From a0e39796bf352f184114653a5283ba129febcacf Mon Sep 17 00:00:00 2001
From: Simon Gellis <simongellis@gmail.com>
Date: Sun, 3 Nov 2024 13:49:10 -0500
Subject: [PATCH] Actually do anaglyph

---
 Cargo.lock        | 15 +++++++++++++++
 Cargo.toml        |  1 +
 src/anaglyph.wgsl | 10 ++++++++--
 src/app.rs        | 31 +++++++++++++++++++++++++++++++
 4 files changed, 55 insertions(+), 2 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 023dbe0..7a98704 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -220,6 +220,20 @@ name = "bytemuck"
 version = "1.19.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8334215b81e418a0a7bdb8ef0849474f40bb10c8b71f1c4ed315cff49f32494d"
+dependencies = [
+ "bytemuck_derive",
+]
+
+[[package]]
+name = "bytemuck_derive"
+version = "1.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bcfcc3cd946cb52f0bbfdbbcfa2f4e24f75ebb6c0e1002f7c25904fada18b9ec"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.87",
+]
 
 [[package]]
 name = "bytes"
@@ -1489,6 +1503,7 @@ name = "shrooms-vb-native"
 version = "0.1.0"
 dependencies = [
  "anyhow",
+ "bytemuck",
  "cc",
  "clap",
  "imgui",
diff --git a/Cargo.toml b/Cargo.toml
index 2b1203f..8820305 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -5,6 +5,7 @@ edition = "2021"
 
 [dependencies]
 anyhow = "1"
+bytemuck = { version = "1", features = ["derive"] }
 clap = { version = "4", features = ["derive"] }
 imgui = "0.12"
 imgui-wgpu = { git = "https://github.com/Yatekii/imgui-wgpu-rs", rev = "2edd348" }
diff --git a/src/anaglyph.wgsl b/src/anaglyph.wgsl
index 796e7b1..0483665 100644
--- a/src/anaglyph.wgsl
+++ b/src/anaglyph.wgsl
@@ -41,9 +41,15 @@ var u_texture: texture_2d<f32>;
 @group(0) @binding(1)
 var u_sampler: sampler;
 
+struct Colors {
+    left: vec4<f32>,
+    right: vec4<f32>,
+};
+@group(0) @binding(2)
+var<uniform> colors: Colors;
 
 @fragment
 fn fs_main(in: VertexOutput) -> @location(0) vec4<f32> {
-    return textureSample(u_texture, u_sampler, in.tex_coords);
-    // return vec4<f32>(0.3, 0.2, 0.1, 1.0);
+    let brt = textureSample(u_texture, u_sampler, in.tex_coords);
+    return colors.left * brt[0] + colors.right * brt[1];
 }
diff --git a/src/app.rs b/src/app.rs
index c196d8f..ae029ef 100644
--- a/src/app.rs
+++ b/src/app.rs
@@ -3,6 +3,7 @@ use imgui_wgpu::{Renderer, RendererConfig};
 use imgui_winit_support::WinitPlatform;
 use pollster::block_on;
 use std::{sync::Arc, time::Instant};
+use wgpu::util::DeviceExt as _;
 #[cfg(target_os = "windows")]
 use winit::platform::windows::{CornerPreference, WindowAttributesExtWindows as _};
 use winit::{
@@ -79,6 +80,15 @@ impl AppWindow {
         }));
         let eyes = eyes.create_view(&wgpu::TextureViewDescriptor::default());
         let sampler = device.create_sampler(&wgpu::SamplerDescriptor::default());
+        let colors = Colors {
+            left: [1.0, 0.0, 0.0, 1.0],
+            right: [0.0, 0.7734375, 0.9375, 1.0],
+        };
+        let color_buf = device.create_buffer_init(&wgpu::util::BufferInitDescriptor {
+            label: Some("colors"),
+            contents: bytemuck::bytes_of(&colors),
+            usage: wgpu::BufferUsages::UNIFORM | wgpu::BufferUsages::COPY_DST,
+        });
         let texture_bind_group_layout =
             device.create_bind_group_layout(&wgpu::BindGroupLayoutDescriptor {
                 label: Some("texture bind group layout"),
@@ -99,6 +109,16 @@ impl AppWindow {
                         ty: wgpu::BindingType::Sampler(wgpu::SamplerBindingType::Filtering),
                         count: None,
                     },
+                    wgpu::BindGroupLayoutEntry {
+                        binding: 2,
+                        visibility: wgpu::ShaderStages::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 {
@@ -113,6 +133,10 @@ impl AppWindow {
                     binding: 1,
                     resource: wgpu::BindingResource::Sampler(&sampler),
                 },
+                wgpu::BindGroupEntry {
+                    binding: 2,
+                    resource: color_buf.as_entire_binding(),
+                },
             ],
         });
 
@@ -438,3 +462,10 @@ impl ApplicationHandler for App {
         );
     }
 }
+
+#[derive(Clone, Copy, bytemuck::Pod, bytemuck::Zeroable)]
+#[repr(C)]
+struct Colors {
+    left: [f32; 4],
+    right: [f32; 4],
+}