From eae81e5b33bcab0437934e558158237cfef78d8f Mon Sep 17 00:00:00 2001
From: Bernie Innocenti <bernie@codewiz.org>
Date: Thu, 4 May 2017 23:27:42 -0400
Subject: [PATCH] Convert bounding_box to a struct.

---
 bounding_box.rs | 86 ++++++++++++++++++++++++++-----------------------
 main.rs         |  5 +--
 2 files changed, 48 insertions(+), 43 deletions(-)

diff --git a/bounding_box.rs b/bounding_box.rs
index 95d3608..ce06b52 100644
--- a/bounding_box.rs
+++ b/bounding_box.rs
@@ -9,47 +9,51 @@ pub fn solid_fill_program(display: &Display) -> Program {
     return Program::from_source(display, vertex_shader_src, fragment_shader_src, None).unwrap();
 }
 
-pub fn draw<U>(display: &Display,
-               frame: &mut glium::Frame,
-               program: &Program,
-               uniforms: &U,
-               cube: &Cube) where U: glium::uniforms::Uniforms {
-
-    #[derive(Copy, Clone)]
-    struct Vertex { position: [f32; 3] }
-    implement_vertex!(Vertex, position);
-
-    let cube = [
-        Vertex { position: [cube.xmin, cube.ymin, cube.zmin] },
-        Vertex { position: [cube.xmax, cube.ymin, cube.zmin] },
-        Vertex { position: [cube.xmax, cube.ymax, cube.zmin] },
-        Vertex { position: [cube.xmin, cube.ymax, cube.zmin] },
-        Vertex { position: [cube.xmin, cube.ymin, cube.zmax] },
-        Vertex { position: [cube.xmax, cube.ymin, cube.zmax] },
-        Vertex { position: [cube.xmax, cube.ymax, cube.zmax] },
-        Vertex { position: [cube.xmin, cube.ymax, cube.zmax] },
-    ];
-    let vb = glium::VertexBuffer::new(display, &cube).unwrap();
+#[derive(Copy, Clone)]
+struct Vertex { position: [f32; 3] }
+implement_vertex!(Vertex, position);
+
+pub struct BoundingBox<'a> {
+    vertexes: glium::VertexBuffer<Vertex>,
+    program: &'a Program,
+    indices: IndexBuffer<u16>,
+}
 
-    let params = glium::DrawParameters {
-        depth: glium::Depth {
-            test: glium::draw_parameters::DepthTest::IfLess,
-            write: true,
+impl<'a> BoundingBox<'a> {
+    pub fn new(display: &Display, c: &Cube, program: &'a Program) -> BoundingBox<'a> {
+        let vertex_data = [
+            Vertex { position: [c.xmin, c.ymin, c.zmin] },
+            Vertex { position: [c.xmax, c.ymin, c.zmin] },
+            Vertex { position: [c.xmax, c.ymax, c.zmin] },
+            Vertex { position: [c.xmin, c.ymax, c.zmin] },
+            Vertex { position: [c.xmin, c.ymin, c.zmax] },
+            Vertex { position: [c.xmax, c.ymin, c.zmax] },
+            Vertex { position: [c.xmax, c.ymax, c.zmax] },
+            Vertex { position: [c.xmin, c.ymax, c.zmax] },
+        ];
+
+        const INDICES: &[u16] = &[0, 1, 1, 2, 2, 3, 3, 0,   // front
+                                  4, 5, 5, 6, 6, 7, 7, 4,   // back
+                                  0, 4, 1, 5, 2, 6, 3, 7];  // sides
+
+        BoundingBox {
+            vertexes: glium::VertexBuffer::new(display, &vertex_data).unwrap(),
+            program: program,
+            indices:  IndexBuffer::new(display, PrimitiveType::LinesList, INDICES).unwrap(),
+        }
+    }
+
+    pub fn draw<U>(&self, frame: &mut glium::Frame,
+                   uniforms: &U) where U: glium::uniforms::Uniforms {
+        let params = glium::DrawParameters {
+            depth: glium::Depth {
+                test: glium::draw_parameters::DepthTest::IfLess,
+                write: true,
+                ..Default::default()
+            },
+            blend: glium::Blend::alpha_blending(),
             ..Default::default()
-        },
-        blend: glium::Blend::alpha_blending(),
-        ..Default::default()
-    };
-
-    let front_indices = IndexBuffer::new(display, PrimitiveType::LineLoop,
-                                         &[0, 1, 2, 3u16]).unwrap();
-    frame.draw(&vb, &front_indices, program, uniforms, &params).unwrap();
-
-    let back_indices = IndexBuffer::new(display, PrimitiveType::LineLoop,
-                                        &[4, 5, 6, 7u16]).unwrap();
-    frame.draw(&vb, &back_indices, program, uniforms, &params).unwrap();
-
-    let sides_indices = IndexBuffer::new(display, PrimitiveType::LinesList,
-                                         &[0, 4, 1, 5, 2, 6, 3, 7u16]).unwrap();
-    frame.draw(&vb, &sides_indices, program, uniforms, &params).unwrap();
+        };
+        frame.draw(&self.vertexes, &self.indices, &self.program, uniforms, &params).unwrap();
+    }
 }
diff --git a/main.rs b/main.rs
index 9c223c9..8315a3b 100644
--- a/main.rs
+++ b/main.rs
@@ -105,6 +105,7 @@ fn main() {
         zmin: -1.1,
         zmax:  1.1,
     };
+    let mandelwow_bbox = bounding_box::BoundingBox::new(&display, &bounds, &bounding_box_program);
 
     set_main_loop_callback(|| {
         camera.update();
@@ -126,7 +127,7 @@ fn main() {
         frame.clear_color_and_depth((0.0, 0.0, 0.0, 1.0), 1.0);
 
         let rotation = cgmath::Matrix4::from(
-            Euler { x: Rad(t.sin() / 3.), y: Rad(t.sin() / 2.), z: Rad(t)});
+            Euler { x: Rad(t.sin() / 3.), y: Rad(t.sin() / 2.), z: Rad(t / 1.5)});
         let z_trans = -2.0;  // Send the model back a little bit so it fits the screen.
         let model2 =
             Matrix4::from_translation(Vector3::unit_z() * z_trans) * rotation;
@@ -140,7 +141,7 @@ fn main() {
                 view:  camera.get_view(),
                 perspective: camera.get_perspective(),
             };
-            bounding_box::draw(&display, &mut frame, &bounding_box_program, &uniforms, &bounds);
+            mandelwow_bbox.draw(&mut frame, &uniforms);
         }
 
         mandelwow::draw(&display, &mut frame, &mandelwow_program, model, &camera, &bounds, wow);
-- 
2.25.1