add tests for Quaternion, normalize_this -> fluent normalise

Author: mohawk2

MANIFEST

@@ -45,3 +45,4 @@ MANIFEST			This list of files
 MANIFEST.SKIP
 t/arcball.t
 t/opengl.t
+t/quaternion.t

lib/PDL/Graphics/TriD/ArcBall.pm

@@ -86,8 +86,7 @@ sub normxy2qua {
 	if ($dist > 1.0) {$x /= $dist; $y /= $dist; $dist = 1.0;}
 	my $z = 1-$dist;
 	my $qua = PDL::Graphics::TriD::Quaternion->new(0,$x,$y,$z);
-	$qua->normalize_this();
-	return $qua;
+	$qua->normalise;
 }
 
 # Tjl's version2: a bowl -- angle is proportional to displacement.
@@ -103,8 +102,7 @@ sub normxy2qua {
 	if ($dist > 1.0) {$x /= $dist; $y /= $dist; $dist = 1.0;}
 	my $z = cos($dist*3.142/2);
 	my $qua = PDL::Graphics::TriD::Quaternion->new(0,$x,$y,$z);
-	$qua->normalize_this();
-	return $qua;
+	$qua->normalise;
 }
 
 1;

lib/PDL/Graphics/TriD/Control3D.pm

@@ -25,8 +25,8 @@ sub new{
 }
 
 sub normalize { my($this) = @_;
-	$this->{WRotation}->normalize_this();
-	$this->{CRotation}->normalize_this();
+	$this->{WRotation}->normalise;
+	$this->{CRotation}->normalise;
 }
 
 sub reset { 

lib/PDL/Graphics/TriD/GL.pm

@@ -175,7 +175,7 @@ sub PDL::Graphics::TriD::Quaternion::togl {
   my($this) = @_;
   if(abs($this->[0]) == 1) { return ; }
   if(abs($this->[0]) >= 1) {
-    $this->normalize_this();
+    $this->normalise;
   } 
   glRotatef(2*POSIX::acos($this->[0])/3.14*180, @{$this}[1..3]);
 }

lib/PDL/Graphics/TriD/Quaternion.pm

@@ -6,7 +6,7 @@
 #
 # Stored as [c,x,y,z].
 #
-# XXX REMEMBER!!!! First component = cos(angle*2), *NOT* cos(angle)
+# XXX REMEMBER!!!! First component = cos(angle/2), *NOT* cos(angle)
 
 package PDL::Graphics::TriD::Quaternion;
 
@@ -29,15 +29,14 @@ sub new {
 }
 
 sub copy {
-	return PDL::Graphics::TriD::Quaternion->new(@{$_[0]});
+  PDL::Graphics::TriD::Quaternion->new(@{$_[0]});
 }
 
 sub new_vrmlrot {
 	my($type,$x,$y,$z,$c) = @_;
 	my $l = sqrt($x**2+$y**2+$z**2);
 	my $this = bless [cos($c/2),map {sin($c/2)*$_/$l} $x,$y,$z],$type;
-	$this->normalize_this();
-	return $this;
+	$this->normalise;
 }
 
 sub to_vrmlrot {
@@ -123,15 +122,16 @@ sub invert_rotation_this {
 	$this->[0] = - $this->[0];
 }
 
-sub normalize_this {
-	my($this) = @_;
-	my $abs = sqrt($this->abssq());
-	@$this = map {$_/$abs} @$this;
+sub normalise {
+  my($this) = @_;
+  my $abs = sqrt($this->abssq);
+  @$this = map $_/$abs, @$this;
+  $this;
 }
 
 sub rotate {
   my($this,$vec) = @_;
-  my $q = (PDL::Graphics::TriD::Quaternion)->new(0,@$vec);
+  my $q = PDL::Graphics::TriD::Quaternion->new(0,@$vec);
   my $m = $this->multiply($q->multiply($this->invert));
   return [@$m[1..3]];
 }

lib/PDL/Graphics/TriD/VRML.pm

@@ -153,8 +153,8 @@ sub PDL::Graphics::TriD::Transformation::tovrml {
 sub PDL::Graphics::TriD::Quaternion::tovrml {my($this) = @_;
 	if(abs($this->[0]) == 1) { return ; }
 	if(abs($this->[0]) >= 1) {
-		# die "Unnormalized Quaternion!\n";
-		$this->normalize_this();
+		# die "Unnormalised Quaternion!\n";
+		$this->normalise;
 	}
 	PDL::Graphics::VRMLNode->new('Transform',
 		   'rotation',vrml3v(@{$this}[1..3])." $this->[0]");

t/quaternion.t

@@ -0,0 +1,21 @@
+use strict;
+use warnings;
+use Test::More;
+
+use PDL::Graphics::TriD::Quaternion;
+use PDL::LiteF;
+use Test::PDL;
+
+sub is_qua {
+  local $Test::Builder::Level = $Test::Builder::Level + 1;
+  my ($got, $exp) = map PDL->pdl(@$_), @_;
+  is_pdl $got, $exp;
+}
+
+my $q = PDL::Graphics::TriD::Quaternion->new(0,0,0,1);
+isa_ok $q, 'PDL::Graphics::TriD::Quaternion';
+is_qua $q, [0,0,0,1];
+
+is_qua +PDL::Graphics::TriD::Quaternion->new(0,0,0,2)->normalise, [0,0,0,1];
+
+done_testing;