Move re_renderer examples to its own crate in order to make workspace…

… level examples less confusing (#4472)

### What

This way we don't show renderer examples like "the examples". Also, due
to some dependency issues with the optional re_renderer arrow dependency
(details somewhat unclear..), we were previously no longer able to run
examples on the web. This works nicely now again:

<img width="1953" alt="image"
src="https://github.com/rerun-io/rerun/assets/1220815/87b4c2be-2080-44f2-b319-a222c49315b7">

depicted:
* `cargo run -p re_renderer_examples --bin multiview` (native)
* `cargo run-wasm -p re_renderer_examples --bin multiview --features
"webgl"` (webgl, using firefox here)
* `cargo run-wasm -p re_renderer_examples --bin multiview` (webgpu,
using chrome here)


### Checklist
* [x] I have read and agree to [Contributor
Guide](https://github.com/rerun-io/rerun/blob/main/CONTRIBUTING.md) and
the [Code of
Conduct](https://github.com/rerun-io/rerun/blob/main/CODE_OF_CONDUCT.md)
* [x] I've included a screenshot or gif (if applicable)
* [x] I have tested the web demo (if applicable):
  * Full build: [app.rerun.io](https://app.rerun.io/pr/4472/index.html)
* Partial build:
[app.rerun.io](https://app.rerun.io/pr/4472/index.html?manifest_url=https://app.rerun.io/version/nightly/examples_manifest.json)
- Useful for quick testing when changes do not affect examples in any
way
* [x] The PR title and labels are set such as to maximize their
usefulness for the next release's CHANGELOG

- [PR Build Summary](https://build.rerun.io/pr/4472)
- [Docs
preview](https://rerun.io/preview/504ce9714e120af91374751e7ae86e70b195044c/docs)
<!--DOCS-PREVIEW-->
- [Examples
preview](https://rerun.io/preview/504ce9714e120af91374751e7ae86e70b195044c/examples)
<!--EXAMPLES-PREVIEW-->
- [Recent benchmark results](https://build.rerun.io/graphs/crates.html)
- [Wasm size tracking](https://build.rerun.io/graphs/sizes.html)

ARCHITECTURE.md

@@ -117,6 +117,7 @@ Update instructions:
 | rerun_c   | Rerun C SDK                          |
 | rerun_py  | Rerun Python SDK                     |
 | re_sdk    | Rerun logging SDK                    |
+<!-- | re_renderer_examples    | Examples for re_renderer | -->
 
 
 ### Viewer crates

crates/re_renderer/Cargo.toml

@@ -83,36 +83,8 @@ wgpu-core.workspace = true
 
 # For examples:
 [dev-dependencies]
-image = { workspace = true, default-features = false, features = ["png"] }
-log.workspace = true
-pollster.workspace = true
-rand = { workspace = true, features = ["std", "std_rng"] }
-web-time.workspace = true
-winit.workspace = true
-zip = { workspace = true, default-features = false, features = ["deflate"] }
-
-# For tests:
 unindent.workspace = true
 
-
-[target.'cfg(not(target_arch = "wasm32"))'.dev-dependencies] # native
-async-executor.workspace = true
-
-[target.'cfg(target_arch = "wasm32")'.dev-dependencies] # wasm
-console_error_panic_hook.workspace = true
-# required to make rand work on wasm, see https://github.com/rust-random/rand#wasm-support
-getrandom = { workspace = true, features = ["js"] }
-wasm-bindgen-futures.workspace = true
-web-sys = { workspace = true, features = [
-  "Location",
-  "Blob",
-  "RequestInit",
-  "RequestMode",
-  "Request",
-  "Response",
-] }
-
-
 # For build.rs:
 [build-dependencies]
 

crates/re_renderer/src/file_resolver.rs

@@ -636,7 +636,7 @@ impl<Fs: FileSystem> FileResolver<Fs> {
 // TODO(cmc): might want an actual test using `RERUN_SHADER_PATH`
 #[cfg(test)]
 mod tests_file_resolver {
-    use crate::{FileSystem as _, MemFileSystem};
+    use crate::MemFileSystem;
     use unindent::unindent;
 
     use super::*;

crates/re_renderer/src/lib.rs

@@ -21,15 +21,30 @@ mod colormap;
 mod context;
 mod debug_label;
 mod depth_offset;
+mod draw_phases;
+mod file_resolver;
+mod file_server;
+mod file_system;
 mod global_bindings;
 mod line_strip_builder;
 mod point_cloud_builder;
 mod queuable_draw_data;
+mod rect;
 mod size;
 mod transform;
 mod wgpu_buffer_types;
 mod wgpu_resources;
 
