From 22d37b09726f4d6113816145f2101c4c3298e4c0 Mon Sep 17 00:00:00 2001
From: Eugen Wissner <belka@caraus.de>
Date: Mon, 29 Jan 2024 20:13:43 +0100
Subject: [PATCH] Dump glyph coordinates

---
 src/Graphics/Fountainhead/Dumper.hs | 36 +++++++++++++++++++++++++----
 1 file changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/Graphics/Fountainhead/Dumper.hs b/src/Graphics/Fountainhead/Dumper.hs
index 8925694..84d8661 100644
--- a/src/Graphics/Fountainhead/Dumper.hs
+++ b/src/Graphics/Fountainhead/Dumper.hs
@@ -662,15 +662,41 @@ dumpGlyf (GlyfTable glyfDescriptions) = dumpCaption "'glyf' Table - Glyf data"
         <> foldMap dumpEndPoint (Vector.indexed endPtsOfContours) <> newlineBuilder
         <> "         Length of Instructions: "
         <> Text.Builder.decimal (Vector.length instructions) <> newlineBuilder
-        <> "         Flags" <> newlineBuilder
+        <> newlineBuilder <> "         Flags" <> newlineBuilder
         <> "         -----" <> newlineBuilder
-        <> foldMap dumpFlag (Vector.indexed coordinates) <>  newlineBuilder <> newlineBuilder
-    dumpGlyphDefinition _ = ""
-    dumpFlag (coordinateIndex, GlyphCoordinate{..})
+        <> foldMap dumpFlag (Vector.indexed coordinates) <>  newlineBuilder
+        <> "         Coordinates" <> newlineBuilder
+        <> "         -----------" <> newlineBuilder
+        <> dumpCoordinates coordinates
+    dumpGlyphDefinition _ = "" -- TODO
+    dumpFlag (coordinateIndex, GlyphCoordinate{..}) -- TODO
         = "         " <> justifyNumber 2 coordinateIndex <> ": "
-        <> Text.Builder.decimal coordinateX <> " " <> Text.Builder.decimal coordinateY <> " "
         <> (if onCurve then "On" else "Off")
         <> newlineBuilder
+    dumpCoordinates coordinates =
+        let initial = ("", GlyphCoordinate 0 0 True)
+         in fst $ Vector.ifoldl' foldCoordinate initial coordinates
+    foldCoordinate
+        :: (Text.Builder.Builder, GlyphCoordinate)
+        -> Int
+        -> GlyphCoordinate
+        -> (Text.Builder.Builder, GlyphCoordinate)
+    foldCoordinate (accumulator, absCoordinate) coordinateIndex relCoordinate =
+        let nextAbs = GlyphCoordinate
+                { coordinateX = sumCoordinate (getField @"coordinateX") relCoordinate absCoordinate
+                , coordinateY = sumCoordinate (getField @"coordinateY") relCoordinate absCoordinate
+                , onCurve = getField @"onCurve" relCoordinate -- Not used.
+                }
+            newLine = "         " <> justifyNumber 2 coordinateIndex
+                <> " Rel " <> dumpCoordinate relCoordinate
+                <> " -> Abs " <> dumpCoordinate nextAbs
+                <> newlineBuilder
+         in (accumulator <> newLine, nextAbs)
+    sumCoordinate getAxis relCoordinate absCoordinate =
+        getAxis relCoordinate + getAxis absCoordinate
+    dumpCoordinate GlyphCoordinate{..}
+        = "(" <> justifyNumber 7 coordinateX <> ", "
+        <> justifyNumber 7 coordinateY <> ")"
 
 dumpTables
     :: Megaparsec.State ByteString Void