mutter/clutter/clutter-util.c
Emmanuele Bassi 22ce4409b3 Add interpolation for matrices
Interpolating between two transformations expressed using a 3D matrix
can be achieved by decomposing the matrices into their transformations
and do a simple numeric interpolation between the initial and final
states, like we do for other data types.

Luckily for us, the CSS Transforms specification from the W3C provides
the decomposition algorithm, using the "unmatrix" code taken from the
book "Graphics Gems II, edited by Jim Arvo".

Once the matrices have been decomposed, we can simply interpolate the
transformations, and re-apply them onto the result matrix, using the
facilities that Clutter provides for interpolating between two known
GTypes.
2012-09-03 20:54:43 +01:00

666 lines
20 KiB
C

/*
* Clutter.
*
* An OpenGL based 'interactive canvas' library.
*
* Authored By Matthew Allum <mallum@openedhand.com>
*
* Copyright (C) 2006 OpenedHand
*
* 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/>.
*
*
*/
/**
* SECTION:clutter-util
* @short_description: Utility functions
*
* Various miscellaneous utilility functions.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <math.h>
#include <glib/gi18n-lib.h>
#include "clutter-debug.h"
#include "clutter-main.h"
#include "clutter-interval.h"
#include "clutter-private.h"
#include "deprecated/clutter-util.h"
/**
* clutter_util_next_p2:
* @a: Value to get the next power
*
* Calculates the nearest power of two, greater than or equal to @a.
*
* Return value: The nearest power of two, greater or equal to @a.
*
* Deprecated: 1.2
*/
gint
clutter_util_next_p2 (gint a)
{
int rval = 1;
while (rval < a)
rval <<= 1;
return rval;
}
/*< private >
* _clutter_gettext:
* @str: a string to localize
*
* Retrieves the localized version of @str, using the Clutter domain
*
* Return value: the translated string
*/
const gchar *
_clutter_gettext (const gchar *str)
{
return g_dgettext (GETTEXT_PACKAGE, str);
}
/* Help macros to scale from OpenGL <-1,1> coordinates system to
* window coordinates ranging [0,window-size]
*/
#define MTX_GL_SCALE_X(x,w,v1,v2) ((((((x) / (w)) + 1.0f) / 2.0f) * (v1)) + (v2))
#define MTX_GL_SCALE_Y(y,w,v1,v2) ((v1) - (((((y) / (w)) + 1.0f) / 2.0f) * (v1)) + (v2))
#define MTX_GL_SCALE_Z(z,w,v1,v2) (MTX_GL_SCALE_X ((z), (w), (v1), (v2)))
void
_clutter_util_fully_transform_vertices (const CoglMatrix *modelview,
const CoglMatrix *projection,
const float *viewport,
const ClutterVertex *vertices_in,
ClutterVertex *vertices_out,
int n_vertices)
{
CoglMatrix modelview_projection;
ClutterVertex4 *vertices_tmp;
int i;
vertices_tmp = g_alloca (sizeof (ClutterVertex4) * n_vertices);
if (n_vertices >= 4)
{
/* XXX: we should find a way to cache this per actor */
cogl_matrix_multiply (&modelview_projection,
projection,
modelview);
cogl_matrix_project_points (&modelview_projection,
3,
sizeof (ClutterVertex),
vertices_in,
sizeof (ClutterVertex4),
vertices_tmp,
n_vertices);
}
else
{
cogl_matrix_transform_points (modelview,
3,
sizeof (ClutterVertex),
vertices_in,
sizeof (ClutterVertex4),
vertices_tmp,
n_vertices);
cogl_matrix_project_points (projection,
3,
sizeof (ClutterVertex4),
vertices_tmp,
sizeof (ClutterVertex4),
vertices_tmp,
n_vertices);
}
for (i = 0; i < n_vertices; i++)
{
ClutterVertex4 vertex_tmp = vertices_tmp[i];
ClutterVertex *vertex_out = &vertices_out[i];
/* Finally translate from OpenGL coords to window coords */
vertex_out->x = MTX_GL_SCALE_X (vertex_tmp.x, vertex_tmp.w,
viewport[2], viewport[0]);
vertex_out->y = MTX_GL_SCALE_Y (vertex_tmp.y, vertex_tmp.w,
viewport[3], viewport[1]);
}
}
/*< private >
* _clutter_util_rectangle_union:
* @src1: first rectangle to union
* @src2: second rectangle to union
* @dest: (out): return location for the unioned rectangle
*
* Calculates the union of two rectangles.
