/// <summary>
/// Update the parameters if anything changes
/// </summary>
void Update()
{
// early out if no updating is requested
if (!AutoUpdate)
{
return;
}
// create a new mesh if the divisions have changed
if (m_PreviousDivisions != Divisions)
{
CreateMeshRibbon();
}
// recompute vertex positions if helix has changed
if (!Helix.AreEquivalent(m_PreviousHelix, Helix))
{
RecalculateVertexPositions();
}
// compute uvs if the scale has changed
if (!AutoVScale && (m_PreviousVScale != VScale))
{
RecalculateUVCoordinates();
}
// store old values
m_PreviousHelix = new Helix(m_PreviousHelix);
m_PreviousDivisions = Divisions;
m_PreviousVScale = VScale;
}
/// <summary>
/// Display a wire ribbon handle.
/// </summary>
/// <returns>A new helix with any modifications applied.</returns>
/// <param name="baseId">Base identifier. Each handle has its own unique hash based off this value.</param>
/// <param name="helix">Helix.</param>
/// <param name="origin">Origin.</param>
/// <param name="orientation">Orientation.</param>
/// <param name="scale">Scale.</param>
/// <param name="color">Color.</param>
public static Helix WireRibbon(
int baseId, Helix helix, Vector3 origin, Quaternion orientation, Vector3 scale, Color color
)
{
return(DoHelixHandle(
baseId, helix, origin, orientation, scale, color, s_SmoothDivisionCount, FillMode.Wire, ShapeMode.Ribbon
));
}
/// <summary>
/// Display a solid helix handle.
/// </summary>
/// <returns>A new helix with any modifications applied.</returns>
/// <param name="baseId">Base identifier. Each handle has its own unique hash based off this value.</param>
/// <param name="helix">Helix.</param>
/// <param name="origin">Origin.</param>
/// <param name="orientation">Orientation.</param>
/// <param name="scale">Scale.</param>
/// <param name="color">Color.</param>
public static Helix SolidHelix(
int baseId, Helix helix, Vector3 origin, Quaternion orientation, Vector3 scale, Color color
)
{
return(DoHelixHandle(
baseId, helix, origin, orientation, scale, color, s_SmoothDivisionCount, FillMode.Solid, ShapeMode.Helix
));
}
/// <summary>
/// Creates the mesh ribbon.
/// </summary>
private void CreateMeshRibbon()
{
// validate data
Divisions = Mathf.Max(Divisions, 1);
// compute vertex positions, normals, and uv coordinates
Vector3[] vertices = new Vector3[2 * (Divisions + 1)];
Vector3[] normals = new Vector3[vertices.Length];
Vector2[] uv = new Vector2[vertices.Length];
// cache divisions
float oneHalfLengthOverDivisions = 0.5f * Helix.Length / Divisions;
float oneHalfActualUVScale = 0.5f / VScale / Divisions;
for (int i = 0; i < vertices.Length; i += 2)
{
// compute vertex positions
float parameter = (float)(i) * oneHalfLengthOverDivisions;
vertices[i] = Helix.Evaluate(parameter);
vertices[i + 1] = Helix.EvaluateOpposite(parameter);
// compute uvs
uv[i] = new Vector2(1f, (float)(i) * oneHalfActualUVScale);
uv[i + 1] = new Vector2(0f, uv[i].y);
}
// compute triangles
int[] triangles = new int[Divisions * 6];
bool isEvenTriangle = true;
int stepCount = 3;
for (int i = 0; i < triangles.Length; i += stepCount)
{
int start = i / stepCount;
if (isEvenTriangle)
{
triangles[i] = start;
triangles[i + 1] = start + 1;
triangles[i + 2] = start + 2;
}
else
{
triangles[i] = start + 2;
triangles[i + 1] = start + 1;
triangles[i + 2] = start;
}
isEvenTriangle = !isEvenTriangle;
}
// create the mesh
MeshFilter.mesh.Clear();
MeshFilter.mesh.vertices = vertices;
MeshFilter.mesh.normals = normals;
MeshFilter.mesh.triangles = triangles;
MeshFilter.mesh.uv = uv;
MeshFilter.mesh.RecalculateNormals();
MeshFilter.mesh.RecalculateBounds();
// scale uvs if required
if (AutoVScale)
{
RecalculateUVCoordinates();
}
}
/// <summary>
/// Initializes a new instance of the <see cref="Helix"/> class.
