340 lines
9.8 KiB
C
340 lines
9.8 KiB
C
/*
|
|
* Cogl
|
|
*
|
|
* An object oriented GL/GLES Abstraction/Utility Layer
|
|
*
|
|
* Copyright (C) 2008,2009 Intel Corporation.
|
|
*
|
|
* This library is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2 of the License, or (at your option) any later version.
|
|
*
|
|
* This library is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
|
|
*
|
|
*
|
|
*
|
|
* Authors:
|
|
* Robert Bragg <robert@linux.intel.com>
|
|
*/
|
|
|
|
#ifndef __COGL_MATRIX_H
|
|
#define __COGL_MATRIX_H
|
|
|
|
#include <glib.h>
|
|
#include "cogl-types.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, texture
|
|
* transforms, and projective transforms. This exposes a utility API that can
|
|
* be used for direct manipulation of these matrices.
|
|
*/
|
|
|
|
typedef struct _CoglMatrix CoglMatrix;
|
|
|
|
/**
|
|
* 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 CoglMatrix 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:
|
|
*
|
|
* |[
|
|
* 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
|
|
* ]|
|
|
*
|
|
* Where w is normally 1
|
|
*
|
|
* <note>You must consider the members of the CoglMatrix structure read only,
|
|
* and all matrix modifications must be done via the cogl_matrix API. This
|
|
* allows Cogl to annotate the matrices internally. Violation of this will give
|
|
* undefined results. If you need to initialize a matrix with a constant other
|
|
* than the identity matrix you can use cogl_matrix_init_from_array().</note>
|
|
*/
|
|
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. */
|
|
float COGL_PRIVATE (inv)[16];
|
|
unsigned long COGL_PRIVATE (type);
|
|
unsigned long COGL_PRIVATE (flags);
|
|
unsigned long COGL_PRIVATE (_padding3);
|
|
};
|
|
|
|
/**
|
|
* cogl_matrix_init_identity:
|
|
* @matrix: A 4x4 transformation matrix
|
|
*
|
|
* Resets matrix to the identity matrix:
|
|
*
|
|
* |[
|
|
* .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;
|
|
* ]|
|
|
*/
|
|
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
|
|
*
|
|
* Multiplies the two supplied matrices together and stores
|
|
* the resulting matrix inside @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
|
|
*
|
|
* Multiplies @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
|
|
*
|
|
* Multiplies @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
|
|
*
|
|
* Multiplies @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);
|
|
|
|
/**
|
|
* cogl_matrix_frustum:
|
|
* @matrix: A 4x4 transformation matrix
|
|
* @left: coord of left vertical clipping plane
|
|
* @right: coord of right vertical clipping plane
|
|
* @bottom: coord of bottom horizontal clipping plane
|
|
* @top: coord of top horizontal clipping plane
|
|
* @z_near: positive distance to near depth clipping plane
|
|
* @z_far: positive distance to far depth clipping plane
|
|
*
|
|
* Multiplies @matrix by the given frustum perspective matrix.
|
|
*/
|
|
void
|
|
cogl_matrix_frustum (CoglMatrix *matrix,
|
|
float left,
|
|
float right,
|
|
float bottom,
|
|
float top,
|
|
float z_near,
|
|
float z_far);
|
|
|
|
/**
|
|
* cogl_matrix_perspective:
|
|
* @matrix: A 4x4 transformation matrix
|
|
* @fov_y: A field of view angle for the Y axis
|
|
* @aspect: The ratio of width to height determining the field of view angle
|
|
* for the x axis.
|
|
* @z_near: The distance to the near clip plane. Never pass 0 and always pass
|
|
* a positive number.