*
* The union of rectangles @src1 and @src2 is the smallest rectangle which
* includes both @src1 and @src2 within it.
*
* It is allowed for @dest to be the same as either @src1 or @src2.
*
* This function should really be in Cairo.
*/
void
_clutter_util_rectangle_union (const cairo_rectangle_int_t *src1,
const cairo_rectangle_int_t *src2,
cairo_rectangle_int_t *dest)
{
int dest_x, dest_y;
dest_x = MIN (src1->x, src2->x);
dest_y = MIN (src1->y, src2->y);
dest->width = MAX (src1->x + src1->width, src2->x + src2->width) - dest_x;
dest->height = MAX (src1->y + src1->height, src2->y + src2->height) - dest_y;
dest->x = dest_x;
dest->y = dest_y;
}
float
_clutter_util_matrix_determinant (const ClutterMatrix *matrix)
{
return matrix->xw * matrix->yz * matrix->zy * matrix->wz
- matrix->xz * matrix->yw * matrix->zy * matrix->wz
- matrix->xw * matrix->yy * matrix->zz * matrix->wz
+ matrix->xy * matrix->yw * matrix->zz * matrix->wz
+ matrix->xz * matrix->yy * matrix->zw * matrix->wz
- matrix->xy * matrix->yz * matrix->zw * matrix->wz
- matrix->xw * matrix->yz * matrix->zx * matrix->wy
+ matrix->xz * matrix->yw * matrix->zx * matrix->wy
+ matrix->xw * matrix->yx * matrix->zz * matrix->wy
- matrix->xx * matrix->yw * matrix->zz * matrix->wy
- matrix->xz * matrix->yx * matrix->zw * matrix->wy
+ matrix->xx * matrix->yz * matrix->zw * matrix->wy
+ matrix->xw * matrix->yy * matrix->zx * matrix->wz
- matrix->xy * matrix->yw * matrix->zx * matrix->wz
- matrix->xw * matrix->yx * matrix->zy * matrix->wz
+ matrix->xx * matrix->yw * matrix->zy * matrix->wz
+ matrix->xy * matrix->yx * matrix->zw * matrix->wz
- matrix->xx * matrix->yy * matrix->zw * matrix->wz
- matrix->xz * matrix->yy * matrix->zx * matrix->ww
+ matrix->xy * matrix->yz * matrix->zx * matrix->ww
+ matrix->xz * matrix->yx * matrix->zy * matrix->ww
- matrix->xx * matrix->yz * matrix->zy * matrix->ww
- matrix->xy * matrix->yx * matrix->zz * matrix->ww
+ matrix->xx * matrix->yy * matrix->zz * matrix->ww;
}
static void
_clutter_util_matrix_transpose_vector4_transform (const ClutterMatrix *matrix,
const ClutterVertex4 *point,
ClutterVertex4 *res)
{
res->x = matrix->xx * point->x
+ matrix->xy * point->y
+ matrix->xz * point->z
+ matrix->xw * point->w;
res->y = matrix->yx * point->x
+ matrix->yy * point->y
+ matrix->yz * point->z
+ matrix->yw * point->w;
res->z = matrix->zx * point->x
+ matrix->zy * point->y
+ matrix->zz * point->z
+ matrix->zw * point->w;
res->w = matrix->wz * point->x
+ matrix->wy * point->w
+ matrix->wz * point->z
+ matrix->ww * point->w;
}
void
_clutter_util_matrix_skew_xy (ClutterMatrix *matrix,
float factor)
{
matrix->yx += matrix->xx * factor;
matrix->yy += matrix->xy * factor;
