default()
             },
-            Transform::from_xyz(5.0, -2.5, -3.3),
+            ShadowCasterSettings {
+                filtering_mode: ShadowFilteringMode::Pcf,
+                ..Default::default()
+            },
+            Transform::new(
+                Vec3::new(4.0 - 1.43, -13.0, 1.53),
+                Quat::IDENTITY,
+                Vec3::new(0.5, 0.5, 0.5),
+            ),
         ));
 
-        world.spawn((
+        /* world.spawn((
             //cube_mesh.clone(),
             PointLight {
                 enabled: true,
@@ -216,8 +227,14 @@ fn setup_scene_plugin(game: &mut Game) {
 
     let mut camera = CameraComponent::new_3d();
     //camera.transform.translation += math::Vec3::new(0.0, 2.0, 10.5);
-    camera.transform.translation = math::Vec3::new(-3.0, -8.0, -3.0);
+    /* camera.transform.translation = math::Vec3::new(-3.0, -8.0, -3.0);
     camera.transform.rotate_x(math::Angle::Degrees(-27.0));
-    camera.transform.rotate_y(math::Angle::Degrees(-55.0));
+    camera.transform.rotate_y(math::Angle::Degrees(-55.0)); */
+
+    camera.transform.translation = math::Vec3::new(15.0, -8.0, 1.0);
+    camera.transform.rotate_x(math::Angle::Degrees(-27.0));
+    //camera.transform.rotate_y(math::Angle::Degrees(-90.0));
+    camera.transform.rotate_y(math::Angle::Degrees(90.0));
+
     world.spawn((camera, FreeFlyCamera::default()));
 }

lyra-game/src/render/graph/passes/meshes.rs

@@ -135,6 +135,11 @@ impl Node for MeshPass {
                 .expect("missing ShadowMapsPassSlots::PcfPoissonDiscBuffer")
                 .as_buffer()
                 .unwrap();
+            let pcf_poisson_disc_3d = graph
+                .slot_value(ShadowMapsPassSlots::PcfPoissonDiscBuffer3d)
+                .expect("missing ShadowMapsPassSlots::PcfPoissonDiscBuffer3d")
+                .as_buffer()
+                .unwrap();
             let pcss_poisson_disc = graph
                 .slot_value(ShadowMapsPassSlots::PcssPoissonDiscBuffer)
                 .expect("missing ShadowMapsPassSlots::PcssPoissonDiscBuffer")
@@ -206,6 +211,16 @@ impl Node for MeshPass {
                         },
                         count: None,
                     },
+                    wgpu::BindGroupLayoutEntry {
+                        binding: 7,
+                        visibility: wgpu::ShaderStages::VERTEX_FRAGMENT,
+                        ty: wgpu::BindingType::Buffer {
+                            ty: wgpu::BufferBindingType::Storage { read_only: true },
+                            has_dynamic_offset: false,
+                            min_binding_size: None,
+                        },
+                        count: None,
+                    },
                 ],
             });
 
@@ -251,6 +266,14 @@ impl Node for MeshPass {
                     },
                     wgpu::BindGroupEntry {
                         binding: 6,
+                        resource: wgpu::BindingResource::Buffer(wgpu::BufferBinding {
+                            buffer: pcf_poisson_disc_3d,
+                            offset: 0,
+                            size: None,
+                        }),
+                    },
+                    wgpu::BindGroupEntry {
+                        binding: 7,
                         resource: wgpu::BindingResource::Buffer(wgpu::BufferBinding {
                             buffer: pcss_poisson_disc,
                             offset: 0,

lyra-game/src/render/graph/passes/shadows.rs

@@ -1,8 +1,11 @@
 use std::{
-    collections::VecDeque, mem, rc::Rc, sync::{Arc, RwLock, RwLockReadGuard, RwLockWriteGuard}
+    collections::VecDeque,
+    mem,
+    rc::Rc,
+    sync::{Arc, RwLock, RwLockReadGuard, RwLockWriteGuard},
 };
 
-use fast_poisson::Poisson2D;
+use fast_poisson::{Poisson2D, Poisson3D};
 use glam::Vec2;
 use itertools::Itertools;
 use lyra_ecs::{
@@ -26,7 +29,7 @@ use crate::render::{
 
 use super::{MeshBufferStorage, RenderAssets, RenderMeshes};
 
-const SHADOW_SIZE: glam::UVec2 = glam::uvec2(4096, 4096);
+const SHADOW_SIZE: glam::UVec2 = glam::uvec2(1024, 1024);
 
 #[derive(Debug, Clone, Hash, PartialEq, RenderGraphLabel)]
 pub enum ShadowMapsPassSlots {
@@ -38,6 +41,7 @@ pub enum ShadowMapsPassSlots {
     ShadowLightUniformsBuffer,
     ShadowSettingsUniform,
     PcfPoissonDiscBuffer,
+    PcfPoissonDiscBuffer3d,
     PcssPoissonDiscBuffer,
 }
 