/// </summary>
/// <param name="helix">Helix.</param>
/// <exception cref='System.ArgumentNullException'>
/// Is thrown when a <see langword="null" /> Helix is passed.
/// </exception>
public Helix(Helix helix)
{
if (helix == null)
{
throw new System.ArgumentNullException("helix");
}
else
{
this.Length = helix.Length;
this.AutoSmoothCurveTangents = helix.AutoSmoothCurveTangents;
Twist = helix.Twist;
Width = helix.Width;
}
}
/// <summary>
/// Recompute vertex positions, as when the helix changes.
/// </summary>
private void RecalculateVertexPositions()
{
Vector3[] vertices = MeshFilter.mesh.vertices;
float oneHalfLengthOverDivisions = 0.5f * Helix.Length / Divisions;
for (int i = 0; i < vertices.Length; i += 2)
{
float parameter = (float)(i) * oneHalfLengthOverDivisions;
vertices[i] = Helix.Evaluate(parameter);
vertices[i + 1] = Helix.EvaluateOpposite(parameter);
}
MeshFilter.mesh.vertices = vertices;
if (AutoVScale)
{
RecalculateUVCoordinates();
}
}
/// <summary>
/// Display a helix handle.
/// </summary>
/// <returns>A new helix with any modifications applied.</returns>
/// <param name="baseId">Base identifier. Each handle has its own unique hash based off this value.</param>
/// <param name="helix">Helix.</param>
/// <param name="origin">Origin.</param>
/// <param name="orientation">Orientation.</param>
/// <param name="scale">Scale.</param>
/// <param name="color">Color.</param>
/// <param name="divisions">Divisions.</param>
/// <param name="fillMode">Fill mode.</param>
/// <param name="shapeMode">Shape mode.</param>
private static Helix DoHelixHandle(
int baseId,
Helix helix,
Vector3 origin,
Quaternion orientation,
Vector3 scale,
Color color,
int divisions,
FillMode fillMode,
ShapeMode shapeMode
)
{
// early out if the scale is too small
if (scale.sqrMagnitude < s_RequiredMinHandleChange)
{
Debug.LogWarning("Scale vector for helix handle is too close to 0. Handle is disabled");
return(null);
}
// create copy of helix
helix = new Helix(helix);
// store the handle matrix
Matrix4x4 oldMatrix = Handles.matrix;
Handles.matrix *= Matrix4x4.TRS(origin, orientation, scale);
// set the helix handle's color
Color oldColor = Handles.color;
Handles.color = color;
// validate the number of divisions
divisions = Mathf.Max(1, divisions);
// create a handle to adjust length
DoHelixLengthHandle(baseId, helix);
// next, create handles for the twist curve
DoHelixTwistHandles(baseId, helix);
// next, create handles for the width curve
DoHelixWidthHandles(baseId, helix);
// draw lines to visualize the helix
DrawHelix(helix, divisions, fillMode, shapeMode);
// reset handle color
Handles.color = oldColor;
// reset handle matrix
Handles.matrix = oldMatrix;
// return result
return(helix);
}
/// <summary>
/// Displays the helix twist curve handles.
