Remove offset argument from TrackedRenderPass::set_index_buffer (#20468)

# Objective

- `offset` argument is misleading as the argument is not actually passed
to wgpu (used only for memoization and logging). `BufferSlice` already
contains an offset.
- wgpu's `set_index_buffer` [sets the offset according to
BufferSlice::offset](https://github.com/gfx-rs/wgpu/blob/e990388af98e4b4dff9f7fcc09a4eb5d2f71d227/wgpu/src/api/render_pass.rs#L98-L105)
- `TrackedRenderPass::set_vertex_buffer` was made aware of slice size
(#14916) but missed `set_index_buffer` counterpart

## Solution

- Removed `offset` argument from `TrackedRenderPass::set_index_buffer`
- Apply fix from #14916 to `TrackedRenderPass::is_index_buffer_set`
- ~~Cleanup code by using the newly added `BufferSlice` getters~~ split
out to #21289

## Testing

- Ran a few examples

Author: akimakinai

crates/bevy_pbr/src/render/mesh.rs

@@ -3154,7 +3154,7 @@ impl<P: PhaseItem> RenderCommand<P> for DrawMesh {
                     return RenderCommandResult::Skip;
                 };
 
-                pass.set_index_buffer(index_buffer_slice.buffer.slice(..), 0, *index_format);
+                pass.set_index_buffer(index_buffer_slice.buffer.slice(..), *index_format);
 
                 match item.extra_index() {
                     PhaseItemExtraIndex::None | PhaseItemExtraIndex::DynamicOffset(_) => {

crates/bevy_render/src/render_phase/draw_state.rs

@@ -15,6 +15,8 @@ use wgpu::{IndexFormat, QuerySet, RenderPass};
 #[cfg(feature = "detailed_trace")]
 use tracing::trace;
 
+type BufferSliceKey = (BufferId, wgpu::BufferAddress, wgpu::BufferSize);
+
 /// Tracks the state of a [`TrackedRenderPass`].
 ///
 /// This is used to skip redundant operations on the [`TrackedRenderPass`] (e.g. setting an already
@@ -25,8 +27,8 @@ struct DrawState {
     pipeline: Option<RenderPipelineId>,
     bind_groups: Vec<(Option<BindGroupId>, Vec<u32>)>,
     /// List of vertex buffers by [`BufferId`], offset, and size. See [`DrawState::buffer_slice_key`]
-    vertex_buffers: Vec<Option<(BufferId, wgpu::BufferAddress, wgpu::BufferSize)>>,
-    index_buffer: Option<(BufferId, u64, IndexFormat)>,
+    vertex_buffers: Vec<Option<BufferSliceKey>>,
+    index_buffer: Option<(BufferSliceKey, IndexFormat)>,
 
     /// Stores whether this state is populated or empty for quick state invalidation
     stores_state: bool,
@@ -87,10 +89,7 @@ impl DrawState {
     }
 
     /// Returns the value used for checking whether `BufferSlice`s are equivalent.
-    fn buffer_slice_key(
-        &self,
-        buffer_slice: &BufferSlice,
-    ) -> (BufferId, wgpu::BufferAddress, wgpu::BufferSize) {
+    fn buffer_slice_key(&self, buffer_slice: &BufferSlice) -> BufferSliceKey {
         (
             buffer_slice.id(),
             buffer_slice.offset(),
@@ -99,19 +98,14 @@ impl DrawState {
     }
 
     /// Marks the index `buffer` as bound.
-    fn set_index_buffer(&mut self, buffer: BufferId, offset: u64, index_format: IndexFormat) {
-        self.index_buffer = Some((buffer, offset, index_format));
+    fn set_index_buffer(&mut self, buffer_slice: &BufferSlice, index_format: IndexFormat) {
+        self.index_buffer = Some((self.buffer_slice_key(buffer_slice), index_format));
         self.stores_state = true;
     }
 
     /// Checks, whether the index `buffer` is already bound.
-    fn is_index_buffer_set(
-        &self,
-        buffer: BufferId,
-        offset: u64,
-        index_format: IndexFormat,
-    ) -> bool {
-        self.index_buffer == Some((buffer, offset, index_format))
+    fn is_index_buffer_set(&self, buffer: &BufferSlice, index_format: IndexFormat) -> bool {
+        self.index_buffer == Some((self.buffer_slice_key(buffer), index_format))
     }
 
