From: havoc <havoc@d7cf8633-e32d-0410-b094-e92efae38249>
Date: Mon, 11 Aug 2008 01:54:26 +0000 (+0000)
Subject: ported some features over from darkwar matrixlib.[ch]
X-Git-Tag: xonotic-v0.1.0preview~2139
X-Git-Url: http://de.git.xonotic.org/?a=commitdiff_plain;h=49527da111ad96c720d540effb651e9c32a4899b;p=xonotic%2Fdarkplaces.git

ported some features over from darkwar matrixlib.[ch]


git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@8442 d7cf8633-e32d-0410-b094-e92efae38249
---

diff --git a/matrixlib.c b/matrixlib.c
index a0499861..7b7bfad6 100644
--- a/matrixlib.c
+++ b/matrixlib.c
@@ -362,6 +362,30 @@ void Matrix4x4_Invert_Simple (matrix4x4_t *out, const matrix4x4_t *in1)
 #endif
 }
 
+void Matrix4x4_Interpolate (matrix4x4_t *out, matrix4x4_t *in1, matrix4x4_t *in2, double frac)
+{
+	int i, j;
+	for (i = 0;i < 4;i++)
+		for (j = 0;j < 4;j++)
+			out->m[i][j] = in1->m[i][j] + frac * (in2->m[i][j] - in1->m[i][j]);
+}
+
+void Matrix4x4_Clear (matrix4x4_t *out)
+{
+	int i, j;
+	for (i = 0;i < 4;i++)
+		for (j = 0;j < 4;j++)
+			out->m[i][j] = 0;
+}
+
+void Matrix4x4_Accumulate (matrix4x4_t *out, matrix4x4_t *in, double weight)
+{
+	int i, j;
+	for (i = 0;i < 4;i++)
+		for (j = 0;j < 4;j++)
+			out->m[i][j] += in->m[i][j] * weight;
+}
+
 void Matrix4x4_Normalize (matrix4x4_t *out, matrix4x4_t *in1)
 {
 	// scale rotation matrix vectors to a length of 1
@@ -371,6 +395,33 @@ void Matrix4x4_Normalize (matrix4x4_t *out, matrix4x4_t *in1)
 	Matrix4x4_Scale(out, scale, 1);
 }
 
+void Matrix4x4_Normalize3 (matrix4x4_t *out, matrix4x4_t *in1)
+{
+	int i;
+	double scale;
+	// scale each rotation matrix vector to a length of 1
+	// intended for use after Matrix4x4_Interpolate or Matrix4x4_Accumulate
+	*out = *in1;
+	for (i = 0;i < 3;i++)
+	{
+#ifdef MATRIX4x4_OPENGLORIENTATION
+		scale = sqrt(in1->m[i][0] * in1->m[i][0] + in1->m[i][1] * in1->m[i][1] + in1->m[i][2] * in1->m[i][2]);
+		if (scale)
+			scale = 1.0 / scale;
+		out->m[i][0] *= scale;
+		out->m[i][1] *= scale;
+		out->m[i][2] *= scale;
+#else
+		scale = sqrt(in1->m[0][i] * in1->m[0][i] + in1->m[1][i] * in1->m[1][i] + in1->m[2][i] * in1->m[2][i]);
+		if (scale)
+			scale = 1.0 / scale;
+		out->m[0][i] *= scale;
+		out->m[1][i] *= scale;
+		out->m[2][i] *= scale;
+#endif
+	}
+}
+
 void Matrix4x4_Reflect (matrix4x4_t *out, double normalx, double normaly, double normalz, double dist, double axisscale)
 {
 	int i;
diff --git a/matrixlib.h b/matrixlib.h
index 480dec15..8e1e6537 100644
--- a/matrixlib.h
+++ b/matrixlib.h
@@ -39,9 +39,23 @@ int Matrix4x4_Invert_Full (matrix4x4_t *out, const matrix4x4_t *in1);
 // creates a matrix that does the opposite of the matrix provided
 // only supports translate, rotate, scale (not scale3) matrices
 void Matrix4x4_Invert_Simple (matrix4x4_t *out, const matrix4x4_t *in1);
+// blends between two matrices, used primarily for animation interpolation
+// (note: it is recommended to follow this with Matrix4x4_Normalize, a method
+//  known as nlerp rotation, often better for animation purposes than slerp)
+void Matrix4x4_Interpolate (matrix4x4_t *out, matrix4x4_t *in1, matrix4x4_t *in2, double frac);
+// zeros all matrix components, used with Matrix4x4_Accumulate
+void Matrix4x4_Clear (matrix4x4_t *out);
+// adds a weighted contribution from the supplied matrix, used to blend 3 or
+// more matrices with weighting, it is recommended that Matrix4x4_Normalize be
+// called afterward (a method known as nlerp rotation, often better for
+// animation purposes than slerp)
+void Matrix4x4_Accumulate (matrix4x4_t *out, matrix4x4_t *in, double weight);
 // creates a matrix that does the same rotation and translation as the matrix
 // provided, but no uniform scaling, does not support scale3 matrices
 void Matrix4x4_Normalize (matrix4x4_t *out, matrix4x4_t *in1);
+// creates a matrix with vectors normalized individually (use after
+// Matrix4x4_Accumulate)
+void Matrix4x4_Normalize3 (matrix4x4_t *out, matrix4x4_t *in1);
 // modifies a matrix to have all vectors and origin reflected across the plane
 // to the opposite side (at least if axisscale is -2)
 void Matrix4x4_Reflect (matrix4x4_t *out, double normalx, double normaly, double normalz, double dist, double axisscale);