/// </summary>
/// <param name="baseId">Base identifier.</param>
/// <param name="helix">Helix.</param>
private static void DoHelixTwistHandles(int baseId, Helix helix)
{
float v;
AnimationCurve width = helix.Width;
AnimationCurve newTwist = new AnimationCurve(helix.Twist.keys);
Keyframe[] newKeys = newTwist.keys;
for (int i = 0; i < newKeys.Length; ++i)
{
// compute the disc center
Vector3 discCenter = Vector3.forward * newKeys[i].time * helix.Length;
v = newKeys[i].value;
// create an arc handle
float helixWidth = width.Evaluate(newKeys[i].time);
v = ArcHandles.SolidAngle(
ObjectX.GenerateHashCode(baseId, s_TwistHandleHash, i, 1),
v, discCenter,
Quaternion.LookRotation(Vector3.right, Vector3.forward),
helixWidth,
string.Format("{0:0} Degrees", v)
);
Handles.DrawWireDisc(discCenter, Vector3.forward, helixWidth);
newKeys[i].value = v;
// create time adjustment handles for intermediary keys
if (i == 0 || i == newKeys.Length - 1)
{
continue;
}
v = newKeys[i].time * helix.Length;
int id = ObjectX.GenerateHashCode(baseId, s_TwistHandleHash, i, 2);
v = LinearHandles.Cone(id, v, Vector3.zero, Vector3.forward, capScale: s_TimeAdjustHandleSize);
v = Mathf.Clamp(
v / helix.Length,
Mathf.Epsilon * 2f,
1f - Mathf.Epsilon * 2f
);
if (Mathf.Abs(v - newKeys[i].time) > s_RequiredMinHandleChange)
{
newKeys[i].time = v;
}
// TODO: Fix problems with keys moving over each other
}
newTwist.keys = newKeys;
helix.Twist = newTwist;
}
/// <summary>
/// Display a helix length handle.
/// </summary>
/// <param name="baseId">Base identifier.</param>
/// <param name="helix">Helix.</param>
private static void DoHelixLengthHandle(int baseId, Helix helix)
{
float length = helix.Length;
int id = ObjectX.GenerateHashCode(baseId, s_LengthHandleHash);
length = LinearHandles.Arrow(
id,
length,
Vector3.zero,
Vector3.forward,
string.Format("Length: {0:0.###}", length),
s_LengthHandleSize
);
if (Mathf.Abs(length - helix.Length) < s_RequiredMinHandleChange)
{
length = helix.Length;
}
helix.Length = length;
}
/// <summary>
/// Displays helix width handles.
/// </summary>
/// <param name="baseId">Base identifier.</param>
/// <param name="helix">Helix.</param>
private static void DoHelixWidthHandles(int baseId, Helix helix)
{
float v;
AnimationCurve twist = helix.Twist;
AnimationCurve newWidth = helix.Width;
Keyframe[] newKeys = newWidth.keys;
for (int i = 0; i < newKeys.Length; ++i)
{
// compute the disc center
Vector3 discCenter = Vector3.forward * newKeys[i].time * helix.Length;
// compute the angle of the handle around the length
Quaternion angle = Quaternion.AngleAxis(twist.Evaluate(newKeys[i].time), Vector3.forward);
// create a cone handle with a slight offset to not overlap the arc handle
v = newKeys[i].value + s_WidthHandleOffset;
int id = ObjectX.GenerateHashCode(baseId, s_WidthHandleHash, i, 1);
v = LinearHandles.Cone(id, v, discCenter, angle * Vector3.right, capScale: s_WidthHandleSize);
newKeys[i].value = v - s_WidthHandleOffset;
// create time adjustment handles for intermediary keys
if (i == 0 || i == newKeys.Length - 1)
{
continue;
}
v = newKeys[i].time * helix.Length;
id = ObjectX.GenerateHashCode(baseId, s_WidthHandleHash, i, 2);
v = LinearHandles.Cone(id, v, Vector3.zero, Vector3.forward, capScale: s_TimeAdjustHandleSize);
v = Mathf.Clamp(
v / helix.Length,
Mathf.Epsilon * 2f,
1f - Mathf.Epsilon * 2f
);
if (Mathf.Abs(v - newKeys[i].time) > s_RequiredMinHandleChange)
{
newKeys[i].time = v;
}
// TODO: Fix problems with keys moving over each other
}
newWidth.keys = newKeys;
helix.Width = newWidth;
}
/// <summary>
/// Initialize
/// </summary>
void Start()
{
// create the mesh
if (MeshFilter == null)
{
MeshFilter = gameObject.AddComponent <MeshFilter>();
}
if (MeshFilter.mesh == null)
{
MeshFilter.mesh = new Mesh();
MeshFilter.mesh.name = name + " Helix Mesh Ribbon";
}
CreateMeshRibbon();
if (AutoVScale)
{
AutoComputeVScale();
}
// store the old values
m_PreviousHelix = Helix;
m_PreviousDivisions = Divisions;
m_PreviousVScale = VScale;
}
/// <summary>
/// Tests if two helices are equivalent.
