static double
gnome_canvas_item_invoke_point (GnomeCanvasItem *item, double x, double y, int cx, int cy,
GnomeCanvasItem **actual_item)
{
#ifdef HACKISH_AFFINE
double i2w[6], w2c[6], i2c[6], c2i[6];
ArtPoint c, i;
#endif
#ifdef HACKISH_AFFINE
gnome_canvas_item_i2w_affine (item, i2w);
gnome_canvas_w2c_affine (item->canvas, w2c);
art_affine_multiply (i2c, i2w, w2c);
art_affine_invert (c2i, i2c);
c.x = cx;
c.y = cy;
art_affine_point (&i, &c, c2i);
x = i.x;
y = i.y;
#endif
return (* GNOME_CANVAS_ITEM_CLASS (GTK_OBJECT_GET_CLASS (item))->point) (
item, x, y, cx, cy, actual_item);
}
static int affine( Tcl_Interp *interp, int objc, Tcl_Obj * const objv[],
CanvasParams *param, GPtrArray *items, int type )
{
GnoclOption options[] = {
{ "-absolute", GNOCL_BOOL, NULL },
{ "-reverseOrder", GNOCL_BOOL, NULL },
{ NULL }
};
static const int absoluteIdx = 0;
static const int reverseOrderIdx = 1;
guint m;
int noCoords;
int absolute = 0;
int reverse = 0;
if( objc < 4 )
{
/* canvas (affine|move|scale|rotate) tag-or-id coords ?options ? */
Tcl_WrongNumArgs( interp, 3, objv,
"list-of-coordinates ?option val ...?" );
return TCL_ERROR;
}
if( gnoclParseOptions( interp, objc - 3, objv + 3, options ) != TCL_OK )
return TCL_ERROR;
if( options[absoluteIdx].status == GNOCL_STATUS_CHANGED )
absolute = options[absoluteIdx].val.b;
if( options[reverseOrderIdx].status == GNOCL_STATUS_CHANGED )
reverse = options[reverseOrderIdx].val.b;
gnoclClearOptions( options );
if( absolute && reverse )
{
Tcl_SetResult( interp, "Options \"-reverseOrder\" is only valid "
"for relative transformations.", TCL_STATIC );
return TCL_ERROR;
}
if( Tcl_ListObjLength( interp, objv[3], &noCoords ) != TCL_OK )
return TCL_ERROR;
for( m = 0; m < items->len; ++m )
{
Gnocl_CanvasItemInfo *info = GET_INFO( items, m );
int k;
double af[6];
Tcl_Obj *tp;
for( k = 0; k < 6 && k < noCoords; ++k )
{
if( Tcl_ListObjIndex( interp, objv[3], k, &tp ) != TCL_OK )
return TCL_ERROR;
if( Tcl_GetDoubleFromObj( interp, tp, &af[k] ) != TCL_OK )
return TCL_ERROR;
}
/*
x' = af[0] * x + af[2] * y + af[4];
y' = af[1] * x + af[3] * y + af[5];
*/
switch( type )
{
case Affine:
if( noCoords != 6 )
{
Tcl_SetResult( interp,
"size of list-of-coordinates must be 6", TCL_STATIC );
return TCL_ERROR;
}
break;
case Move:
if( noCoords != 2 )
{
Tcl_SetResult( interp, "size of list-of-coordinates must "
"be 2 (delta-x and delta-y)", TCL_STATIC );
return TCL_ERROR;
}
af[4] = af[0];
af[5] = af[1];
af[0] = 1.; af[2] = 0.;
af[1] = 0.; af[3] = 1.;
break;
case Scale:
if( noCoords != 3 && noCoords != 4 )
{
Tcl_SetResult( interp, "size of list-of-coordinates must "
"be 3 or 4 (center, x-scale and y-scale)",
TCL_STATIC );
return TCL_ERROR;
}
else
{
double x = af[0];
double y = af[1];
double scalex = af[2];
double scaley = (noCoords == 4) ? af[3] : scalex;
af[0] = scalex; af[2] = .0; af[4] = x * (1. - scalex);
af[1] = .0; af[3] = scaley; af[5] = y * (1. - scaley);
}
break;
case Rotate:
/* there seems to be some problems with the
canvas without antialiasing and rotating
(bizarre drawings)
*/
if( noCoords != 3 )
{
Tcl_SetResult( interp, "size of list-of-coordinates must "
"be 3 (center and angle)", TCL_STATIC );
return TCL_ERROR;
}
else
{
double x = af[0];
double y = af[1];
double w = af[2];
const double cw = cos( w );
const double sw = sin( w );
af[0] = cw; af[2] = -sw; af[4] = x - x * cw + y * sw;
af[1] = sw; af[3] = cw; af[5] = y - x * sw - y * cw;
}
break;
}
/*
printf( "\nitem: %p absolute: %d\n", info->item, absolute );
printf( "before:\n" );
{
int k;
double af[6];
gnome_canvas_item_i2c_affine( info->item, af );
for( k = 0; k < 6; k += 2 )
printf( "%d: %f ", k, af[k] );
printf( "\n" );
for( k = 1; k < 6; k += 2 )
printf( "%d: %f ", k, af[k] );
printf( "\n" );
}
printf( "affine:\n" );
for( k = 0; k < 6; k += 2 )
printf( "%d: %f ", k, af[k] );
printf( "\n" );
for( k = 1; k < 6; k += 2 )
printf( "%d: %f ", k, af[k] );
printf( "\n" );
*/
if( absolute )
gnome_canvas_item_affine_absolute( info->item, af );
else
{
/* Well, *I* think this is a bug in gnome:
affine_relative should not be the reverse of what one
would expect. Or do I have wrong expectations? */
if( reverse )
gnome_canvas_item_affine_relative( info->item, af );
else
{
double bf[6];
gnome_canvas_item_i2w_affine( info->item, bf );
gnome_canvas_item_affine_absolute( info->item, af );
gnome_canvas_item_affine_relative( info->item, bf );
}
}
}
return TCL_OK;
}
