background_image example in python

Cargo.toml

@@ -11,6 +11,7 @@ workspace = true
 default = ["wayland"]
 wayland = ["processing_render/wayland"]
 x11 = ["processing_render/x11"]
+python = ["processing_render/python"]
 
 [workspace]
 resolver = "3"

crates/processing_ffi/src/lib.rs

@@ -17,7 +17,7 @@ mod error;
 #[unsafe(no_mangle)]
 pub extern "C" fn processing_init() {
     error::clear_error();
-    error::check(init);
+    error::check(|| init(None));
 }
 
 /// Create a WebGPU surface from a macOS NSWindow handle.

crates/processing_pyo3/Cargo.toml

@@ -17,7 +17,7 @@ x11 = ["processing/x11"]
 
 [dependencies]
 pyo3 = "0.27.0"
-processing = { workspace = true }
+processing = { workspace = true, features = ["python"] }
 bevy = { workspace = true }
 glfw = { version = "0.60.0"}
 

crates/processing_pyo3/examples/background_image.py

@@ -0,0 +1,12 @@
+from processing import *
+
+def setup():
+    size(800, 600)
+
+def draw():
+    background(220)
+    image("images/logo.png")
+
+
+# TODO: this should happen implicitly on module load somehow
+run()

crates/processing_pyo3/src/graphics.rs

@@ -38,11 +38,13 @@ impl Drop for Graphics {
 #[pymethods]
 impl Graphics {
     #[new]
-    pub fn new(width: u32, height: u32) -> PyResult<Self> {
+    pub fn new(width: u32, height: u32, asset_path: &str) -> PyResult<Self> {
         let glfw_ctx =
             GlfwContext::new(width, height).map_err(|e| PyRuntimeError::new_err(format!("{e}")))?;
 
-        init().map_err(|e| PyRuntimeError::new_err(format!("{e}")))?;
+        let mut config = Config::new();
+        config.set(ConfigKey::AssetRootPath, asset_path.to_string());
+        init(Some(config)).map_err(|e| PyRuntimeError::new_err(format!("{e}")))?;
 
         let surface = glfw_ctx
             .create_surface(width, height, 1.0)
@@ -122,6 +124,12 @@ impl Graphics {
         .map_err(|e| PyRuntimeError::new_err(format!("{e}")))
     }
 
+    pub fn image(&self, file: &str) -> PyResult<()> {
+        let image = image_load(file).unwrap();
+        graphics_record_command(self.entity, DrawCommand::BackgroundImage(image))
+            .map_err(|e| PyRuntimeError::new_err(format!("{e}")))
+    }
+
     pub fn push_matrix(&self) -> PyResult<()> {
         graphics_record_command(self.entity, DrawCommand::PushMatrix)
             .map_err(|e| PyRuntimeError::new_err(format!("{e}")))

crates/processing_pyo3/src/lib.rs

@@ -7,7 +7,7 @@
 //! receiver.
 //!
 //! To allow Python users to create a similar experience, we provide module-level
-//! functions that forward to a singleton Graphics object bepub(crate) pub(crate) hind the scenes.
+//! functions that forward to a singleton Graphics object pub(crate) behind the scenes.
 mod glfw;
 mod graphics;
 
@@ -16,23 +16,37 @@ use pyo3::{exceptions::PyRuntimeError, prelude::*};
 