matrix->yz += matrix->xz * factor;
matrix->yw += matrix->xw * factor;
}
void
_clutter_util_matrix_skew_xz (ClutterMatrix *matrix,
float factor)
{
matrix->zx += matrix->xx * factor;
matrix->zy += matrix->xy * factor;
matrix->zz += matrix->xz * factor;
matrix->zw += matrix->xw * factor;
}
void
_clutter_util_matrix_skew_yz (ClutterMatrix *matrix,
float factor)
{
matrix->zx += matrix->yx * factor;
matrix->zy += matrix->yy * factor;
matrix->zz += matrix->yz * factor;
matrix->zw += matrix->yw * factor;
}
static float
_clutter_util_vertex_length (const ClutterVertex *vertex)
{
return sqrtf (vertex->x * vertex->x + vertex->y * vertex->y + vertex->z * vertex->z);
}
static void
_clutter_util_vertex_normalize (ClutterVertex *vertex)
{
float factor = _clutter_util_vertex_length (vertex);
if (factor == 0.f)
return;
vertex->x /= factor;
vertex->y /= factor;
vertex->z /= factor;
}
static float
_clutter_util_vertex_dot (const ClutterVertex *v1,
const ClutterVertex *v2)
{
return v1->x * v2->x + v1->y * v2->y + v1->z * v2->z;
}
static void
_clutter_util_vertex_cross (const ClutterVertex *v1,
const ClutterVertex *v2,
ClutterVertex *res)
{
res->x = v1->y * v2->z - v2->y * v1->z;
res->y = v1->z * v2->x - v2->z * v1->x;
res->z = v1->x * v2->y - v2->x * v1->y;
}
static void
_clutter_util_vertex_combine (const ClutterVertex *a,
const ClutterVertex *b,
double ascl,
double bscl,
ClutterVertex *res)
{
res->x = (ascl * a->x) + (bscl * b->x);
res->y = (ascl * a->y) + (bscl * b->y);
res->z = (ascl * a->z) + (bscl * b->z);
}
void
_clutter_util_vertex4_interpolate (const ClutterVertex4 *a,
const ClutterVertex4 *b,
double progress,
ClutterVertex4 *res)
{
res->x = a->x + (b->x - a->x) * progress;
res->y = a->y + (b->y - a->y) * progress;
res->z = a->z + (b->z - a->z) * progress;
res->w = a->w + (b->w - a->w) * progress;
}
/*< private >
* clutter_util_matrix_decompose:
* @src: the matrix to decompose
* @scale_p: (out caller-allocates): return location for a vertex containing
* the scaling factors
* @shear_p: (out) (array length=3): return location for an array of 3
* elements containing the skew factors (XY, XZ, and YZ respectively)
* @rotate_p: (out caller-allocates): return location for a vertex containing
* the Euler angles
* @translate_p: (out caller-allocates): return location for a vertex
* containing the translation vector
* @perspective_p: (out caller-allocates: return location for a 4D vertex
* containing the perspective
*
* Decomposes a #ClutterMatrix into the transformations that compose it.
*
* This code is based on the matrix decomposition algorithm as published in
* the CSS Transforms specification by the W3C CSS working group, available
* at http://www.w3.org/TR/css3-transforms/.
