blender-archive/source/blender/blenlib/intern/rct.c

/*
 * ***** BEGIN GPL LICENSE BLOCK *****
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
 * All rights reserved.
 *
 * The Original Code is: all of this file.
 *
 * Contributor(s): none yet.
 *
 * ***** END GPL LICENSE BLOCK *****
 *
 */

/** \file blender/blenlib/intern/rct.c
 *  \ingroup bli
 *
 * A minimalist lib for functions doing stuff with rectangle structs.
 */

#include <stdio.h>
#include <math.h>

#include "DNA_vec_types.h"
#include "BLI_rect.h"

int BLI_rcti_is_empty(rcti *rect)
{
	return ((rect->xmax <= rect->xmin) || (rect->ymax <= rect->ymin));
}

int BLI_rctf_is_empty(rctf *rect)
{
	return ((rect->xmax <= rect->xmin) || (rect->ymax <= rect->ymin));
}

int BLI_in_rcti(rcti *rect, int x, int y)
{
	if (x < rect->xmin) return 0;
	if (x > rect->xmax) return 0;
	if (y < rect->ymin) return 0;
	if (y > rect->ymax) return 0;
	return 1;
}

int BLI_in_rctf(rctf *rect, float x, float y)
{
	if (x < rect->xmin) return 0;
	if (x > rect->xmax) return 0;
	if (y < rect->ymin) return 0;
	if (y > rect->ymax) return 0;
	return 1;
}

/* based closely on 'isect_line_line_v2_int', but in modified so corner cases are treated as intersections */
static int isect_segments(const int v1[2], const int v2[2], const int v3[2], const int v4[2])
{
	const double div = (double)((v2[0] - v1[0]) * (v4[1] - v3[1]) - (v2[1] - v1[1]) * (v4[0] - v3[0]));
	if (div == 0.0f) {
		return 1; /* co-linear */
	}
	else {
		const double labda = (double)((v1[1] - v3[1]) * (v4[0] - v3[0]) - (v1[0] - v3[0]) * (v4[1] - v3[1])) / div;
		const double mu    = (double)((v1[1] - v3[1]) * (v2[0] - v1[0]) - (v1[0] - v3[0]) * (v2[1] - v1[1])) / div;
		return (labda >= 0.0f && labda <= 1.0f && mu >= 0.0f && mu <= 1.0f);
	}
}

int BLI_segment_in_rcti(rcti *rect, int s1[2], int s2[2])
{
	/* first do outside-bounds check for both points of the segment */
	if (s1[0] < rect->xmin && s2[0] < rect->xmin) return 0;
	if (s1[0] > rect->xmax && s2[0] > rect->xmax) return 0;
	if (s1[1] < rect->ymin && s2[1] < rect->ymin) return 0;
	if (s1[1] > rect->ymax && s2[1] > rect->ymax) return 0;

	/* if either points intersect then we definetly intersect */
	if (BLI_in_rcti(rect, s1[0], s1[1]) || BLI_in_rcti(rect, s2[0], s2[1])) {
		return 1;
	}
	else {
		/* both points are outside but may insersect the rect */
		int tvec1[2];
		int tvec2[2];
		/* diagonal: [/] */
		tvec1[0] = rect->xmin; tvec1[1] = rect->ymin;
		tvec2[0] = rect->xmin; tvec2[1] = rect->ymax;
		if (isect_segments(s1, s2, tvec1, tvec2)) {
			return 1;
		}

		/* diagonal: [\] */
		tvec1[0] = rect->xmin; tvec1[1] = rect->ymax;
		tvec2[0] = rect->xmax; tvec2[1] = rect->ymin;
		if (isect_segments(s1, s2, tvec1, tvec2)) {
			return 1;
		}

		/* no intersection */
		return 0;
	}
}

void BLI_union_rctf(rctf *rct1, rctf *rct2)
{
	if (rct1->xmin > rct2->xmin) rct1->xmin = rct2->xmin;
	if (rct1->xmax < rct2->xmax) rct1->xmax = rct2->xmax;
	if (rct1->ymin > rct2->ymin) rct1->ymin = rct2->ymin;
	if (rct1->ymax < rct2->ymax) rct1->ymax = rct2->ymax;
}

void BLI_union_rcti(rcti *rct1, rcti *rct2)
{
	if (rct1->xmin > rct2->xmin) rct1->xmin = rct2->xmin;
	if (rct1->xmax < rct2->xmax) rct1->xmax = rct2->xmax;
	if (rct1->ymin > rct2->ymin) rct1->ymin = rct2->ymin;
	if (rct1->ymax < rct2->ymax) rct1->ymax = rct2->ymax;
}

void BLI_init_rctf(rctf *rect, float xmin, float xmax, float ymin, float ymax)
{
	if (xmin <= xmax) {
		rect->xmin = xmin;
		rect->xmax = xmax;
	}
	else {
		rect->xmax = xmin;
		rect->xmin = xmax;
	}
	if (ymin <= ymax) {
		rect->ymin = ymin;
		rect->ymax = ymax;
	}
	else {
		rect->ymax = ymin;
		rect->ymin = ymax;
	}
}

