Add texturemipmapgen rust shader

Author: LegNeato

shaders/rust/Cargo.lock

@@ -92,6 +92,7 @@ members = [
     "multiview/viewdisplay",
     "imgui/ui",
     "imgui/scene",
+    "texturemipmapgen/texture",
 ]
 
 [workspace.dependencies]

shaders/rust/Cargo.toml

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

shaders/rust/texturemipmapgen/texture.frag.spv

@@ -0,0 +1,66 @@
+#![cfg_attr(target_arch = "spirv", no_std)]
+#![allow(clippy::missing_safety_doc)]
+
+use spirv_std::{spirv, glam::{vec2, vec3, vec4, Mat3, Mat4, Vec2, Vec3, Vec4, Vec4Swizzles}, Image, Sampler, num_traits::Float};
+
+#[repr(C)]
+#[derive(Copy, Clone)]
+pub struct Ubo {
+    pub projection: Mat4,
+    pub view: Mat4,
+    pub model: Mat4,
+    pub view_pos: Vec4,
+    pub lod_bias: f32,
+    pub sampler_index: i32,
+}
+
+#[spirv(vertex)]
+pub fn main_vs(
+    in_pos: Vec3,
+    in_uv: Vec2,
+    in_normal: Vec3,
+    #[spirv(uniform, descriptor_set = 0, binding = 0)] ubo: &Ubo,
+    #[spirv(position)] out_position: &mut Vec4,
+    out_uv: &mut Vec2,
+    out_lod_bias: &mut f32,
+    out_normal: &mut Vec3,
+    out_view_vec: &mut Vec3,
+    out_light_vec: &mut Vec3,
+) {
+    *out_uv = in_uv * vec2(2.0, 1.0);
+    *out_lod_bias = ubo.lod_bias;
+
+    let world_pos = (ubo.model * vec4(in_pos.x, in_pos.y, in_pos.z, 1.0)).xyz();
+
+    *out_position = ubo.projection * ubo.view * ubo.model * vec4(in_pos.x, in_pos.y, in_pos.z, 1.0);
+
+    *out_normal = Mat3::from_mat4(ubo.model.inverse().transpose()) * in_normal;
+    let light_pos = vec3(-30.0, 0.0, 0.0);
+    *out_light_vec = world_pos - light_pos;
+    *out_view_vec = ubo.view_pos.xyz() - world_pos;
+}
+
+#[spirv(fragment)]
+pub fn main_fs(
+    in_uv: Vec2,
+    in_lod_bias: f32,
+    in_normal: Vec3,
+    in_view_vec: Vec3,
+    in_light_vec: Vec3,
+    #[spirv(uniform, descriptor_set = 0, binding = 0)] ubo: &Ubo,
+    #[spirv(descriptor_set = 0, binding = 1)] texture_color: &Image!(2D, type=f32, sampled),
+    #[spirv(descriptor_set = 0, binding = 2)] samplers: &[Sampler; 3],
+    out_frag_color: &mut Vec4,
+) {
+    let sampler = &samplers[ubo.sampler_index as usize];
+    let color = texture_color.sample_bias(*sampler, in_uv, in_lod_bias);
+
+    let n = in_normal.normalize();
+    let l = in_light_vec.normalize();
+    let v = in_view_vec.normalize();
+    let r = l.reflect(n);
+    let diffuse = n.dot(l).max(0.65) * vec3(1.0, 1.0, 1.0);
+    let specular = r.dot(v).max(0.0).powf(16.0) * color.w;
+    let final_color = diffuse * color.xyz() + vec3(specular, specular, specular);
+    *out_frag_color = vec4(final_color.x, final_color.y, final_color.z, 1.0);
+}