*
* The algorithm, in turn, is based on the "unmatrix" method published in
* "Graphics Gems II, edited by Jim Arvo", which is available at:
* http://tog.acm.org/resources/GraphicsGems/gemsii/unmatrix.c
*
* Return value: %TRUE if the decomposition was successful, and %FALSE
* if the matrix is singular
*/
gboolean
_clutter_util_matrix_decompose (const ClutterMatrix *src,
ClutterVertex *scale_p,
float shear_p[3],
ClutterVertex *rotate_p,
ClutterVertex *translate_p,
ClutterVertex4 *perspective_p)
{
CoglMatrix matrix = *src;
CoglMatrix perspective;
ClutterVertex4 vertex_tmp;
ClutterVertex row[3], pdum;
int i, j;
#define XY_SHEAR 0
#define XZ_SHEAR 1
#define YZ_SHEAR 2
#define MAT(m,r,c) ((float *)(m))[(c) * 4 + (r)]
/* normalize the matrix */
if (matrix.ww == 0.f)
return FALSE;
for (i = 0; i < 4; i++)
{
for (j = 0; j < 4; j++)
{
MAT (&matrix, j, i) /= MAT (&matrix, 3, 3);
}
}
/* perspective is used to solve for perspective, but it also provides
* an easy way to test for singularity of the upper 3x3 component
*/
perspective = matrix;
/* transpose */
MAT (&perspective, 3, 0) = 0.f;
MAT (&perspective, 3, 1) = 0.f;
MAT (&perspective, 3, 2) = 0.f;
MAT (&perspective, 3, 3) = 1.f;
if (_clutter_util_matrix_determinant (&perspective) == 0.f)
return FALSE;
if (MAT (&matrix, 3, 0) != 0.f ||
MAT (&matrix, 3, 1) != 0.f ||
MAT (&matrix, 3, 2) != 0.f)
{
CoglMatrix perspective_inv;
ClutterVertex4 p;
vertex_tmp.x = MAT (&matrix, 3, 0);
vertex_tmp.y = MAT (&matrix, 3, 1);
vertex_tmp.z = MAT (&matrix, 3, 2);
vertex_tmp.w = MAT (&matrix, 3, 3);
/* solve the equation by inverting perspective... */
cogl_matrix_get_inverse (&perspective, &perspective_inv);
/* ... and multiplying vertex_tmp by the inverse */
_clutter_util_matrix_transpose_vector4_transform (&perspective_inv,
&vertex_tmp,
&p);
*perspective_p = p;
/* clear the perspective part */
MAT (&matrix, 3, 0) = 0.0f;
MAT (&matrix, 3, 1) = 0.0f;
MAT (&matrix, 3, 2) = 0.0f;
MAT (&matrix, 3, 3) = 1.0f;
}
else
{
/* no perspective */
perspective_p->x = 0.0f;
perspective_p->y = 0.0f;
perspective_p->z = 0.0f;
perspective_p->w = 1.0f;
}
/* translation */
translate_p->x = MAT (&matrix, 0, 3);
MAT (&matrix, 0, 3) = 0.f;
translate_p->y = MAT (&matrix, 1, 3);
MAT (&matrix, 1, 3) = 0.f;
translate_p->z = MAT (&matrix, 2, 3);
MAT (&matrix, 2, 3) = 0.f;
/* scale and shear; we split the upper 3x3 matrix into rows */
for (i = 0; i < 3; i++)
{
row[i].x = MAT (&matrix, i, 0);
row[i].y = MAT (&matrix, i, 1);
row[i].z = MAT (&matrix, i, 2);
}
/* compute scale.x and normalize the first row */
scale_p->x = _clutter_util_vertex_length (&row[0]);
_clutter_util_vertex_normalize (&row[0]);
/* compute XY shear and make the second row orthogonal to the first */
shear_p[XY_SHEAR] = _clutter_util_vertex_dot (&row[0], &row[1]);
_clutter_util_vertex_combine (&row[1], &row[0],
1.0, -shear_p[XY_SHEAR],
&row[1]);
/* compute the Y scale and normalize the second row */
scale_p->y = _clutter_util_vertex_length (&row[1]);
_clutter_util_vertex_normalize (&row[1]);
shear_p[XY_SHEAR] /= scale_p->y;
/* compute XZ and YZ shears, orthogonalize the third row */
shear_p[XZ_SHEAR] = _clutter_util_vertex_dot (&row[0], &row[2]);
_clutter_util_vertex_combine (&row[2], &row[0],
1.0, -shear_p[XZ_SHEAR],
&row[2]);
shear_p[YZ_SHEAR] = _clutter_util_vertex_dot (&row[1], &row[2]);
_clutter_util_vertex_combine (&row[2], &row[1],
1.0, -shear_p[YZ_SHEAR],
&row[2]);
/* get the Z scale and normalize the third row*/
scale_p->z = _clutter_util_vertex_length (&row[2]);
_clutter_util_vertex_normalize (&row[2]);
shear_p[XZ_SHEAR] /= scale_p->z;
shear_p[YZ_SHEAR] /= scale_p->z;
/* at this point, the matrix (inside row[]) is orthonormal.