@@ -101,7 +105,7 @@ impl ShadowMapsPass {
             device,
             wgpu::TextureFormat::Depth32Float,
             wgpu::TextureUsages::RENDER_ATTACHMENT | wgpu::TextureUsages::TEXTURE_BINDING,
-            SHADOW_SIZE * 2,
+            SHADOW_SIZE * 8,
         );
 
         let atlas_size_buffer = device.create_buffer_init(&wgpu::util::BufferInitDescriptor {
@@ -182,23 +186,49 @@ impl ShadowMapsPass {
         light_type: LightType,
         entity: Entity,
         light_pos: Transform,
-        far_plane: f32,
+        are_settings_custom: bool,
+        shadow_settings: ShadowCasterSettings,
     ) -> LightDepthMap {
-        const NEAR_PLANE: f32 = 0.1;
-        const FAR_PLANE: f32 = 45.0;
-
         let mut atlas = self.atlas.get_mut();
 
+        let u = ShadowSettingsUniform::new(
+            shadow_settings.filtering_mode,
+            shadow_settings.pcf_samples_num,
+            shadow_settings.pcss_blocker_search_samples,
+        );
+
+        let has_shadow_settings = if are_settings_custom {
+            1
+        } else { 0 };
+        /* let (has_shadow_settings, pcf_samples_num, pcss_samples_num) = if are_settings_custom {
+            
+            (1, u.pcf_samples_num, u.pcss_blocker_search_samples)
+        } else {
+            (0, , 0)
+        }; */
+
+        /* shadow_settings.map(|ss| {
+            let u = ShadowSettingsUniform::new(ss.filtering_mode, ss.pcf_samples_num, ss.pcss_blocker_search_samples);
+            (1, u.pcf_samples_num, u.pcss_blocker_search_samples)
+        }).unwrap_or((0, 0, 0)); */
+
         let (start_atlas_idx, uniform_indices) = match light_type {
             LightType::Directional => {
+                let directional_size = SHADOW_SIZE * 4;
                 // directional lights require a single map, so allocate that in the atlas.
                 let atlas_index = atlas
-                    .pack(SHADOW_SIZE.x as _, SHADOW_SIZE.y as _)
+                    .pack(directional_size.x as _, directional_size.y as _)
                     .expect("failed to pack new shadow map into texture atlas");
                 let atlas_frame = atlas.texture_frame(atlas_index).expect("Frame missing");
 
-                let projection =
-                    glam::Mat4::orthographic_rh(-10.0, 10.0, -10.0, 10.0, NEAR_PLANE, FAR_PLANE);
+                let projection = glam::Mat4::orthographic_rh(
+                    -10.0,
+                    10.0,
+                    -10.0,
+                    10.0,
+                    shadow_settings.near_plane,
+                    shadow_settings.far_plane,
+                );
 
                 // honestly no clue why this works, but I got it from here and the results are good
                 // https://github.com/asylum2010/Asylum_Tutorials/blob/423e5edfaee7b5ea450a450e65f2eabf641b2482/ShaderTutors/43_ShadowMapFiltering/main.cpp#L323
@@ -218,12 +248,15 @@ impl ShadowMapsPass {
                 let u = LightShadowUniform {
                     space_mat: light_proj,
                     atlas_frame,
-                    near_plane: NEAR_PLANE,
-                    far_plane,
+                    near_plane: shadow_settings.near_plane,
+                    far_plane: shadow_settings.far_plane,
                     light_size_uv,
                     _padding1: 0,
                     light_pos: light_pos.translation,
-                    _padding2: 0,
+                    has_shadow_settings,
+                    pcf_samples_num: u.pcf_samples_num,
+                    pcss_blocker_search_samples: u.pcss_blocker_search_samples,
+                    _padding2: [0; 2],
                 };
 
                 let uniform_index = self.light_uniforms_buffer.insert(queue, &u);
@@ -237,8 +270,8 @@ impl ShadowMapsPass {
                 let projection = glam::Mat4::perspective_rh(
                     Angle::Degrees(90.0).to_radians(),
                     aspect,
-                    NEAR_PLANE,
-                    far_plane,
+                    shadow_settings.near_plane,
+                    shadow_settings.far_plane,
                 );
 
                 let light_trans = light_pos.translation;
@@ -307,12 +340,15 @@ impl ShadowMapsPass {
                         &LightShadowUniform {
                             space_mat: views[i],
                             atlas_frame: frames[i],
-                            near_plane: NEAR_PLANE,
-                            far_plane,
+                            near_plane: shadow_settings.near_plane,
+                            far_plane: shadow_settings.far_plane,
                             light_size_uv: 0.0,
                             _padding1: 0,
                             light_pos: light_trans,
-                            _padding2: 0,
+                            has_shadow_settings,
+                            pcf_samples_num: u.pcf_samples_num,
+                            pcss_blocker_search_samples: u.pcss_blocker_search_samples,
+                            _padding2: [0; 2],
                         },
                     );
                     indices[i] = uniform_i;
@@ -345,31 +381,66 @@ impl ShadowMapsPass {
     }
 
