Add instances support

src/core/render/primitives/transform.rs

@@ -1,9 +1,26 @@
+use std::sync::Arc;
+
 use glam::{Mat4, Quat, Vec3};
+use vulkano::{
+    Validated,
+    buffer::{
+        AllocateBufferError, Buffer, BufferContents, BufferCreateInfo, BufferUsage, Subbuffer,
+    },
+    memory::allocator::{AllocationCreateInfo, MemoryTypeFilter, StandardMemoryAllocator},
+    pipeline::graphics::vertex_input::Vertex,
+};
 
 pub struct Transform {
-    position: Vec3,
-    rotation: Quat,
-    scale: Vec3,
+    pub position: Vec3,
+    pub rotation: Quat,
+    pub scale: Vec3,
+}
+
+#[derive(BufferContents, Vertex)]
+#[repr(C)]
+pub struct TransformRaw {
+    #[format(R32G32B32A32_SFLOAT)]
+    pub model: [[f32; 4]; 4],
 }
 
 impl Default for Transform {
@@ -29,9 +46,35 @@ impl Transform {
         self.scale *= scale;
     }
 
-    pub fn get_mat4(&self) -> Mat4 {
-        Mat4::from_translation(self.position)
-            * Mat4::from_quat(self.rotation)
-            * Mat4::from_scale(self.scale)
+    pub fn into_raw(&self) -> TransformRaw {
+        TransformRaw {
+            model: (Mat4::from_translation(self.position)
+                * Mat4::from_quat(self.rotation)
+                * Mat4::from_scale(self.scale))
+            .to_cols_array_2d(),
+        }
+    }
+
+    pub fn create_buffer(
+        memory_allocator: &Arc<StandardMemoryAllocator>,
+        transforms: &[Transform],
+    ) -> Result<Subbuffer<[TransformRaw]>, Validated<AllocateBufferError>> {
+        let transform_raws: Vec<TransformRaw> = transforms.iter().map(|t| t.into_raw()).collect();
+
+        let buffer = Buffer::from_iter(
+            memory_allocator.clone(),
+            BufferCreateInfo {
+                usage: BufferUsage::VERTEX_BUFFER,
+                ..Default::default()
+            },
+            AllocationCreateInfo {
+                memory_type_filter: MemoryTypeFilter::PREFER_DEVICE
+                    | MemoryTypeFilter::HOST_SEQUENTIAL_WRITE,
+                ..Default::default()
+            },
+            transform_raws,
+        )?;
+
+        Ok(buffer)
     }
 }

src/core/render/primitives/vertex.rs

@@ -10,3 +10,13 @@ pub struct Vertex2D {
     #[format(R32G32_SFLOAT)]
     pub uv: [f32; 2],
 }
+
+#[derive(BufferContents, Vertex)]
+#[repr(C)]
+pub struct Vertex3D {
+    #[format(R32G32B32_SFLOAT)]
+    pub position: [f32; 3],
+
+    #[format(R32G32_SFLOAT)]
+    pub uv: [f32; 2],
+}