Render volume of DEM instead of cube

Instead of a +/-1 cube, draw the AABB of the DEM

src/app/dem_renderer.rs

@@ -22,6 +22,12 @@ struct Vertex {
     position: [f32; 4],
 }
 
+impl Vertex {
+    fn new(x:f32, y:f32, z:f32) -> Self {
+        Self { position: [x, y, z, 1.0] }
+    }
+}
+
 struct Uniforms {
     projection_matrix: glam::Mat4,
     view_matrix: glam::Mat4,
@@ -31,7 +37,7 @@ struct Uniforms {
 impl Uniforms {
     fn new(device: &wgpu::Device, aspect_ratio: f32) -> Self {
         let projection_matrix =
-            glam::Mat4::perspective_rh(std::f32::consts::FRAC_PI_4, aspect_ratio, 1.0, 10.0);
+            glam::Mat4::perspective_rh(std::f32::consts::FRAC_PI_4, aspect_ratio, 1.0, 10000.0);
         let view_matrix = glam::Mat4::look_at_rh(glam::Vec3::ZERO, glam::Vec3::ZERO, glam::Vec3::Z);
         let camera_matrix = projection_matrix * view_matrix;
         let camera_matrix_ref: &[f32; 16] = camera_matrix.as_ref();
@@ -47,8 +53,8 @@ impl Uniforms {
         }
     }
 
-    fn set_camera_position(&mut self, position: glam::Vec3) {
+    fn set_camera_position(&mut self, camera_position: glam::Vec3, camera_look_at: glam::Vec3) {
-        self.view_matrix = glam::Mat4::look_at_rh(position, glam::Vec3::ZERO, glam::Vec3::Z);
+        self.view_matrix = glam::Mat4::look_at_rh(camera_position, camera_look_at, glam::Vec3::Z);
     }
 
     fn set_aspect_ratio(&mut self, ratio: f32) {
@@ -73,7 +79,7 @@ impl DemRenderer {
         device: &wgpu::Device,
         surface_config: &wgpu::SurfaceConfiguration,
     ) -> Self {
-        let (vertex_data, index_data) = create_vertices();
+        let (vertex_data, index_data) = create_vertices(&source);
 
         let vertex_buffer = device.create_buffer_init(&wgpu::util::BufferInitDescriptor {
             label: Some("DemRenderer Vertex Buffer"),
@@ -190,8 +196,13 @@ impl DemRenderer {
         let mut encoder = device.create_command_encoder(&wgpu::CommandEncoderDescriptor {
             label: Some("DemRendererCommandEncoder"),
         });
-        self.uniforms
+        self.uniforms.set_camera_position(
-            .set_camera_position(get_animated_camera_position(self.animation_start.elapsed()));
+            get_animated_camera_position(
+                self.animation_start.elapsed(),
+                self.get_max_dem_dimension(),
+            ),
+            self.get_dem_centre(),
+        );
         self.uniforms.update_buffer(queue);
         {
             let mut rpass = encoder.begin_render_pass(&wgpu::RenderPassDescriptor {
@@ -216,46 +227,61 @@ impl DemRenderer {
         }
         queue.submit(Some(encoder.finish()));
     }
+
+    fn get_max_dem_dimension(&self) -> f32 {
+        let dem = &self.source;
+        (dem.max_x - dem.min_x)
+            .max(dem.max_y - dem.max_y)
+            .max(dem.max_z - dem.min_x)
     }
 
-fn vertex(pos: [i8; 3]) -> Vertex {
+    fn get_dem_centre(&self) -> glam::Vec3 {
-    Vertex {
+        let dem = &self.source;
-        position: [pos[0] as f32, pos[1] as f32, pos[2] as f32, 1.0],
+        let min_corner = glam::Vec3::new(dem.min_x, dem.min_y, dem.min_z);
+        let max_corner = glam::Vec3::new(dem.max_x, dem.max_y, dem.max_z);
+        min_corner + (max_corner - min_corner) / 2.0
     }
 }
 
