-
Notifications
You must be signed in to change notification settings - Fork 3
/
MagnGlassWin.pas
177 lines (154 loc) · 4.92 KB
/
MagnGlassWin.pas
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
unit MagnGlassWin;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics,
Controls, Forms, Dialogs, ExtCtrls, StdCtrls, ComCtrls,
GeoTypes, GeoLocLines, GeoImage;
type
TMyMagnGlassWin = class(TForm)
Panel1: TPanel;
PaintBox1: TPaintBox;
Label1: TLabel;
Label2: TLabel;
procedure PaintBox1Paint(Sender: TObject);
procedure FormClose(Sender: TObject; var Action: TCloseAction);
private
hLen : Integer; // half of the length of one side of the quadratic PaintBox
Scale : Double; // actual magnification value
MyMainWin : TForm;
MyCenterPt: TGPoint;
MyFunktion: TGFunktion;
MyDrawing : TGeoObjListe;
MyBuffer : TBitMap;
procedure ShowSlopeTriangles(h: Double);
procedure ShowSecantSlopes(h: Double);
public
constructor CreateWD(iOwner: TComponent; iCenterPt: TGPoint;
iMGWin_dx, iMGWin_dy: Integer);
procedure RefreshBuffer;
end;
implementation
uses MainWin, Declar, GlobVars, Utility, Math;
{$R *.dfm}
constructor TMyMagnGlassWin.CreateWD(iOwner: TComponent; iCenterPt: TGPoint;
iMGWin_dx, iMGWin_dy: Integer);
begin
Inherited Create(iOwner);
hLen := 150;
Scale := 1;
MyMainWin := iOwner as TForm;
MyDrawing := (MyMainWin as THauptFenster).Drawing;
MyCenterPt := iCenterPt;
MyFunktion := MyCenterPt.Parent[0];
MyBuffer := TBitMap.Create();
Self.Left := MyMainWin.Left + iMGWin_dx;
Self.Top := MyMainWin.Top + iMGWin_dy;
MyBuffer.SetSize(2*hLen, 2*hLen);
RefreshBuffer;
end;
procedure TMyMagnGlassWin.FormClose(Sender: TObject; var Action: TCloseAction);
begin
FreeAndNil(MyBuffer);
With (MyMainWin as THauptFenster) do begin
Drawing.FreeObject(MagnGlassFrame);
MagnGlassFrame := Nil;
MagnGlassWin := Nil;
RefreshSpecialImageButtons;
Invalidate;
end;
Action := caFree;
end;
procedure TMyMagnGlassWin.PaintBox1Paint(Sender: TObject);
begin
PaintBox1.Canvas.Draw(0, 0, MyBuffer);
end;
procedure TMyMagnGlassWin.RefreshBuffer;
var h, wh, relScale : Double;
begin
h := (MyMainWin as THauptfenster).MagnGlassFrame.h;
Label2.Caption := 'h = ' + Float2Str(h, 6) + ' cm';
// Vergrößerung muss aktuelle Auflösung (ppcm!) berücksichtigen!
// "hLen - 10" statt nur "hLen" verlagert die Punkte Ali und
// Are etwas ins Innere der PaintBox.
relScale := (hLen - 10) / act_PixelPerXcm / h;
Label1.Caption := 'Vergrößerung: ' + Float2Str(relScale, 2) + '-fach';
with MyBuffer.Canvas do begin
Pen.Color := clBlack;
Pen.Width := 3;
Brush.Color := clWhite;
Rectangle(Rect(0, 0, 2 * hlen, 2 * hlen));
Pen.Color := clGray;
Brush.Color := LightCol(clYellow, 0.25);
Rectangle(Rect(10, 10, 2 * hlen - 10, 2 * hlen - 10));
end;
With (MyMainWin as THauptfenster) do begin
MagnGlassFrame.MGWin_dx := Self.Left - MyMainWin.Left;
MagnGlassFrame.MGWin_dy := Self.Top - MyMainWin.Top;
if MagnGlassFrame.ShowSecants then begin
ShowSlopeTriangles(h);
ShowSecantSlopes(h);
end;
end;
wh := hlen / act_PixelPerXcm / relScale;
MyDrawing.ExportZoomed_To(MyBuffer.Canvas,
MyCenterPt.X - wh, MyCenterPt.Y + wh,
MyCenterPt.X + wh, MyCenterPt.Y - wh, relScale);
Invalidate;
end;
//========== Private Internal Helpers ================================ //
procedure TMyMagnGlassWin.ShowSlopeTriangles(h: Double);
var pts : Array of TPoint;
dy : Double;
du : Integer;
begin
with (MyMainWin as THauptfenster).MagnGlassFrame do
dy := getFramePt(true).Y - getCenterPt.Y;
du := Round((hlen - 10) / h * dy);
SetLength(pts, 3);
pts[0] := Point(hlen, hlen );
pts[1] := Point(13, hlen );
pts[2] := Point(13, hlen - du);
With MyBuffer.Canvas do begin
Pen.Color := clGray;
Brush.Color := clGray;
Brush.Style := bsDiagCross;
Polygon(pts);
end;
with (MyMainWin as THauptfenster).MagnGlassFrame do
dy := getFramePt(false).Y - getCenterPt.Y;
du := Round((hlen - 10) / h * dy);
pts[1] := Point(286, hlen);
pts[2] := Point(286, hlen - du);
MyBuffer.Canvas.Polygon(pts);
end;
procedure TMyMagnGlassWin.ShowSecantSlopes(h: Double);
var dy1, dy2,
ms1, ms2 : Double;
s1, s2 : String;
function f(x : Double): Double;
var y : Double;
begin
MyFunktion.GetFunctionValue(x, y);
Result := y;
end;
begin
dy1 := MyCenterPt.Y - f(MyCenterPt.X - h);
dy2 := f(MyCenterPt.X + h) - MyCenterPt.Y;
ms1 := dy1 / h;
ms2 := dy2 / h;
With MyBuffer.Canvas do begin
Font.Color := clBlack;
Brush.Style := bsClear;
s1 := 'm1 = ' + FloatToStrF(ms1, ffFixed, 8, 4);
if ms1 > 0 then
TextOut(30, hlen - 30, s1)
else
TextOut(30, hlen + 15, s1);
s2 := 'm2 = ' + FloatToStrF(ms2, ffFixed, 8, 4);
if ms2 > 0 then
TextOut(hlen + 30, hlen + 15, s2)
else
TextOut(hlen + 30, hlen - 30, s2);
end;
end;
end.