     /// Create the gpu buffer for a poisson disc
-    fn create_poisson_disc_buffer(&self, device: &wgpu::Device, label: &str, num_samples: u32) -> wgpu::Buffer {
+    fn create_poisson_disc_buffer(
+        &self,
+        device: &wgpu::Device,
+        label: &str,
+        dimension: u32,
+        num_samples: u32,
+    ) -> wgpu::Buffer {
+        debug_assert!(
+            dimension == 2 || dimension == 3,
+            "unknown dimension {dimension}, expected 2 (2d) or 3 (3d)"
+        );
+
         device.create_buffer(&wgpu::BufferDescriptor {
             label: Some(label),
-            size: mem::size_of::<glam::Vec2>() as u64 * (num_samples * 2) as u64,
+            size: mem::size_of::<glam::Vec2>() as u64 * (num_samples * dimension) as u64,
             usage: wgpu::BufferUsages::STORAGE | wgpu::BufferUsages::COPY_DST,
             mapped_at_creation: false,
         })
     }
 
     /// Generate and write a Poisson disc to `buffer` with `num_pcf_samples.pow(2)` amount of points.
-    fn write_poisson_disc(&self, queue: &wgpu::Queue, buffer: &wgpu::Buffer, num_samples: u32) {
-        let num_floats = num_samples * 2; // points are vec2f
+    fn write_poisson_disc(
+        &self,
+        queue: &wgpu::Queue,
+        buffer: &wgpu::Buffer,
+        dimension: u32,
+        num_samples: u32,
+    ) {
+        debug_assert!(
+            dimension == 2 || dimension == 3,
+            "unknown dimension {dimension}, expected 2 (2d) or 3 (3d)"
+        );
+
+        let num_floats = num_samples * dimension; // points are vec2f
         let min_dist = (num_floats as f32).sqrt() / num_floats as f32;
         let mut points = vec![];
 
         // use a while loop to ensure that the correct number of floats is created
         while points.len() < num_floats as usize {
-            let poisson = Poisson2D::new()
-                .with_dimensions([1.0, 1.0], min_dist)
-                .with_samples(num_samples);
+            if dimension == 2 {
+                let poisson = Poisson2D::new()
+                    .with_dimensions([1.0, 1.0], min_dist)
+                    .with_samples(num_samples);
 
-            points = poisson.iter().flatten()
-                .map(|p| p * 2.0 - 1.0)
-                .collect_vec();
+                points = poisson
+                    .iter()
+                    .flatten()
+                    .map(|p| p * 2.0 - 1.0)
+                    .collect_vec();
+            } else if dimension == 3 {
+                let poisson = Poisson3D::new()
+                    .with_dimensions([1.0, 1.0, 1.0], min_dist)
+                    .with_samples(num_samples);
 
+                points = poisson
+                    .iter()
+                    .flatten()
+                    .map(|p| p * 2.0 - 1.0)
+                    .collect_vec();
+            }
         }
         points.truncate(num_floats as _);
 
@@ -441,7 +512,25 @@ impl Node for ShadowMapsPass {
             ShadowMapsPassSlots::PcfPoissonDiscBuffer,
             SlotAttribute::Output,
             Some(SlotValue::Buffer(Arc::new(
-                self.create_poisson_disc_buffer(device, "buffer_poisson_disc_pcf", PCF_SAMPLES_NUM_MAX),
+                self.create_poisson_disc_buffer(
+                    device,
+                    "buffer_poisson_disc_pcf",
+                    2,
+                    PCF_SAMPLES_NUM_MAX,
+                ),
+            ))),
+        );
+
+        node.add_buffer_slot(
+            ShadowMapsPassSlots::PcfPoissonDiscBuffer3d,
+            SlotAttribute::Output,
+            Some(SlotValue::Buffer(Arc::new(
+                self.create_poisson_disc_buffer(
+                    device,
+                    "buffer_poisson_disc_pcf_3d",
+                    3,
+                    PCF_SAMPLES_NUM_MAX,
+                ),
             ))),
         );
 
