1 : /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2 : /* ***** BEGIN LICENSE BLOCK *****
3 : * Version: MPL 1.1/GPL 2.0/LGPL 2.1
4 : *
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6 : * 1.1 (the "License"); you may not use this file except in compliance with
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15 : * The Original Code is mozilla.org code.
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17 : * The Initial Developer of the Original Code is
18 : * Netscape Communications Corporation.
19 : * Portions created by the Initial Developer are Copyright (C) 1998
20 : * the Initial Developer. All Rights Reserved.
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22 : * Contributor(s):
23 : * michaelp 09-25-97 1:56pm
24 : *
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26 : * either of the GNU General Public License Version 2 or later (the "GPL"),
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38 :
39 : #ifndef nsTransform2D_h___
40 : #define nsTransform2D_h___
41 :
42 : #include "gfxCore.h"
43 : #include "nsCoord.h"
44 :
45 : class NS_GFX nsTransform2D
46 : {
47 : private:
48 : /**
49 : * This represents the following matrix (note that the order of row/column
50 : * indices is opposite to usual notation)
51 : *
52 : * / m00 0 m20 \
53 : * M = | 0 m11 m21 |
54 : * \ 0 0 1 /
55 : *
56 : * Transformation of a coordinate (x, y) is obtained by setting
57 : * v = (x, y, 1)^T and evaluating M . v
58 : **/
59 :
60 : float m00, m11, m20, m21;
61 :
62 : public:
63 0 : nsTransform2D(void) { m20 = m21 = 0.0f; m00 = m11 = 1.0f; }
64 : nsTransform2D(nsTransform2D *aTransform2D) {
65 : m00 = aTransform2D->m00;
66 : m11 = aTransform2D->m11;
67 : m20 = aTransform2D->m20;
68 : m21 = aTransform2D->m21;
69 : }
70 :
71 0 : ~nsTransform2D(void) { }
72 :
73 : /**
74 : * set this transform to a translation
75 : *
76 : * @param tx, x translation
77 : * @param ty, y translation
78 : **/
79 :
80 0 : void SetToTranslate(float tx, float ty) { m00 = m11 = 1.0f; m20 = tx; m21 = ty; }
81 :
82 : /**
83 : * get the translation portion of this transform
84 : *
85 : * @param pt, Point to return translation values in
86 : **/
87 :
88 : void GetTranslationCoord(nscoord *ptX, nscoord *ptY) const { *ptX = NSToCoordRound(m20); *ptY = NSToCoordRound(m21); }
89 :
90 : /**
91 : * apply matrix to vector
92 : *
93 : * @param pt Point to transform
94 : **/
95 :
96 : void TransformCoord(nscoord *ptX, nscoord *ptY) const;
97 :
98 : /**
99 : * apply matrix to rect
100 : *
101 : * @param rect Rect to transform
102 : **/
103 :
104 : void TransformCoord(nscoord *aX, nscoord *aY, nscoord *aWidth, nscoord *aHeight) const;
105 :
106 : /**
107 : * add a scale to a Transform via x, y pair
108 : *
109 : * @param ptX x value to add as x scale
110 : * @param ptY y value to add as y scale
111 : **/
112 :
113 : void AddScale(float ptX, float ptY) { m00 *= ptX; m11 *= ptY; }
114 :
115 : /**
116 : * Set the scale (overriding any previous calls to AddScale, but leaving
117 : * any existing translation).
118 : *
119 : * @param ptX x value to add as x scale
120 : * @param ptY y value to add as y scale
121 : **/
122 :
123 0 : void SetScale(float ptX, float ptY) { m00 = ptX; m11 = ptY; }
124 : };
125 :
126 : #endif
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