/// </summary>
/// <returns>
/// <see langword="true"/> if all field values are equivalent; otherwise, <see langword="false"/>.
/// </returns>
/// <param name="h1">Helix 1.</param>
/// <param name="h2">Helix 2.</param>
public static bool AreEquivalent(Helix h1, Helix h2)
{
if (h1 == null)
{
return(h2 == null);
}
else if (h2 == null)
{
return(false);
}
else if (
h1.AutoSmoothCurveTangents == h2.AutoSmoothCurveTangents &&
h1.Length == h2.Length &&
h1.Twist.IsValueEqualTo(h2.Twist) &&
h1.Width.IsValueEqualTo(h2.Width)
)
{
return(true);
}
else
{
return(false);
}
}
public static Helix WireRibbon(Helix helix, Vector3 origin, Quaternion orientation, Vector3 scale, Color color)
{
return(WireRibbon(0, helix, origin, orientation, scale, color));
}
public static void SolidHelix(Helix helix, Vector3 origin, Quaternion orientation, Vector3 scale, Color color)
{
SolidHelix(0, helix, origin, orientation, scale, color);
}
/// <summary>
/// Draws the helix.
/// </summary>
/// <param name="helix">Helix.</param>
/// <param name="divisions">Divisions.</param>
/// <param name="fillMode">Fill mode.</param>
/// <param name="shapeMode">Shape mode.</param>
private static void DrawHelix(Helix helix, int divisions, FillMode fillMode, ShapeMode shapeMode)
{
// early out if not repaint phase
if (Event.current.type != EventType.Repaint)
{
return;
}
// initialize mesh properties
Vector3[] vertices = new Vector3[divisions * 2 + 2];
Vector2[] uv = new Vector2[vertices.Length];
Color[] colors = new Color[vertices.Length];
int[] triangles = new int[divisions * 12];
// compute mesh data
bool isRibbon = shapeMode == ShapeMode.Ribbon;
bool isSolid = fillMode != FillMode.Wire;
bool isMesh = fillMode == FillMode.Mesh;
float oneHalfLengthOverDivisions = 0.5f * helix.Length / divisions;
for (int i = 0; i < vertices.Length; i += 2)
{
// current parameter value
float parameter = (float)(i) * oneHalfLengthOverDivisions;
// compute vertex
vertices[i] = helix.Evaluate(parameter);
// draw line
if (i > 0)
{
Handles.DrawLine(vertices[i - 2], vertices[i]);
}
// compute corresponding vertex
if (isRibbon)
{
vertices[i + 1] = helix.EvaluateOpposite(parameter);
// draw opposite line
if (i > 0)
{
Handles.DrawLine(vertices[i - 1], vertices[i + 1]);
}
}
else
{
vertices[i + 1].z = vertices[i].z;
}
// draw connecting lines if requested
if (isMesh)
{
Handles.DrawLine(vertices[i], vertices[i + 1]);
}
// populate colors
colors[i] = Handles.color;
colors[i].a *= SceneGUI.FillAlphaScalar;
colors[i + 1] = colors[i];
}
// compute triangles
int stepCount = 6;
for (int i = 0; i < triangles.Length; i += stepCount)
{
int start = i / stepCount;
triangles[i] = start;
triangles[i + 1] = start + 1;
triangles[i + 2] = start + 2;
triangles[i + 3] = start + 2;
triangles[i + 4] = start + 1;
triangles[i + 5] = start;
}
// update mesh
if (s_FillMesh == null)
{
s_FillMesh = new Mesh();
s_FillMesh.hideFlags = HideFlags.DontSave;
}
s_FillMesh.Clear();
s_FillMesh.vertices = vertices;
s_FillMesh.colors = colors;
s_FillMesh.triangles = triangles;
s_FillMesh.uv = uv;
s_FillMesh.RecalculateNormals();
// draw the mesh
if (isSolid)
{
Graphics.DrawMeshNow(s_FillMesh, Handles.matrix);
}
}