void BLI_init_rcti(rcti *rect, int xmin, int xmax, int ymin, int ymax)
{
	if (xmin <= xmax) {
		rect->xmin = xmin;
		rect->xmax = xmax;
	}
	else {
		rect->xmax = xmin;
		rect->xmin = xmax;
	}
	if (ymin <= ymax) {
		rect->ymin = ymin;
		rect->ymax = ymax;
	}
	else {
		rect->ymax = ymin;
		rect->ymin = ymax;
	}
}

void BLI_translate_rcti(rcti *rect, int x, int y)
{
	rect->xmin += x;
	rect->ymin += y;
	rect->xmax += x;
	rect->ymax += y;
}
void BLI_translate_rctf(rctf *rect, float x, float y)
{
	rect->xmin += x;
	rect->ymin += y;
	rect->xmax += x;
	rect->ymax += y;
}

/* change width & height around the central location */
void BLI_resize_rcti(rcti *rect, int x, int y)
{
	rect->xmin = rect->xmax = (rect->xmax + rect->xmin) / 2;
	rect->ymin = rect->ymax = (rect->ymax + rect->ymin) / 2;
	rect->xmin -= x / 2;
	rect->ymin -= y / 2;
	rect->xmax = rect->xmin + x;
	rect->ymax = rect->ymin + y;
}

void BLI_resize_rctf(rctf *rect, float x, float y)
{
	rect->xmin = rect->xmax = (rect->xmax + rect->xmin) * 0.5f;
	rect->ymin = rect->ymax = (rect->ymax + rect->ymin) * 0.5f;
	rect->xmin -= x * 0.5f;
	rect->ymin -= y * 0.5f;
	rect->xmax = rect->xmin + x;
	rect->ymax = rect->ymin + y;
}

int BLI_isect_rctf(rctf *src1, rctf *src2, rctf *dest)
{
	float xmin, xmax;
	float ymin, ymax;

	xmin = (src1->xmin) > (src2->xmin) ? (src1->xmin) : (src2->xmin);
	xmax = (src1->xmax) < (src2->xmax) ? (src1->xmax) : (src2->xmax);
	ymin = (src1->ymin) > (src2->ymin) ? (src1->ymin) : (src2->ymin);
	ymax = (src1->ymax) < (src2->ymax) ? (src1->ymax) : (src2->ymax);

	if (xmax >= xmin && ymax >= ymin) {
		if (dest) {
			dest->xmin = xmin;
			dest->xmax = xmax;
			dest->ymin = ymin;
			dest->ymax = ymax;
		}
		return 1;
	}
	else {
		if (dest) {
			dest->xmin = 0;
			dest->xmax = 0;
			dest->ymin = 0;
			dest->ymax = 0;
		}
		return 0;
	}
}

int BLI_isect_rcti(rcti *src1, rcti *src2, rcti *dest)
{
	int xmin, xmax;
	int ymin, ymax;

	xmin = (src1->xmin) > (src2->xmin) ? (src1->xmin) : (src2->xmin);
	xmax = (src1->xmax) < (src2->xmax) ? (src1->xmax) : (src2->xmax);
	ymin = (src1->ymin) > (src2->ymin) ? (src1->ymin) : (src2->ymin);
	ymax = (src1->ymax) < (src2->ymax) ? (src1->ymax) : (src2->ymax);

	if (xmax >= xmin && ymax >= ymin) {
		if (dest) {
			dest->xmin = xmin;
			dest->xmax = xmax;
			dest->ymin = ymin;
			dest->ymax = ymax;
		}
		return 1;
	}
	else {
		if (dest) {
			dest->xmin = 0;
			dest->xmax = 0;
			dest->ymin = 0;
			dest->ymax = 0;
		}
		return 0;
	}
}

void BLI_copy_rcti_rctf(rcti *tar, const rctf *src)
{
	tar->xmin = floor(src->xmin + 0.5f);
	tar->xmax = floor((src->xmax - src->xmin) + 0.5f);
	tar->ymin = floor(src->ymin + 0.5f);
	tar->ymax = floor((src->ymax - src->ymin) + 0.5f);
}

void print_rctf(const char *str, rctf *rect)
{
	printf("%s: xmin %.3f, xmax %.3f, ymin %.3f, ymax %.3f (%.3fx%.3f)\n", str,
	       rect->xmin, rect->xmax, rect->ymin, rect->ymax, rect->xmax - rect->xmin, rect->ymax - rect->ymin);
}

void print_rcti(const char *str, rcti *rect)
{
	printf("%s: xmin %d, xmax %d, ymin %d, ymax %d (%dx%d)\n", str,
	       rect->xmin, rect->xmax, rect->ymin, rect->ymax, rect->xmax - rect->xmin, rect->ymax - rect->ymin);
}