1 files changed, 76 insertions, 0 deletions
diff --git a/src/pipeline/vertex/vertex.rs b/src/pipeline/vertex/vertex.rs
new file mode 100644
index 0000000..728fcaa
--- /dev/null
+++ b/src/pipeline/vertex/vertex.rs
@@ -0,0 +1,76 @@
+// Copyright (c) 2017 The vulkano developers
+// Licensed under the Apache License, Version 2.0
+// <LICENSE-APACHE or
+// https://www.apache.org/licenses/LICENSE-2.0> or the MIT
+// license <LICENSE-MIT or https://opensource.org/licenses/MIT>,
+// at your option. All files in the project carrying such
+// notice may not be copied, modified, or distributed except
+// according to those terms.
+
+use crate::format::Format;
+
+/// Describes an individual `Vertex`. In other words a collection of attributes that can be read
+/// from a vertex shader.
+///
+/// At this stage, the vertex is in a "raw" format. For example a `[f32; 4]` can match both a
+/// `vec4` or a `float[4]`. The way the things are bound depends on the shader.
+pub unsafe trait Vertex: 'static + Send + Sync {
+    /// Returns the characteristics of a vertex member by its name.
+    fn member(name: &str) -> Option<VertexMemberInfo>;
+}
+
+unsafe impl Vertex for () {
+    #[inline]
+    fn member(_: &str) -> Option<VertexMemberInfo> {
+        None
+    }
+}
+
+/// Information about a member of a vertex struct.
+pub struct VertexMemberInfo {
+    /// Offset of the member in bytes from the start of the struct.
+    pub offset: usize,
+    /// Type of data. This is used to check that the interface is matching.
+    pub ty: VertexMemberTy,
+    /// Number of consecutive elements of that type.
+    pub array_size: usize,
+}
+
+/// Type of a member of a vertex struct.
+#[derive(Debug, Copy, Clone, PartialEq, Eq)]
+#[allow(missing_docs)]
+pub enum VertexMemberTy {
+    I8,
+    U8,
+    I16,
+    U16,
+    I32,
+    U32,
+    F32,
+    F64,
+}
+
+impl VertexMemberTy {
+    /// Returns true if a combination of `(type, array_size)` matches a format.
+    #[inline]
+    pub fn matches(&self, array_size: usize, format: Format, num_locs: u32) -> bool {
+        // TODO: implement correctly
+        let my_size = match *self {
+            VertexMemberTy::I8 => 1,
+            VertexMemberTy::U8 => 1,
+            VertexMemberTy::I16 => 2,
+            VertexMemberTy::U16 => 2,
+            VertexMemberTy::I32 => 4,
+            VertexMemberTy::U32 => 4,
+            VertexMemberTy::F32 => 4,
+            VertexMemberTy::F64 => 8,
+        };
+
+        let format_size = match format.size() {
+            None => return false,
+            Some(s) => s,
+        } as usize;
+
+        array_size * my_size == format_size * num_locs as usize
+    }
+}