+#[cfg(not(all(not(target_arch = "wasm32"), debug_assertions)))] // wasm or release builds
+#[rustfmt::skip] // it's auto-generated
+mod workspace_shaders;
+
+#[cfg(all(not(target_arch = "wasm32"), debug_assertions))] // native debug build
+mod error_tracker;
+
+// ---------------------------------------------------------------------------
+// Exports
+
 use allocator::GpuReadbackBuffer;
 pub use allocator::GpuReadbackIdentifier;
 
@@ -50,38 +65,24 @@ pub use transform::RectTransform;
 pub use view_builder::{AutoSizeConfig, ViewBuilder};
 pub use wgpu_resources::WgpuResourcePoolStatistics;
 
-mod draw_phases;
-pub(crate) use draw_phases::DrawPhase;
+use draw_phases::DrawPhase;
 pub use draw_phases::{
     OutlineConfig, OutlineMaskPreference, PickingLayerId, PickingLayerInstanceId,
     PickingLayerObjectId, PickingLayerProcessor, ScreenshotProcessor,
 };
 
-mod file_system;
 pub use self::file_system::{get_filesystem, FileSystem};
 #[allow(unused_imports)] // they can be handy from time to time
-pub(crate) use self::file_system::{MemFileSystem, OsFileSystem};
+use self::file_system::{MemFileSystem, OsFileSystem};
 
-mod file_resolver;
 pub use self::file_resolver::{
     new_recommended as new_recommended_file_resolver, FileResolver, ImportClause,
     RecommendedFileResolver, SearchPath,
 };
-
-mod file_server;
 pub use self::file_server::FileServer;
 
-mod rect;
-
-#[cfg(not(all(not(target_arch = "wasm32"), debug_assertions)))] // wasm or release builds
-#[rustfmt::skip] // it's auto-generated
-mod workspace_shaders;
-
-#[cfg(all(not(target_arch = "wasm32"), debug_assertions))] // native debug build
-mod error_tracker;
-
 // Re-export used color types.
-pub use ecolor::{Color32, Rgba};
+pub use ecolor::{Color32, Hsva, Rgba};
 
 // ---------------------------------------------------------------------------
 

crates/re_renderer/examples/2d.rs → crates/re_renderer_examples/2d.rs

@@ -1,5 +1,9 @@
-use ecolor::Hsva;
+//! Examples for using 2D rendering.
+//!
+//! On the left is a 2D view, on the right a 3D view of the same scene.
+
 use itertools::Itertools as _;
+use re_renderer::Hsva;
 
 use re_renderer::{
     renderer::{
@@ -26,7 +30,7 @@ impl framework::Example for Render2D {
 
     fn new(re_ctx: &re_renderer::RenderContext) -> Self {
         let rerun_logo =
-            image::load_from_memory(include_bytes!("../../re_ui/data/logo_dark_mode.png")).unwrap();
+            image::load_from_memory(include_bytes!("../re_ui/data/logo_dark_mode.png")).unwrap();
 
         let image_data = rerun_logo.as_rgba8().unwrap().to_vec();
 
@@ -303,7 +307,7 @@ impl framework::Example for Render2D {
                 view_builder.queue_draw(point_draw_data.clone());
                 view_builder.queue_draw(rectangle_draw_data.clone());
                 let command_buffer = view_builder
-                    .draw(re_ctx, ecolor::Rgba::TRANSPARENT)
+                    .draw(re_ctx, re_renderer::Rgba::TRANSPARENT)
                     .unwrap();
                 framework::ViewDrawResult {
                     view_builder,
@@ -345,7 +349,7 @@ impl framework::Example for Render2D {
                     .queue_draw(line_strip_draw_data)
                     .queue_draw(point_draw_data)
                     .queue_draw(rectangle_draw_data)
-                    .draw(re_ctx, ecolor::Rgba::TRANSPARENT)
+                    .draw(re_ctx, re_renderer::Rgba::TRANSPARENT)
                     .unwrap();
                 framework::ViewDrawResult {
                     view_builder,

