1 files changed, 89 insertions, 0 deletions
diff --git a/src/m4f-bbx.h b/src/m4f-bbx.h
new file mode 100644
index 0000000..bcae848
--- /dev/null
+++ b/src/m4f-bbx.h
@@ -0,0 +1,89 @@
+/*
+ *  Copyright (C) 2020 - Vito Caputo - <vcaputo@pengaru.com>
+ *
+ *  This program is free software: you can redistribute it and/or modify it
+ *  under the terms of the GNU General Public License version 3 as published
+ *  by the Free Software Foundation.
+ *
+ *  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, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef _M4F_BBX_H
+#define _M4F_BBX_H
+
+#include <float.h>
+
+#include "bb2f.h"
+#include "bb3f.h"
+#include "m4f.h"
+#include "macros.h"
+
+
+/* multiply a matrix and bb3f */
+static bb3f_t * m4f_mult_bb3f(const m4f_t *transform, const bb3f_t *aabb, bb3f_t *res_aabb)
+{
+	v3f_t	box[8] = {
+		{ aabb->min.x, aabb->min.y, aabb->min.z },
+		{ aabb->min.x, aabb->min.y, aabb->max.z },
+		{ aabb->min.x, aabb->max.y, aabb->max.z },
+		{ aabb->min.x, aabb->max.y, aabb->min.z },
+		{ aabb->max.x, aabb->min.y, aabb->min.z },
+		{ aabb->max.x, aabb->min.y, aabb->max.z },
+		{ aabb->max.x, aabb->max.y, aabb->max.z },
+		{ aabb->max.x, aabb->max.y, aabb->min.z },
+	};
+
+	bb3f_t	_aabb = {
+		.min = { FLT_MAX, FLT_MAX, FLT_MAX },
+		.max = { -FLT_MAX, -FLT_MAX, -FLT_MAX},
+	};
+
+	for (int i = 0; i < NELEMS(box); i++) {
+		v3f_t	X = m4f_mult_v3f(transform, &box[i]);
+
+		if (_aabb.min.x > X.x)
+			_aabb.min.x = X.x;
+		if (_aabb.max.x < X.x)
+			_aabb.max.x = X.x;
+
+		if (_aabb.min.y > X.y)
+			_aabb.min.y = X.y;
+		if (_aabb.max.y < X.y)
+			_aabb.max.y = X.y;
+
+		if (_aabb.min.z > X.z)
+			_aabb.min.z = X.z;
+		if (_aabb.max.z < X.z)
+			_aabb.max.z = X.z;
+	}
+
+	*res_aabb = _aabb;
+
+	return res_aabb;
+}
+
+
+/* multiply a matrix and a bb3f but return only the x,y components in a bb2f */
+/* Caller must supply the storage in res_aabb, for convenience this is also returned. */
+static bb2f_t * m4f_mult_bb3f_bb2f(const m4f_t *transform, const bb3f_t *aabb, bb2f_t *res_aabb)
+{
+	bb3f_t	_aabb;
+
+	m4f_mult_bb3f(transform, aabb, &_aabb);
+
+	res_aabb->min.x = _aabb.min.x;
+	res_aabb->min.y = _aabb.min.y;
+	res_aabb->max.x = _aabb.max.x;
+	res_aabb->max.y = _aabb.max.y;
+
+	return res_aabb;
+}
+
+
+#endif