@@ -449,7 +538,12 @@ impl Node for ShadowMapsPass {
             ShadowMapsPassSlots::PcssPoissonDiscBuffer,
             SlotAttribute::Output,
             Some(SlotValue::Buffer(Arc::new(
-                self.create_poisson_disc_buffer(device, "buffer_poisson_disc_pcss", PCSS_SAMPLES_NUM_MAX),
+                self.create_poisson_disc_buffer(
+                    device,
+                    "buffer_poisson_disc_pcss",
+                    2,
+                    PCSS_SAMPLES_NUM_MAX,
+                ),
             ))),
         );
 
@@ -462,28 +556,43 @@ impl Node for ShadowMapsPass {
         world: &mut lyra_ecs::World,
         context: &mut crate::render::graph::RenderGraphContext,
     ) {
-        world.add_resource_default_if_absent::<ShadowSettings>();
-        if world.has_resource_changed::<ShadowSettings>() {
+        world.add_resource_default_if_absent::<ShadowCasterSettings>();
+        if world.has_resource_changed::<ShadowCasterSettings>() {
             debug!("Detected change in ShadowSettings, recreating poisson disks");
 
-            let settings = world.get_resource::<ShadowSettings>();
+            let settings = world.get_resource::<ShadowCasterSettings>();
             // convert to uniform now since the from impl limits to max values
             let uniform = ShadowSettingsUniform::from(*settings);
 
-            let buffer = graph.slot_value(ShadowMapsPassSlots::PcfPoissonDiscBuffer)
-                .unwrap().as_buffer().unwrap();
-            self.write_poisson_disc(&context.queue, &buffer, uniform.pcf_samples_num);
+            let buffer = graph
+                .slot_value(ShadowMapsPassSlots::PcfPoissonDiscBuffer)
+                .unwrap()
+                .as_buffer()
+                .unwrap();
+            self.write_poisson_disc(&context.queue, &buffer, 2, uniform.pcf_samples_num);
 
-            let buffer = graph.slot_value(ShadowMapsPassSlots::PcssPoissonDiscBuffer)
-                .unwrap().as_buffer().unwrap();
-            self.write_poisson_disc(&context.queue, &buffer, uniform.pcss_blocker_search_samples);
+            let buffer = graph
+                .slot_value(ShadowMapsPassSlots::PcfPoissonDiscBuffer3d)
+                .unwrap()
+                .as_buffer()
+                .unwrap();
+            self.write_poisson_disc(&context.queue, &buffer, 3, uniform.pcf_samples_num);
 
-            context.queue_buffer_write_with(
-                ShadowMapsPassSlots::ShadowSettingsUniform,
-                0,
-                uniform,
+            let buffer = graph
+                .slot_value(ShadowMapsPassSlots::PcssPoissonDiscBuffer)
+                .unwrap()
+                .as_buffer()
+                .unwrap();
+            self.write_poisson_disc(
+                &context.queue,
+                &buffer,
+                2,
+                uniform.pcss_blocker_search_samples,
             );
+
+            context.queue_buffer_write_with(ShadowMapsPassSlots::ShadowSettingsUniform, 0, uniform);
         }
+        let settings = *world.get_resource::<ShadowCasterSettings>();
 
         self.render_meshes = world.try_get_resource_data::<RenderMeshes>();
         self.transform_buffers = world.try_get_resource_data::<TransformBuffers>();
@@ -494,23 +603,48 @@ impl Node for ShadowMapsPass {
         // use a queue for storing atlas ids to add to entities after the entities are iterated
         let mut index_components_queue = VecDeque::new();
 
-        for (entity, pos, _) in world.view_iter::<(Entities, &Transform, Has<DirectionalLight>)>() {
+        for (entity, pos, shadow_settings, _) in world.view_iter::<(
+            Entities,
+            &Transform,
+            Option<&ShadowCasterSettings>,
+            Has<DirectionalLight>,
+        )>() {
             if !self.depth_maps.contains_key(&entity) {
+                let (custom_settings, shadow_settings) = shadow_settings
+                    .map(|ss| (true, ss.clone()))
+                    .unwrap_or((false, settings));
+
                 let atlas_index = self.create_depth_map(
                     &context.queue,
                     LightType::Directional,
                     entity,
                     *pos,
-                    45.0,
+                    custom_settings,
+                    shadow_settings,
                 );
                 index_components_queue.push_back((entity, atlas_index));
             }
         }
 
-        for (entity, pos, _) in world.view_iter::<(Entities, &Transform, Has<PointLight>)>() {
+        for (entity, pos, shadow_settings, _) in world.view_iter::<(
+            Entities,
+            &Transform,
+            Option<&ShadowCasterSettings>,
+            Has<PointLight>,
+        )>() {
             if !self.depth_maps.contains_key(&entity) {
-                let atlas_index =
-                    self.create_depth_map(&context.queue, LightType::Point, entity, *pos, 30.0);
+                let (custom_settings, shadow_settings) = shadow_settings
+                    .map(|ss| (true, ss.clone()))
+                    .unwrap_or((false, settings));
+
+                let atlas_index = self.create_depth_map(
+                    &context.queue,
+                    LightType::Point,
+                    entity,
+                    *pos,
+                    custom_settings,
+                    shadow_settings,
+                );
                 index_components_queue.push_back((entity, atlas_index));
             }
         }
@@ -736,6 +870,38 @@ fn light_shadow_pass_impl<'a>(
     }
 }
 
