fix(engine): disable old mesh vertex attrs even if not consecutive

2 files changed, 18 insertions, 87 deletions

diff --git a/engine/src/rendering/backend/opengl/graphics_mesh.rs b/engine/src/rendering/backend/opengl/graphics_mesh.rs
index 29ae01a..a3f4197 100644
--- a/engine/src/rendering/backend/opengl/graphics_mesh.rs
+++ b/engine/src/rendering/backend/opengl/graphics_mesh.rs
@@ -17,7 +17,6 @@ use crate::rendering::shader::{
     VertexInputSemName,
 };
 use crate::rendering::MeshUsage;
-use crate::util::DisplaySlice;
 
 const VERTEX_BUF_BINDING_INDEX: u32 = 0;
 
@@ -27,7 +26,7 @@ pub struct GraphicsMesh
     /// Vertex and index buffer has to live as long as the vertex array
     vertex_buffer: GlBuffer<u8>,
     vertex_attr_props: Vec<MeshVertexAttrProperties>,
-    last_used_vertex_attr_cnt: u32,
+    last_max_vertex_attr_index: u32,
     pub index_buffer: Option<GlBuffer<u32>>,
     pub element_cnt: u32,
     pub vertex_arr: GlVertexArray,
@@ -89,7 +88,7 @@ impl GraphicsMesh
             return Ok(Self {
                 vertex_buffer: vertex_buffer,
                 vertex_attr_props: mesh.vertex_buf().vertex_attr_props().to_vec(),
-                last_used_vertex_attr_cnt: 0,
+                last_max_vertex_attr_index: 0,
                 index_buffer: Some(index_buffer),
                 element_cnt: indices
                     .len()
@@ -102,7 +101,7 @@ impl GraphicsMesh
         Ok(Self {
             vertex_buffer: vertex_buffer,
             vertex_attr_props: mesh.vertex_buf().vertex_attr_props().to_vec(),
-            last_used_vertex_attr_cnt: 0,
+            last_max_vertex_attr_index: 0,
             index_buffer: None,
             element_cnt: mesh
                 .vertex_buf()
@@ -161,26 +160,24 @@ impl GraphicsMesh
         shader_vertex_desc: &ShaderVertexDescription,
     ) -> Result<(), VertexAttrsUpdatingError>
     {
-        let vertex_input_cnt = u32::try_from(shader_vertex_desc.inputs.len())
-            .expect("Shader has too many vertex inputs. Count does not fit into u32");
-
-        if self.last_used_vertex_attr_cnt > vertex_input_cnt {
-            for index in vertex_input_cnt..self.last_used_vertex_attr_cnt {
-                self.vertex_arr.disable_attrib(curr_gl_ctx, index);
-            }
+        for index in 0..self.last_max_vertex_attr_index {
+            self.vertex_arr.disable_attrib(curr_gl_ctx, index);
         }
 
-        let mut used_vertex_attr_cnt = 0u32;
+        let mut max_vertex_attr_index = 0u32;
 
-        for vertex_attr_props in &self.vertex_attr_props {
-            let Some(vertex_input_desc) =
-                shader_vertex_desc.inputs.iter().find(|vertex_input_desc| {
+        for vertex_input_desc in &*shader_vertex_desc.inputs {
+            let Some(vertex_attr_props) =
+                self.vertex_attr_props.iter().find(|vertex_attr_props| {
                     vertex_input_desc
                         .semantic_name
                         .matches_vertex_label(&vertex_attr_props.label)
                 })
             else {
-                continue;
+                cold_path();
+                return Err(VertexAttrsUpdatingError::MissingVertexAttr(
+                    vertex_input_desc.semantic_name.clone(),
+                ));
             };
 
             let attrib_index: u32 = vertex_input_desc.index.try_into().unwrap();
@@ -214,32 +211,10 @@ impl GraphicsMesh
                 VERTEX_BUF_BINDING_INDEX,
             );
 
-            used_vertex_attr_cnt += 1;
+            max_vertex_attr_index = max_vertex_attr_index.max(attrib_index);
         }
 
-        self.last_used_vertex_attr_cnt = used_vertex_attr_cnt;
-
-        if used_vertex_attr_cnt as usize != shader_vertex_desc.inputs.len() {
-            cold_path();
-
-            return Err(VertexAttrsUpdatingError::MissingVertexAttrs(
-                shader_vertex_desc
-                    .inputs
-                    .iter()
-                    .filter_map(|vertex_input_desc| {
-                        if self.vertex_attr_props.iter().any(|props| {
-                            vertex_input_desc
-                                .semantic_name
-                                .matches_vertex_label(&props.label)
-                        }) {
-                            return None;
-                        }
-
-                        Some(vertex_input_desc.semantic_name.clone())
-                    })
-                    .collect(),
-            ));
-        }
+        self.last_max_vertex_attr_index = max_vertex_attr_index;
 
         Ok(())
     }
@@ -269,10 +244,9 @@ pub enum Error
 pub enum VertexAttrsUpdatingError
 {
     #[error(
-        "Mesh is missing equivalent vertex attribute(s) for shader's vertex inputs: {}",
-        DisplaySlice::new(.0)
+        "Mesh is missing equivalent vertex attribute for shader's vertex input: {0}"
     )]
-    MissingVertexAttrs(Vec<VertexInputSemName>),
+    MissingVertexAttr(VertexInputSemName),
 }
 
 fn mesh_usage_to_gl_buffer_usage(mesh_usage: MeshUsage) -> GlBufferUsage
diff --git a/engine/src/util.rs b/engine/src/util.rs
index a7caa2a..f016ad3 100644
--- a/engine/src/util.rs
+++ b/engine/src/util.rs
@@ -1,4 +1,4 @@
-use std::fmt::{Debug, Display};
+use std::fmt::Debug;
 
 use crate::ecs::util::StreamingIterator;
 
@@ -28,49 +28,6 @@ impl<T> OptionExt<T> for Option<T>
     }
 }
 
-pub struct DisplaySlice<'a, Item>
-{
-    slice: &'a [Item],
-}
-
-impl<'a, Item> DisplaySlice<'a, Item>
-{
-    pub fn new(slice: &'a [Item]) -> Self
-    {
-        Self { slice }
-    }
-}
-
-impl<Item> Display for DisplaySlice<'_, Item>
-where
-    Item: Display,
-{
-    fn fmt(&self, formatter: &mut std::fmt::Formatter<'_>) -> std::fmt::Result
-    {
-        let Some(first_item) = self.slice.first() else {
-            return formatter.write_str("<empty>");
-        };
-
-        write!(formatter, "{first_item}")?;
-
-        if self.slice.len() == 1 {
-            return Ok(());
-        }
-
-        for item in &self.slice[1..self.slice.len() - 1] {
-            write!(formatter, ", {item}")?;
-        }
-
-        let Some(last_item) = self.slice.last() else {
-            unreachable!();
-        };
-
-        write!(formatter, " & {last_item}")?;
-
-        Ok(())
-    }
-}
-
 #[derive(Debug)]
 pub struct BitArray<const SIZE: usize, const BITS_PER_ITEM: usize>
 {