refactor: separate shaders (#21)

* refactor: separate shaders

* feat: transform separation and shader entrypoint correction

src/render/bindings.wgsl

@@ -0,0 +1,56 @@
+#define_import_path bevy_gaussian_splatting::bindings
+
+#import bevy_render::globals::Globals
+#import bevy_render::view::View
+
+
+struct GaussianInput {
+    @location(0) rotation: vec4<f32>,
+    @location(1) position: vec4<f32>,
+    @location(2) scale_opacity: vec4<f32>,
+    sh: array<f32, #{MAX_SH_COEFF_COUNT}>,
+};
+
+struct GaussianOutput {
+    @builtin(position) position: vec4<f32>,
+    @location(0) @interpolate(flat) color: vec4<f32>,
+    @location(1) @interpolate(flat) conic: vec3<f32>,
+    @location(2) @interpolate(linear) uv: vec2<f32>,
+    @location(3) @interpolate(linear) major_minor: vec2<f32>,
+};
+
+struct GaussianUniforms {
+    global_transform: mat4x4<f32>,
+    global_scale: f32,
+};
+
+struct DrawIndirect {
+    vertex_count: u32,
+    instance_count: atomic<u32>,
+    base_vertex: u32,
+    base_instance: u32,
+}
+struct SortingGlobal {
+    status_counters: array<array<atomic<u32>, #{RADIX_BASE}>, #{MAX_TILE_COUNT_C}>,
+    digit_histogram: array<array<atomic<u32>, #{RADIX_BASE}>, #{RADIX_DIGIT_PLACES}>,
+    assignment_counter: atomic<u32>,
+}
+struct Entry {
+    key: u32,
+    value: u32,
+}
+
+
+@group(0) @binding(0) var<uniform> view: View;
+@group(0) @binding(1) var<uniform> globals: Globals;
+
+@group(1) @binding(0) var<uniform> uniforms: GaussianUniforms;
+
+@group(2) @binding(0) var<storage, read> points: array<GaussianInput>;
+
+@group(3) @binding(0) var<uniform> sorting_pass_index: u32;
+@group(3) @binding(1) var<storage, read_write> sorting: SortingGlobal;
+@group(3) @binding(2) var<storage, read_write> draw_indirect: DrawIndirect;
+@group(3) @binding(3) var<storage, read_write> input_entries: array<Entry>;
+@group(3) @binding(4) var<storage, read_write> output_entries: array<Entry>;
+@group(3) @binding(5) var<storage, read> sorted_entries: array<Entry>;