From b978091cd433defee65e5ed7db8117484f2b8ec0 Mon Sep 17 00:00:00 2001
From: nullprop <git@nullprop.sh>
Date: Sat, 15 Apr 2023 23:20:26 +0300
Subject: [PATCH] Different depth settings for shadows

---
 src/core/pass.rs    | 14 ++++++++++++--
 src/core/state.rs   |  7 +++++--
 src/core/texture.rs |  6 +++---
 3 files changed, 20 insertions(+), 7 deletions(-)

diff --git a/src/core/pass.rs b/src/core/pass.rs
index 1aa0ca1..c819568 100644
--- a/src/core/pass.rs
+++ b/src/core/pass.rs
@@ -18,6 +18,7 @@ impl RenderPass {
         depth_format: Option<TextureFormat>,
         vertex_layouts: &[VertexBufferLayout],
         label: &str,
+        is_shadow: bool,
     ) -> Self {
         let layout = device.create_pipeline_layout(&wgpu::PipelineLayoutDescriptor {
             label: Some((label.to_owned() + " pipeline Layout").as_str()),
@@ -36,6 +37,7 @@ impl RenderPass {
             vertex_layouts,
             shader,
             label,
+            is_shadow,
         );
 
         Self { pipeline }
@@ -49,6 +51,7 @@ impl RenderPass {
         vertex_layouts: &[wgpu::VertexBufferLayout],
         shader: wgpu::ShaderModuleDescriptor,
         label: &str,
+        is_shadow: bool,
     ) -> wgpu::RenderPipeline {
         let shader = device.create_shader_module(shader);
 
@@ -93,9 +96,16 @@ impl RenderPass {
             depth_stencil: depth_format.map(|format| wgpu::DepthStencilState {
                 format,
                 depth_write_enabled: true,
-                depth_compare: wgpu::CompareFunction::LessEqual,
+                depth_compare: if is_shadow { wgpu::CompareFunction::LessEqual } else { wgpu::CompareFunction::Less },
                 stencil: wgpu::StencilState::default(),
-                bias: wgpu::DepthBiasState::default(),
+                bias: if is_shadow {
+                    wgpu::DepthBiasState {
+                        constant: 2, // bilinear
+                        slope_scale: 2.0,
+                        clamp: 0.0,
+                    }
+                }
+                else { wgpu::DepthBiasState::default() },
             }),
             multisample: wgpu::MultisampleState {
                 count: 1,
diff --git a/src/core/state.rs b/src/core/state.rs
index 952a565..778d689 100644
--- a/src/core/state.rs
+++ b/src/core/state.rs
@@ -138,7 +138,7 @@ impl State {
             &device,
             &config,
             "depth_texture",
-            Some(wgpu::CompareFunction::LessEqual),
+            Some(wgpu::CompareFunction::Less),
             1,
             wgpu::TextureUsages::RENDER_ATTACHMENT,
         );
@@ -373,6 +373,7 @@ impl State {
             Some(Texture::DEPTH_FORMAT),
             &[ModelVertex::desc(), InstanceRaw::desc()],
             "light depth pass",
+            true,
         );
 
         let geometry_pass = RenderPass::new(
@@ -389,6 +390,7 @@ impl State {
             Some(Texture::DEPTH_FORMAT),
             &[ModelVertex::desc(), InstanceRaw::desc()],
             "geometry pass",
+            false,
         );
 
         let light_debug_pass = RenderPass::new(
@@ -400,6 +402,7 @@ impl State {
             Some(Texture::DEPTH_FORMAT),
             &[ModelVertex::desc()],
             "light debug pass",
+            false,
         );
 
         Self {
@@ -446,7 +449,7 @@ impl State {
                 &self.device,
                 &self.config,
                 "depth_texture",
-                Some(wgpu::CompareFunction::LessEqual),
+                Some(wgpu::CompareFunction::Less),
                 1,
                 wgpu::TextureUsages::RENDER_ATTACHMENT,
             );
diff --git a/src/core/texture.rs b/src/core/texture.rs
index 86a040c..c301c5b 100644
--- a/src/core/texture.rs
+++ b/src/core/texture.rs
@@ -37,9 +37,9 @@ impl Texture {
 
         let view = texture.create_view(&wgpu::TextureViewDescriptor::default());
         let sampler = device.create_sampler(&wgpu::SamplerDescriptor {
-            address_mode_u: wgpu::AddressMode::Repeat,
-            address_mode_v: wgpu::AddressMode::Repeat,
-            address_mode_w: wgpu::AddressMode::Repeat,
+            address_mode_u: wgpu::AddressMode::ClampToEdge,
+            address_mode_v: wgpu::AddressMode::ClampToEdge,
+            address_mode_w: wgpu::AddressMode::ClampToEdge,
             mag_filter: wgpu::FilterMode::Linear,
             min_filter: wgpu::FilterMode::Linear,
             mipmap_filter: wgpu::FilterMode::Nearest,