 #[pymodule]
 fn processing(m: &Bound<'_, PyModule>) -> PyResult<()> {
-    m.add_class::<Graphics>()?;
-    m.add_function(wrap_pyfunction!(size, m)?)?;
-    m.add_function(wrap_pyfunction!(run, m)?)?;
-    m.add_function(wrap_pyfunction!(background, m)?)?;
-    m.add_function(wrap_pyfunction!(fill, m)?)?;
-    m.add_function(wrap_pyfunction!(no_fill, m)?)?;
-    m.add_function(wrap_pyfunction!(stroke, m)?)?;
-    m.add_function(wrap_pyfunction!(no_stroke, m)?)?;
-    m.add_function(wrap_pyfunction!(stroke_weight, m)?)?;
-    m.add_function(wrap_pyfunction!(rect, m)?)?;
-    Ok(())
+    Python::attach(|py| {
+        let sys = PyModule::import(py, "sys")?;
+        let argv: Vec<String> = sys.getattr("argv")?.extract()?;
+        let filename: &str = argv[0].as_str();
+        let os = PyModule::import(py, "os")?;
+        let path = os.getattr("path")?;
+        let dirname = path.getattr("dirname")?.call1((filename,))?;
+        let abspath = path.getattr("abspath")?.call1((dirname,))?;
+        let abspath = path.getattr("join")?.call1((abspath, "assets"))?;
+
+        m.add("_root_dir", abspath)?;
+        m.add_class::<Graphics>()?;
+        m.add_function(wrap_pyfunction!(size, m)?)?;
+        m.add_function(wrap_pyfunction!(run, m)?)?;
+        m.add_function(wrap_pyfunction!(background, m)?)?;
+        m.add_function(wrap_pyfunction!(fill, m)?)?;
+        m.add_function(wrap_pyfunction!(no_fill, m)?)?;
+        m.add_function(wrap_pyfunction!(stroke, m)?)?;
+        m.add_function(wrap_pyfunction!(no_stroke, m)?)?;
+        m.add_function(wrap_pyfunction!(stroke_weight, m)?)?;
+        m.add_function(wrap_pyfunction!(rect, m)?)?;
+        m.add_function(wrap_pyfunction!(image, m)?)?;
+        Ok(())
+    })
 }
 
 #[pyfunction]
 #[pyo3(pass_module)]
 fn size(module: &Bound<'_, PyModule>, width: u32, height: u32) -> PyResult<()> {
-    let graphics = Graphics::new(width, height)?;
+    let asset_path: String = module.getattr("_root_dir")?.extract()?;
+    let graphics = Graphics::new(width, height, asset_path.as_str())?;
     module.setattr("_graphics", graphics)?;
     Ok(())
 }
@@ -122,3 +136,9 @@ fn rect(
 ) -> PyResult<()> {
     get_graphics(module)?.rect(x, y, w, h, tl, tr, br, bl)
 }
+
+#[pyfunction]
+#[pyo3(pass_module, signature = (image_file))]
+fn image(module: &Bound<'_, PyModule>, image_file: &str) -> PyResult<()> {
+    get_graphics(module)?.image(image_file)
+}

crates/processing_render/Cargo.toml

@@ -10,6 +10,7 @@ workspace = true
 default = []
 wayland = ["bevy/wayland"]
 x11 = ["bevy/x11"]
+python = []
 
 [dependencies]
 bevy = { workspace = true }
@@ -32,4 +33,4 @@ windows = { version = "0.58", features = ["Win32_Foundation", "Win32_System_Libr
 wasm-bindgen = "0.2"
 wasm-bindgen-futures = "0.4"
 js-sys = "0.3"
-web-sys = { version = "0.3", features = ["Window", "Document", "HtmlCanvasElement"] }
+web-sys = { version = "0.3", features = ["Window", "Document", "HtmlCanvasElement"] }

crates/processing_render/src/config.rs

@@ -0,0 +1,32 @@
+//! Options object for configuring various aspects of libprocessing.
+//!
+//! To add a new Config just add a new enum with associated value
+
+use std::collections::HashMap;
+
+#[derive(Hash, Eq, PartialEq)]
+pub enum ConfigKey {
+    AssetRootPath,
+}
+// TODO: Consider Box<dyn Any> instead of String
+pub type ConfigMap = HashMap<ConfigKey, String>;
+pub struct Config {
+    map: ConfigMap,
+}
+
+impl Config {
+    pub fn new() -> Self {
+        // TODO consider defaults
+        Config {
+            map: ConfigMap::new(),
+        }
+    }
+
+    pub fn get(&self, k: ConfigKey) -> Option<&String> {
+        self.map.get(&k)
+    }
+
+    pub fn set(&mut self, k: ConfigKey, v: String) {
+        self.map.insert(k, v);
+    }
+}

crates/processing_render/src/image.rs

@@ -3,6 +3,8 @@
 //! It can be created from raw pixel data, loaded from disk, resized, and read back to CPU memory.
 use std::path::PathBuf;
 
