diff options
Diffstat (limited to 'eel/eel-canvas-util.h')
| -rw-r--r-- | eel/eel-canvas-util.h | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/eel/eel-canvas-util.h b/eel/eel-canvas-util.h new file mode 100644 index 00000000..e4484cde --- /dev/null +++ b/eel/eel-canvas-util.h @@ -0,0 +1,110 @@ +/* + * Copyright (C) 1997, 1998, 1999, 2000 Free Software Foundation + * All rights reserved. + * + * This file is part of the Mate Library. + * + * The Mate Library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Library General Public License as + * published by the Free Software Foundation; either version 2 of the + * License, or (at your option) any later version. + * + * The Mate 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 + * Library General Public License for more details. + * + * You should have received a copy of the GNU Library General Public + * License along with the Mate Library; see the file COPYING.LIB. If not, + * write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 02111-1307, USA. + */ +/* + @NOTATION@ + */ +/* Miscellaneous utility functions for the EelCanvas widget + * + * EelCanvas is basically a port of the Tk toolkit's most excellent canvas widget. Tk is + * copyrighted by the Regents of the University of California, Sun Microsystems, and other parties. + * + * Author: Federico Mena <[email protected]> + */ + +#ifndef EEL_CANVAS_UTIL_H +#define EEL_CANVAS_UTIL_H + + +#ifdef __cplusplus +extern "C" { +#endif + + + /* This structure defines an array of points. X coordinates are stored in the even-numbered + * indices, and Y coordinates are stored in the odd-numbered indices. num_points indicates the + * number of points, so the array is 2*num_points elements big. + */ + typedef struct + { + double *coords; + int num_points; + int ref_count; + } EelCanvasPoints; + + + /* Allocate a new EelCanvasPoints structure with enough space for the specified number of points */ + EelCanvasPoints *eel_canvas_points_new (int num_points); + + /* Increate ref count */ + EelCanvasPoints *eel_canvas_points_ref (EelCanvasPoints *points); +#define eel_canvas_points_unref eel_canvas_points_free + + /* Decrease ref count and free structure if it has reached zero */ + void eel_canvas_points_free (EelCanvasPoints *points); + + /* Given three points forming an angle, compute the coordinates of the inside and outside points of + * the mitered corner formed by a line of a given width at that angle. + * + * If the angle is less than 11 degrees, then FALSE is returned and the return points are not + * modified. Otherwise, TRUE is returned. + */ + int eel_canvas_get_miter_points (double x1, double y1, double x2, double y2, double x3, double y3, + double width, + double *mx1, double *my1, double *mx2, double *my2); + + /* Compute the butt points of a line segment. If project is FALSE, then the results are as follows: + * + * -------------------* (bx1, by1) + * | + * (x1, y1) *------------------* (x2, y2) + * | + * -------------------* (bx2, by2) + * + * that is, the line is not projected beyond (x2, y2). If project is TRUE, then the results are as + * follows: + * + * -------------------* (bx1, by1) + * (x2, y2) | + * (x1, y1) *-------------* | + * | + * -------------------* (bx2, by2) + */ + void eel_canvas_get_butt_points (double x1, double y1, double x2, double y2, + double width, int project, + double *bx1, double *by1, double *bx2, double *by2); + + /* Calculate the distance from a polygon to a point. The polygon's X coordinates are in the even + * indices of the poly array, and the Y coordinates are in the odd indices. + */ + double eel_canvas_polygon_to_point (double *poly, int num_points, double x, double y); + + + void eel_canvas_item_reset_bounds (EelCanvasItem *item); + + /* Sets the bbox to the new value, requesting full repaint. */ + void eel_canvas_update_bbox (EelCanvasItem *item, int x1, int y1, int x2, int y2); + +#ifdef __cplusplus +} +#endif + +#endif |