first step done: we have a custom and updatable matrix

src/scene.rs

@@ -1,4 +1,7 @@
-use bevy::{prelude::*, math::bool};
+use bevy::{prelude::*, math::bool, render::primitives::Frustum};
+use rand::prelude::*;
+use bevy::render::primitives::Plane;
+
 
 pub struct BuildScenePlugin;
 
@@ -33,7 +36,15 @@ pub struct ProjectionScreen {
 
 }
 
-fn compute_offaxis_frustum (
+
+
+fn generalized_projection_stereo(eyePos : Vec3)
+{
+
+}
+
+
+fn generalized_projection (
     projectionScreen: ProjectionScreen,
     eyePos: Vec3,
     mut camera: Camera3dBundle,
@@ -49,7 +60,9 @@ fn compute_offaxis_frustum (
     let vr = projectionScreen.dir_right;
     let vn = projectionScreen.dir_normal;
 
-    let m = projectionScreen.matrix;
+    // let m = projectionScreen.matrix;
+
+    //let m = Mat4::from_cols(vu., y_axis, z_axis, w_axis)
 
     let va = pa - eyePos;
     let vb = pb - eyePos;
@@ -60,7 +73,9 @@ fn compute_offaxis_frustum (
 
     let d = -va.dot(vn);
 
-    if (clampNearPlane) {
+
+    if clampNearPlane {
+        _ = 33;
         // camera.frustum.planes[4]. // should be near
     }
 }
@@ -99,12 +114,15 @@ pub fn build_scene(
 
     let mut cam = Camera3dBundle {
         transform: Transform::from_xyz(-2.0, 2.5, 5.0).looking_at(Vec3::ZERO, Vec3::Y),
+
         ..default()
     };
 
-    commands.spawn(cam);
 
-    commands.spawn((Person, Position { x: 10.0, y: 10.0 }));
+
+    // commands.spawn(cam);
+
+    // commands.spawn((Person, Position { x: 10.0, y: 10.0 }));
     // commands.spawn()
     // .insert(Person)
     // .insert(Position { x: 10.0, y: 10.0 } );
@@ -116,9 +134,52 @@ pub fn build_scene(
     // });
 }
 
+
+
+pub fn modify_frustum(mut query: Query<&Frustum>)
+{
+    let mut rng = rand::thread_rng();
+
+    for mut q in query.iter() {
+
+        for mut p in q.planes {
+
+            println!("{:?}",p);
+
+            let mut n = p.normal_d();
+
+            n.w += rng.gen::<f32>();
+
+            p = Plane::new(n);
+
+            println!("{:?}",p);
+
+
+
+            // p.normal_d() += rng.gen();
+        }
+
+        // println!("{:?}",q.frustum.planes.len()); 
+    }
+}
+
+
+pub fn modify_projection(mut query: Query<&Projection>)
+{
+    let mut rng = rand::thread_rng();
+
+    for mut q in query.iter() {
+        
+        print!("{:?}",q);
+    }
+}
+
 pub fn print_positions(query: Query<&Position>) {
     for _position in query.iter() {
         _ = 33;
         // println!("position {:?} {:?}", position.x, position.y)
     }
 }
+
+// Problem with off-axis
+// projection 2401, 240