Add spherical environment mapping rust shaders

Author: LegNeato

shaders/rust/Cargo.lock

@@ -65,6 +65,7 @@ members = [
     "texturecubemap/reflect",
     "texturecubemap/skybox",
     "renderheadless/triangle",
+    "sphericalenvmapping/sem",
 ]
 
 [workspace.dependencies]

shaders/rust/Cargo.toml

@@ -68,7 +68,7 @@ def compile_shader(shader_dir):
                 print(f"  Created {final_path.name} (entry point: {entry_point})")
 
                 # Special case: move to parent directory for nested shader structures
-                if shader_dir.parent.name in ["base", "descriptorsets", "dynamicuniformbuffer", "multisampling", "pipelines", "specializationconstants", "computeshader", "texturearray", "screenshot", "negativeviewportheight", "stencilbuffer", "parallaxmapping", "computecloth", "ssao", "shadowmapping", "deferred", "computenbody", "bloom", "hdr", "radialblur", "pbribl", "indirectdraw", "instancing", "texturecubemap", "renderheadless"]:
+                if shader_dir.parent.name in ["base", "descriptorsets", "dynamicuniformbuffer", "multisampling", "pipelines", "specializationconstants", "computeshader", "texturearray", "screenshot", "negativeviewportheight", "stencilbuffer", "parallaxmapping", "computecloth", "ssao", "shadowmapping", "deferred", "computenbody", "bloom", "hdr", "radialblur", "pbribl", "indirectdraw", "instancing", "texturecubemap", "renderheadless", "sphericalenvmapping"]:
                     parent_dir = shader_dir.parent
                     parent_final_path = parent_dir / f"{shader_name}.{shader_type}.spv"
                     shutil.move(str(final_path), str(parent_final_path))

shaders/rust/compileshaders.py

@@ -0,0 +1,10 @@
+[package]
+name = "sem"
+version = "0.1.0"
+edition = "2021"
+
+[lib]
+crate-type = ["dylib"]
+
+[dependencies]
+spirv-std = { workspace = true }

shaders/rust/sphericalenvmapping/sem.frag.spv

@@ -0,0 +1,69 @@
+#![cfg_attr(target_arch = "spirv", no_std)]
+#![allow(clippy::missing_safety_doc)]
+
+use spirv_std::{spirv, glam::{vec3, vec4, Mat3, Mat4, Vec3, Vec4, Vec3Swizzles}, Image, num_traits::Float};
+use spirv_std::image::SampledImage;
+
+#[repr(C)]
+#[derive(Copy, Clone)]
+pub struct Ubo {
+    pub projection: Mat4,
+    pub model: Mat4,
+    pub normal: Mat4,
+    pub view: Mat4,
+    pub tex_index: i32,
+}
+
+#[spirv(vertex)]
+pub fn main_vs(
+    in_pos: Vec4,
+    in_normal: Vec3,
+    in_color: Vec3,
+    #[spirv(uniform, descriptor_set = 0, binding = 0)] ubo: &Ubo,
+    #[spirv(position)] out_position: &mut Vec4,
+    out_color: &mut Vec3,
+    out_eye_pos: &mut Vec3,
+    out_normal: &mut Vec3,
+    #[spirv(flat)] out_tex_index: &mut i32,
+) {
+    *out_color = in_color;
+    let model_view = ubo.view * ubo.model;
+    *out_eye_pos = (model_view * in_pos).truncate().normalize();
+    *out_tex_index = ubo.tex_index;
+    
+    let normal_mat3 = Mat3::from_cols(
+        ubo.normal.x_axis.truncate(),
+        ubo.normal.y_axis.truncate(),
+        ubo.normal.z_axis.truncate(),
+    );
+    *out_normal = (normal_mat3 * in_normal).normalize();
+    
+    let r = out_eye_pos.reflect(*out_normal);
+    let _m = 2.0 * (r.x.powi(2) + r.y.powi(2) + (r.z + 1.0).powi(2)).sqrt();
+    *out_position = ubo.projection * model_view * in_pos;
+}
+
+#[spirv(fragment)]
+pub fn main_fs(
+    in_color: Vec3,
+    in_eye_pos: Vec3,
+    in_normal: Vec3,
+    #[spirv(flat)] in_tex_index: i32,
+    #[spirv(descriptor_set = 0, binding = 1)] mat_cap: &SampledImage<Image!(2D, type=f32, sampled, arrayed)>,
+    out_frag_color: &mut Vec4,
+) {
+    let r = in_eye_pos.reflect(in_normal);
+    let r2 = vec3(r.x, r.y, r.z + 1.0);
+    let m = 2.0 * r2.length();
+    let v_n = r.xy() / m + 0.5;
+    
+    let tex_coord = vec3(v_n.x, v_n.y, in_tex_index as f32);
+    let sampled_color = mat_cap.sample(tex_coord);
+    
+    *out_frag_color = vec4(
+        sampled_color.x * (in_color.x * 2.0).clamp(0.0, 1.0),
+        sampled_color.y * (in_color.x * 2.0).clamp(0.0, 1.0),
+        sampled_color.z * (in_color.x * 2.0).clamp(0.0, 1.0),
+        1.0
+    );
+}