mirror of
https://github.com/brl/mutter.git
synced 2024-11-30 03:50:47 -05:00
63047e1907
Adds a few more gtk-doc notes to cogl-matrix.h, and adds a new section to cogl-sections.txt
147 lines
3.6 KiB
C
147 lines
3.6 KiB
C
#ifndef __COGL_MATRIX_H
|
|
#define __COGL_MATRIX_H
|
|
|
|
#include <glib.h>
|
|
|
|
G_BEGIN_DECLS
|
|
|
|
/**
|
|
* SECTION:cogl-matrix
|
|
* @short_description: Fuctions for initializing and manipulating 4x4
|
|
* matrices.
|
|
*
|
|
* Matrices are used in Cogl to describe affine model-view transforms and
|
|
* texture transforms, and projective transforms. This exposes a utility API
|
|
* that can be used for direct manipulation of these matrices.
|
|
*/
|
|
|
|
|
|
/**
|
|
* CoglMatrix:
|
|
*
|
|
* A CoglMatrix holds a 4x4 transform matrix. This is a single precision,
|
|
* column-major matrix which means it is compatible with what OpenGL expects.
|
|
*
|
|
* A CoglMatix can represent transforms such as, rotations, scaling,
|
|
* translation, sheering, and linear projections. You can combine these
|
|
* transforms by multiplying multiple matrices in the order you want them
|
|
* applied.
|
|
*
|
|
* The transformation of a vertex (x, y, z, w) by a CoglMatrix is given by:
|
|
* <programlisting>
|
|
* x_new = xx * x + xy * y + xz * z + xw * w
|
|
* y_new = yx * x + yy * y + yz * z + yw * w
|
|
* z_new = zx * x + zy * y + zz * z + zw * w
|
|
* w_new = wx * x + wy * y + wz * z + ww * w
|
|
* </programlisting>
|
|
* Where w is normally 1
|
|
*/
|
|
typedef struct _CoglMatrix {
|
|
/* column 0 */
|
|
float xx;
|
|
float yx;
|
|
float zx;
|
|
float wx;
|
|
|
|
/* column 1 */
|
|
float xy;
|
|
float yy;
|
|
float zy;
|
|
float wy;
|
|
|
|
/* column 2 */
|
|
float xz;
|
|
float yz;
|
|
float zz;
|
|
float wz;
|
|
|
|
/* column 3 */
|
|
float xw;
|
|
float yw;
|
|
float zw;
|
|
float ww;
|
|
|
|
/*< private >*/
|
|
|
|
/* Note: we may want to extend this later with private flags
|
|
* and a cache of the inverse transform matrix. */
|
|
} CoglMatrix;
|
|
|
|
/**
|
|
* cogl_matrix_init_identity:
|
|
* @matrix: A 4x4 transformation matrix
|
|
*
|
|
* Resets matrix to the identity matrix:
|
|
* <programlisting>
|
|
* .xx=1; .xy=0; .xz=0; .xw=0;
|
|
* .yx=0; .yy=1; .yz=0; .yw=0;
|
|
* .zx=0; .zy=0; .zz=1; .zw=0;
|
|
* .wx=0; .wy=0; .wz=0; .ww=1;
|
|
* </programlisting>
|
|
*/
|
|
void cogl_matrix_init_identity (CoglMatrix *matrix);
|
|
|
|
/**
|
|
* cogl_matrix_multiply:
|
|
* @result: The address of a 4x4 matrix to store the result in
|
|
* @a: A 4x4 transformation matrix
|
|
* @b: A 4x4 transformation matrix
|
|
*
|
|
* This function multiples the two supplied matricies together and stores
|
|
* the result in #result
|
|
*/
|
|
void cogl_matrix_multiply (CoglMatrix *result,
|
|
const CoglMatrix *a,
|
|
const CoglMatrix *b);
|
|
|
|
/**
|
|
* cogl_matrix_rotate:
|
|
* @matrix: A 4x4 transformation matrix
|
|
* @angle: The angle you want to rotate in degrees
|
|
* @x: X component of your rotation vector
|
|
* @y: Y component of your rotation vector
|
|
* @z: Z component of your rotation vector
|
|
*
|
|
* This function multiples your matrix with a rotation matrix that applies
|
|
* a rotation of #angle degrees around the specified 3D vector.
|
|
*/
|
|
void cogl_matrix_rotate (CoglMatrix *matrix,
|
|
float angle,
|
|
float x,
|
|
float y,
|
|
float z);
|
|
|
|
/* cogl_matrix_translate:
|
|
* @matrix: A 4x4 transformation matrix
|
|
* @x: The X translation you want to apply
|
|
* @y: The Y translation you want to apply
|
|
* @z: The Z translation you want to apply
|
|
*
|
|
* This function multiples your matrix with a transform matrix that translates
|
|
* along the X, Y and Z axis.
|
|
*/
|
|
void cogl_matrix_translate (CoglMatrix *matrix,
|
|
float x,
|
|
float y,
|
|
float z);
|
|
|
|
/**
|
|
* cogl_matrix_scale:
|
|
* @matrix: A 4x4 transformation matrix
|
|
* @sx: The X scale factor
|
|
* @sy: The Y scale factor
|
|
* @sz: The Z scale factor
|
|
*
|
|
* This function multiples your matrix with a transform matrix that scales
|
|
* along the X, Y and Z axis.
|
|
*/
|
|
void cogl_matrix_scale (CoglMatrix *matrix,
|
|
float sx,
|
|
float sy,
|
|
float sz);
|
|
|
|
G_END_DECLS
|
|
|
|
#endif /* __COGL_MATRIX_H */
|
|
|