Add gltfscenerendering rust shader

Author: LegNeato

shaders/rust/Cargo.lock

@@ -34,6 +34,7 @@ members = [
     "dynamicuniformbuffer/base",
     "gears",
     "gltfloading/mesh",
+    "gltfscenerendering/scene",
     "hdr/bloom",
     "hdr/composition",
     "hdr/gbuffer",

shaders/rust/Cargo.toml

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

shaders/rust/gltfscenerendering/scene.frag.spv

@@ -0,0 +1,101 @@
+#![cfg_attr(target_arch = "spirv", no_std)]
+#![allow(clippy::missing_safety_doc)]
+
+use spirv_std::{spirv, glam::{mat3, vec3, vec4, Mat3, Mat4, Vec2, Vec3, Vec4}, Image, num_traits::Float};
+use spirv_std::image::SampledImage;
+
+#[repr(C)]
+#[derive(Copy, Clone)]
+pub struct UboScene {
+    pub projection: Mat4,
+    pub view: Mat4,
+    pub light_pos: Vec4,
+    pub view_pos: Vec4,
+}
+
+#[repr(C)]
+#[derive(Copy, Clone)]
+pub struct PushConsts {
+    pub model: Mat4,
+}
+
+#[spirv(vertex)]
+pub fn main_vs(
+    in_pos: Vec3,
+    in_normal: Vec3,
+    in_uv: Vec2,
+    in_color: Vec3,
+    in_tangent: Vec4,
+    #[spirv(uniform, descriptor_set = 0, binding = 0)] ubo_scene: &UboScene,
+    #[spirv(push_constant)] push_consts: &PushConsts,
+    #[spirv(position)] out_position: &mut Vec4,
+    out_normal: &mut Vec3,
+    out_color: &mut Vec3,
+    out_uv: &mut Vec2,
+    out_view_vec: &mut Vec3,
+    out_light_vec: &mut Vec3,
+    out_tangent: &mut Vec4,
+) {
+    *out_normal = in_normal;
+    *out_color = in_color;
+    *out_uv = in_uv;
+    *out_tangent = in_tangent;
+    *out_position = ubo_scene.projection * ubo_scene.view * push_consts.model * vec4(in_pos.x, in_pos.y, in_pos.z, 1.0);
+    
+    let model_mat3 = mat3(
+        push_consts.model.x_axis.truncate(),
+        push_consts.model.y_axis.truncate(),
+        push_consts.model.z_axis.truncate(),
+    );
+    *out_normal = model_mat3 * in_normal;
+    let pos = push_consts.model * vec4(in_pos.x, in_pos.y, in_pos.z, 1.0);
+    *out_light_vec = ubo_scene.light_pos.truncate() - pos.truncate();
+    *out_view_vec = ubo_scene.view_pos.truncate() - pos.truncate();
+}
+
+#[cfg_attr(target_arch = "spirv", spirv(fragment))]
+pub fn main_fs(
+    in_normal: Vec3,
+    in_color: Vec3,
+    in_uv: Vec2,
+    in_view_vec: Vec3,
+    in_light_vec: Vec3,
+    in_tangent: Vec4,
+    #[spirv(descriptor_set = 1, binding = 0)] sampler_color_map: &SampledImage<Image!(2D, type=f32, sampled)>,
+    #[spirv(descriptor_set = 1, binding = 1)] sampler_normal_map: &SampledImage<Image!(2D, type=f32, sampled)>,
+    #[spirv(spec_constant(id = 0, default = 0))] alpha_mask: u32,
+    #[spirv(spec_constant(id = 1, default = 0))] alpha_mask_cutoff_bits: u32,
+    out_frag_color: &mut Vec4,
+) {
+    let color = sampler_color_map.sample(in_uv) * vec4(in_color.x, in_color.y, in_color.z, 1.0);
+
+    let alpha_mask_enabled = alpha_mask != 0;
+    let alpha_mask_cutoff = f32::from_bits(alpha_mask_cutoff_bits);
+    
+    if alpha_mask_enabled {
+        if color.w < alpha_mask_cutoff {
+            #[cfg(target_arch = "spirv")]
+            spirv_std::arch::kill();
+        }
+    }
+
+    let mut n = in_normal.normalize();
+    let t = in_tangent.truncate().normalize();
+    let b = in_normal.cross(in_tangent.truncate()) * in_tangent.w;
+    let tbn = Mat3::from_cols(t, b, n);
+    let normal_sample = sampler_normal_map.sample(in_uv).truncate() * 2.0 - vec3(1.0, 1.0, 1.0);
+    n = tbn * normal_sample.normalize();
+
+    const AMBIENT: f32 = 0.1;
+    let l = in_light_vec.normalize();
+    let v = in_view_vec.normalize();
+    let r = (-l).reflect(n);
+    let diffuse = vec3(n.dot(l).max(AMBIENT), n.dot(l).max(AMBIENT), n.dot(l).max(AMBIENT));
+    let specular = r.dot(v).max(0.0).powf(32.0);
+    *out_frag_color = vec4(
+        diffuse.x * color.x + specular,
+        diffuse.y * color.y + specular,
+        diffuse.z * color.z + specular,
+        color.w
+    );
+}