+/// Shadow casting settings for a light caster.
+///
+/// Put this on an entity with a light source to override the global shadow
+/// settings, the [`ShadowSettings`] resource.
+#[derive(Debug, Copy, Clone, Component)]
+pub struct ShadowCasterSettings {
+    pub filtering_mode: ShadowFilteringMode,
+    /// How many PCF filtering samples are used per dimension.
+    ///
+    /// A value of 25 is common, this is maxed to 128.
+    pub pcf_samples_num: u32,
+    /// How many samples are used for the PCSS blocker search step.
+    ///
+    /// Multiple samples are required to avoid holes int he penumbra due to missing blockers.
+    /// A value of 25 is common, this is maxed to 128.
+    pub pcss_blocker_search_samples: u32,
+    pub near_plane: f32,
+    pub far_plane: f32,
+}
+
+impl Default for ShadowCasterSettings {
+    fn default() -> Self {
+        Self {
+            filtering_mode: ShadowFilteringMode::default(),
+            pcf_samples_num: 25,
+            pcss_blocker_search_samples: 25,
+            near_plane: 0.1,
+            far_plane: 45.0,
+        }
+    }
+}
+
 #[repr(C)]
 #[derive(Debug, Copy, Clone, bytemuck::Pod, bytemuck::Zeroable)]
 pub struct LightShadowUniform {
@@ -747,7 +913,11 @@ pub struct LightShadowUniform {
     light_size_uv: f32,
     _padding1: u32,
     light_pos: glam::Vec3,
-    _padding2: u32,
+    /// Boolean casted as integer
+    has_shadow_settings: u32,
+    pcf_samples_num: u32,
+    pcss_blocker_search_samples: u32,
+    _padding2: [u32; 2],
 }
 
 /// A component that stores the ID of a shadow map in the shadow map atlas for the entities.
@@ -794,7 +964,7 @@ pub enum ShadowFilteringMode {
     Pcss,
 }
 
-#[derive(Debug, Copy, Clone)]
+/* #[derive(Debug, Copy, Clone)]
 pub struct ShadowSettings {
     pub filtering_mode: ShadowFilteringMode,
     /// How many PCF filtering samples are used per dimension.
@@ -816,7 +986,7 @@ impl Default for ShadowSettings {
             pcss_blocker_search_samples: 25,
         }
     }
-}
+} */
 
 const PCF_SAMPLES_NUM_MAX: u32 = 128;
 const PCSS_SAMPLES_NUM_MAX: u32 = 128;
@@ -834,12 +1004,27 @@ struct ShadowSettingsUniform {
     pcss_blocker_search_samples: u32,
 }
 
-impl From<ShadowSettings> for ShadowSettingsUniform {
-    fn from(value: ShadowSettings) -> Self {
-        let raw_pcf_samples = value.pcf_samples_num.min(PCF_SAMPLES_NUM_MAX);
-        let raw_pcss_samples = value.pcss_blocker_search_samples.min(PCSS_SAMPLES_NUM_MAX);
+impl From<ShadowCasterSettings> for ShadowSettingsUniform {
+    fn from(value: ShadowCasterSettings) -> Self {
+        Self::new(
+            value.filtering_mode,
+            value.pcf_samples_num,
+            value.pcss_blocker_search_samples,
+        )
+    }
+}
 
-        let (pcf_samples, pcss_samples) = match value.filtering_mode {
+impl ShadowSettingsUniform {
+    /// Create a new shadow settings uniform.
+    pub fn new(
+        filter_mode: ShadowFilteringMode,
+        pcf_samples_num: u32,
+        pcss_blocker_search_samples: u32,
+    ) -> Self {
+        let raw_pcf_samples = pcf_samples_num.min(PCF_SAMPLES_NUM_MAX);
+        let raw_pcss_samples = pcss_blocker_search_samples.min(PCSS_SAMPLES_NUM_MAX);
+
+        let (pcf_samples, pcss_samples) = match filter_mode {
             ShadowFilteringMode::None => (0, 0),
             ShadowFilteringMode::Pcf2x2 => (2, 0),
             ShadowFilteringMode::Pcf => (raw_pcf_samples, 0),

lyra-game/src/render/shaders/base.wgsl

@@ -119,6 +119,10 @@ struct LightShadowMapUniform {
     far_plane: f32,
     light_size_uv: f32,
     light_pos: vec3<f32>,
+    /// boolean casted as u32
+    has_shadow_settings: u32,
+    pcf_samples_num: u32,
+    pcss_blocker_search_samples: u32,
 }
 
 struct ShadowSettingsUniform {
@@ -144,6 +148,8 @@ var<storage, read> u_light_shadow: array<LightShadowMapUniform>;
 @group(5) @binding(5)
 var<storage, read> u_pcf_poisson_disc: array<vec2<f32>>;
 @group(5) @binding(6)
+var<storage, read> u_pcf_poisson_disc_3d: array<vec3<f32>>;
+@group(5) @binding(7)
 var<storage, read> u_pcss_poisson_disc: array<vec2<f32>>;
 