* check for a coordinate system flip; if the determinant
* is -1, then negate the matrix and scaling factors
*/
_clutter_util_vertex_cross (&row[1], &row[2], &pdum);
if (_clutter_util_vertex_dot (&row[0], &pdum) < 0.f)
{
scale_p->x *= -1.f;
for (i = 0; i < 3; i++)
{
row[i].x *= -1.f;
row[i].y *= -1.f;
row[i].z *= -1.f;
}
}
/* now get the rotations out */
rotate_p->y = asinf (-row[0].z);
if (cosf (rotate_p->y) != 0.f)
{
rotate_p->x = atan2f (row[1].z, row[2].z);
rotate_p->z = atan2f (row[0].y, row[0].x);
}
else
{
rotate_p->x = atan2f (-row[2].x, row[1].y);
rotate_p->z = 0.f;
}
#undef XY_SHEAR
#undef XZ_SHEAR
#undef YZ_SHEAR
#undef MAT
return TRUE;
}
typedef struct
{
GType value_type;
ClutterProgressFunc func;
} ProgressData;
G_LOCK_DEFINE_STATIC (progress_funcs);
static GHashTable *progress_funcs = NULL;
gboolean
_clutter_has_progress_function (GType gtype)
{
const char *type_name = g_type_name (gtype);
if (progress_funcs == NULL)
return FALSE;
return g_hash_table_lookup (progress_funcs, type_name) != NULL;
}
gboolean
_clutter_run_progress_function (GType gtype,
const GValue *initial,
const GValue *final,
gdouble progress,
GValue *retval)
{
ProgressData *pdata;
gboolean res;
G_LOCK (progress_funcs);
if (G_UNLIKELY (progress_funcs == NULL))
{
res = FALSE;
goto out;
}
pdata = g_hash_table_lookup (progress_funcs, g_type_name (gtype));
if (G_UNLIKELY (pdata == NULL))
{
res = FALSE;
goto out;
}
res = pdata->func (initial, final, progress, retval);
out:
G_UNLOCK (progress_funcs);
return res;
}
static void
progress_data_destroy (gpointer data_)
{
g_slice_free (ProgressData, data_);
}
/**
* clutter_interval_register_progress_func: (skip)
* @value_type: a #GType
* @func: a #ClutterProgressFunc, or %NULL to unset a previously
* set progress function
*
* Sets the progress function for a given @value_type, like:
*
* |[
* clutter_interval_register_progress_func (MY_TYPE_FOO,
* my_foo_progress);
* ]|
*
* Whenever a #ClutterInterval instance using the default
* #ClutterInterval::compute_value implementation is set as an
* interval between two #GValue of type @value_type, it will call
* @func to establish the value depending on the given progress,
* for instance:
*
* |[
* static gboolean
* my_int_progress (const GValue *a,
* const GValue *b,
* gdouble progress,
* GValue *retval)
* {
* gint ia = g_value_get_int (a);
* gint ib = g_value_get_int (b);
* gint res = factor * (ib - ia) + ia;
*
* g_value_set_int (retval, res);
*
* return TRUE;
* }
*
* clutter_interval_register_progress_func (G_TYPE_INT, my_int_progress);
* ]|
*
* To unset a previously set progress function of a #GType, pass %NULL
* for @func.
*
* Since: 1.0
*/
void
clutter_interval_register_progress_func (GType value_type,
ClutterProgressFunc func)
{
ProgressData *progress_func;
const char *type_name;
g_return_if_fail (value_type != G_TYPE_INVALID);
type_name = g_type_name (value_type);
G_LOCK (progress_funcs);
if (G_UNLIKELY (progress_funcs == NULL))
progress_funcs = g_hash_table_new_full (NULL, NULL,
NULL,
progress_data_destroy);
progress_func =
g_hash_table_lookup (progress_funcs, type_name);
if (G_UNLIKELY (progress_func))
{
if (func == NULL)
{
g_hash_table_remove (progress_funcs, type_name);
g_slice_free (ProgressData, progress_func);
}
else
progress_func->func = func;
}
else
{
progress_func = g_slice_new (ProgressData);
progress_func->value_type = value_type;
progress_func->func = func;
g_hash_table_replace (progress_funcs,
(gpointer) type_name,
progress_func);
}
G_UNLOCK (progress_funcs);
}