minor documentation clarification

[imager.git] / Imager.pm

diff --git a/Imager.pm b/Imager.pm
index 3ba16cf6cd812e73f985bc31150c48daa92d3376..19dab111a0547c173689562769c1200190cf86f0 100644 (file)
--- a/Imager.pm
+++ b/Imager.pm
@@ -562,6 +562,9 @@ sub img_set {
     $self->{IMG} = i_img_pal_new($hsh{xsize}, $hsh{ysize}, $hsh{channels},
                                  $hsh{maxcolors} || 256);
   }
+  elsif ($hsh{bits} eq 'double') {
+    $self->{IMG} = i_img_double_new($hsh{xsize}, $hsh{ysize}, $hsh{channels});
+  }
   elsif ($hsh{bits} == 16) {
     $self->{IMG} = i_img_16_new($hsh{xsize}, $hsh{ysize}, $hsh{channels});
   }
@@ -683,7 +686,11 @@ sub findcolor {
 
 sub bits {
   my $self = shift;
-  $self->{IMG} and i_img_bits($self->{IMG});
+  my $bits = $self->{IMG} && i_img_bits($self->{IMG});
+  if ($bits && $bits == length(pack("d", 1)) * 8) {
+    $bits = 'double';
+  }
+  $bits;
 }
 
 sub type {
@@ -2237,15 +2244,22 @@ Warning: if you draw on a paletted image with colors that aren't in
 the palette, the image will be internally converted to a normal image.
 
 For improved color precision you can use the bits parameter to specify
-16 bites per channel:
+16 bit per channel:
 
   $img = Imager->new(xsize=>200, ysize=>200, channels=>3, bits=>16);
 
-Note that as of this writing all functions should work on 16-bit
-images, but at only 8-bit/channel precision.
+or for even more precision:
+
+  $img = Imager->new(xsize=>200, ysize=>200, channels=>3, bits=>'double');
 
-Currently only 8 and 16/bit per channel image types are available,
-this may change later.
+to get an image that uses a double for each channel.
+
+Note that as of this writing all functions should work on images with
+more than 8-bits/channel, but many will only work at only
+8-bit/channel precision.
+
+Currently only 8-bit, 16-bit, and double per channel image types are
+available, this may change later.
 
 Color objects are created by calling the Imager::Color->new()
 method:
@@ -2797,7 +2811,8 @@ the function return undef.  Examples:
   }
 
 The bits() method retrieves the number of bits used to represent each
-channel in a pixel, typically 8.  The type() method returns either
+channel in a pixel, 8 for a normal image, 16 for 16-bit image and
+'double' for a double/channel image.  The type() method returns either
 'direct' for truecolor images or 'paletted' for paletted images.  The
 virtual() method returns non-zero if the image contains no actual
 pixels, for example masked images.
@@ -2993,7 +3008,8 @@ parameter which can take the values C<h>, C<v>, C<vh> and C<hv>.
 
 =head2 Rotating images
 
-Use the rotate() method to rotate an image.
+Use the rotate() method to rotate an image.  This method will return a
+new, rotated image.
 
 To rotate by an exact amount in degrees or radians, use the 'degrees'
 or 'radians' parameter:
@@ -3001,6 +3017,9 @@ or 'radians' parameter:
   my $rot20 = $img->rotate(degrees=>20);
   my $rotpi4 = $img->rotate(radians=>3.14159265/4);
 
+Exact image rotation uses the same underlying transformation engine as
+the matrix_transform() method.
+
 To rotate in steps of 90 degrees, use the 'right' parameter:
 
   my $rotated = $img->rotate(right=>270);