-fn create_vertices() -> (Vec<Vertex>, Vec<u16>) {
+fn create_vertices(dem: &Rc<Dem>) -> (Vec<Vertex>, Vec<u16>) {
+    let min_x = dem.min_x;
+    let max_x = dem.max_x;
+    let min_y = dem.min_y;
+    let max_y = dem.max_y;
+    let min_z = dem.min_z;
+    let max_z = dem.max_z;
+    
     let vertex_data = [
         // top (0, 0, 1)
-        vertex([-1, -1, 1]),
+        Vertex::new(min_x, min_y, max_z),
-        vertex([1, -1, 1]),
+        Vertex::new(max_x, min_y, max_z),
-        vertex([1, 1, 1]),
+        Vertex::new(max_x, max_y, max_z),
-        vertex([-1, 1, 1]),
+        Vertex::new(min_x, max_y, max_z),
         // bottom (0, 0, -1)
-        vertex([-1, 1, -1]),
+        Vertex::new(min_x, max_y, min_z),
-        vertex([1, 1, -1]),
+        Vertex::new(max_x, max_y, min_z),
-        vertex([1, -1, -1]),
+        Vertex::new(max_x, min_y, min_z),
-        vertex([-1, -1, -1]),
+        Vertex::new(min_x, min_y, min_z),
         // right (1, 0, 0)
-        vertex([1, -1, -1]),
+        Vertex::new(max_x, min_y, min_z),
-        vertex([1, 1, -1]),
+        Vertex::new(max_x, max_y, min_z),
-        vertex([1, 1, 1]),
+        Vertex::new(max_x, max_y, max_z),
-        vertex([1, -1, 1]),
+        Vertex::new(max_x, min_y, max_z),
         // left (-1, 0, 0)
-        vertex([-1, -1, 1]),
+        Vertex::new(min_x, min_y, max_z),
-        vertex([-1, 1, 1]),
+        Vertex::new(min_x, max_y, max_z),
-        vertex([-1, 1, -1]),
+        Vertex::new(min_x, max_y, min_z),
-        vertex([-1, -1, -1]),
+        Vertex::new(min_x, min_y, min_z),
         // front (0, 1, 0)
-        vertex([1, 1, -1]),
+        Vertex::new(max_x, max_y, min_z),
-        vertex([-1, 1, -1]),
+        Vertex::new(min_x, max_y, min_z),
-        vertex([-1, 1, 1]),
+        Vertex::new(min_x, max_y, max_z),
-        vertex([1, 1, 1]),
+        Vertex::new(max_x, max_y, max_z),
         // back (0, -1, 0)
-        vertex([1, -1, 1]),
+        Vertex::new(max_x, min_y, max_z),
-        vertex([-1, -1, 1]),
+        Vertex::new(min_x, min_y, max_z),
-        vertex([-1, -1, -1]),
+        Vertex::new(min_x, min_y, min_z),
-        vertex([1, -1, -1]),
+        Vertex::new(max_x, min_y, min_z),
     ];
 
     let index_data: &[u16] = &[
@@ -270,11 +296,11 @@ fn create_vertices() -> (Vec<Vertex>, Vec<u16>) {
     (vertex_data.to_vec(), index_data.to_vec())
 }
 
-fn get_animated_camera_position(animation_time: std::time::Duration) -> glam::Vec3 {
+fn get_animated_camera_position(animation_time: std::time::Duration, dem_size: f32) -> glam::Vec3 {
     let animation_phase = 2.0 * std::f32::consts::PI * (animation_time.as_secs_f32() % 10.0) / 10.0;
     glam::Vec3::new(
-        5.0 * f32::sin(animation_phase),
+        dem_size * f32::sin(animation_phase),
-        5.0 * f32::cos(animation_phase),
+        dem_size * f32::cos(animation_phase),
-        3.0,
+        dem_size * 0.7,
     )
 }