 @fragment
@@ -180,7 +186,7 @@ fn fs_main(in: VertexOutput) -> @location(0) vec4<f32> {
             let shadow = calc_shadow_dir_light(in.world_normal, light_dir, frag_pos_light_space, atlas_dimensions, shadow_u);
             light_res += blinn_phong_dir_light(in.world_position, in.world_normal, light, u_material, specular_color, shadow);
         } else if (light.light_ty == LIGHT_TY_POINT) {
-            let shadow = calc_shadow_point(in.world_position, in.world_normal, light_dir, light, atlas_dimensions);
+            let shadow = calc_shadow_point_light(in.world_position, in.world_normal, light_dir, light, atlas_dimensions);
             light_res += blinn_phong_point_light(in.world_position, in.world_normal, light, u_material, specular_color, shadow);
         } else if (light.light_ty == LIGHT_TY_SPOT) {
             light_res += blinn_phong_spot_light(in.world_position, in.world_normal, light, u_material, specular_color);
@@ -249,6 +255,16 @@ fn coords_to_cube_atlas(tex_coord: vec3<f32>) -> vec3<f32> {
     return vec3<f32>(res, f32(cube_idx));
 }
 
+/// Get shadow settings for a light.
+/// Returns x as `pcf_samples_num` and y as `pcss_blocker_search_samples`.
+fn get_shadow_settings(shadow_u: LightShadowMapUniform) -> vec2<u32> {
+    if shadow_u.has_shadow_settings == 1u {
+        return vec2<u32>(shadow_u.pcf_samples_num, shadow_u.pcss_blocker_search_samples);
+    } else {
+        return vec2<u32>(u_shadow_settings.pcf_samples_num, u_shadow_settings.pcss_blocker_search_samples);
+    }
+}
+
 fn calc_shadow_dir_light(normal: vec3<f32>, light_dir: vec3<f32>, frag_pos_light_space: vec4<f32>, atlas_dimensions: vec2<i32>, shadow_u: LightShadowMapUniform) -> f32 {
     var proj_coords = frag_pos_light_space.xyz / frag_pos_light_space.w;
     // for some reason the y component is flipped after transforming
@@ -261,21 +277,28 @@ fn calc_shadow_dir_light(normal: vec3<f32>, light_dir: vec3<f32>, frag_pos_light
     let bias = 0.005;//max(0.05 * (1.0 - dot(normal, light_dir)), 0.005);  
     let current_depth = proj_coords.z - bias;
 
+    // get settings
+    let settings = get_shadow_settings(shadow_u);
+    let pcf_samples_num = settings.x;
+    let pcss_blocker_search_samples = settings.y;
+
     var shadow = 0.0;
-    if u_shadow_settings.pcf_samples_num > 0u && u_shadow_settings.pcss_blocker_search_samples > 0u {
+    // hardware 2x2 PCF via camparison sampler
+    if pcf_samples_num == 2u {
+        let region_coords = to_atlas_frame_coords(shadow_u, xy_remapped);
+        shadow = textureSampleCompareLevel(t_shadow_maps_atlas, s_shadow_maps_atlas_compare, region_coords, current_depth);
+    }
+    // PCSS
+    else if pcf_samples_num > 0u && pcss_blocker_search_samples > 0u {
         shadow = pcss_dir_light(xy_remapped, current_depth, shadow_u);
     }
-    // hardware 2x2 PCF via camparison sampler
-    else if u_shadow_settings.pcf_samples_num == 2u {
-        let region_coords = to_atlas_frame_coords(shadow_u, xy_remapped);
-        shadow = textureSampleCompare(t_shadow_maps_atlas, s_shadow_maps_atlas_compare, region_coords, current_depth);
-    } else if u_shadow_settings.pcf_samples_num > 0u {
-        let atlas_dimensions = textureDimensions(t_shadow_maps_atlas);
-        // TODO: should texel size be using the entire atlas dimensions, or just the frame?
-        let texel_size = 1.0 / f32(atlas_dimensions.x); // f32(shadow_u.atlas_frame.width)
-
+    // only PCF
+    else if pcf_samples_num > 0u {
+        let texel_size = 1.0 / f32(shadow_u.atlas_frame.width);
         shadow = pcf_dir_light(xy_remapped, current_depth, shadow_u, texel_size);
-    } else { // pcf_samples_num == 0
+    }
+    // no filtering
+    else {
         let region_coords = to_atlas_frame_coords(shadow_u, xy_remapped);
         let closest_depth = textureSampleLevel(t_shadow_maps_atlas, s_shadow_maps_atlas, region_coords, 0.0);
         shadow = select(1.0, 0.0, current_depth > closest_depth);
@@ -304,14 +327,19 @@ fn to_atlas_frame_coords(shadow_u: LightShadowMapUniform, coords: vec2<f32>) ->
     let atlas_dimensions = textureDimensions(t_shadow_maps_atlas);
     
