summaryrefslogtreecommitdiff
path: root/include/SFML/Graphics/Matrix3.inl
blob: 4499415798f521d724079a59d5d281bb138a1b64 (plain)
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
178
179
180
181
182
183
184
185
186
////////////////////////////////////////////////////////////
//
// SFGE - Simple and Fast Multimedia Library
// Copyright (C) 2007-2009 Laurent Gomila (laurent.gom@gmail.com)
//
// This software is provided 'as-is', without any express or implied warranty.
// In no event will the authors be held liable for any damages arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it freely,
// subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented;
//    you must not claim that you wrote the original software.
//    If you use this software in a product, an acknowledgment
//    in the product documentation would be appreciated but is not required.
//
// 2. Altered source versions must be plainly marked as such,
//    and must not be misrepresented as being the original software.
//
// 3. This notice may not be removed or altered from any source distribution.
//
////////////////////////////////////////////////////////////


////////////////////////////////////////////////////////////
/// Default constructor (builds an identity matrix)
////////////////////////////////////////////////////////////
inline Matrix3::Matrix3()
{
    myData[0] = 1.f; myData[4] = 0.f; myData[8]  = 0.f; myData[12] = 0.f;
    myData[1] = 0.f; myData[5] = 1.f; myData[9]  = 0.f; myData[13] = 0.f;
    myData[2] = 0.f; myData[6] = 0.f; myData[10] = 1.f; myData[14] = 0.f;
    myData[3] = 0.f; myData[7] = 0.f; myData[11] = 0.f; myData[15] = 1.f;
}


////////////////////////////////////////////////////////////
/// Construct a matrix from its 9 elements
////////////////////////////////////////////////////////////
inline Matrix3::Matrix3(float a00, float a01, float a02,
                        float a10, float a11, float a12,
                        float a20, float a21, float a22)
{
    myData[0] = a00; myData[4] = a01; myData[8]  = 0.f; myData[12] = a02;
    myData[1] = a10; myData[5] = a11; myData[9]  = 0.f; myData[13] = a12;
    myData[2] = 0.f; myData[6] = 0.f; myData[10] = 1.f; myData[14] = 0.f;
    myData[3] = a20; myData[7] = a21; myData[11] = 0.f; myData[15] = a22;
}


////////////////////////////////////////////////////////////
/// Build a matrix from a set of transformations
////////////////////////////////////////////////////////////
inline void Matrix3::SetFromTransformations(const Vector2f& Center, const Vector2f& Translation, float Rotation, const Vector2f& Scale)
{
    float Angle = Rotation * 3.141592654f / 180.f;
    float Cos   = static_cast<float>(cos(Angle));
    float Sin   = static_cast<float>(sin(Angle));
    float SxCos = Scale.x * Cos;
    float SyCos = Scale.y * Cos;
    float SxSin = Scale.x * Sin;
    float SySin = Scale.y * Sin;
    float Tx    = -Center.x * SxCos - Center.y * SySin + Translation.x;
    float Ty    =  Center.x * SxSin - Center.y * SyCos + Translation.y;

    myData[0] =  SxCos; myData[4] = SySin; myData[8]  = 0.f; myData[12] = Tx;
    myData[1] = -SxSin; myData[5] = SyCos; myData[9]  = 0.f; myData[13] = Ty;
    myData[2] =  0.f;   myData[6] = 0.f;   myData[10] = 1.f; myData[14] = 0.f;
    myData[3] =  0.f;   myData[7] = 0.f;   myData[11] = 0.f; myData[15] = 1.f;
}


////////////////////////////////////////////////////////////
/// Transform a point by the matrix
////////////////////////////////////////////////////////////
inline Vector2f Matrix3::Transform(const Vector2f& Point) const
{
    return Vector2f(myData[0] * Point.x + myData[4] * Point.y + myData[12],
                    myData[1] * Point.x + myData[5] * Point.y + myData[13]);
}


