document BBox object

pdf-raku · Dec 15, 2023 · 2782838 · 2782838
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diff --git a/Makefile.in b/Makefile.in
@@ -44,7 +44,7 @@ $(DocLinker) :
 Pod-To-Markdown-installed :
 	@raku -M Pod::To::Markdown -c
 
-doc : $(DocLinker) Pod-To-Markdown-installed docs/index.md docs/Font/FreeType.md docs/Font/FreeType/BitMap.md docs/Font/FreeType/CharMap.md docs/Font/FreeType/Face.md docs/Font/FreeType/Glyph.md docs/Font/FreeType/GlyphImage.md docs/Font/FreeType/Outline.md docs/Font/FreeType/SizeMetrics.md docs/Font/FreeType/NamedInfo.md docs/Font/FreeType/Raw.md docs/Font/FreeType/Raw/Defs.md docs/Font/FreeType/Raw/TT_Sfnt.md
+doc : $(DocLinker) Pod-To-Markdown-installed docs/index.md docs/Font/FreeType.md docs/Font/FreeType/BBox.md docs/Font/FreeType/BitMap.md docs/Font/FreeType/CharMap.md docs/Font/FreeType/Face.md docs/Font/FreeType/Glyph.md docs/Font/FreeType/GlyphImage.md docs/Font/FreeType/Outline.md docs/Font/FreeType/SizeMetrics.md docs/Font/FreeType/NamedInfo.md docs/Font/FreeType/Raw.md docs/Font/FreeType/Raw/Defs.md docs/Font/FreeType/Raw/TT_Sfnt.md
 
 test : all
 	@prove -e"raku -I ." -j $(TEST_JOBS) t

diff --git a/docs/Font/FreeType/BBox.md b/docs/Font/FreeType/BBox.md
@@ -0,0 +1,54 @@
+[[Raku PDF Project]](https://pdf-raku.github.io)
+ / [[Font-FreeType Module]](https://pdf-raku.github.io/Font-FreeType-raku)
+ / [Font::FreeType](https://pdf-raku.github.io/Font-FreeType-raku/Font/FreeType)
+ :: [BBox](https://pdf-raku.github.io/Font-FreeType-raku/Font/FreeType/BBox)
+
+class Font::FreeType::BBox
+--------------------------
+
+A generic font or glyph bounding box
+
+Synopsis
+--------
+
+```raku
+use Font::FreeType;
+use Font::FreeType::BBox;
+use Font::FreeType::Face;
+use Font::FreeType::Glyph;
+
+my Font::FreeType $freetype .= new;
+my Font::FreeType::Face $vera = $freetype.face('t/fonts/Vera.ttf');
+constant FontSize = 12;
+# get the font bounding box
+$vera.set-font-size(FontSize);
+
+my Font::FreeType::BBox $bbox = $vera.bbox;
+say 'font "%s" (%s) %dpt has bbox [%.1f, %.1f, %.1f, %.1f]'.sprintf($vera.family-name, $vera.style-name, FontSize, $bbox.x-min, $bbox.y-min, $bbox.x-max, $bbox.y-max);
+# get the bounding box for an individual glyph
+$vera.for-glyphs: "X", -> Font::FreeType::Glyph $glyph {
+    my Font::FreeType::BBox $bbox = $glyph.bounding-box;
+    say 'glyph "%s" %dpt has bbox [%.1f, %.1f, %.1f, %.1f]'.sprintf($glyph.Str, FontSize, |$bbox);
+}
+```
+
+Description
+-----------
+
+This object is a subclass of Array. It represents a bounding box as 4 elements with accessor aliases `x-min`, `y-min`, `x-max` and `y-max`.
+
+Methods
+-------
+
+`x-min`, `y-min`, `x-max`, `y-max`
+
+The bottom-left and top right coordinates of the bounding box. These can also be accessed as a four element array.
+
+`width`, `height`
+
+Aliases for `x-max - x-min` and `y-max - y-min`.
+
+`x-scale`, `y-scale`
+
+The bounding `x` and `y` scale of the bounding box.
+
diff --git a/docs/Font/FreeType/Face.md b/docs/Font/FreeType/Face.md
@@ -27,7 +27,7 @@ use Font::FreeType;
 use Font::FreeType::Face;
 
