Add camera functions (#47)

tychedelia · web-flow · commit f77cc47af391 · 2025-12-23T09:31:57.000-08:00
diff --git a/crates/processing_ffi/src/lib.rs b/crates/processing_ffi/src/lib.rs
@@ -524,3 +524,64 @@ pub unsafe extern "C" fn processing_image_readback(
         Ok(())
     });
 }
+
+#[unsafe(no_mangle)]
+pub extern "C" fn processing_mode_3d(window_id: u64) {
+    error::clear_error();
+    let window_entity = Entity::from_bits(window_id);
+    error::check(|| graphics_mode_3d(window_entity));
+}
+
+#[unsafe(no_mangle)]
+pub extern "C" fn processing_mode_2d(window_id: u64) {
+    error::clear_error();
+    let window_entity = Entity::from_bits(window_id);
+    error::check(|| graphics_mode_2d(window_entity));
+}
+
+#[unsafe(no_mangle)]
+pub extern "C" fn processing_camera_position(window_id: u64, x: f32, y: f32, z: f32) {
+    error::clear_error();
+    let window_entity = Entity::from_bits(window_id);
+    error::check(|| graphics_camera_position(window_entity, x, y, z));
+}
+
+#[unsafe(no_mangle)]
+pub extern "C" fn processing_camera_look_at(
+    window_id: u64,
+    target_x: f32,
+    target_y: f32,
+    target_z: f32,
+) {
+    error::clear_error();
+    let window_entity = Entity::from_bits(window_id);
+    error::check(|| graphics_camera_look_at(window_entity, target_x, target_y, target_z));
+}
+
+#[unsafe(no_mangle)]
+pub extern "C" fn processing_perspective(
+    window_id: u64,
+    fov: f32,
+    aspect: f32,
+    near: f32,
+    far: f32,
+) {
+    error::clear_error();
+    let window_entity = Entity::from_bits(window_id);
+    error::check(|| graphics_perspective(window_entity, fov, aspect, near, far));
+}
+
+#[unsafe(no_mangle)]
+pub extern "C" fn processing_ortho(
+    window_id: u64,
+    left: f32,
+    right: f32,
+    bottom: f32,
+    top: f32,
+    near: f32,
+    far: f32,
+) {
+    error::clear_error();
+    let window_entity = Entity::from_bits(window_id);
+    error::check(|| graphics_ortho(window_entity, left, right, bottom, top, near, far));
+}
diff --git a/crates/processing_pyo3/src/graphics.rs b/crates/processing_pyo3/src/graphics.rs
@@ -169,6 +169,43 @@ impl Graphics {
     pub fn end_draw(&self) -> PyResult<()> {
         graphics_end_draw(self.entity).map_err(|e| PyRuntimeError::new_err(format!("{e}")))
     }
+
+    pub fn mode_3d(&self) -> PyResult<()> {
+        graphics_mode_3d(self.entity).map_err(|e| PyRuntimeError::new_err(format!("{e}")))
+    }
+
+    pub fn mode_2d(&self) -> PyResult<()> {
+        graphics_mode_2d(self.entity).map_err(|e| PyRuntimeError::new_err(format!("{e}")))
+    }
+
+    pub fn camera_position(&self, x: f32, y: f32, z: f32) -> PyResult<()> {
+        graphics_camera_position(self.entity, x, y, z)
+            .map_err(|e| PyRuntimeError::new_err(format!("{e}")))
+    }
+
+    pub fn camera_look_at(&self, target_x: f32, target_y: f32, target_z: f32) -> PyResult<()> {
+        graphics_camera_look_at(self.entity, target_x, target_y, target_z)
+            .map_err(|e| PyRuntimeError::new_err(format!("{e}")))
+    }
+
+    pub fn perspective(&self, fov: f32, aspect: f32, near: f32, far: f32) -> PyResult<()> {
+        graphics_perspective(self.entity, fov, aspect, near, far)
+            .map_err(|e| PyRuntimeError::new_err(format!("{e}")))
+    }
+
+    #[allow(clippy::too_many_arguments)]
+    pub fn ortho(
+        &self,
+        left: f32,
+        right: f32,
+        bottom: f32,
+        top: f32,
+        near: f32,
+        far: f32,
+    ) -> PyResult<()> {
+        graphics_ortho(self.entity, left, right, bottom, top, near, far)
+            .map_err(|e| PyRuntimeError::new_err(format!("{e}")))
+    }
 }
 