     /// Resets tracking state
@@ -259,29 +253,21 @@ impl<'a> TrackedRenderPass<'a> {
     ///
     /// Subsequent calls to [`TrackedRenderPass::draw_indexed`] will use the buffer referenced by
     /// `buffer_slice` as the source index buffer.
-    pub fn set_index_buffer(
-        &mut self,
-        buffer_slice: BufferSlice<'a>,
-        offset: u64,
-        index_format: IndexFormat,
-    ) {
-        if self
-            .state
-            .is_index_buffer_set(buffer_slice.id(), offset, index_format)
-        {
-            #[cfg(feature = "detailed_trace")]
-            trace!(
-                "set index buffer (already set): {:?} ({})",
-                buffer_slice.id(),
-                offset
-            );
+    pub fn set_index_buffer(&mut self, buffer_slice: BufferSlice<'a>, index_format: IndexFormat) {
+        let already_set = self.state.is_index_buffer_set(&buffer_slice, index_format);
+        #[cfg(feature = "detailed_trace")]
+        trace!(
+            "set index buffer{}: {:?} (offset = {}, size = {})",
+            if already_set { " (already set)" } else { "" },
+            buffer_slice.id(),
+            buffer_slice.offset(),
+            buffer_slice.size(),
+        );
+        if already_set {
             return;
         }
-        #[cfg(feature = "detailed_trace")]
-        trace!("set index buffer: {:?} ({})", buffer_slice.id(), offset);
         self.pass.set_index_buffer(*buffer_slice, index_format);
-        self.state
-            .set_index_buffer(buffer_slice.id(), offset, index_format);
+        self.state.set_index_buffer(&buffer_slice, index_format);
     }
 
     /// Draws primitives from the active vertex buffer(s).

crates/bevy_sprite_render/src/mesh2d/mesh.rs

@@ -862,7 +862,7 @@ impl<P: PhaseItem> RenderCommand<P> for DrawMesh2d {
                     return RenderCommandResult::Skip;
                 };
 
-                pass.set_index_buffer(index_buffer_slice.buffer.slice(..), 0, *index_format);
+                pass.set_index_buffer(index_buffer_slice.buffer.slice(..), *index_format);
 
                 pass.draw_indexed(
                     index_buffer_slice.range.start..(index_buffer_slice.range.start + count),

crates/bevy_sprite_render/src/render/mod.rs

@@ -947,7 +947,6 @@ impl<P: PhaseItem> RenderCommand<P> for DrawSpriteBatch {
 
         pass.set_index_buffer(
             sprite_meta.sprite_index_buffer.buffer().unwrap().slice(..),
-            0,
             IndexFormat::Uint32,
         );
         pass.set_vertex_buffer(

crates/bevy_ui_render/src/box_shadow.rs

@@ -559,7 +559,7 @@ impl<P: PhaseItem> RenderCommand<P> for DrawBoxShadow {
         // Store the vertices
         pass.set_vertex_buffer(0, vertices.slice(..));
         // Define how to "connect" the vertices
-        pass.set_index_buffer(indices.slice(..), 0, IndexFormat::Uint32);
+        pass.set_index_buffer(indices.slice(..), IndexFormat::Uint32);
         // Draw the vertices
         pass.draw_indexed(batch.range.clone(), 0, 0..1);
         RenderCommandResult::Success

crates/bevy_ui_render/src/gradient.rs

@@ -966,7 +966,7 @@ impl<P: PhaseItem> RenderCommand<P> for DrawGradient {
         // Store the vertices
         pass.set_vertex_buffer(0, vertices.slice(..));
         // Define how to "connect" the vertices
-        pass.set_index_buffer(indices.slice(..), 0, IndexFormat::Uint32);
+        pass.set_index_buffer(indices.slice(..), IndexFormat::Uint32);
         // Draw the vertices
         pass.draw_indexed(batch.range.clone(), 0, 0..1);
         RenderCommandResult::Success

crates/bevy_ui_render/src/render_pass.rs

@@ -267,7 +267,6 @@ impl<P: PhaseItem> RenderCommand<P> for DrawUiNode {
         // Define how to "connect" the vertices
         pass.set_index_buffer(
             indices.slice(..),
-            0,
             bevy_render::render_resource::IndexFormat::Uint32,
         );
         // Draw the vertices

crates/bevy_ui_render/src/ui_texture_slice_pipeline.rs

@@ -706,7 +706,7 @@ impl<P: PhaseItem> RenderCommand<P> for DrawSlicer {
         // Store the vertices
         pass.set_vertex_buffer(0, vertices.slice(..));
         // Define how to "connect" the vertices
-        pass.set_index_buffer(indices.slice(..), 0, IndexFormat::Uint32);
+        pass.set_index_buffer(indices.slice(..), IndexFormat::Uint32);
         // Draw the vertices
         pass.draw_indexed(batch.range.clone(), 0, 0..1);
         RenderCommandResult::Success

examples/shader_advanced/custom_phase_item.rs

@@ -93,7 +93,6 @@ where
                 .buffer()
                 .unwrap()
                 .slice(..),
-            0,
             IndexFormat::Uint32,
         );
 

examples/shader_advanced/custom_shader_instancing.rs

@@ -303,7 +303,7 @@ impl<P: PhaseItem> RenderCommand<P> for DrawMeshInstanced {
                     return RenderCommandResult::Skip;
                 };
 
-                pass.set_index_buffer(index_buffer_slice.buffer.slice(..), 0, *index_format);
+                pass.set_index_buffer(index_buffer_slice.buffer.slice(..), *index_format);
                 pass.draw_indexed(
                     index_buffer_slice.range.start..(index_buffer_slice.range.start + count),
                     vertex_buffer_slice.range.start as i32,