crates/re_renderer_examples/Cargo.toml

@@ -0,0 +1,68 @@
+[package]
+name = "re_renderer_examples"
+description = "Examples for the re_renderer crate."
+version.workspace = true
+edition.workspace = true
+rust-version.workspace = true
+license.workspace = true
+publish = false
+
+[features]
+webgl = ["re_renderer/webgl"]
+
+
+[[bin]]
+name = "2d"
+path = "2d.rs"
+
+[[bin]]
+name = "depth_cloud"
+path = "depth_cloud.rs"
+
+[[bin]]
+name = "depth_offset"
+path = "depth_offset.rs"
+
+[[bin]]
+name = "multiview"
+path = "multiview.rs"
+
+[[bin]]
+name = "outlines"
+path = "outlines.rs"
+
+[[bin]]
+name = "picking"
+path = "picking.rs"
+
+
+[dependencies]
+re_log.workspace = true
+re_renderer = { workspace = true, features = ["import-obj", "import-gltf"] }
+
+ahash.workspace = true
+anyhow.workspace = true
+bytemuck.workspace = true
+glam.workspace = true
+image = { workspace = true, default-features = false, features = ["png"] }
+itertools.workspace = true
+log.workspace = true
+macaw.workspace = true
+pollster.workspace = true
+rand = { workspace = true, features = ["std", "std_rng"] }
+web-time.workspace = true
+wgpu.workspace = true
+winit.workspace = true
+zip = { workspace = true, default-features = false, features = ["deflate"] }
+
+[target.'cfg(target_arch = "wasm32")'.dependencies]
+console_error_panic_hook.workspace = true
+wasm-bindgen-futures.workspace = true
+web-sys = { workspace = true, features = [
+  "Location",
+  "Blob",
+  "RequestInit",
+  "RequestMode",
+  "Request",
+  "Response",
+] }

crates/re_renderer_examples/README.md

@@ -0,0 +1,20 @@
+Standalone examples for `re_renderer`
+-----------------------------------------------
+
+To get a list of all examples run:
+```
+cargo run -p re_renderer_examples --bin
+```
+
+E.g. to run the `multiview`` example run
+```
+cargo run -p re_renderer_examples --bin multiview
+```
+To run the same example on the web using WebGPU:
+```
+cargo run-wasm -p re_renderer_examples --bin multiview
+```
+To run the same example on the web using WebGL:
+```
+cargo run-wasm -p re_renderer_examples --bin multiview --features "webgl"
+```

crates/re_renderer/examples/depth_cloud.rs → crates/re_renderer_examples/depth_cloud.rs

@@ -130,7 +130,7 @@ impl RenderDepthClouds {
             .queue_draw(point_cloud_draw_data)
             .queue_draw(frame_draw_data)
             .queue_draw(image_draw_data)
-            .draw(re_ctx, ecolor::Rgba::TRANSPARENT)
+            .draw(re_ctx, re_renderer::Rgba::TRANSPARENT)
             .unwrap();
 
         framework::ViewDrawResult {
@@ -210,7 +210,7 @@ impl RenderDepthClouds {
             .queue_draw(depth_cloud_draw_data)
             .queue_draw(frame_draw_data)
             .queue_draw(image_draw_data)
-            .draw(re_ctx, ecolor::Rgba::TRANSPARENT)
+            .draw(re_ctx, re_renderer::Rgba::TRANSPARENT)
             .unwrap();
 
         framework::ViewDrawResult {

crates/re_renderer/examples/depth_offset.rs → crates/re_renderer_examples/depth_offset.rs

@@ -7,7 +7,7 @@
 //! Press arrow up/down to increase/decrease the distance of the camera to the z==0 plane in tandem with the scale of the rectangles.
 //! Press arrow left/right to increase/decrease the near plane distance.
 
-use ecolor::Hsva;
+use re_renderer::Hsva;
 use re_renderer::{
     renderer::{ColormappedTexture, RectangleDrawData, RectangleOptions, TexturedRect},
     view_builder::{self, Projection, ViewBuilder},
@@ -115,7 +115,7 @@ impl framework::Example for Render2D {
         );
         let command_buffer = view_builder
             .queue_draw(RectangleDrawData::new(re_ctx, &rectangles).unwrap())
-            .draw(re_ctx, ecolor::Rgba::TRANSPARENT)
+            .draw(re_ctx, re_renderer::Rgba::TRANSPARENT)
             .unwrap();
 
         vec![{

crates/re_renderer/examples/multiview.rs → crates/re_renderer_examples/multiview.rs

@@ -1,6 +1,7 @@
+//! Example with several independent views, using various primitives.
+
 use std::f32::consts::TAU;
 
-use ecolor::Hsva;
 use framework::Example;
 use glam::Vec3;
 use itertools::Itertools;
@@ -13,8 +14,8 @@ use re_renderer::{
         TestTriangleDrawData,
     },
     view_builder::{OrthographicCameraMode, Projection, TargetConfiguration, ViewBuilder},
-    Color32, GpuReadbackIdentifier, LineStripSeriesBuilder, PointCloudBuilder, RenderContext, Rgba,
-    ScreenshotProcessor, Size,
+    Color32, GpuReadbackIdentifier, Hsva, LineStripSeriesBuilder, PointCloudBuilder, RenderContext,
+    Rgba, ScreenshotProcessor, Size,
 };
 use winit::event::{ElementState, VirtualKeyCode};