Add chaperone examples to example

Generalize printing logic

examples/test.rs

@@ -1,18 +1,19 @@
 extern crate openvr;
 
-fn print_matrix_4x4(offset: u32, mat: [[f32; 4]; 4]) {
-    let off: String = (0..offset).map(|_| ' ').collect();
-    println!("{:?}",        mat[0]);
-    println!("{}{:?}", off, mat[1]);
-    println!("{}{:?}", off, mat[2]);
-    println!("{}{:?}", off, mat[3]);
-}
-
-fn print_matrix_4x3(offset: u32, mat: [[f32; 4]; 3]) {
-    let off: String = (0..offset).map(|_| ' ').collect();
-    println!("{:?}",        mat[0]);
-    println!("{}{:?}", off, mat[1]);
-    println!("{}{:?}", off, mat[2]);
+fn print_matrix<M, N>(offset: u32, mat: M)
+    where M: AsRef<[N]>,
+          N: AsRef<[f32]>,
+{
+    let offset: String = (0..offset).map(|_| ' ').collect();
+    let mut is_first_row = true;
+    for row in mat.as_ref() {
+        if !is_first_row {
+            print!("{}", offset);
+        }
+        let row_interior: Vec<_> = row.as_ref().iter().map(|x| format!("{:7.4}", x)).collect();
+        println!("[{}]", row_interior.join(", "));
+        is_first_row = false;
+    }
 }
 
 fn main() {
@@ -38,17 +39,17 @@ fn main() {
     println!("\tVSync: {:?}", system.time_since_last_vsync());
 
     print!("\tProjection matrix left  ");
-    print_matrix_4x4(31, system.projection_matrix(openvr::Eye::Left, 0.1, 100.));
+    print_matrix(32, system.projection_matrix(openvr::Eye::Left, 0.1, 100.));
     print!("\tProjection matrix right ");
-    print_matrix_4x4(31, system.projection_matrix(openvr::Eye::Right, 0.1, 100.));
+    print_matrix(32, system.projection_matrix(openvr::Eye::Right, 0.1, 100.));
 
     print!("\tEye to head left ");
-    print_matrix_4x3(8+12, system.eye_to_head_transform(openvr::Eye::Left));
+    print_matrix(25, system.eye_to_head_transform(openvr::Eye::Left));
 
     print!("\tPoses ");
     let poses = system.device_to_absolute_tracking_pose(openvr::TrackingUniverseOrigin::RawAndUncalibrated, 0.0);
     for pose in poses.iter() {
-        print_matrix_4x3(8+6, *pose.device_to_absolute_tracking());
+        print_matrix(8+6, pose.device_to_absolute_tracking());
         break;
     }
 
@@ -60,9 +61,9 @@ fn main() {
                 u as f32 / 4.,
                 v as f32 / 4.,
             ).unwrap();
-            print!("\t\t({:2.4}, {:2.4}) ", pos.red[0], pos.red[1]);
+            print!("\t\t({:7.4}, {:7.4}) ", pos.red[0], pos.red[1]);
         }
-        println!("");
+        println!();
     }
 
     let comp = match context.compositor() {
@@ -72,13 +73,34 @@ fn main() {
             return;
         }
     };
+    println!();
 
-    println!("\nIVRCompositor was created");
+    println!("IVRCompositor was created");
     println!("\tIs fullscreen = {}", comp.is_fullscreen());
     println!("\tVulkan Instance Extensions:");
     for ext in comp.vulkan_instance_extensions_required() {
         println!("\t\t{:?}", ext);
     }
+    println!();
+
+    println!("IVRChaperone was created");
+    let chaperone = match context.chaperone() {
+        Ok(sys) => sys,
+        Err(err) => {
+            println!("Failed to get chaperone interface: {}", err);
+            return;
+        }
+    };
+    println!("\tCalibration state: {:?}", chaperone.get_calibration_state());
+    println!("\tPlay area size: {:?}", chaperone.get_play_area_size());
+    print!("\tPlay area rect: ");
+    if let Some(play_area_rect) = chaperone.get_play_area_rect() {
+        print_matrix(24, &play_area_rect);
+    } else {
+        println!("None");
+    }
+    println!("\tAre bounds visible = {:?}", chaperone.are_bounds_visible());
+    println!();
 
     println!("Done! \\o/");
 }