 // TODO: a real color type. or color parser? idk. color is confusing. let's think
diff --git a/crates/processing_render/src/graphics.rs b/crates/processing_render/src/graphics.rs
@@ -275,6 +275,169 @@ pub fn resize(
     }
 }
 
+pub fn mode_3d(
+    In(entity): In<Entity>,
+    mut projections: Query<&mut Projection>,
+    mut transforms: Query<&mut Transform>,
+    sizes: Query<&SurfaceSize>,
+) -> Result<()> {
+    let SurfaceSize(width, height) = sizes
+        .get(entity)
+        .map_err(|_| ProcessingError::GraphicsNotFound)?;
+
+    let width = *width as f32;
+    let height = *height as f32;
+
+    let fov = std::f32::consts::PI / 3.0; // 60 degrees
+    let aspect = width / height;
+    let camera_z = (height / 2.0) / (fov / 2.0).tan();
+    let near = camera_z / 10.0;
+    let far = camera_z * 10.0;
+
+    let mut projection = projections
+        .get_mut(entity)
+        .map_err(|_| ProcessingError::GraphicsNotFound)?;
+
+    *projection = Projection::Perspective(PerspectiveProjection {
+        fov,
+        aspect_ratio: aspect,
+        near,
+        far,
+    });
+
+    let mut transform = transforms
+        .get_mut(entity)
+        .map_err(|_| ProcessingError::GraphicsNotFound)?;
+
+    *transform = Transform::from_xyz(0.0, 0.0, camera_z).looking_at(Vec3::ZERO, Vec3::Y);
+
+    Ok(())
+}
+
+pub fn mode_2d(
+    In(entity): In<Entity>,
+    mut projections: Query<&mut Projection>,
+    mut transforms: Query<&mut Transform>,
+    sizes: Query<&SurfaceSize>,
+) -> Result<()> {
+    let SurfaceSize(width, height) = sizes
+        .get(entity)
+        .map_err(|_| ProcessingError::GraphicsNotFound)?;
+
+    let mut projection = projections
+        .get_mut(entity)
+        .map_err(|_| ProcessingError::GraphicsNotFound)?;
+
+    *projection = Projection::custom(ProcessingProjection {
+        width: *width as f32,
+        height: *height as f32,
+        near: 0.0,
+        far: 1000.0,
+    });
+
+    let mut transform = transforms
+        .get_mut(entity)
+        .map_err(|_| ProcessingError::GraphicsNotFound)?;
+
+    *transform = Transform::from_xyz(0.0, 0.0, 999.9);
+
+    Ok(())
+}
+
+pub fn camera_position(
+    In((entity, x, y, z)): In<(Entity, f32, f32, f32)>,
+    mut transforms: Query<&mut Transform>,
+) -> Result<()> {
+    let mut transform = transforms
+        .get_mut(entity)
+        .map_err(|_| ProcessingError::GraphicsNotFound)?;
+
+    transform.translation = Vec3::new(x, y, z);
+
+    Ok(())
+}
+
+pub fn camera_look_at(
+    In((entity, target_x, target_y, target_z)): In<(Entity, f32, f32, f32)>,
+    mut transforms: Query<&mut Transform>,
+) -> Result<()> {
+    let mut transform = transforms
+        .get_mut(entity)
+        .map_err(|_| ProcessingError::GraphicsNotFound)?;
+
+    // TODO: allow specifying up vector?
+    // does anyone actually use anything other than Vec3::Y here?
+    let target = Vec3::new(target_x, target_y, target_z);
+    transform.look_at(target, Vec3::Y);
+
+    Ok(())
+}
+
+pub fn perspective(
+    In((
+        entity,
+        PerspectiveProjection {
+            fov,
+            aspect_ratio,
+            near,
+            far,
+        },
+    )): In<(Entity, PerspectiveProjection)>,
+    mut projections: Query<&mut Projection>,
+) -> Result<()> {
+    let mut projection = projections
+        .get_mut(entity)
+        .map_err(|_| ProcessingError::GraphicsNotFound)?;
+
+    *projection = Projection::Perspective(PerspectiveProjection {
+        fov,
+        aspect_ratio,
+        near,
+        far,
+    });
+
+    Ok(())
+}
+
+pub struct OrthoArgs {
+    pub left: f32,
+    pub right: f32,
+    pub bottom: f32,
+    pub top: f32,
+    pub near: f32,
+    pub far: f32,
+}
+
+pub fn ortho(
+    In((
+        entity,
+        OrthoArgs {
+            left,
+            right,
+            bottom,
+            top,
+            near,
+            far,
+        },
+    )): In<(Entity, OrthoArgs)>,
+    mut projections: Query<&mut Projection>,
+) -> Result<()> {
+    let mut projection = projections
+        .get_mut(entity)
+        .map_err(|_| ProcessingError::GraphicsNotFound)?;
+
+    // we need a custom projection to support processing's coordinate system
+    // but this is in effect an orthographic projection with the given bounds
+    *projection = Projection::custom(ProcessingProjection {
+        width: right - left,
+        height: top - bottom,
+        near,
+        far,
+    });
+
+    Ok(())
+}
+
 pub fn destroy(
     In(entity): In<Entity>,
     mut commands: Commands,
diff --git a/crates/processing_render/src/lib.rs b/crates/processing_render/src/lib.rs
@@ -17,6 +17,7 @@ use bevy::{
 use render::{activate_cameras, clear_transient_meshes, flush_draw_commands};
 use tracing::debug;
 
