1(*
2    Copyright (c) 2001, 2015
3        David C.J. Matthews
4
5    This library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License version 2.1 as published by the Free Software Foundation.
8    
9    This library is distributed in the hope that it will be useful,
10    but WITHOUT ANY WARRANTY; without even the implied warranty of
11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12    Lesser General Public License for more details.
13    
14    You should have received a copy of the GNU Lesser General Public
15    License along with this library; if not, write to the Free Software
16    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
17*)
18
19structure Path :
20  sig
21    type HDC and HRGN
22    type POINT = {x: int, y: int}
23    datatype PointType = datatype Line.PointType
24
25    val AbortPath : HDC -> unit
26    val BeginPath : HDC -> unit
27    val CloseFigure : HDC -> unit
28    val EndPath : HDC -> unit
29    val FillPath : HDC -> unit
30    val FlattenPath : HDC -> unit
31    val GetMiterLimit : HDC -> real
32    val GetPath : HDC -> (PointType * POINT) list
33    val PathToRegion : HDC -> HRGN
34    val SetMiterLimit : HDC * real -> real
35    val StrokeAndFillPath : HDC -> unit
36    val StrokePath : HDC -> unit
37    val WidenPath : HDC -> unit
38
39  end =
40struct
41    local
42        open Foreign Base
43    in
44        type HDC = HDC and POINT = POINT and HRGN = HRGN
45        datatype PointType = datatype Line.PointType
46
47        (* PATHS *)
48        val AbortPath                  = winCall1(gdi "AbortPath") (cHDC) (successState "AbortPath")
49        val BeginPath                  = winCall1(gdi "BeginPath") (cHDC) (successState "BeginPath")
50        val CloseFigure                = winCall1(gdi "CloseFigure") (cHDC) (successState "CloseFigure")
51        val EndPath                    = winCall1(gdi "EndPath") (cHDC) (successState "EndPath")
52        val FillPath                   = winCall1(gdi "FillPath") (cHDC) (successState "FillPath")
53        val FlattenPath                = winCall1(gdi "FlattenPath") (cHDC) (successState "FlattenPath")
54        val PathToRegion               = winCall1(gdi "PathToRegion") (cHDC) cHRGN
55        val StrokeAndFillPath          = winCall1(gdi "StrokeAndFillPath") (cHDC) (successState "StrokeAndFillPath")
56        val StrokePath                 = winCall1(gdi "StrokePath") (cHDC) (successState "StrokePath")
57        val WidenPath                  = winCall1(gdi "WidenPath") (cHDC) (successState "WidenPath")
58        
59        local
60            val getMiterLimit = winCall2(gdi "GetMiterLimit") (cHDC, cStar cFloat) (successState "GetMiterLimit")
61            and setMiterLimit = winCall3(gdi "SetMiterLimit") (cHDC, cFloat, cStar cFloat) (successState "SetMiterLimit")
62        in
63            fun GetMiterLimit hdc = let val v = ref 0.0 in getMiterLimit(hdc, v); !v end
64            and SetMiterLimit(hdc, m) = let val v = ref 0.0 in setMiterLimit(hdc, m, v); !v end
65        end
66
67        local
68            val getPath = winCall4 (gdi "GetPath") (cHDC, cPointer, cPointer, cInt) cInt
69            val {load=fromPt, ctype={size=sizePt, ...}, ...} = breakConversion cPoint
70            val {load=fromTy, ...} = breakConversion GdiBase.cPOINTTYPE
71        in
72            fun GetPath h =
73            let
74                open Memory
75                infix 6 ++
76                (* Passing 0 as the size will retrieve the number of points. *)
77                val count = getPath(h, null, null, 0)
78                val _ = checkResult(count >= 0)
79
80                val ptarr = malloc(Word.fromInt count * sizePt)
81                val farr =  malloc(Word.fromInt count)
82                val _ = getPath(h, ptarr, farr, count) handle ex => (free ptarr; free farr; raise ex)
83                fun getElement n =
84                    (fromTy(farr ++ Word.fromInt n), fromPt(ptarr ++ Word.fromInt n * sizePt))
85            in
86                List.tabulate(count, getElement) before (free ptarr; free farr)
87            end
88        end
89
90    end
91end;
92