1GLMULTMATRIX(3G) GLMULTMATRIX(3G)
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6 glMultMatrixd, glMultMatrixf - multiply the current matrix with the
7 specified matrix
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11 void glMultMatrixd( const GLdouble *m )
12 void glMultMatrixf( const GLfloat *m )
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16 m Points to 16 consecutive values that are used as the elements of a
17 4×4 column-major matrix.
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20 glMultMatrix multiplies the current matrix with the one specified using
21 m, and replaces the current matrix with the product.
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23 The current matrix is determined by the current matrix mode (see
24 glMatrixMode). It is either the projection matrix, modelview matrix, or
25 the texture matrix.
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28 If the current matrix is C, and the coordinates to be transformed are,
29 v=(v[0],v[1],v[2],v[3]). Then the current transformation is C×v, or
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32 c[0] c[4] c[8] c[12] v[0]
33 ⎛⎝c[1] c[5] c[9] c[13]⎞⎠×⎛⎝v[1]⎞⎠
34 c[2] c[6] c[10] c[14] v[2]
35 c[3] c[7] c[11] c[15] v[3]
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37 Calling glMultMatrix with an argument of m=m[0],m[1],...,m[15] replaces
38 the current transformation with (C×M)×v, or
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41 c[0] c[4] c[8] c[12] m[0] m[4] m[8] m[12] v[0]
42 ⎛⎝c[1] c[5] c[9] c[13]⎞⎠×⎛⎝m[1] m[5] m[9] m[13]⎞⎠×⎛⎝v[1]⎞⎠
43 c[2] c[6] c[10] c[14] m[2] m[6] m[10] m[14] v[2]
44 c[3] c[7] c[11] c[15] m[3] m[7] m[11] m[15] v[3]
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46 Where '×' denotes matrix multiplication, and v is represented as a 4×1
47 matrix.
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50 While the elements of the matrix may be specified with single or double
51 precision, the GL may store or operate on these values in less than
52 single precision.
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54 In many computer languages 4×4 arrays are represented in row-major
55 order. The transformations just described represent these matrices in
56 column-major order. The order of the multiplication is important. For
57 example, if the current transformation is a rotation, and glMultMatrix
58 is called with a translation matrix, the translation is done directly
59 on the coordinates to be transformed, while the rotation is done on the
60 results of that translation.
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63 GL_INVALID_OPERATION is generated if glMultMatrix is executed between
64 the execution of glBegin and the corresponding execution of glEnd.
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67 glGet with argument GL_MATRIX_MODE
68 glGet with argument GL_COLOR_MATRIX
69 glGet with argument GL_MODELVIEW_MATRIX
70 glGet with argument GL_PROJECTION_MATRIX
71 glGet with argument GL_TEXTURE_MATRIX
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74 glLoadIdentity(3G), glLoadMatrix(3G), glMatrixMode(3G),
75 glPushMatrix(3G)
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80 GLMULTMATRIX(3G)