first commit

src/scene/transform.rs

@@ -0,0 +1,65 @@
+use acadrust::types::{Transform, Vector3};
+use glam::Vec3;
+
+use crate::command::EntityTransform;
+
+#[inline]
+fn to_v3(v: Vec3) -> Vector3 {
+    Vector3::new(v.x as f64, v.y as f64, v.z as f64)
+}
+
+pub fn apply_standard_transform<T>(entity: &mut T, center: Vec3, angle_rad: f32)
+where
+    T: acadrust::Entity,
+{
+    let z_axis = Vector3::new(0.0, 0.0, 1.0);
+    let t = Transform::from_translation(to_v3(-center))
+        .then(&Transform::from_rotation(z_axis, angle_rad as f64))
+        .then(&Transform::from_translation(to_v3(center)));
+    entity.apply_transform(&t);
+}
+
+pub fn apply_standard_scale<T>(entity: &mut T, center: Vec3, factor: f32)
+where
+    T: acadrust::Entity,
+{
+    let s = factor as f64;
+    let t = Transform::from_scaling_with_origin(Vector3::new(s, s, s), to_v3(center));
+    entity.apply_transform(&t);
+}
+
+pub fn apply_standard_entity_transform<T, F>(entity: &mut T, t: &EntityTransform, mirror: F)
+where
+    T: acadrust::Entity,
+    F: FnOnce(&mut T, Vec3, Vec3),
+{
+    match t {
+        EntityTransform::Translate(d) => entity.translate(to_v3(*d)),
+        EntityTransform::Rotate { center, angle_rad } => {
+            apply_standard_transform(entity, *center, *angle_rad)
+        }
+        EntityTransform::Scale { center, factor } => apply_standard_scale(entity, *center, *factor),
+        EntityTransform::Mirror { p1, p2 } => mirror(entity, *p1, *p2),
+    }
+}
+
+pub fn reflect_xy_point(x: &mut f64, y: &mut f64, p1: Vec3, p2: Vec3) {
+    let ax = (p2.x - p1.x) as f64;
+    let ay = (p2.y - p1.y) as f64;
+    let len2 = ax * ax + ay * ay;
+    if len2 < 1e-12 {
+        return;
+    }
+    let rx = *x - p1.x as f64;
+    let ry = *y - p1.y as f64;
+    let dot = rx * ax + ry * ay;
+    let mx = 2.0 * dot * ax / len2 - rx;
+    let my = 2.0 * dot * ay / len2 - ry;
+    *x = p1.x as f64 + mx;
+    *y = p1.y as f64 + my;
+}
+
+pub fn mirror_xy_line(line: &mut acadrust::entities::Line, p1: Vec3, p2: Vec3) {
+    reflect_xy_point(&mut line.start.x, &mut line.start.y, p1, p2);
+    reflect_xy_point(&mut line.end.x, &mut line.end.y, p1, p2);
+}