modify 'TextBuilder.initEnv' function to take 'startX' and 'startY' parameters, instead of hardcoding the startX/Y inside the function, and change width/height calculations to take these parameters into account

fcore/text-builder/normal-mode-text-builder.sml

@@ -35,7 +35,9 @@ struct
               if searchPos = ~1 then Vector.length searchList else searchPos
 
             val env = Utils.initEnv
-              ( windowWidth
+              ( 5
+              , 5
+              , windowWidth
               , windowHeight
               , floatWindowWidth
               , floatWindowHeight

fcore/text-builder/text-builder-utils.sml

@@ -44,7 +44,9 @@ struct
     }
 
   fun initEnv
-    ( endX
+    ( startX
+    , startY
+    , endX
     , endY
     , floatWindowWidth
     , floatWindowHeight
@@ -53,7 +55,17 @@ struct
     , visualScrollColumn
     , startLine
     ) : env_data =
-    if TC.textLineWidth > endX then
+    let
+      val width = endX - startX
+      val lastLineNumber =
+        let
+          val height = endY - startY
+          val howManyLines = height div TC.ySpace
+        in
+          startLine + howManyLines
+        end
+    in
+      if TC.textLineWidth > width then
         { charR = 0.67
         , charG = 0.51
         , charB = 0.83
@@ -82,17 +94,8 @@ struct
         , startY = 5
 
         , scrollColumnStart = visualScrollColumn
-      , scrollColumnEnd = let val width = endX - 5
-                          in width div TC.xSpace + visualScrollColumn
-                          end
-
-      , lastLineNumber =
-          let
-            val height = endY - 5
-            val howManyLines = height div TC.ySpace
-          in
-            startLine + howManyLines
-          end
+        , scrollColumnEnd = width div TC.xSpace + visualScrollColumn
+        , lastLineNumber = lastLineNumber
 
         , fw = floatWindowWidth
         , fh = floatWindowHeight
@@ -103,7 +106,6 @@ struct
       else
         let
           val startX = (endX - TC.textLineWidth) div 2
-        val finishWidth = startX + TC.textLineWidth
         in
           { charR = 0.67
           , charG = 0.51
@@ -130,18 +132,11 @@ struct
           , highlightZ = 0.05
 
           , startX = startX
-        , startY = 5
+          , startY = startY
 
           , scrollColumnStart = visualScrollColumn
           , scrollColumnEnd = visualScrollColumn + TC.textLineCount
-
-        , lastLineNumber =
-            let
-              val height = endY - 5
-              val howManyLines = height div TC.ySpace
-            in
-              startLine + howManyLines
-            end
+          , lastLineNumber = lastLineNumber
 
           , fw = floatWindowWidth
           , fh = floatWindowHeight
@@ -150,6 +145,7 @@ struct
           , searchLen = searchLen
           }
         end
+    end
 
   (* different functions to make vectors of different things we want to draw. *)
   fun makeCursor (posX, posY, env: env_data) =