ade the test app print a prettier output

examples/test.rs

@@ -1,29 +1,60 @@
 extern crate vr;
 
-fn main() {
+fn print_matrix_4x4(offset: u32, mat: [[f32; 4]; 4]) {
-    let ivr = vr::IVRSystem::init().unwrap();
+    let off: String = (0..offset).map(|_| ' ').collect();
-    println!("bounds: {:?}", ivr.bounds());
+    println!("{:?}",        mat[0]);
-    println!("recommended size: {:?}", ivr.recommended_render_target_size());
+    println!("{}{:?}", off, mat[1]);
-    println!("eye output: {:?} {:?}", ivr.eye_viewport(vr::Eye::Left), ivr.eye_viewport(vr::Eye::Right));
+    println!("{}{:?}", off, mat[2]);
-    println!("projection matrix left {:?}", ivr.projection_matrix(vr::Eye::Left, 0.1, 100.));
+    println!("{}{:?}", off, mat[3]);
-    println!("projection matrix right {:?}", ivr.projection_matrix(vr::Eye::Right, 0.1, 100.));
+}
 
-    for u in 0..4 {
+fn print_matrix_4x3(offset: u32, mat: [[f32; 4]; 3]) {
-        for v in 0..4 {
+    let off: String = (0..offset).map(|_| ' ').collect();
+    println!("{:?}",        mat[0]);
+    println!("{}{:?}", off, mat[1]);
+    println!("{}{:?}", off, mat[2]);
+}
+
+fn main() {
+    let ivr = match vr::IVRSystem::init() {
+        Ok(ivr) => ivr,
+        Err(err) => {
+            println!("Failed to create IVR subsystem {:?}", err);
+            return;
+        }
+    };
+
+    println!("IVR was created");
+    println!("\tbounds: {:?}", ivr.bounds());
+    println!("\trecommended size: {:?}", ivr.recommended_render_target_size());
+    println!("\teye output: {:?} {:?}", ivr.eye_viewport(vr::Eye::Left), ivr.eye_viewport(vr::Eye::Right));
+    println!("\tvsync: {:?}", ivr.time_since_last_vsync());
+
+    print!("\tprojection matrix left  ");
+    print_matrix_4x4(31, ivr.projection_matrix(vr::Eye::Left, 0.1, 100.));
+    print!("\tprojection matrix right ");
+    print_matrix_4x4(31, ivr.projection_matrix(vr::Eye::Right, 0.1, 100.));
+
+    print!("\teye_to_head ");
+    print_matrix_4x3(8+12, ivr.eye_to_head_transform(vr::Eye::Left));
+
+    print!("\tposes ");
+    print_matrix_4x3(8+6, ivr.tracked_devices(0.).as_slice()[0].to_device);
+
+
+    println!("Distortion example");
+    for u in 0..2 {
+        for v in 0..2 {
             let pos = ivr.compute_distortion(
                 vr::Eye::Left,
                 u as f32 / 4.,
                 v as f32 / 4.,
             );
-            print!("({:2.4}, {:2.4}) ", pos.red[0], pos.red[1]);
+            print!("\t({:2.4}, {:2.4}) ", pos.red[0], pos.red[1]);
         }
         println!("");
     }
 
-    println!("eye_to_head: {:?}", ivr.eye_to_head_transform(vr::Eye::Left));
-    println!("vsync: {:?}", ivr.time_since_last_vsync());
-    println!("poses {:?}", ivr.tracked_devices(0.).as_slice());
-
     println!("Trying to create a compositor");
     match ivr.compositor() {
         Err(err) => println!("Could not create compositor {:?}", err),