amend scaleConfigToDesiredWidth function

to scale to only 98% of the desired width.  This should prevent margin
errors when we eventually render the final score where there would be
the possibilty otherwise of slightly overextending the width because of
rounding issues etc.

Author: newlandsvalley

examples/scaling/src/Main.purs

@@ -9,9 +9,7 @@ import VexFlow.Types (Config, RenderingError, defaultConfig)
 import Data.Abc.Parser (parse)
 import Data.Abc (AbcTune)
 import Examples.Scaling.Texts (arepolskan, augustsson, cig, eklund3, ewa, fastan, smalandPolska,
-                                chordSymbolExample, gustavPersson, voltaContinuationSample,
-                                keyChangeSample, meterChangeSample,
-                                continuationSample, emptyBarSample)
+                                gustavPersson, bakmes)
 
 config :: Config
 config =
@@ -23,11 +21,11 @@ config =
 
 main :: Effect (Maybe RenderingError)
 main =
-  case (parse cig) of
+  case (parse bakmes) of
     Right abcTune -> do
       renderer <- initialiseCanvas config
       let
-        desiredWidth = 500
+        desiredWidth = 580
       renderFinalTuneAtWidth config desiredWidth renderer abcTune
     _ ->
       pure $ Just "ABC failed to parse"

examples/scaling/src/Texts.purs

@@ -121,48 +121,15 @@ arepolskan =
   <> "|: g | f2a g3 d2B | c2d ege dcB | A2G FG2 A2B | cdc BAG A2F |\r\n"
   <> "D2g fg2 d2B | c2d ege dcB | A2G FG2 ABc |1 cB2 G3-G2 :|2 cB2 G6 |\r\n"
 
--- example with chord symbols
-chordSymbolExample :: String
-chordSymbolExample =
-  "X:1\r\n"
-    <> "T:Polska från Fjällnäs\r\n"
-    <> "R:Polska\r\n"
-    <> "L:1/8\r\n"
-    <> "M:3/4\r\n"
-    <> "K:G\r\n"
-    <> " \"G\"G2G>B \"D7\"A>F | \"G\"G2B>dg2 | \"Am\"a2a>g \"D7\"fe/f/ |1 \"G\"g2b>g \"D7\"d>B :|2 \"G\"g2g4 |]\r\n"
-    <> "|: \"G\"d2B>d g>f | \"C\"e2e>dc2 | \"D7\"a2a>g fe/f/ |1 \"G\"g2b>g \"D7\"d>B :|2 \"G\"g2g4 |]\r\n"
-
-
-keyChangeSample :: String
-keyChangeSample =
-  "K: D\r\n"
-  <> "M: 4/4\r\n"
-  <> "| A B c |[K: A] F |\r\n"
-  <> "| f g a |\r\n"
-
-meterChangeSample :: String
-meterChangeSample =
-  "K: D\r\n"
-  <> "M: 4/4\r\n"
-  <> "| A B c |\r\n"
+bakmes :: String
+bakmes =
+  "X: 1\r\n"
+  <> "T: Bakmes av Åker Erland Jonsson\r\n"
+  <> "R: polska\r\n"
   <> "M: 3/4\r\n"
-  <> "| f g a |\r\n"
-
-continuationSample :: String
-continuationSample =
-  "| ABc |\\\r\n| def |\r\n"
-
-emptyBarSample :: String
-emptyBarSample =
-  "| ABc | | def |\r\n"
-
-voltaContinuationSample :: String
-voltaContinuationSample =
-    "X:1\r\n"
-    <> "T: volta continued across staves\r\n"
-    <> "M: 3/4\r\n"
-    <> "L: 1/8\r\n"
-    <> "K: D\r\n"
-    <> "| AB cd ef |1 bb cc dd :|2 dd cc bb | AA BB cc |\r\n"
-    <> "| dd ee ff || g6 |\r\n"
+  <> "L: 1/8\r\n"
+  <> "K:Gmin\r\n"
+  <> "|: D | G>G-GA Bc | d>d-dc Ac | B>B-BA G^F | G2 D3 D | \r\n"
+  <> "G>G-GA Bc | d>d-dc Ac | B>B-BA G^F | G2 G3 :|\r\n" 
+  <> "|: d>d-d=e fg | d>d-dc Ac | B>B-BA Bc | (3d2c2B2 AB/2A/2 |\r\n"
+  <> "G>G-GA Bc | d2 B4 | (3ABc A^FDF | G2 G4 :|\r\n"

src/VexFlow/Score.purs

@@ -27,7 +27,7 @@ import Data.Maybe (Maybe(..), fromMaybe, maybe)
 import Data.String (length) as String
 import Data.Traversable (traverse_)
 import Effect (Effect)
-import Prelude ((<>), (*), (==), (/), (/=), (<=), (&&), ($), (+), (>), Unit, bind, discard, not, pure, when)
+import Prelude ((<>), (*), (==), (/), (/=), (<=), (&&), ($), (+), (>), Unit, bind, discard, not, pure, show, when)
 import VexFlow.Abc.Alignment (centeredTitleXPos, justifiedScoreConfig, rightJustifiedOriginXPos)
 import VexFlow.Abc.Alignment (rightJustify) as Exports
 import VexFlow.Abc.TranslateStateful (runTuneBody)
@@ -89,7 +89,11 @@ renderFinalTune config renderer abcTune =
   in
     -- don't render if the tune width exceded the requested canvas width
     if (config'.width > config.width) then 
-      pure $ Just "Canvas width exceded"
+      pure $ Just ("Canvas width exceded actual: " 
+                     <> show config'.width 
+                     <> " requested: "
+                     <> show config.width
+                  )
     else do
       _ <- resizeCanvas renderer config'
       case config'.titling of 
@@ -144,9 +148,11 @@ scaleConfigToDesiredWidth :: AbcTune -> Config -> Int -> Config
 scaleConfigToDesiredWidth abcTune config desiredWidth =
   let 
     justifiedConfig = justifiedScoreConfig (createScore config abcTune) config
-    scaleFactor = (toNumber desiredWidth) / (toNumber justifiedConfig.width)
+    -- fit the score to within 98% of the desired width to avoid margin errors
+    scaleFactor = (0.98 * toNumber desiredWidth) / (toNumber justifiedConfig.width)
     newScale = justifiedConfig.scale * scaleFactor 
-    newWidth = floor $ (toNumber justifiedConfig.width) * scaleFactor 
+    newWidth = desiredWidth
+       -- floor $ (toNumber justifiedConfig.width) * scaleFactor 
     newHeight = floor $ (toNumber justifiedConfig.width) * scaleFactor 
   in 
     justifiedConfig