+#[cfg(feature = "python")]
+use bevy::asset::{AssetPath, io::AssetSourceId};
 use bevy::{
     asset::{
         LoadState, RenderAssetUsages, handle_internal_asset_events, io::embedded::GetAssetServer,
@@ -138,6 +140,9 @@ pub fn from_handle(
 }
 
 pub fn load(In(path): In<PathBuf>, world: &mut World) -> Result<Entity> {
+    #[cfg(feature = "python")]
+    let path = AssetPath::from_path_buf(path).with_source(AssetSourceId::from("assets_directory"));
+
     let handle: Handle<bevy::image::Image> = world.get_asset_server().load(path);
     while let LoadState::Loading = world.get_asset_server().load_state(&handle) {
         world.run_system_once(handle_internal_asset_events).unwrap();

crates/processing_render/src/lib.rs

@@ -1,3 +1,4 @@
+pub mod config;
 pub mod error;
 mod graphics;
 pub mod image;
@@ -6,6 +7,10 @@ mod surface;
 
 use std::{cell::RefCell, num::NonZero, path::PathBuf, sync::OnceLock};
 
+use config::*;
+
+#[cfg(feature = "python")]
+use bevy::asset::io::AssetSourceBuilder;
 #[cfg(not(target_arch = "wasm32"))]
 use bevy::log::tracing_subscriber;
 use bevy::{
@@ -202,7 +207,7 @@ pub fn surface_resize(graphics_entity: Entity, width: u32, height: u32) -> error
     })
 }
 
-fn create_app() -> App {
+fn create_app(_config: Config) -> App {
     let mut app = App::new();
 
     #[cfg(not(target_arch = "wasm32"))]
@@ -227,6 +232,15 @@ fn create_app() -> App {
             ..default()
         });
 
+    #[cfg(feature = "python")]
+    {
+        let asset_path = _config.get(ConfigKey::AssetRootPath).unwrap();
+        app.register_asset_source(
+            "assets_directory",
+            AssetSourceBuilder::platform_default(asset_path, None),
+        );
+    }
+
     app.add_plugins(plugins);
     app.add_plugins((ImagePlugin, GraphicsPlugin, SurfacePlugin));
     app.add_systems(First, (clear_transient_meshes, activate_cameras))
@@ -257,14 +271,17 @@ fn set_app(app: App) {
 
 /// Initialize the app, if not already initialized. Must be called from the main thread and cannot
 /// be called concurrently from multiple threads.
+/// asset_path is Optional because only python needs to use it.
 #[cfg(not(target_arch = "wasm32"))]
-pub fn init() -> error::Result<()> {
+pub fn init(config: Option<Config>) -> error::Result<()> {
+    let config = config.unwrap_or_else(|| Config::new());
+
     setup_tracing()?;
     if is_already_init()? {
         return Ok(());
     }
 
-    let mut app = create_app();
+    let mut app = create_app(config);
     app.finish();
     app.cleanup();
     set_app(app);

examples/background_image.rs

@@ -19,7 +19,7 @@ fn main() {
 
 fn sketch() -> error::Result<()> {
     let mut glfw_ctx = GlfwContext::new(400, 400)?;
-    init()?;
+    init(None)?;
 
     let width = 400;
     let height = 400;

examples/rectangle.rs

@@ -19,7 +19,7 @@ fn main() {
 
 fn sketch() -> error::Result<()> {
     let mut glfw_ctx = GlfwContext::new(400, 400)?;
-    init()?;
+    init(None)?;
 
     let width = 400;
     let height = 400;

examples/transforms.rs

@@ -13,7 +13,7 @@ fn main() {
 
 fn sketch() -> error::Result<()> {
     let mut glfw_ctx = GlfwContext::new(400, 400)?;
-    init()?;
+    init(None)?;
 
     let surface = glfw_ctx.create_surface(400, 400, 1.0)?;
     let graphics = graphics_create(surface, 400, 400)?;

examples/update_pixels.rs

@@ -19,7 +19,7 @@ fn main() {
 
 fn sketch() -> error::Result<()> {
     let mut glfw_ctx = GlfwContext::new(100, 100)?;
-    init()?;
+    init(None)?;
 
     let width = 100;
     let height = 100;

src/prelude.rs

@@ -1,2 +1,2 @@
 pub use bevy::prelude::default;
-pub use processing_render::{render::command::DrawCommand, *};
+pub use processing_render::{config::*, render::command::DrawCommand, *};