Manpages OpenGL - glMultTransposeMatrix

Page OpenGL 2.X --- Revenir au moteur de recherche

Name

glMultTransposeMatrix — multiply the current matrix with the specified row-major ordered matrix

C Specification

void glMultTransposeMatrixd( const GLdouble * m);

void glMultTransposeMatrixf( const GLfloat * m);

Parameters

m: Points to 16 consecutive values that are used as the elements of a 4 × 4 row-major matrix.

Description

glMultTransposeMatrix multiplies the current matrix with the one specified using m, and replaces the current matrix with the product.

The current matrix is determined by the current matrix mode (see glMatrixMode). It is either the projection matrix, modelview matrix, or the texture matrix.

Examples

If the current matrix is C and the coordinates to be transformed are v = v ⁡ 0 v ⁡ 1 v ⁡ 2 v ⁡ 3 , then the current transformation is C × v , or

c ⁡ 0 c ⁡ 4 c ⁡ 8 c ⁡ 12 c ⁡ 1 c ⁡ 5 c ⁡ 9 c ⁡ 13 c ⁡ 2 c ⁡ 6 c ⁡ 10 c ⁡ 14 c ⁡ 3 c ⁡ 7 c ⁡ 11 c ⁡ 15 × v ⁡ 0 v ⁡ 1 v ⁡ 2 v ⁡ 3

Calling glMultTransposeMatrix with an argument of m ⁡ 16 = m ⁡ 0 m ⁡ 1 ... m ⁡ 15 replaces the current transformation with C × M × v , or

c ⁡ 0 c ⁡ 4 c ⁡ 8 c ⁡ 12 c ⁡ 1 c ⁡ 5 c ⁡ 9 c ⁡ 13 c ⁡ 2 c ⁡ 6 c ⁡ 10 c ⁡ 14 c ⁡ 3 c ⁡ 7 c ⁡ 11 c ⁡ 15 × m ⁡ 0 m ⁡ 1 m ⁡ 2 m ⁡ 3 m ⁡ 4 m ⁡ 5 m ⁡ 6 m ⁡ 7 m ⁡ 8 m ⁡ 9 m ⁡ 10 m ⁡ 11 m ⁡ 12 m ⁡ 13 m ⁡ 14 m ⁡ 15 × v ⁡ 0 v ⁡ 1 v ⁡ 2 v ⁡ 3

Where v is represented as a 4 × 1 matrix.

Calling glMultTransposeMatrix with matrix M is identical in operation to glMultMatrix with M T , where T represents the transpose.

Notes

glMultTransposeMatrix is available only if the GL version is 1.3 or greater.

While the elements of the matrix may be specified with single or double precision, the GL may store or operate on these values in less-than-single precision.

The order of the multiplication is important. For example, if the current transformation is a rotation, and glMultTransposeMatrix is called with a translation matrix, the translation is done directly on the coordinates to be transformed, while the rotation is done on the results of that translation.

Errors

GL_INVALID_OPERATION is generated if glMultTransposeMatrix is executed between the execution of glBegin and the corresponding execution of glEnd.

Associated Gets

glGet with argument GL_MATRIX_MODE

glGet with argument GL_COLOR_MATRIX

glGet with argument GL_MODELVIEW_MATRIX

glGet with argument GL_PROJECTION_MATRIX

glGet with argument GL_TEXTURE_MATRIX