////////////////////////////////////////////////////////////
/// Return the inverse of the matrix
////////////////////////////////////////////////////////////
inline Matrix3 Matrix3::GetInverse() const
{
    // Compute the determinant
    float Det = myData[0] * (myData[15] * myData[5] - myData[7] * myData[13]) -
                myData[1] * (myData[15] * myData[4] - myData[7] * myData[12]) +
                myData[3] * (myData[13] * myData[4] - myData[5] * myData[12]);

    // Compute the inverse if determinant is not zero
    if ((Det < -1E-7f) || (Det > 1E-7f))
    {
        return Matrix3( (myData[15] * myData[5] - myData[7] * myData[13]) / Det,
                       -(myData[15] * myData[4] - myData[7] * myData[12]) / Det,
                        (myData[13] * myData[4] - myData[5] * myData[12]) / Det,
                       -(myData[15] * myData[1] - myData[3] * myData[13]) / Det,
                        (myData[15] * myData[0] - myData[3] * myData[12]) / Det,
                       -(myData[13] * myData[0] - myData[1] * myData[12]) / Det,
                        (myData[7]  * myData[1] - myData[3] * myData[5])  / Det,
                       -(myData[7]  * myData[0] - myData[3] * myData[4])  / Det,
                        (myData[5]  * myData[0] - myData[1] * myData[4])  / Det);
    }
    else
    {
        return Identity;
    }
}


////////////////////////////////////////////////////////////
/// Return the elements of the matrix as a 4x4,
/// in an array of 16 floats
////////////////////////////////////////////////////////////
inline const float* Matrix3::Get4x4Elements() const
{
    return myData;
}


////////////////////////////////////////////////////////////
/// Operator () overloads to access the matrix elements
////////////////////////////////////////////////////////////
inline float Matrix3::operator ()(unsigned int Row, unsigned int Col) const
{
    switch (Row + Col * 3)
    {
        case 0 : return myData[0];
        case 1 : return myData[1];
        case 2 : return myData[3];
        case 3 : return myData[4];
        case 4 : return myData[5];
        case 5 : return myData[7];
        case 6 : return myData[12];
        case 7 : return myData[13];
        case 8 : return myData[15];

        default : return myData[0];
    }
}
inline float& Matrix3::operator ()(unsigned int Row, unsigned int Col)
{
    switch (Row + Col * 3)
    {
        case 0 : return myData[0];
        case 1 : return myData[1];
        case 2 : return myData[3];
        case 3 : return myData[4];
        case 4 : return myData[5];
        case 5 : return myData[7];
        case 6 : return myData[12];
        case 7 : return myData[13];
        case 8 : return myData[15];

        default : return myData[0];
    }
}


////////////////////////////////////////////////////////////
/// Operator * overload to multiply two matrices
////////////////////////////////////////////////////////////
inline Matrix3 Matrix3::operator *(const Matrix3& Mat) const
{
    return Matrix3(myData[0] * Mat.myData[0]  + myData[4] * Mat.myData[1]  + myData[12] * Mat.myData[3],
                   myData[0] * Mat.myData[4]  + myData[4] * Mat.myData[5]  + myData[12] * Mat.myData[7],
                   myData[0] * Mat.myData[12] + myData[4] * Mat.myData[13] + myData[12] * Mat.myData[15],
                   myData[1] * Mat.myData[0]  + myData[5] * Mat.myData[1]  + myData[13] * Mat.myData[3],
                   myData[1] * Mat.myData[4]  + myData[5] * Mat.myData[5]  + myData[13] * Mat.myData[7],
                   myData[1] * Mat.myData[12] + myData[5] * Mat.myData[13] + myData[13] * Mat.myData[15],
                   myData[3] * Mat.myData[0]  + myData[7] * Mat.myData[1]  + myData[15] * Mat.myData[3],
                   myData[3] * Mat.myData[4]  + myData[7] * Mat.myData[5]  + myData[15] * Mat.myData[7],
                   myData[3] * Mat.myData[12] + myData[7] * Mat.myData[13] + myData[15] * Mat.myData[15]);
}


////////////////////////////////////////////////////////////
/// Operator *= overload to multiply-assign two matrices
////////////////////////////////////////////////////////////
inline Matrix3& Matrix3::operator *=(const Matrix3& Mat)
{
    return *this = *this * Mat;
}