# HG changeset patch
# User John Tsiombikas <nuclear@member.fsf.org>
# Date 1440458761 -10800
# Node ID bed39534d471b8c1136de51a3d1067aad003f3b3
# Parent  92d662deb66e5ede39e03c9831fc1bff7a31062a
fell back to the equi-radii capsule which works

diff -r 92d662deb66e -r bed39534d471 src/dragon.cc
--- a/src/dragon.cc	Tue Aug 25 00:38:00 2015 +0300
+++ b/src/dragon.cc	Tue Aug 25 02:26:01 2015 +0300
@@ -10,10 +10,11 @@
 #define DYN_FCOUNT		64
 #define DYN_VCOUNT		(DYN_FCOUNT * 3)
 
-#define NUM_NECK_SEG	8
+#define NUM_NECK_SEG	10
 static const float nseg_sizes[NUM_NECK_SEG][2] = {
-	{1.0, 3.0}, {1.0, 1.5}, {1.5, 2.0}, {2.0, 2.5}, {2.5, 3.0}, {3.0, 3.5}
+	{2.0, 2.0}, {1.0, 1.0}, {1.0, 1.0}, {1.25, 1.25}, {1.3, 1.3}, {1.5, 1.5}, {1.6, 1.6}, {1.75, 1.75}, {2.0, 2.0}, {2.1, 2.1}
 };
+#define NSEG_SZ_SCALE	0.5f
 
 static Vector3 bezier(const Vector3 &a, const Vector3 &b, const Vector3 &c, const Vector3 &d, float t);
 static float mseval(struct metasurface *ms, float x, float y, float z);
@@ -36,8 +37,9 @@
 	neck_seg = new Capsule[neck_seg_count];
 
 	for(int i=0; i<neck_seg_count; i++) {
-		neck_seg[i].w[0] = nseg_sizes[i][0];
-		neck_seg[i].w[1] = nseg_sizes[i][1];
+		int idx = neck_seg_count - i - 1;
+		neck_seg[i].w[0] = nseg_sizes[idx][0] * NSEG_SZ_SCALE;
+		neck_seg[i].w[1] = nseg_sizes[idx][1] * NSEG_SZ_SCALE;
 	}
 
 	msurf = msurf_create();
@@ -135,8 +137,8 @@
 
 void Dragon::draw() const
 {
-	static float bmin[] = { head_xlim[0] - VOXEL_PAD * 0.9, head_ylim[0] - VOXEL_PAD, head_pos.z };
-	static float bmax[] = { head_xlim[1] + VOXEL_PAD * 0.9, head_ylim[1] + VOXEL_PAD * 2.1f, pos.z + VOXEL_PAD };
+	static float bmin[] = { head_xlim[0] - VOXEL_PAD * 1.2f, head_ylim[0] - VOXEL_PAD, head_pos.z };
+	static float bmax[] = { head_xlim[1] + VOXEL_PAD * 1.2f, head_ylim[1] + VOXEL_PAD * 2.1f, pos.z + VOXEL_PAD };
 	msurf_set_bounds(msurf, bmin[0], bmin[1], bmin[2], bmax[0], bmax[1], bmax[2]);
 
 
diff -r 92d662deb66e -r bed39534d471 src/geom.cc
--- a/src/geom.cc	Tue Aug 25 00:38:00 2015 +0300
+++ b/src/geom.cc	Tue Aug 25 02:26:01 2015 +0300
@@ -256,6 +256,33 @@
 	return (pt - cent).length() - rad;
 }
 
+// TODO version which takes both radii into account
+float capsule_distance(const Vector3 &a, float ra, const Vector3 &b, float rb, const Vector3 &pt)
+{
+	Vector3 ab_dir = b - a;
+	float ab_len_sq = ab_dir.length_sq();
+
+	if(fabs(ab_len_sq) < 1e-5) {
+		// if a == b, the capsule is a sphere with radius the maximum of the capsule radii
+		return sphere_distance(a, std::max(ra, rb), pt);
+	}
+	float ab_len = sqrt(ab_len_sq);
+
+	Vector3 ap_dir = pt - a;
+
+	float t = dot_product(ap_dir, ab_dir / ab_len) / ab_len;
+	if(t < 0.0) {
+		return sphere_distance(a, ra, pt);
+	}
+	if(t >= 1.0) {
+		return sphere_distance(b, rb, pt);
+	}
+
+	Vector3 pproj = a + ab_dir * t;
+	return (pproj - pt).length() - ra;
+}
+
+#if 0
 float capsule_distance(const Vector3 &a, float ra, const Vector3 &b, float rb, const Vector3 &pt)
 {
 	Vector3 ab_dir = b - a;
@@ -304,3 +331,4 @@
 	}
 	return dist;
 }
+#endif