 my Font::FreeType $freetype .= new;
-my Font::Freetype::face $vera = $freetype.face('Vera.ttf');
+my Font::Freetype::Face $vera = $freetype.face('Vera.ttf');
 ```
 
 Description
@@ -304,9 +304,9 @@ The current active [Font::FreeType::CharMap](https://pdf-raku.github.io/Font-Fre
 
 An array of the available [Font::FreeType::CharMap](https://pdf-raku.github.io/Font-FreeType-raku/Font/FreeType/CharMap) objects for the face.
 
-### bounding-box()
+### bounding-box() [or bbox()]
 
-The outline's bounding box returned as a 4 element array: `($x-min, $y-min, $x-max, $y-max)`.
+The outline's bounding box returned as a [Font::FreeType::BBox](https://pdf-raku.github.io/Font-FreeType-raku/Font/FreeType/BBox) array: `($x-min, $y-min, $x-max, $y-max)`.
 
 ### raw()
 

diff --git a/lib/Font/FreeType/BBox.rakumod b/lib/Font/FreeType/BBox.rakumod
@@ -43,27 +43,43 @@ class Font::FreeType::BBox
 
     =begin code :lang<raku>
     use Font::FreeType;
-    use Font::FreeType::Face;
     use Font::FreeType::BBox;
+    use Font::FreeType::Face;
+    use Font::FreeType::Glyph;
 
     my Font::FreeType $freetype .= new;
-    my Font::Freetype::Face $vera = $freetype.face('Vera.ttf');
-
+    my Font::FreeType::Face $vera = $freetype.face('t/fonts/Vera.ttf');
+    constant FontSize = 12;
     # get the font bounding box
-    my Font::FreeType::BBox $bbox = $vera.bbox;
-    say $bbox.x-min;
-    say $bbox.x-max;
-    say $bbox.width;
-    say $bbox.height;
+    $vera.set-font-size(FontSize);
 
+    my Font::FreeType::BBox $bbox = $vera.bbox;
+    say 'font "%s" (%s) %dpt has bbox [%.1f, %.1f, %.1f, %.1f]'.sprintf($vera.family-name, $vera.style-name, FontSize, $bbox.x-min, $bbox.y-min, $bbox.x-max, $bbox.y-max);
     # get the bounding box for an individual glyph
-    $vera.for-glyphs: "X", -> $gslot {
+    $vera.for-glyphs: "X", -> Font::FreeType::Glyph $glyph {
+        my Font::FreeType::BBox $bbox = $glyph.bounding-box;
+        say 'glyph "%s" %dpt has bbox [%.1f, %.1f, %.1f, %.1f]'.sprintf($glyph.Str, FontSize, |$bbox);
     }
     =end code
 
 =head2 Description
-           
+
+This object is a subclass of Array. It represents a bounding box as 4 elements
+with accessor aliases `x-min`, `y-min`, `x-max` and `y-max`.
 
 =head2 Methods
 
+`x-min`, `y-min`, `x-max`, `y-max`
+
+The bottom-left and top right coordinates of the bounding box. These
+can also be accessed as a four element array.
+
+`width`, `height`
+
+Aliases for `x-max - x-min` and `y-max - y-min`.
+
+`x-scale`, `y-scale`
+
+The bounding `x` and `y` scale of the bounding box.
+
 =end pod
diff --git a/lib/Font/FreeType/Glyph.rakumod b/lib/Font/FreeType/Glyph.rakumod
@@ -40,7 +40,7 @@ class Font::FreeType::Glyph {
     method height returns Rat:D { $.metrics.height / $!y-scale }
     method format returns UInt:D { FT_GLYPH_FORMAT($!raw.format) }
 
-    method glyph-image handles<bitmap outline decompose> returns Font::FreeType::GlyphImage:D {
+    method glyph-image handles<bitmap decompose> returns Font::FreeType::GlyphImage:D {
         my $top = $!raw.bitmap-top;
         my $left = $!raw.bitmap-left;
         Font::FreeType::GlyphImage.new: :$.face, :glyph($!raw), :$left, :$top, :$.char-code, :$.index, :$.stat;

diff --git a/lib/Font/FreeType/_Glyph.rakumod b/lib/Font/FreeType/_Glyph.rakumod
@@ -22,7 +22,7 @@ method is-outline {
     .format == FT_GLYPH_FORMAT_OUTLINE with $.raw;
 }
 
-method outline handles<decompose> returns  Font::FreeType::Outline:D {
+method outline handles<decompose bbox bounding-box> returns  Font::FreeType::Outline:D {
     die "not an outline glyph"
         unless self.is-outline;
     my FT_Outline:D $outline = $.raw.outline;

diff --git a/t/10metrics_verasans.t b/t/10metrics_verasans.t
@@ -7,9 +7,10 @@
 
 use v6;
 use Test;
-plan 2714;
+plan 2715;
 use Font::FreeType;
 use Font::FreeType::SizeMetrics;
+use Font::FreeType::Glyph;
 use Font::FreeType::Raw::Defs;
 
 # Load the Vera Sans face.
@@ -167,7 +168,7 @@ is $i, +@character-list, "we aren't missing any glyphs";
 
 $i = 0;
 $vera.forall-char-images: &check-glyph-char;
-is $i, +@character-list, "we aren't missing any glyphs";
+is $i, +@character-list, "we aren't missing any glyph images";
 
 # Test metrics on some particlar glyphs.
 my %glyph-metrics = (
@@ -185,9 +186,9 @@ my %glyph-metrics = (
 
 # 5*2 tests.
 my $chars = %glyph-metrics.keys.sort.join;
-$vera.for-glyphs: $chars, -> $glyph {
+$vera.for-glyphs: $chars, -> Font::FreeType::Glyph $glyph {
     my $char = $glyph.Str;
-    with %glyph-metrics{$char} {
+    given %glyph-metrics{$char} {
         is $glyph.name, .<name>,
            "name of glyph '$char'";
         is $glyph.horizontal-advance, .<advance>,
@@ -200,8 +201,10 @@ $vera.for-glyphs: $chars, -> $glyph {
            "width of glyph '$char'";
         is $glyph.height, $_, "height of '$char'"
             with .<Height>;
-        is-deeply $glyph.outline.bounding-box.Array, $_, "bbox of '$char'"
-            with .<BBox>;
+        with .<BBox> {
+            is-deeply $glyph.outline.bounding-box.Array, $_, "bbox of '$char'";
+            is-deeply $glyph.glyph-image.outline.bounding-box.Array, $_, "outline.bbox of '$char'";
+        }
 
     }
 }