     // get the rect of the frame as a vec4
-    var region_rect = vec4<f32>(f32(shadow_u.atlas_frame.x), f32(shadow_u.atlas_frame.y), f32(shadow_u.atlas_frame.width), f32(shadow_u.atlas_frame.height));
+    var region_rect = vec4<f32>(f32(shadow_u.atlas_frame.x), f32(shadow_u.atlas_frame.y),
+        f32(shadow_u.atlas_frame.width), f32(shadow_u.atlas_frame.height));
     // put the frame rect in atlas UV space
     region_rect /= f32(atlas_dimensions.x);
 
+    // calculate a relatively tiny offset to avoid getting the end of the frame and causing
+    // linear or nearest filtering to bleed to the adjacent frame.
+    let texel_size = (1.0 / f32(shadow_u.atlas_frame.x)) * 4.0;
+    
     // lerp input coords 
     let region_coords = vec2<f32>(
-        mix(region_rect.x, region_rect.x + region_rect.z, coords.x),
-        mix(region_rect.y, region_rect.y + region_rect.w, coords.y)
+        mix(region_rect.x + texel_size, region_rect.x + region_rect.z - texel_size, coords.x),
+        mix(region_rect.y + texel_size, region_rect.y + region_rect.w - texel_size, coords.y)
     );
     
     return region_coords;
@@ -372,45 +400,96 @@ fn pcf_dir_light(tex_coords: vec2<f32>, test_depth: f32, shadow_u: LightShadowMa
     return saturate(shadow);
 }
 
-fn calc_shadow_point(world_pos: vec3<f32>, world_normal: vec3<f32>, light_dir: vec3<f32>, light: Light, atlas_dimensions: vec2<i32>) -> f32 {
+fn calc_shadow_point_light(world_pos: vec3<f32>, world_normal: vec3<f32>, light_dir: vec3<f32>, light: Light, atlas_dimensions: vec2<i32>) -> f32 {
     var frag_to_light = world_pos - light.position;
     let temp = coords_to_cube_atlas(normalize(frag_to_light));
     var coords_2d = temp.xy;
     let cube_idx = i32(temp.z);
 
-    /// if an unknown cube side was returned, something is broken
-    /*if cube_idx == 0 {
-        return 0.0;
-    }*/
-
     var indices = light.light_shadow_uniform_index;
     let i = indices[cube_idx - 1];
     let u: LightShadowMapUniform = u_light_shadow[i];
 
-    // get the atlas frame in [0; 1] in the atlas texture
-    // z is width, w is height
-    var region_coords = vec4<f32>(f32(u.atlas_frame.x), f32(u.atlas_frame.y), f32(u.atlas_frame.width), f32(u.atlas_frame.height));
-    region_coords /= f32(atlas_dimensions.x);
+    let uniforms = array<LightShadowMapUniform, 6>(
+        u_light_shadow[indices[0]],
+        u_light_shadow[indices[1]],
+        u_light_shadow[indices[2]],
+        u_light_shadow[indices[3]],
+        u_light_shadow[indices[4]],
+        u_light_shadow[indices[5]]
+    );
     
-    // simulate `ClampToBorder`, not creating shadows past the shadow map regions
-    /*if (coords_2d.x >= 1.0 || coords_2d.y >= 1.0) {
-        return 0.0;
-    }*/
-
-    // get the coords inside of the region
-    coords_2d.x = mix(region_coords.x, region_coords.x + region_coords.z, coords_2d.x);
-    coords_2d.y = mix(region_coords.y, region_coords.y + region_coords.w, coords_2d.y);
-
-    // use a bias to avoid shadow acne
-    let bias = max(0.05 * (1.0 - dot(world_normal, light_dir)), 0.005);
-    var current_depth = length(frag_to_light) - bias;
+    var current_depth = length(frag_to_light);
     current_depth /= u.far_plane;
+    current_depth -= 0.005; // TODO: find a better way to calculate bias
 