|
|
* @z_far: The distance to the far clip plane. (Should always be positive)
|
|
*
|
|
* Multiplies @matrix by the described perspective matrix
|
|
*
|
|
* <note>You should be careful not to have to great a @z_far / @z_near ratio
|
|
* since that will reduce the effectiveness of depth testing since there wont
|
|
* be enough precision to identify the depth of objects near to each
|
|
* other.</note>
|
|
*/
|
|
void
|
|
cogl_matrix_perspective (CoglMatrix *matrix,
|
|
float fov_y,
|
|
float aspect,
|
|
float z_near,
|
|
float z_far);
|
|
|
|
/**
|
|
* cogl_matrix_ortho:
|
|
* @matrix: A 4x4 transformation matrix
|
|
* @left: The coordinate for the left clipping plane
|
|
* @right: The coordinate for the right clipping plane
|
|
* @bottom: The coordinate for the bottom clipping plane
|
|
* @top: The coordinate for the top clipping plane
|
|
* @z_near: The coordinate for the near clipping plane (may be negative if
|
|
* the plane is behind the viewer)
|
|
* @z_far: The coordinate for the far clipping plane (may be negative if
|
|
* the plane is behind the viewer)
|
|
*
|
|
* Multiplies @matrix by a parallel projection matrix.
|
|
*/
|
|
void
|
|
cogl_matrix_ortho (CoglMatrix *matrix,
|
|
float left,
|
|
float right,
|
|
float bottom,
|
|
float top,
|
|
float z_near,
|
|
float z_far);
|
|
|
|
/**
|
|
* cogl_matrix_init_from_array:
|
|
* @matrix: A 4x4 transformation matrix
|
|
* @array: A linear array of 16 floats (column-major order)
|
|
*
|
|
* Initializes @matrix with the contents of @array
|
|
*/
|
|
void
|
|
cogl_matrix_init_from_array (CoglMatrix *matrix,
|
|
const float *array);
|
|
|
|
/**
|
|
* cogl_matrix_get_array:
|
|
* @matrix: A 4x4 transformation matrix
|
|
*
|
|
* Casts @matrix to a float array which can be directly passed to OpenGL.
|
|
*
|
|
* Return value: a pointer to the float array
|
|
*/
|
|
G_CONST_RETURN float *
|
|
cogl_matrix_get_array (const CoglMatrix *matrix);
|
|
|
|
/**
|
|
* cogl_matrix_equal:
|
|
* @v1: A 4x4 transformation matrix
|
|
* @v2: A 4x4 transformation matrix
|
|
*
|
|
* Compares two matrices to see if they represent the same
|
|
* transformation. Although internally the matrices may have different
|
|
* annotations associated with them and may potentially have a cached
|
|
* inverse matrix these are not considered in the comparison.
|
|
*
|
|
* Since: 1.4
|
|
*/
|
|
gboolean
|
|
cogl_matrix_equal (gconstpointer v1, gconstpointer v2);
|
|
|
|
/**
|
|
* cogl_matrix_get_inverse:
|
|
* @matrix: A 4x4 transformation matrix
|
|
* @inverse: (out): The destination for a 4x4 inverse transformation matrix
|
|
*
|
|
* Gets the inverse transform of a given matrix and uses it to initialize
|
|
* a new #CoglMatrix.
|
|
*
|
|
* <note>Although the first parameter is annotated as const to indicate
|
|
* that the transform it represents isn't modified this function may
|
|
* technically save a copy of the inverse transform within the given
|
|
* #CoglMatrix so that subsequent requests for the inverse transform may
|
|
* avoid costly inversion calculations.</note>
|
|
*
|
|
* Return value: %TRUE if the inverse was successfully calculated or %FALSE
|
|
* for degenerate transformations that can't be inverted (in this case the
|
|
* @inverse matrix will simply be initialized with the identity matrix)
|
|
*
|
|
* Since: 1.2
|
|
*/
|
|
gboolean
|
|
cogl_matrix_get_inverse (const CoglMatrix *matrix,
|
|
CoglMatrix *inverse);
|
|
|
|
/**
|
|
* cogl_matrix_transform_point:
|
|
* @matrix: A 4x4 transformation matrix
|
|
* @x: (inout): The X component of your points position
|
|
* @y: (inout): The Y component of your points position
|
|
* @z: (inout): The Z component of your points position
|
|
* @w: (inout): The W component of your points position
|
|
*
|
|
* Transforms a point whos position is given and returned as four float
|
|
* components.
|
|
*/
|
|
void
|
|
cogl_matrix_transform_point (const CoglMatrix *matrix,
|
|
float *x,
|
|
float *y,
|
|
float *z,
|
|
float *w);
|
|
|
|
G_END_DECLS
|
|
|
|
#endif /* __COGL_MATRIX_H */
|
|
|