refactor(opengl-bindings): make VertexArray::bind_vertex_buffer take vertex size

1 files changed, 41 insertions, 23 deletions

diff --git a/opengl-bindings/src/vertex_array.rs b/opengl-bindings/src/vertex_array.rs
index 5d80c0c..3dc5cb6 100644
--- a/opengl-bindings/src/vertex_array.rs
+++ b/opengl-bindings/src/vertex_array.rs
@@ -1,5 +1,4 @@
-use std::ffi::{c_int, c_void};
-use std::mem::size_of;
+use std::ffi::c_void;
 
 use safer_ffi::layout::ReprC;
 
@@ -107,15 +106,29 @@ impl VertexArray
         }
     }
 
-    pub fn bind_vertex_buffer<VertexT: ReprC>(
+    pub fn bind_vertex_buffer<VertexBufferItem: ReprC>(
         &self,
         current_context: &CurrentContextWithFns<'_>,
         binding_index: u32,
-        vertex_buffer: &Buffer<VertexT>,
-        offset: isize,
-    )
+        vertex_buffer: &Buffer<VertexBufferItem>,
+        vertex_buffer_spec: VertexBufferSpec,
+    ) -> Result<(), BindVertexBufferError>
     {
-        let vertex_size = const { cast_usize_to_c_int(size_of::<VertexT>()) };
+        let offset: crate::sys::types::GLintptr = vertex_buffer_spec
+            .offset
+            .try_into()
+            .map_err(|_| BindVertexBufferError::OffsetValueTooLarge {
+                value: vertex_buffer_spec.offset,
+                max_value: crate::sys::types::GLintptr::MAX as usize,
+            })?;
+
+        let vertex_size: crate::sys::types::GLsizei = vertex_buffer_spec
+            .vertex_size
+            .try_into()
+            .map_err(|_| BindVertexBufferError::VertexSizeValueTooLarge {
+                value: vertex_buffer_spec.vertex_size,
+                max_value: crate::sys::types::GLsizei::MAX as usize,
+            })?;
 
         unsafe {
             current_context.fns().VertexArrayVertexBuffer(
@@ -126,6 +139,8 @@ impl VertexArray
                 vertex_size,
             );
         }
+
+        Ok(())
     }
 
     pub fn enable_attrib(
@@ -239,6 +254,13 @@ pub struct AttributeFormat
     pub offset: u32,
 }
 
+#[derive(Debug, Clone)]
+pub struct VertexBufferSpec
+{
+    pub offset: usize,
+    pub vertex_size: usize,
+}
+
 #[derive(Debug, thiserror::Error)]
 pub enum DrawError
 {
@@ -255,22 +277,18 @@ pub enum DrawError
     },
 }
 
-const fn cast_usize_to_c_int(num: usize) -> c_int
-{
-    assert!(num <= c_int::MAX.cast_unsigned() as usize);
-
-    c_int::from_ne_bytes(shorten_byte_array(num.to_ne_bytes()))
-}
-
-const fn shorten_byte_array<const SRC_LEN: usize, const DST_LEN: usize>(
-    src: [u8; SRC_LEN],
-) -> [u8; DST_LEN]
+#[derive(Debug, thiserror::Error)]
+pub enum BindVertexBufferError
 {
-    assert!(DST_LEN < SRC_LEN);
-
-    let mut ret = [0; DST_LEN];
-
-    ret.copy_from_slice(src.split_at(DST_LEN).0);
+    #[error("Offset value {value} is too large. Must be < {max_value}")]
+    OffsetValueTooLarge
+    {
+        value: usize, max_value: usize
+    },
 
-    ret
+    #[error("Vertex size value {value} is too large. Must be < {max_value}")]
+    VertexSizeValueTooLarge
+    {
+        value: usize, max_value: usize
+    },
 }