WiP

.gitignore

@@ -1,5 +1,17 @@
-# Rust
-/target
+# Generated by Cargo
+# will have compiled files and executables
+debug/
+target/
+
+# Remove Cargo.lock from gitignore if creating an executable, leave it for libraries
+# More information here https://doc.rust-lang.org/cargo/guide/cargo-toml-vs-cargo-lock.html
+Cargo.lock
+
+# These are backup files generated by rustfmt
+**/*.rs.bk
+
+# MSVC Windows builds of rustc generate these, which store debugging information
+*.pdb
 
 # Visual Studio Code
 

Cargo.lock

@@ -188,6 +188,7 @@ version = "0.9.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3654d60973fcde065efcfe0c9066c81a76987d28c45233998b2ccdc581dcd914"
 dependencies = [
+ "bevy_dylib",
  "bevy_internal",
 ]
 
@@ -328,6 +329,15 @@ dependencies = [
  "bevy_utils",
 ]
 
+[[package]]
+name = "bevy_dylib"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0d52cc91729fc26ea7038ad49ed773e0577688e328b6f7466be3d5070b45cea9"
+dependencies = [
+ "bevy_internal",
+]
+
 [[package]]
 name = "bevy_ecs"
 version = "0.9.0"

Cargo.toml

@@ -6,5 +6,6 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-bevy = "0.9.0"
+# bevy = "0.9.0"
+bevy = { version = "0.9.0", features = ["dynamic"] }
 # vrpn = "0.1.0" # not compatible with 2021

README.md

@@ -14,6 +14,7 @@ Ideas are derived from a software written several years ago called VisionSpace.
 
 # TODO
 
+* [ ] build a system that updates a cameras frustum (w/ offaxis)
 * [ ] multiple cameras
 * [ ] custom projection matrices (https://bevy-cheatbook.github.io/cookbook/custom-projection.html)
 * [ ] render to texture

src/main.rs

@@ -26,7 +26,7 @@ fn main() {
         }))
         // .add_plugins(DefaultPlugins)
         .add_plugin(scene::BuildScenePlugin)
-        .add_startup_system(offaxis::camera_setup)
+        // .add_startup_system(offaxis::camera_setup)
         .add_system(bevy::window::close_on_esc)
         .add_system(cycle_msaa)
         // .add_system_to_stage(

src/scene.rs

@@ -1,11 +1,11 @@
-use bevy::prelude::*;
+use bevy::{prelude::*, math::bool};
 
 pub struct BuildScenePlugin;
 
 impl Plugin for BuildScenePlugin {
     fn build(&self, app: &mut App) {
         app.add_startup_system(build_scene) // actual scene
-        .add_system(print_positions); // debugging
+            .add_system(print_positions); // debugging
     }
 }
 
@@ -13,16 +13,98 @@ impl Plugin for BuildScenePlugin {
 struct Person;
 
 #[derive(Component)]
-pub struct Position { x: f32, y: f32 }
+pub struct Position {
+    x: f32,
+    y: f32,
+}
+
+#[derive(Component)]
+pub struct ProjectionScreen {
+    bottom_left: Vec3,
+    bottom_right: Vec3,
+    top_left: Vec3,
+    top_right: Vec3,
+
+    dir_right: Vec3,
+    dir_up: Vec3,
+    dir_normal: Vec3,
+
+    matrix: Mat4
+
+}
+
+fn compute_offaxis_frustum (
+    projectionScreen: ProjectionScreen,
+    eyePos: Vec3,
+    mut camera: Camera3dBundle,
+    clampNearPlane: bool,
+)
+{
+    let pa = projectionScreen.bottom_left;
+    let pb = projectionScreen.bottom_right;
+    let pc = projectionScreen.top_left;
+    let pd = projectionScreen.top_right;
+
+    let vu = projectionScreen.dir_up;
+    let vr = projectionScreen.dir_right;
+    let vn = projectionScreen.dir_normal;
+
+    let m = projectionScreen.matrix;
+
+    let va = pa - eyePos;
+    let vb = pb - eyePos;
+    let vc = pc - eyePos;
+    let vd = pd - eyePos;
+
+    let viewDir = eyePos + va + vb + vc + vd;
+
+    let d = -va.dot(vn);
+
+    if (clampNearPlane) {
+        // camera.frustum.planes[4]. // should be near
+    }
+}
+
+pub fn build_scene(
+    mut commands: Commands,
+    mut meshes: ResMut<Assets<Mesh>>,
+    mut materials: ResMut<Assets<StandardMaterial>>,
+) {
+    // plane
+    commands.spawn(PbrBundle {
+        mesh: meshes.add(Mesh::from(shape::Plane { size: 5.0 })),
+        material: materials.add(Color::rgb(0.3, 0.5, 0.3).into()),
+        ..default()
+    });
+    // cube
+    commands.spawn(PbrBundle {
+        mesh: meshes.add(Mesh::from(shape::Cube { size: 1.0 })),
+        material: materials.add(Color::rgb(0.8, 0.7, 0.6).into()),
+        transform: Transform::from_xyz(0.0, 0.5, 0.0),
+        ..default()
+    });
+    // light
+    commands.spawn(PointLightBundle {
+        point_light: PointLight {
+            intensity: 1500.0,
+            shadows_enabled: true,
+            ..default()
+        },
+        transform: Transform::from_xyz(4.0, 8.0, 4.0),
+        ..default()
+    });
 
 
-pub fn build_scene(mut commands: Commands)  {
-    commands.spawn((
-        Person,
-        Position { x: 10.0, y: 10.0 }
+    // camera
 
-    )        
-    );
+    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()
     // .insert(Person)
     // .insert(Position { x: 10.0, y: 10.0 } );
@@ -34,11 +116,9 @@ pub fn build_scene(mut commands: Commands)  {
     // });
 }
 
-pub fn print_positions(query : Query<&Position>) {
+pub fn print_positions(query: Query<&Position>) {
     for _position in query.iter() {
-
         _ = 33;
         // println!("position {:?} {:?}", position.x, position.y)
-    
     }
 }