+use crate::graphics::flush;
 use crate::{
     graphics::GraphicsPlugin, image::ImagePlugin, render::command::DrawCommand,
     surface::SurfacePlugin,
@@ -445,6 +446,112 @@ pub fn graphics_record_command(graphics_entity: Entity, cmd: DrawCommand) -> err
     })
 }
 
+pub fn graphics_mode_3d(graphics_entity: Entity) -> error::Result<()> {
+    app_mut(|app| {
+        flush(app, graphics_entity)?;
+        app.world_mut()
+            .run_system_cached_with(graphics::mode_3d, graphics_entity)
+            .unwrap()
+    })
+}
+
+pub fn graphics_mode_2d(graphics_entity: Entity) -> error::Result<()> {
+    app_mut(|app| {
+        flush(app, graphics_entity)?;
+        app.world_mut()
+            .run_system_cached_with(graphics::mode_2d, graphics_entity)
+            .unwrap()
+    })
+}
+
+pub fn graphics_camera_position(
+    graphics_entity: Entity,
+    x: f32,
+    y: f32,
+    z: f32,
+) -> error::Result<()> {
+    app_mut(|app| {
+        flush(app, graphics_entity)?;
+        app.world_mut()
+            .run_system_cached_with(graphics::camera_position, (graphics_entity, x, y, z))
+            .unwrap()
+    })
+}
+
+pub fn graphics_camera_look_at(
+    graphics_entity: Entity,
+    target_x: f32,
+    target_y: f32,
+    target_z: f32,
+) -> error::Result<()> {
+    app_mut(|app| {
+        flush(app, graphics_entity)?;
+        app.world_mut()
+            .run_system_cached_with(
+                graphics::camera_look_at,
+                (graphics_entity, target_x, target_y, target_z),
+            )
+            .unwrap()
+    })
+}
+
+pub fn graphics_perspective(
+    graphics_entity: Entity,
+    fov: f32,
+    aspect_ratio: f32,
+    near: f32,
+    far: f32,
+) -> error::Result<()> {
+    app_mut(|app| {
+        flush(app, graphics_entity)?;
+        app.world_mut()
+            .run_system_cached_with(
+                graphics::perspective,
+                (
+                    graphics_entity,
+                    PerspectiveProjection {
+                        fov,
+                        aspect_ratio,
+                        near,
+                        far,
+                    },
+                ),
+            )
+            .unwrap()
+    })
+}
+
+#[allow(clippy::too_many_arguments)]
+pub fn graphics_ortho(
+    graphics_entity: Entity,
+    left: f32,
+    right: f32,
+    bottom: f32,
+    top: f32,
+    near: f32,
+    far: f32,
+) -> error::Result<()> {
+    app_mut(|app| {
+        flush(app, graphics_entity)?;
+        app.world_mut()
+            .run_system_cached_with(
+                graphics::ortho,
+                (
+                    graphics_entity,
+                    graphics::OrthoArgs {
+                        left,
+                        right,
+                        bottom,
+                        top,
+                        near,
+                        far,
+                    },
+                ),
+            )
+            .unwrap()
+    })
+}
+
 /// Create a new image with given size and data.
 pub fn image_create(
     size: Extent3d,
