Files
sml-projects/fcore/text-builder.sml

267 lines
9.7 KiB
Standard ML

signature TEXT_BUILDER =
sig
(* Prerequisite: LineGap is moved to requested line first. *)
val build: int * int * LineGap.t * int * int
-> MailboxType.t list
end
structure TextBuilder :> TEXT_BUILDER =
struct
open TextConstants
fun accToDrawMsg (textAcc, cursorAcc) =
let
open MailboxType
open DrawMsg
val textAcc = Vector.concat textAcc
val cursorAcc = Vector.concat cursorAcc
val textMsg = REDRAW_TEXT textAcc
val cursorMsg = REDRAW_CURSOR cursorAcc
in
[DRAW textMsg, DRAW cursorMsg]
end
fun buildCursor (posX, posY, fWindowWidth, fWindowHeight, r, g, b) =
let
val left = posX + 9
val left = Real32.fromInt left
val right = left + 12.0
val top = Real32.fromInt posY
val bottom = top + fontSize + 2.0
val halfHeight = fWindowHeight / 2.0
val top = (~(top - halfHeight)) / halfHeight
val bottom = (~(bottom - halfHeight)) / halfHeight
val halfWidth = fWindowWidth / 2.0
val left = (left - halfWidth) / halfWidth
val right = (right - halfWidth) / halfWidth
val vec =
#[ left, top, r, g, b
, right, top, r, g, b
, left, bottom, r, g, b
, left, bottom, r, g, b
, right, bottom, r, g, b
, right, top, r, g, b
]
in
[vec]
end
(* builds text from a string with char-wrap.
* char-wrap is a similar concept to word-wrap,
* but it breaks on character in the middle of a word.
*
* Will likely want multiple versions of these two mutually recursive
* functions for each selection and cursor type:
* cursor over an individual character,
* range selection where multiple characters are selected, etc.
*
* Todo:
* - Possibly add visual horizontal indentation when char-wrap occurs
* on an indented line *)
(* same as buildTextStringAfterCursor, except this keeps track of absolute
* index and cursor pos too *)
fun buildTextString
( pos, str, acc, posX, posY, startX
, windowWidth, windowHeight, fWindowWidth, fWindowHeight
, r, g, b, tl, absIdx, cursorPos, cursorAcc, hr, hg, hb
) =
if pos < String.size str then
case String.sub (str, pos) of
#" " =>
(* if inside cursor, then create cursorAcc;
* else, just skip as usual *)
if absIdx <> cursorPos then
(* not in cursur *)
buildTextString
( pos + 1, str, acc, posX + xSpace, posY, startX
, windowWidth, windowHeight, fWindowWidth, fWindowHeight
, r, g, b, tl, absIdx + 1, cursorPos, cursorAcc, hr, hg, hb
)
else
(* in cursor *)
let
val cursorAcc = buildCursor (posX, posY, fWindowWidth, fWindowHeight, r, g ,b)
in
buildTextString
( pos + 1, str, acc, posX + xSpace, posY, startX
, windowWidth, windowHeight, fWindowWidth, fWindowHeight
, r, g, b, tl, absIdx + 1, cursorPos, cursorAcc, hr, hg, hb
)
end
| #"\n" =>
if posY + ySpace < windowHeight then
if absIdx <> cursorPos then
(* not in cursor position, so iterate like normal *)
buildTextString
( pos + 1, str, acc, startX, posY + ySpace, startX
, windowWidth, windowHeight, fWindowWidth, fWindowHeight
, r, g, b, tl, absIdx + 1, cursorPos, cursorAcc, hr, hg, hb
)
else
(* in cursor position, so build cursorAcc *)
if pos = String.size str - 1 andalso tl = [] then
(* if we are at end of lineGap, we want to build cursorAcc
* at different coordinates than usual *)
let
val cursorAcc =
buildCursor (startX, posY + ySpace, fWindowWidth, fWindowHeight, r, g, b)
in
accToDrawMsg (acc, cursorAcc)
end
else
let
val cursorAcc = buildCursor (posX, posY, fWindowWidth, fWindowHeight, r, g ,b)
in
buildTextString
( pos + 1, str, acc, startX, posY + ySpace, startX