-    var shadow = textureSampleCompare(t_shadow_maps_atlas, s_shadow_maps_atlas_compare, coords_2d, current_depth);
+    // get settings
+    let settings = get_shadow_settings(u);
+    let pcf_samples_num = settings.x;
+    let pcss_blocker_search_samples = settings.y;
+
+    var shadow = 0.0;
+    // hardware 2x2 PCF via camparison sampler
+    if pcf_samples_num == 2u {
+        let region_coords = to_atlas_frame_coords(u, coords_2d);
+        shadow = textureSampleCompareLevel(t_shadow_maps_atlas, s_shadow_maps_atlas_compare, region_coords, current_depth);
+    }
+    // PCSS
+    else if pcf_samples_num > 0u && pcss_blocker_search_samples > 0u {
+        shadow = pcss_dir_light(coords_2d, current_depth, u);
+    }
+    // only PCF
+    else if pcf_samples_num > 0u {
+        let texel_size = 1.0 / f32(u.atlas_frame.width);
+        shadow = pcf_point_light(frag_to_light, current_depth, uniforms, pcf_samples_num, 0.007);
+        //shadow = pcf_point_light(coords_2d, current_depth, u, pcf_samples_num, texel_size);
+    }
+    // no filtering
+    else {
+        let region_coords = to_atlas_frame_coords(u, coords_2d);
+        let closest_depth = textureSampleLevel(t_shadow_maps_atlas, s_shadow_maps_atlas, region_coords, 0.0);
+        shadow = select(1.0, 0.0, current_depth > closest_depth);
+    }
 
     return shadow;
 }
 
+/// Calculate the shadow coefficient using PCF of a directional light
+fn pcf_point_light(tex_coords: vec3<f32>, test_depth: f32, shadow_us: array<LightShadowMapUniform, 6>, samples_num: u32, uv_radius: f32) -> f32 {
+    var shadow_unis = shadow_us;
+    
+    var shadow = 0.0;
+    for (var i = 0; i < i32(samples_num); i++) {
+        var temp = coords_to_cube_atlas(tex_coords);
+        var coords_2d = temp.xy;
+        var cube_idx = i32(temp.z);
+        var shadow_u = shadow_unis[cube_idx - 1];
+
+        coords_2d += u_pcf_poisson_disc[i] * uv_radius;
+
+        let new_coords = to_atlas_frame_coords(shadow_u, coords_2d);
+        shadow += textureSampleCompare(t_shadow_maps_atlas, s_shadow_maps_atlas_compare, new_coords, test_depth);
+    }
+    shadow /= f32(samples_num);
+
+    // clamp shadow to [0; 1]
+    return saturate(shadow);
+}
+
+/*fn pcf_point_light(tex_coords: vec2<f32>, test_depth: f32, shadow_u: LightShadowMapUniform, samples_num: u32, uv_radius: f32) -> f32 {
+    var shadow = 0.0;
+    for (var i = 0; i < i32(samples_num); i++) {
+        let offset = tex_coords + u_pcf_poisson_disc[i] * uv_radius;
+        let new_coords = to_atlas_frame_coords(shadow_u, offset);
+        
+        shadow += textureSampleCompare(t_shadow_maps_atlas, s_shadow_maps_atlas_compare, new_coords, test_depth);
+    }
+    shadow /= f32(samples_num);
+
+    // clamp shadow to [0; 1]
+    return saturate(shadow);
+}*/
+
 fn debug_grid(in: VertexOutput) -> vec4<f32> {
     let tile_index_float: vec2<f32> = in.clip_position.xy / 16.0;
     let tile_index = vec2<u32>(floor(tile_index_float));
@@ -485,7 +564,8 @@ fn blinn_phong_point_light(world_pos: vec3<f32>, world_norm: vec3<f32>, point_li
     diffuse_color *= attenuation;
     specular_color *= attenuation;
 
-    return (ambient_color + (1.0 - shadow) * (diffuse_color + specular_color)) * point_light.intensity;
+    //return (ambient_color + shadow * (diffuse_color + specular_color)) * point_light.intensity;
+    return (shadow * (ambient_color + diffuse_color + specular_color)) * point_light.intensity;
 }
 
 fn blinn_phong_spot_light(world_pos: vec3<f32>, world_norm: vec3<f32>, spot_light: Light, material: Material, specular_factor: vec3<f32>) -> vec3<f32> {

lyra-game/src/render/shaders/shadows.wgsl

@@ -13,7 +13,12 @@ struct LightShadowMapUniform {
     atlas_frame: TextureAtlasFrame,
     near_plane: f32,
     far_plane: f32,
+    light_size_uv: f32,
     light_pos: vec3<f32>,
+    /// boolean casted as u32
+    has_shadow_settings: u32,
+    pcf_samples_num: u32,
+    pcss_blocker_search_samples: u32,
 }
 
 @group(0) @binding(0)