, windowWidth, windowHeight, fWindowWidth, fWindowHeight
, r, g, b, tl, absIdx + 1, cursorPos, cursorAcc, hr, hg, hb
)
end
else
accToDrawMsg (acc, cursorAcc)
| chr =>
let
val chrFun = Vector.sub (CozetteAscii.asciiTable, Char.ord chr)
in
if absIdx <> cursorPos then
(* not equal to cursor *)
if posX + xSpace < windowWidth then
let
val chrVec = chrFun
(posX, posY, fontSize, fontSize, fWindowWidth, fWindowHeight, r, g, b)
val acc = chrVec :: acc
in
buildTextString
( pos + 1, str, acc, posX + xSpace, posY, startX
, windowWidth, windowHeight, fWindowWidth, fWindowHeight
, r, g, b, tl, absIdx + 1, cursorPos, cursorAcc, hr, hg, hb
)
end
else if posY + ySpace < windowHeight then
let
val chrVec = chrFun
( startX, posY + ySpace, fontSize, fontSize
, fWindowWidth, fWindowHeight
, r, g, b
)
val acc = chrVec :: acc
in
buildTextString
( pos + 1, str, acc, startX + xSpace, posY + ySpace, startX
, windowWidth, windowHeight, fWindowWidth, fWindowHeight
, r, g, b, tl, absIdx + 1, cursorPos, cursorAcc, hr, hg, hb
)
end
else
accToDrawMsg (acc, cursorAcc)
else
(* equal to cursor *)
let
val cursorAcc = buildCursor (posX, posY, fWindowWidth, fWindowHeight, r, g ,b)
in
if posX + xSpace < windowWidth then
let
val chrVec = chrFun
( posX, posY, fontSize, fontSize
, fWindowWidth, fWindowHeight
, hr, hg, hb
)
val acc = chrVec :: acc
in
(* can start building after cursor now,
* since cursor was built *)
buildTextString
( pos + 1, str, acc, posX + xSpace, posY, startX
, windowWidth, windowHeight, fWindowWidth, fWindowHeight
, r, g, b, tl, absIdx + 1, cursorPos, cursorAcc, hr, hg, hb
)
end
else if posY + ySpace < windowHeight then
let
val chrVec = chrFun
( startX, posY + ySpace, fontSize, fontSize
, fWindowWidth, fWindowHeight
, hr, hg, hb
)
val acc = chrVec :: acc
in
(* can start building after cursor now,
* since cursor was built *)
buildTextString
( pos + 1, str, acc, startX + xSpace, posY + ySpace, startX
, windowWidth, windowHeight, fWindowWidth, fWindowHeight
, r, g, b, tl, absIdx + 1, cursorPos, cursorAcc, hr, hg, hb
)
end
else
accToDrawMsg (acc, cursorAcc)
end
end
else
(* we have built cursor now, so can call after-cursor function
* to build rest of text *)
case tl of
hd :: tl =>
buildTextString
( 0, hd, acc, posX, posY, startX
, windowWidth, windowHeight, fWindowWidth, fWindowHeight
, r, g, b, tl, absIdx, cursorPos, cursorAcc, hr, hg, hb
)
| [] =>
accToDrawMsg (acc, cursorAcc)
fun build
(startLine, cursorPos, lineGap: LineGap.t, windowWidth, windowHeight) =
let
val {rightStrings, rightLines, line = curLine, idx = curIdx, ...} = lineGap
in
case (rightStrings, rightLines) of
(rStrHd :: rStrTl, rLnHd :: _) =>
let
(* get index of line to start building from *)
val startIdx =
if startLine > curLine then
let
val lnPos = startLine - curLine - 1
val startIdx = Vector.sub (rLnHd, lnPos)
in
if
String.sub (rStrHd, startIdx) = #"\r"
andalso startIdx < String.size rStrHd - 1
andalso String.sub (rStrHd, startIdx + 1) = #"\n"
then
(* handle \r\n pair *)
startIdx + 2
else startIdx + 1
end
else
0
val absIdx = curIdx + startIdx
in
buildTextString
( startIdx, rStrHd, []
, 5, 5, 5
, windowWidth, windowHeight
, Real32.fromInt windowWidth, Real32.fromInt windowHeight
, 0.67, 0.51, 0.83
, rStrTl, absIdx, cursorPos, []
, 0.211, 0.219, 0.25
)
end
| (_, _) =>
(* requested line goes beyond the buffer,
* so just return empty list as there is nothig
* else we can do. *)
[]
end
end